Acquired immunodeficiency syndrome (AIDS) Classification and external resources
The Red ribbon is a symbol for solidarity with HIV-positive people and those living with AIDS. The red ribbon, a Ribbon colored Red, has several different meanings in different contexts
ICD-10	B24.
ICD-9	042
DiseasesDB	5938
MedlinePlus	000594
eMedicine	emerg/253
MeSH	D000163

Acquired immune deficiency syndrome or acquired immunodeficiency syndrome (AIDS or Aids) is a set of symptoms and infections resulting from the damage to the human immune system caused by the human immunodeficiency virus (HIV). The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The International Statistical Classification of Diseases and Related Health Problems 10th Revision ( ICD -10) is a coding of diseases and signs symptoms abnormal findings A00-A79 - Bacterial infections and other intestinal infectious diseases and STDs (A00-A09 Intestinal Infectious diseases ( The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. The Diseases Database is a free Website that provides information about the relationships between medical conditions Symptoms, and Medications. MedlinePlus, with the MedlinePlus Medical Encyclopedia, is a website network containing Health information from the world's largest medical Library eMedicine is an online clinical medical knowledge base that was founded in 1996 by Scott Plantz and Richard Lavely two medical doctors Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome T helper cells (also known as effector T cells or Th cells) are a sub-group of Lymphocytes (a type of White blood cell or CCR5, short for chemokine (C-C motif receptor 5, is a Chemokine receptor. The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common A sexually transmitted disease ( STD) or venereal disease ( VD) is an illness that has a significant probability of transmission between Humans In Medicine and Psychology, the term syndrome refers to the association of several clinically recognizable features signs (observed by a physician An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome ^[1] This condition progressively reduces the effectiveness of the immune system and leaves individuals susceptible to opportunistic infections and tumors. An opportunistic infection is an infection caused by Pathogens that usually do not cause disease in a healthy Immune system. See also Cancer A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic HIV is transmitted through direct contact of a mucous membrane or the bloodstream with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid, and breast milk. In Medicine, transmission is the passing of a Disease from an infected individual or group to a previously uninfected individual or group The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin covered in Epithelium, which are involved in Bodily fluids listed below are found in the bodies of men and/or women Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products Physiological aspects Internal and external fertilization Depending on the Species, spermatozoa can fertilize Vaginal lubrication is the naturally produced lubricating fluid that reduces friction during Sexual intercourse. Pre-ejaculate (also known as pre-ejaculatory fluid or Cowper's fluid, and colloquially as pre-cum) is the clear colorless viscous fluid that Breast milk refers to the Milk produced by a mother to feed her baby ^[2][3] This transmission can involve anal, vaginal or oral sex, blood transfusion, contaminated hypodermic needles, exchange between mother and baby during pregnancy, childbirth, or breastfeeding, or other exposure to one of the above bodily fluids. Anal sex most often refers to the sex act involving insertion of the Penis into the Rectum. Sexual intercourse, in its biological sense is the act in which the male reproductive organ (in humans and other higher animals enters the female reproductive tract Oral sex refers to sexual activities involving the use of the Mouth, and may include use of the Tongue, Teeth, and Throat, in order Sexual intercourse, in its biological sense is the act in which the male reproductive organ (in humans and other higher animals enters the female reproductive tract Blood transfusion is the process of transferring Blood or blood-based products from one person into the Circulatory system of another A hypodermic needle is a hollow needle commonly used with a Syringe to inject substances into the body Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female Childbirth (also called labour, birth, partus or parturition) is the culmination of a Human Pregnancy or Breastfeeding is the feeding of an Infant or young Child with Breast milk directly from human Breasts, not from a Baby bottle or other

AIDS is now a pandemic. A pandemic (from Greek παν pan all + δήμος demos people is an Epidemic of Infectious disease that spreads through ^[4] In 2007, an estimated 33. 2 million people lived with the disease worldwide, and it killed an estimated 2. 1 million people, including 330,000 children. ^[5] Over three-quarters of these deaths occurred in sub-Saharan Africa,^[5] retarding economic growth and destroying human capital. Economic growth is the increase in the amount of the goods and services produced by an economy over time Human capital refers to the stock of skills and knowledge embodied in the ability to perform labor so as to produce Economic value. ^[6] Most researchers believe that HIV originated in sub-Saharan Africa during the twentieth century. Sub-Saharan Africa is a geographical term used to describe the area of the African continent which lies south of the Sahara, or those African countries ^[7] The disease was first identified by the U. S. Centers for Disease Control and Prevention in 1981 and its cause identified by American and French scientists in the late 1980s. The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated ^[8]

Although treatments for AIDS and HIV can slow the course of the disease, there is currently no vaccine or cure. Antiretroviral treatment reduces both the mortality and the morbidity of HIV infection, but these drugs are expensive and routine access to antiretroviral medication is not available in all countries. Mortality rate is a measure of the number of Deaths (in general or due to a specific cause in some population scaled to the size of that population per unit time Medication, also referred to as medicine, can be loosely defined as any substance intended for use in the diagnosis cure mitigation treatment or prevention of disease ^[9] Due to the difficulty in treating HIV infection, preventing infection is a key aim in controlling the AIDS epidemic, with health organizations promoting safe sex and needle-exchange programmes in attempts to slow the spread of the virus. Safe sex (also called safer sex or protected sex) is the practice of Sexual activity in a manner that reduces the risk of Infection with A hypodermic needle-exchange program is a sometimes controversial Social policy, based on the philosophy of Harm reduction where injection

Symptoms

A generalized graph of the relationship between HIV copies (viral load) and CD4 counts over the average course of untreated HIV infection; any particular individual's disease course may vary considerably.                      CD4⁺ T Lymphocyte count (cells/mm³)                      HIV RNA copies per mL of plasma

The symptoms of AIDS are primarily the result of conditions that do not normally develop in individuals with healthy immune systems. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor Most of these conditions are infections caused by bacteria, viruses, fungi and parasites that are normally controlled by the elements of the immune system that HIV damages. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Parasitism is a type of symbiotic relationship between Organisms of different Species. Opportunistic infections are common in people with AIDS. An opportunistic infection is an infection caused by Pathogens that usually do not cause disease in a healthy Immune system. ^[10] HIV affects nearly every organ system. In Biology, a system is a group of organs that work together to perform a certain task People with AIDS also have an increased risk of developing various cancers such as Kaposi's sarcoma, cervical cancer and cancers of the immune system known as lymphomas. Kaposi's sarcoma (KS is a tumor caused by Human herpesvirus 8 ( HHV8) also known as Kaposi's sarcoma-associated herpesvirus (KSHV Cervical cancer is Malignant Cancer of the Cervix uteri or cervical area Lymphoma a type of Neoplasm that originates in Lymphocytes (a type of White blood cell in the vertebrate Immune system) Additionally, people with AIDS often have systemic symptoms of infection like fevers, sweats (particularly at night), swollen glands, chills, weakness, and weight loss. Fever (also known as pyrexia, from the Greek pyretos meaning fire or a febrile response, from the Latin word Febris Weight loss, in the context of Medicine or Health or Physical fitness, is a reduction of the total Body weight, due to a mean loss of fluid ^[11][12] The specific opportunistic infections that AIDS patients develop depend in part on the prevalence of these infections in the geographic area in which the patient lives.

Pulmonary infections

X-ray of Pneumocystis jirovecii caused pneumonia. Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced There is increased white (opacity) in the lower lungs on both sides, characteristic of Pneumocystis pneumonia

Pneumocystis pneumonia (originally known as Pneumocystis carinii pneumonia, and still abbreviated as PCP, which now stands for Pneumocystis pneumonia) is relatively rare in healthy, immunocompetent people, but common among HIV-infected individuals. Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Immunocompetence is the ability of the body to produce a normal Immune response (i It is caused by Pneumocystis jirovecii. Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Before the advent of effective diagnosis, treatment and routine prophylaxis in Western countries, it was a common immediate cause of death. Prophylaxis ( Greek "προφυλάσσω" to guard or prevent beforehand) is any medical or Public health procedure whose purpose In developing countries, it is still one of the first indications of AIDS in untested individuals, although it does not generally occur unless the CD4 count is less than 200 cells per µL of blood. ^[13]

Tuberculosis (TB) is unique among infections associated with HIV because it is transmissible to immunocompetent people via the respiratory route, is easily treatable once identified, may occur in early-stage HIV disease, and is preventable with drug therapy. Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common However, multidrug resistance is a potentially serious problem. Multidrug resistance is a condition enabling a disease-causing organism to resist distinct Drugs or chemicals of a wide variety of structure and function targeted at eradicating Even though its incidence has declined because of the use of directly observed therapy and other improved practices in Western countries, this is not the case in developing countries where HIV is most prevalent. In early-stage HIV infection (CD4 count >300 cells per µL), TB typically presents as a pulmonary disease. In advanced HIV infection, TB often presents atypically with extrapulmonary (systemic) disease a common feature. Symptoms are usually constitutional and are not localized to one particular site, often affecting bone marrow, bone, urinary and gastrointestinal tracts, liver, regional lymph nodes, and the central nervous system. Bone marrow is the flexible tissue found in the hollow interior of Bones In adults marrow in large bones produces new Blood cells It constitutes 4% of Bones are rigid organs that form part of the Endoskeleton of Vertebrates They function to move support and protect the various organs of the body produce The liver is a vital organ in the human body and is present in Vertebrates and some other animals A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. In Vertebrates the central nervous system ( CNS) is the part of the Nervous system which is enclosed in the Meninges. ^[14]

Gastrointestinal infections

Esophagitis is an inflammation of the lining of the lower end of the esophagus (gullet or swallowing tube leading to the stomach). Esophagitis (or Oesophagitis) is Inflammation of the Esophagus. The esophagus or oesophagus (see American and British English spelling differences) sometimes known as the gullet, is an organ in In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following In HIV infected individuals, this is normally due to fungal (candidiasis) or viral (herpes simplex-1 or cytomegalovirus) infections. Candidiasis, commonly called yeast infection or thrush, is a Fungal infection (mycosis of any of the Candida species of which Herpes simplex virus 1 and 2 ( HSV-1 and HSV-2) are two species of the herpes virus family Herpesviridae, which cause infections Cytomegalovirus (CMV (from the Greek cyto-, "cell" and -megalo-, "large" is a viral In rare cases, it could be due to mycobacteria. Mycobacterium is a Genus of Actinobacteria, given its own family the Mycobacteriaceae ^[15]

Unexplained chronic diarrhea in HIV infection is due to many possible causes, including common bacterial (Salmonella, Shigella, Listeria or Campylobacter) and parasitic infections; and uncommon opportunistic infections such as cryptosporidiosis, microsporidiosis, Mycobacterium avium complex (MAC) and viruses,^[16] astrovirus, adenovirus, rotavirus and cytomegalovirus, (the latter as a course of colitis). In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea Salmonella is a Genus of rod-shaped Gram-negative enterobacteria that causes Typhoid fever, Paratyphoid fever This article is about the bacteria For the disease see Shigellosis Shigella is a Genus of Gram-negative Listeria is a Bacterial Genus containing six species Named in honour of Joseph Lister, Listeria species are Gram-positive The Genus Campylobacter, (meaning 'twisted bacteria' first discovered in 1963 describes Gram-negative, spiral Microaerophilic bacteria Cryptosporidiosis is a Parasitic disease caused by Cryptosporidium, a Protozoan Parasite in the phylum Apicomplexa. Microspridiosis is an opportunistic intestinal infection that causes Diarrhea and wasting in Immunocompromised individuals ( HIV, for example Mycobacterium avium complex (MAC is a group of Genetically -related Bacteria belonging to the genus Mycobacterium. Astrovirus is a type of Virus that infects Mammals and Birds. Adenoviruses are medium-sized (90–100 nm) Nonenveloped (naked Icosahedral viruses composed of a nucleocapsid and a double-stranded linear DNA Rotavirus is a Genus of Double-stranded RNA virus in the family Reoviridae. Cytomegalovirus (CMV (from the Greek cyto-, "cell" and -megalo-, "large" is a viral Colitis is a chronic digestive disease characterized by Inflammation of the colon. In some cases, diarrhea may be a side effect of several drugs used to treat HIV, or it may simply accompany HIV infection, particularly during primary HIV infection. It may also be a side effect of antibiotics used to treat bacterial causes of diarrhea (common for Clostridium difficile). In modern usage an antibiotic is a Chemotherapeutic agent with activity against Microorganisms such as Bacteria, fungi or Protozoa Clostridium difficile (pronounced /klɒsˈtrɪdiəm dɪˈfɪsɪli/ also known as CDF/cdf' or 'C In the later stages of HIV infection, diarrhea is thought to be a reflection of changes in the way the intestinal tract absorbs nutrients, and may be an important component of HIV-related wasting. Wasting could also mean unefficient and/or uneffective consumption. ^[17]

Neurological diseases

Toxoplasmosis is a disease caused by the single-celled parasite called Toxoplasma gondii; it usually infects the brain causing toxoplasma encephalitis but it can infect and cause disease in the eyes and lungs. Toxoplasmosis is a Parasitic disease caused by the Protozoan Toxoplasma gondii. Parasitism is a type of symbiotic relationship between Organisms of different Species. Encephalitis is an acute Inflammation of the Brain, commonly caused by a viral Infection. Eyes are organs that detect Light, and send signals along the Optic nerve to the visual areas of the brain ^[18]

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease, in which the gradual destruction of the myelin sheath covering the axons of nerve cells impairs the transmission of nerve impulses. Progressive multifocal leukoencephalopathy (PML also known as progressive multifocal leukoencephalitis is a rare and usually fatal viral disease that is characterized by progressive A demyelinating disease is any Disease of the Nervous system in which the Myelin sheath of Neurons is damaged Myelin is an electrically-insulating Dielectric Phospholipid layer that surrounds only the Axons of many Neurons It is an outgrowth An axon or nerve fiber is a long slender projectionof a nerve cell or Neuron, that conducts electrical impulses away from the neuron's Cell It is caused by a virus called JC virus which occurs in 70% of the population in latent form, causing disease only when the immune system has been severely weakened, as is the case for AIDS patients. The JC virus or John Cunningham virus (JCV is a type of human Polyomavirus (formerly known as papovavirus and is genetically similar to BK virus and SV40 Chronic since 1992 ( talk) 2200 12 December 2007 (UTC --> Virus latency It progresses rapidly, usually causing death within months of diagnosis. ^[19] AIDS dementia complex (ADC) is a metabolic encephalopathy induced by HIV infection and fueled by immune activation of HIV infected brain macrophages and microglia which secrete neurotoxins of both host and viral origin. AIDS dementia complex ( ADC; also known as HIV dementia, HIV encephalopathy and HIV-associated dementia) is a common neurological disorder Encephalopathy /ɛnˌsɛfəˈlɒpəθi/ literally means Disease of the Brain. Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that Microglia are a type of Glial cell that acts as the first and main form of active immune defense in the Central nervous system (CNS A neurotoxin is a Toxin that acts specifically on nerve cells ( Neurons, usually by interacting with Membrane proteins such as Ion channels ^[20] Specific neurological impairments are manifested by cognitive, behavioral, and motor abnormalities that occur after years of HIV infection and is associated with low CD4⁺ T cell levels and high plasma viral loads. Prevalence is 10–20% in Western countries^[21] but only 1–2% of HIV infections in India. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country ^[22][23] This difference is possibly due to the HIV subtype in India. India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country

Cryptococcal meningitis is an infection of the meninx (the membrane covering the brain and spinal cord) by the fungus Cryptococcus neoformans. The meninges (singular meninx) is the system of membranes which envelops the Central nervous system. The spinal cord is a long thin tubular bundle of Nerves that is an extension of the Central nervous system from the brain and is enclosed in and protected Cryptococcus (literally "Hidden Seed" is a Genus of Fungus. It can cause fevers, headache, fatigue, nausea, and vomiting. A headache ( cephalalgia in medical terminology is a condition of pain in the Head; sometimes Neck or upper back pain may also be interpreted Nausea ( Latin: Nausea, Greek:, " Sea-sickness " also called wamble) is the sensation of unease and discomfort Vomiting (also called throwing up, emesis) is the forceful expulsion of the contents of one's Stomach through the Mouth and sometimes the Patients may also develop seizures and confusion; left untreated, it can be lethal. An epileptic seizure is caused by excessive and/or hypersynchronous electrical Neuronal activity and is usually self-limiting

Tumors and malignancies

Kaposi's sarcoma

Patients with HIV infection have substantially increased incidence of several malignant cancers. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled This is primarily due to co-infection with an oncogenic DNA virus, especially Epstein-Barr virus (EBV), Kaposi's sarcoma-associated herpesvirus (KSHV), and human papillomavirus (HPV). An oncogene is a protein encoding Gene, which — when deregulated — participates in the onset and development of Cancer. A DNA virus is a Virus that has DNA as its Genetic material and replicates using a DNA-dependent DNA polymerase. The Epstein-Barr Virus ( EBV) also called Human herpesvirus 4 (HHV-4 is a Virus of the herpes family (which includes Herpes Papillomaviruses were first identified in the early 20th century when it was shown that skin Warts or Papillomas could be transmitted between individuals ^[24][25]

Kaposi's sarcoma (KS) is the most common tumor in HIV-infected patients. The appearance of this tumor in young homosexual men in 1981 was one of the first signals of the AIDS epidemic. Caused by a gammaherpes virus called Kaposi's sarcoma-associated herpes virus (KSHV), it often appears as purplish nodules on the skin, but can affect other organs, especially the mouth, gastrointestinal tract, and lungs. Gammaherpesvirinae is a subfamily of Herpesviridae distinguished by reproducing at a more variable rate than other subfamilies of Herpesviridae Kaposi's sarcoma-associated herpesvirus ( KSHV) is the eighth human Herpesvirus; its formal name according to the International Committee on Taxonomy of Viruses is In Medicine, a nodule refers to a relatively hard roughly spherical abnormal structure The mouth, buccal cavity, or oral cavity is the first portion of the Alimentary canal that receives food and begins digestion by mechanically breaking up

High-grade B cell lymphomas such as Burkitt's lymphoma, Burkitt's-like lymphoma, diffuse large B-cell lymphoma (DLBCL), and primary central nervous system lymphoma present more often in HIV-infected patients. B cells are Lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response, which is governed by Lymphoma a type of Neoplasm that originates in Lymphocytes (a type of White blood cell in the vertebrate Immune system) Burkitt lymphoma (or "Burkitt's tumor" or "Malignant lymphoma Burkitt's type" is a cancer of the lymphatic system (in particular B lymphocytes Primary CNS lymphoma is a primary intracranial tumor usually present in those with severe immunosuppression --- commonly in those with AIDS --- and represents These particular cancers often foreshadow a poor prognosis. In some cases these lymphomas are AIDS-defining. Epstein-Barr virus (EBV) or KSHV cause many of these lymphomas. The Epstein-Barr Virus ( EBV) also called Human herpesvirus 4 (HHV-4 is a Virus of the herpes family (which includes Herpes

Cervical cancer in HIV-infected women is considered AIDS-defining. Cervical cancer is Malignant Cancer of the Cervix uteri or cervical area It is caused by human papillomavirus (HPV). A human papillomavirus ( HPV) is a Papillomavirus that infects the skin and Mucous membranes of Humans Approximately 130 HPV types have been ^[26]

In addition to the AIDS-defining tumors listed above, HIV-infected patients are at increased risk of certain other tumors, such as Hodgkin's disease and anal and rectal carcinomas. Hodgkin's lymphoma, also known as Hodgkin's disease is a type of Lymphoma first described by Thomas Hodgkin in 1832 Anal cancer is a type of Cancer which arises from the Anus, the distal orifice of the Gastrointestinal tract. Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and However, the incidence of many common tumors, such as breast cancer or colon cancer, does not increase in HIV-infected patients. Breast cancer is a Cancer that starts in the cells of the Breast in women and men Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and In areas where HAART is extensively used to treat AIDS, the incidence of many AIDS-related malignancies has decreased, but at the same time malignant cancers overall have become the most common cause of death of HIV-infected patients. ^[27]

Other opportunistic infections

AIDS patients often develop opportunistic infections that present with non-specific symptoms, especially low-grade fevers and weight loss. In Medicine, low-grade fever is a continuous or fluctuating low Fever, typically defined as never exceeding 38 These include infection with Mycobacterium avium-intracellulare and cytomegalovirus (CMV). Mycobacterium avium complex (MAC is a group of Genetically -related Bacteria belonging to the genus Mycobacterium. Cytomegalovirus (CMV (from the Greek cyto-, "cell" and -megalo-, "large" is a viral CMV can cause colitis, as described above, and CMV retinitis can cause blindness. Cytomegalovirus retinitis, also known as CMV retinitis, is an inflammation of the Eye 's Retina that can lead to Blindness. Blindness is the condition of lacking Visual perception due to Physiological or Neurological factors Penicilliosis due to Penicillium marneffei is now the third most common opportunistic infection (after extrapulmonary tuberculosis and cryptococcosis) in HIV-positive individuals within the endemic area of Southeast Asia. Penicilliosis is an Infection caused by Penicillium marneffei. Penicillium species are usually regarded as unimportant in terms of causing human disease Cryptococcosis is a serious and potentially fatal Fungal disease caused by members of the Cryptococcus neoformans species complex comprising the two species ^[28]

Cause

For more details on this topic, see HIV. Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome

Scanning electron micrograph of HIV-1, colored green, budding from a cultured lymphocyte. The scanning electron microscope ( SEM) is a type of Electron microscope that images the sample surface by scanning it with a high-energy beam of Electrons A lymphocyte is a type of White blood cell in the Vertebrate Immune system.

AIDS is the most severe acceleration of infection with HIV. An infection is the detrimental Colonization of a host Organism by a foreign Species. HIV is a retrovirus that primarily infects vital organs of the human immune system such as CD4⁺ T cells (a subset of T cells), macrophages and dendritic cells. A retrovirus is any Virus belonging to the viral family Retroviridae. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor T helper cells (also known as effector T cells or Th cells) are a sub-group of Lymphocytes (a type of White blood cell or T cells belong to a group of White blood cells known as Lymphocytes, and play a central role in Cell-mediated immunity. Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that Dendritic cells (DCs are Immune cells and form part of the Mammalian Immune system. It directly and indirectly destroys CD4⁺ T cells. ^[29] Once HIV has killed so many CD4⁺ T cells that there are fewer than 200 of these cells per microliter (µL) of blood, cellular immunity is lost. The litre or liter (see spelling differences) is a unit of Volume. Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products Cell-mediated immunity is an Immune response that does not involve Antibodies or complement but rather involves the activation of Macrophages Acute HIV infection progresses over time to clinical latent HIV infection and then to early symptomatic HIV infection and later to AIDS, which is identified either on the basis of the amount of CD4⁺ T cells remaining in the blood, and/or the presence of certain infections, as noted above. In Medicine, an acute disease is a disease with either or both of a rapid onset a short course (as opposed to a chronic course ^[30]

In the absence of antiretroviral therapy, the median time of progression from HIV infection to AIDS is nine to ten years, and the median survival time after developing AIDS is only 9. In Probability theory and Statistics, a median is described as the number separating the higher half of a sample a population or a Probability distribution Following infection with HIV -1 the rate of clinical disease progression varies between individuals 2 months. ^[31] However, the rate of clinical disease progression varies widely between individuals, from two weeks up to 20 years. Many factors affect the rate of progression. These include factors that influence the body's ability to defend against HIV such as the infected person's general immune function. ^[32][33] Older people have weaker immune systems, and therefore have a greater risk of rapid disease progression than younger people. Poor access to health care and the existence of coexisting infections such as tuberculosis also may predispose people to faster disease progression. Health care is the prevention treatment and management of illness and the preservation of mental health through the services offered by the medical, Nursing Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common ^[31][34][35] The infected person's genetic inheritance plays an important role and some people are resistant to certain strains of HIV. Genetics (from Ancient Greek grc-Latn genetikos, “genitive” and that from grc-Latn genesis, “origin” a discipline of Biology, is An example of this is people with the homozygous CCR5-Δ32 variation are resistant to infection with certain strains of HIV. Zygosity refers to the genetic condition of a Zygote. In genetics zygosity describes the similarity or dissimilarity of DNA between Homologous CCR5, short for chemokine (C-C motif receptor 5, is a Chemokine receptor. In biology strain is a low-level Taxonomic rank used in three related ways ^[36] HIV is genetically variable and exists as different strains, which cause different rates of clinical disease progression. ^[37][38][39]

Sexual transmission

Sexual transmission occurs with the contact between sexual secretions of one person with the rectal, genital or oral mucous membranes of another. The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin covered in Epithelium, which are involved in Unprotected receptive sexual acts are riskier than unprotected insertive sexual acts, and the risk for transmitting HIV through unprotected anal intercourse is greater than the risk from vaginal intercourse or oral sex. However, oral sex is not entirely safe, as HIV can be transmitted through both insertive and receptive oral sex. ^[40] The risk of HIV transmission from exposure to saliva is considerably smaller than the risk from exposure to semen, one would have to swallow liters of saliva from a carrier to run a significant risk of becoming infected. For the band see Saliva (band; for the village in Azerbaijan see Səliva. Physiological aspects Internal and external fertilization Depending on the Species, spermatozoa can fertilize ^[41] Sexual assault greatly increases the risk of HIV transmission as protection is rarely employed and physical trauma to the vagina frequently occurs, facilitating the transmission of HIV. ^[42]

Other sexually transmitted infections (STI) increase the risk of HIV transmission and infection, because they cause the disruption of the normal epithelial barrier by genital ulceration and/or microulceration; and by accumulation of pools of HIV-susceptible or HIV-infected cells (lymphocytes and macrophages) in semen and vaginal secretions. A sexually transmitted disease ( STD) or venereal disease ( VD) is an illness that has a significant probability of transmission between Humans In biology and medicine epithelium is a tissue composed of cells that line the cavities and surfaces of structures throughout the body Ulcers are healing wounds that develop on the skin mucous membranes or eye A lymphocyte is a type of White blood cell in the Vertebrate Immune system. Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that Epidemiological studies from sub-Saharan Africa, Europe and North America suggest that genital ulcers, such as those caused by syphilis and/or chancroid, increase the risk of becoming infected with HIV by about four-fold. Syphilis is a Sexually transmitted disease caused by the spirochetal Bacterium Treponema pallidum pallidum. Chancroid is a Sexually transmitted infection characterized by painful sores on the genitalia There is also a significant although lesser increase in risk from STIs such as gonorrhea, Chlamydial infection and trichomoniasis, which all cause local accumulations of lymphocytes and macrophages. Gonorrhea (also gonorrhoea) caused by the bacteria Neisseria gonorrhoeae, is a common Sexually transmitted disease. Chlamydia infection (from the Greek, χλαμύδος meaning "cloak" is a common Sexually transmitted infection (STI in humans caused by the bacterium ^[43]

Transmission of HIV depends on the infectiousness of the index case and the susceptibility of the uninfected partner. Infectivity seems to vary during the course of illness and is not constant between individuals. An undetectable plasma viral load does not necessarily indicate a low viral load in the seminal liquid or genital secretions. Viral load is a measure of the severity of a viral infection and can be calculated by estimating the amount of virus in an involved body fluid However, each 10-fold increase in the level of HIV in the blood is associated with an 81% increased rate of HIV transmission. ^[43][44] Women are more susceptible to HIV-1 infection due to hormonal changes, vaginal microbial ecology and physiology, and a higher prevalence of sexually transmitted diseases. ^[45][46] People who have been infected with one strain of HIV can still be infected later on in their lives by other, more virulent strains. Virulence (also called pestiferousness) refers to the degree of Pathogenicity of a Microbe, or in other words the relative ability of a Microbe

Exposure to blood-borne pathogens

CDC poster from 1989 highlighting the threat of AIDS associated with drug use

This transmission route is particularly relevant to intravenous drug users, hemophiliacs and recipients of blood transfusions and blood products. "Shoot up" redirects here For the shooting video game genre see Shoot 'em up. Haemophilia (also spelled as hemophilia Blood transfusion is the process of transferring Blood or blood-based products from one person into the Circulatory system of another Sharing and reusing syringes contaminated with HIV-infected blood represents a major risk for infection with HIV. A syringe is a simple piston Pump consisting of a plunger that fits tightly in a tube Needle sharing is the cause of one third of all new HIV-infections in North America, China, and Eastern Europe. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National Eastern Europe is a general term that refers to the Geopolitical region encompassing the easternmost part of the European continent. The risk of being infected with HIV from a single prick with a needle that has been used on an HIV-infected person is thought to be about 1 in 150 (see table above). Post-exposure prophylaxis with anti-HIV drugs can further reduce this risk. Post-exposure prophylaxis ( PEP) is any prophylactic treatment started immediately after exposure to a pathogen (such as a disease-causing Virus) in order ^[47] This route can also affect people who give and receive tattoos and piercings. A tattoo is a permanent marking made by inserting ink into the layers of Skin to change the pigment for decorative or other reasons Body piercing is the practice of puncturing or cutting a part of the Human body, creating an opening in which jewelry may be worn Universal precautions are frequently not followed in both sub-Saharan Africa and much of Asia because of both a shortage of supplies and inadequate training. Under Universal Precautions all patients are considered to be possible carriers of blood-borne pathogens The WHO estimates that approximately 2. 5% of all HIV infections in sub-Saharan Africa are transmitted through unsafe healthcare injections. ^[48] Because of this, the United Nations General Assembly has urged the nations of the world to implement precautions to prevent HIV transmission by health workers. Membership For two articles dealing with membership in the General Assembly see General Assembly members ^[49]

The risk of transmitting HIV to blood transfusion recipients is extremely low in developed countries where improved donor selection and HIV screening is performed. Blood transfusion is the process of transferring Blood or blood-based products from one person into the Circulatory system of another However, according to the WHO, the overwhelming majority of the world's population does not have access to safe blood and between 5% and 10% of the world's HIV infections come from transfusion of infected blood and blood products. ^[50]

Perinatal transmission

The transmission of the virus from the mother to the child can occur in utero during the last weeks of pregnancy and at childbirth. For the Nirvana album see In Utero. In utero is a Latin term literally meaning "in the Uterus " In the absence of treatment, the transmission rate between a mother and her child during pregnancy, labor and delivery is 25%. However, when the mother takes antiretroviral therapy and gives birth by caesarean section, the rate of transmission is just 1%. A Caesarean section (or Cesarean section in American English) also known as C-section, is a form of Childbirth in which a surgical ^[51] The risk of infection is influenced by the viral load of the mother at birth, with the higher the viral load, the higher the risk. Breastfeeding also increases the risk of transmission by about 4 %. Breastfeeding is the feeding of an Infant or young Child with Breast milk directly from human Breasts, not from a Baby bottle or other ^[52]

Misconceptions

Main article: HIV and AIDS misconceptions

A number of misconceptions have arisen surrounding HIV/AIDS. The spread of HIV and AIDS has affected millions of people worldwide According to the "2006 AIDS Epidemic Update" published by the UNAIDS / World Health Three of the most common are that AIDS can spread through casual contact, that sexual intercourse with a virgin will cure AIDS, and that HIV can infect only homosexual men and drug users. Other misconceptions are that any act of anal intercourse between gay men can lead to AIDS infection, and that open discussion of homosexuality and HIV in schools will lead to increased rates of homosexuality and AIDS. ^[53]

Pathophysiology

The pathophysiology of AIDS is complex, as is the case with all syndromes. In Medicine and Psychology, the term syndrome refers to the association of several clinically recognizable features signs (observed by a physician ^[54] Ultimately, HIV causes AIDS by depleting CD4⁺ T helper lymphocytes. This weakens the immune system and allows opportunistic infections. An opportunistic infection is an infection caused by Pathogens that usually do not cause disease in a healthy Immune system. T lymphocytes are essential to the immune response and without them, the body cannot fight infections or kill cancerous cells. The mechanism of CD4⁺ T cell depletion differs in the acute and chronic phases. ^[55] During the acute phase, HIV-induced cell lysis and killing of infected cells by cytotoxic T cells accounts for CD4⁺ T cell depletion, although apoptosis may also be a factor. A cytotoxic T cell (also known as TC, CTL T-Killer cell cytolytic T cell CD8+ T-cells or killer T cell) belongs to a sub-group of T lymphocytes During the chronic phase, the consequences of generalized immune activation coupled with the gradual loss of the ability of the immune system to generate new T cells appear to account for the slow decline in CD4⁺ T cell numbers.

Although the symptoms of immune deficiency characteristic of AIDS do not appear for years after a person is infected, the bulk of CD4⁺ T cell loss occurs during the first weeks of infection, especially in the intestinal mucosa, which harbors the majority of the lymphocytes found in the body. ^[56] The reason for the preferential loss of mucosal CD4⁺ T cells is that a majority of mucosal CD4⁺ T cells express the CCR5 coreceptor, whereas a small fraction of CD4⁺ T cells in the bloodstream do so. ^[57] HIV seeks out and destroys CCR5 expressing CD4⁺ cells during acute infection. A vigorous immune response eventually controls the infection and initiates the clinically latent phase. However, CD4⁺ T cells in mucosal tissues remain depleted throughout the infection, although enough remain to initially ward off life-threatening infections.

Continuous HIV replication results in a state of generalized immune activation persisting throughout the chronic phase. ^[58] Immune activation, which is reflected by the increased activation state of immune cells and release of proinflammatory cytokines, results from the activity of several HIV gene products and the immune response to ongoing HIV replication. Cytokines are a category of signalling Proteins and Glycoproteins that like Hormones and Neurotransmitters, are used extensively in cellular Another cause is the breakdown of the immune surveillance system of the mucosal barrier caused by the depletion of mucosal CD4⁺ T cells during the acute phase of disease. ^[59] This results in the systemic exposure of the immune system to microbial components of the gut’s normal flora, which in a healthy person is kept in check by the mucosal immune system. The activation and proliferation of T cells that results from immune activation provides fresh targets for HIV infection. However, direct killing by HIV alone cannot account for the observed depletion of CD4⁺ T cells since only 0. 01-0. 10% of CD4⁺ T cells in the blood are infected. A major cause of CD4⁺ T cell loss appears to result from their heightened susceptibility to apoptosis when the immune system remains activated. Although new T cells are continuously produced by the thymus to replace the ones lost, the regenerative capacity of the thymus is slowly destroyed by direct infection of its thymocytes by HIV. In Human anatomy, the thymus is an organ located in the upper Anterior portion of the chest cavity just behind the Sternum. Thymocytes are T cell precursors which develop in the Thymus. Eventually, the minimal number of CD4⁺ T cells necessary to maintain a sufficient immune response is lost, leading to AIDS

Cells affected

The virus, entering through which ever route, acts primarily on the following cells:^[60]

1. Lymphoreticular system:
   1. CD₄+ T-Helper cells
   2. CD₄+ Macrophages
   3. CD₄+ Monocytes
   4. B-lymphocytes
2. Certain endothelial cells
3. Central nervous system:
   1. Microglia of the nervous system
   2. Astrocytes
   3. Oligodendrocytes
   4. Neurones - indirectly by the action of cytokines and the gp-120

The effect

The virus has cytopathic effects but how it does it is still not quite clear. A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable The reticuloendothelial system ( RES) part of the Immune system, consists of the phagocytic cells located in Reticular connective tissue, primarily T helper cells (also known as effector T cells or Th cells) are a sub-group of Lymphocytes (a type of White blood cell or Macrophages ( Greek: "big eaters" from makros "large" + phagein "eat" ( Mø) are cells within the tissues that Monocyte is a type of Leukocyte, part of the Human body 's Immune system. B cells are Lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response, which is governed by The endothelium is the thin layer of cells that line the interior surface of Blood vessels forming an interface between circulating Blood in the In Vertebrates the central nervous system ( CNS) is the part of the Nervous system which is enclosed in the Meninges. Microglia are a type of Glial cell that acts as the first and main form of active immune defense in the Central nervous system (CNS Astrocytes (also known collectively as astroglia) are characteristic star-shaped glial cells in the Brain and Spinal cord. Origin Oligodendroglia arise during development from an Oligodendrocyte precursor cell, which can be identified by its expression of a number of Antigens, including Neurons (ˈnjuːɹɒn also known as neurones and nerve cells) are responsive cells in the Nervous system that process and transmit information Cytokines are a category of signalling Proteins and Glycoproteins that like Hormones and Neurotransmitters, are used extensively in cellular gp120 is a Glycoprotein exposed on the surface of the HIV envelope. A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable Cytopathic effect (CPE refers to degenerative changes in cells (especially in Tissue culture) associated with the multiplication of certain Viruses It can remain inactive in these cells for long periods, though. This effect is hypothesized to be due to the CD₄-gp120 interaction. ^[61]

• The most prominent effect of the HIV virus is its T-helper cell suppression and lysis. The cell is simply killed off or deranged to the point of being function-less (they do not respond to foreign antigens). An antigen (from antibody-generating) or immunogen is a substance that prompts the generation of Antibodies and can cause an immune response The infected B-cells can not produce enough antibodies either. Thus the immune system collapses leading to the familiar AIDS complications, like infections and neoplasms (vide supra).
• Infection of the cells of the CNS cause acute aseptic meningitis, subacute encephalitis, vacuolar myelopathy and peripheral neuropathy. Aseptic meningitis, or sterile meningitis is a condition in which the layers lining of the brain or Meninges, become inflamed and a Pyogenic Bacterial Encephalitis is an acute Inflammation of the Brain, commonly caused by a viral Infection. Peripheral neuropathy is the term for damage to Nerves of the Peripheral nervous system, which may be caused either by diseases of the Nerve or from the Later it leads to even AIDS dementia complex.
• The CD₄-gp120 interaction (vide supra) is also permissive to other viruses like Cytomegalovirus, Hepatitis virus, Herpes simplex virus, etc. Cytomegalovirus (CMV (from the Greek cyto-, "cell" and -megalo-, "large" is a viral Hepatitis (plural hepatitides) implies injury to the Liver characterized by the presence of Inflammatory cells in the tissue of Herpes simplex is a Viral disease caused by Herpes simplex viruses both herpes simplex virus 1 (HSV-1 and herpes simplex virus 2 (HSV-2 cause herpes simplex These viruses lead to further cell damage i. e. cytopathy.

Molecular basis

For details, see:

• Structure and genome of HIV,
• HIV replication cycle
• HIV tropism

Diagnosis

The diagnosis of AIDS in a person infected with HIV is based on the presence of certain signs or symptoms. The Genome and Proteins of HIV have been the subject of extensive research since the discovery of the virus in 1983 Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome HIV tropism refers to the Cell type that the Human immunodeficiency virus (HIV infects and replicates in Since June 5, 1981, many definitions have been developed for epidemiological surveillance such as the Bangui definition and the 1994 expanded World Health Organization AIDS case definition. Events 70 - Titus and his Roman Legions breach the middle wall of Jerusalem in the Siege of Jerusalem Year 1981 ( MCMLXXXI) was a Common year starting on Thursday (link displays the 1981 Epidemiology is the study of factors affecting the Health and Illness of populations and serves as the foundation and Logic of interventions made in the The 1985 World Health Organization AIDS surveillance case definition was developed in October 1985, at a conference of Public health officials including representatives The 1994 expanded World Health Organization AIDS case definition came around through the developments in the understanding of the spectrum of severe HIV-related illness both in developed However, clinical staging of patients was not an intended use for these systems as they are neither sensitive, nor specific. In developing countries, the World Health Organization staging system for HIV infection and disease, using clinical and laboratory data, is used and in developed countries, the Centers for Disease Control (CDC) Classification System is used. The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated

WHO disease staging system

Main article: WHO Disease Staging System for HIV Infection and Disease

In 1990, the World Health Organization (WHO) grouped these infections and conditions together by introducing a staging system for patients infected with HIV-1. WHO Disease Staging System for HIV Infection and Disease was first produced in 1990 by the World Health Organisation and updated in September 2005 ^[62] An update took place in September 2005. Most of these conditions are opportunistic infections that are easily treatable in healthy people. An opportunistic infection is an infection caused by Pathogens that usually do not cause disease in a healthy Immune system.

• Stage I: HIV infection is asymptomatic and not categorized as AIDS
• Stage II: includes minor mucocutaneous manifestations and recurrent upper respiratory tract infections
• Stage III: includes unexplained chronic diarrhea for longer than a month, severe bacterial infections and pulmonary tuberculosis
• Stage IV: includes toxoplasmosis of the brain, candidiasis of the esophagus, trachea, bronchi or lungs and Kaposi's sarcoma; these diseases are indicators of AIDS. The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin covered in Epithelium, which are involved in The Upper respiratory tract refers to the following parts of the Respiratory system: Nose and Oral cavity Throat In Medicine, a chronic disease is a Disease that is long-lasting or recurrent In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea lung is the essential Respiration organ in air-breathing Animals including most Tetrapods a few Fish and a few Snails The most primitive Toxoplasmosis is a Parasitic disease caused by the Protozoan Toxoplasma gondii. The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain Candidiasis, commonly called yeast infection or thrush, is a Fungal infection (mycosis of any of the Candida species of which The esophagus or oesophagus (see American and British English spelling differences) sometimes known as the gullet, is an organ in The traceartes, or windpipe, is a tube that has an inner diameter of about 20-25 mm and a length of about 10-16 cm in humans A bronchus (plural bronchi, adjective bronchial) is a caliber of airway in the Respiratory tract that conducts air into the Lungs No Gas lung is the essential Respiration organ in air-breathing Animals including most Tetrapods a few Fish and a few Snails The most primitive Kaposi's sarcoma (KS is a tumor caused by Human herpesvirus 8 ( HHV8) also known as Kaposi's sarcoma-associated herpesvirus (KSHV

CDC classification system

Main article: CDC Classification System for HIV Infection

There are two main definitions for AIDS, both produced by the Centers for Disease Control and Prevention (CDC). This Medical classification system is how the United States agency the Centers for Disease Control and Prevention (CDC classifies HIV Disease The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated The older definition is to referring to AIDS using the diseases that were associated with it, for example, lymphadenopathy, the disease after which the discoverers of HIV originally named the virus. Lymphadenopathy is a term meaning "disease of the Lymph nodes. ^[63][64] In 1993, the CDC expanded their definition of AIDS to include all HIV positive people with a CD4⁺ T cell count below 200 per µL of blood or 14% of all lymphocytes. A lymphocyte is a type of White blood cell in the Vertebrate Immune system. ^[65] The majority of new AIDS cases in developed countries use either this definition or the pre-1993 CDC definition. The term developed country, or advanced country, is used to categorize countries with developed Economies in which the tertiary and quaternary sectors The AIDS diagnosis still stands even if, after treatment, the CD4⁺ T cell count rises to above 200 per µL of blood or other AIDS-defining illnesses are cured.

HIV test

Main article: HIV test

Many people are unaware that they are infected with HIV. HIV tests are used to detect the presence of the Human immunodeficiency virus in serum, Saliva, or Urine. ^[66] Less than 1% of the sexually active urban population in Africa has been tested, and this proportion is even lower in rural populations. Furthermore, only 0. 5% of pregnant women attending urban health facilities are counseled, tested or receive their test results. Again, this proportion is even lower in rural health facilities. ^[66] Therefore, donor blood and blood products used in medicine and medical research are screened for HIV.

HIV tests are usually performed on venous blood. Many laboratories use fourth generation screening tests which detect anti-HIV antibody (IgG and IgM) and the HIV p24 antigen. The detection of HIV antibody or antigen in a patient previously known to be negative is evidence of HIV infection. Individuals whose first specimen indicates evidence of HIV infection will have a repeat test on a second blood sample to confirm the results. The window period (the time between initial infection and the development of detectable antibodies against the infection) can vary since it can take 3–6 months to seroconvert and to test positive. In medicine the window period for a test designed to detect a specific Disease (particularly infectious disease is the time between first Infection and when the Seroconversion is the development of detectable specific Antibodies to Microorganisms in the blood serum as a result of Infection or Immunization Detection of the virus using polymerase chain reaction (PCR) during the window period is possible, and evidence suggests that an infection may often be detected earlier than when using a fourth generation EIA screening test. Positive results obtained by PCR are confirmed by antibody tests. ^[67] Routinely used HIV tests for infection in neonates, born to HIV-positive mothers, have no value because of the presence of maternal antibody to HIV in the child's blood. HIV infection can only be diagnosed by PCR, testing for HIV pro-viral DNA in the children's lymphocytes. A lymphocyte is a type of White blood cell in the Vertebrate Immune system. ^[68]

Prevention

The three main transmission routes of HIV are sexual contact, exposure to infected body fluids or tissues, and from mother to fetus or child during perinatal period. Human sexual behavior or different human sexual practices encompass a wide range of activities such as strategies to find or attract partners ( Mating and display A fetus (or foetus or fœtus) is a developing Mammal or other Viviparous Vertebrate, after the Embryonic stage and Perinatal defines the period occurring around the time of birth (5 months before and 1 month after It is possible to find HIV in the saliva, tears, and urine of infected individuals, but there are no recorded cases of infection by these secretions, and the risk of infection is negligible. For the band see Saliva (band; for the village in Azerbaijan see Səliva. Tears are the liquid product of a process of lacrimation to clean and lubricate the Eyes The word lacrimation may also be used in a medical or literary sense Urine is a liquid waste product of the body secreted by the Kidneys by a process of filtration from Blood and Excreted through the Urethra. ^[76]

Sexual contact

The majority of HIV infections are acquired through unprotected sexual relations between partners, one of whom has HIV. Bareback is a term that originated in Gay slang to describe acts of Unprotected sex, especially Anal sex. The primary mode of HIV infection worldwide is through sexual contact between members of the opposite sex. ^[77][78][79] During a sexual act, only male or female condoms can reduce the chances of infection with HIV and other STDs and the chances of becoming pregnant. A condom is a device most commonly used during Sexual intercourse. Pregnancy ( Latin graviditas) is the carrying of one or more offspring known as a Fetus or Embryo, inside the Uterus of a Female The best evidence to date indicates that typical condom use reduces the risk of heterosexual HIV transmission by approximately 80% over the long-term, though the benefit is likely to be higher if condoms are used correctly on every occasion. Heterosexuality refers to sexual behavior with or attraction to people of the opposite sex or to a heterosexual orientation ^[80] The male latex condom, if used correctly without oil-based lubricants, is the single most effective available technology to reduce the sexual transmission of HIV and other sexually transmitted infections. LaTeX (ˈleɪtɛ Manufacturers recommend that oil-based lubricants such as petroleum jelly, butter, and lard not be used with latex condoms, because they dissolve the latex, making the condoms porous. Petroleum jelly, petrolatum or soft paraffin is a Semi-solid mixture of Hydrocarbons (with Carbon numbers mainly higher than 25 Lard is pig Fat in both its rendered and unrendered forms Lard was commonly used in many cuisines as a Cooking fat or Shortening LaTeX (ˈleɪtɛ Porosity is a measure of the void spaces in a material and is measured as a fraction between 0–1 or as a Percentage between 0–100% If necessary, manufacturers recommend using water-based lubricants. Water is a common Chemical substance that is essential for the survival of all known forms of Life. Oil-based lubricants can however be used with polyurethane condoms. A polyurethane, commonly abbreviated PU, is any Polymer consisting of a chain of organic units joined by urethane links ^[81]

The female condom is an alternative to the male condom and is made from polyurethane, which allows it to be used in the presence of oil-based lubricants. A female condom is a device that is used during Sexual intercourse to prevent pregnancy and transmission of Sexually transmitted infections (STIs—such as A polyurethane, commonly abbreviated PU, is any Polymer consisting of a chain of organic units joined by urethane links They are larger than male condoms and have a stiffened ring-shaped opening, and are designed to be inserted into the vagina. The female condom contains an inner ring, which keeps the condom in place inside the vagina – inserting the female condom requires squeezing this ring. However, at present availability of female condoms is very low and the price remains prohibitive for many women. Preliminary studies suggest that, where female condoms are available, overall protected sexual acts increase relative to unprotected sexual acts, making them an important HIV prevention strategy. ^[82]

Studies on couples where one partner is infected show that with consistent condom use, HIV infection rates for the uninfected partner are below 1% per year. ^[83] Prevention strategies are well-known in developed countries, however, recent epidemiological and behavioral studies in Europe and North America have suggested that a substantial minority of young people continue to engage in high-risk practices and that despite HIV/AIDS knowledge, young people underestimate their own risk of becoming infected with HIV. ^[84]

Randomized controlled trials have shown that male circumcision lowers the risk of HIV infection among heterosexual men by up to 60%. A randomized controlled trial (RCT is a type of scientific Experiment most commonly used in testing the Efficacy or Effectiveness of Healthcare Male circumcision is the removal of some or all of the Foreskin (prepuce from the Penis. ^[85] It is expected that this procedure will be actively promoted in many of the countries affected by HIV, although doing so will involve confronting a number of practical, cultural and attitudinal issues. Some experts fear that a lower perception of vulnerability among circumcised men may result in more sexual risk-taking behavior, thus negating its preventive effects. ^[86]

Exposure to infected body fluids

Health care workers can reduce exposure to HIV by employing precautions to reduce the risk of exposure to contaminated blood. These precautions include barriers such as gloves, masks, protective eyeware or shields, and gowns or aprons which prevent exposure of the skin or mucous membranes to blood borne pathogens. Frequent and thorough washing of the skin immediately after being contaminated with blood or other bodily fluids can reduce the chance of infection. Finally, sharp objects like needles, scalpels and glass, are carefully disposed of to prevent needlestick injuries with contaminated items. ^[87] Since intravenous drug use is an important factor in HIV transmission in developed countries, harm reduction strategies such as needle-exchange programmes are used in attempts to reduce the infections caused by drug abuse. Harm reduction is a Philosophy of Public health, intended to be a progressive alternative to the prohibition of certain potentially dangerous A hypodermic needle-exchange program is a sometimes controversial Social policy, based on the philosophy of Harm reduction where injection ^[88][89]

Mother-to-child transmission (MTCT)

Current recommendations state that when replacement feeding is acceptable, feasible, affordable, sustainable and safe, HIV-infected mothers should avoid breast-feeding their infant. However, if this is not the case, exclusive breast-feeding is recommended during the first months of life and discontinued as soon as possible. ^[90]

Treatment

See also HIV Treatment and Antiretroviral drug. Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome

Abacavir – a nucleoside analog reverse transcriptase inhibitors (NARTIs or NRTIs)

The chemical structure of Abacavir

There is currently no vaccine or cure for HIV or AIDS. Abacavir ( ABC) is a Nucleoside analog Reverse transcriptase inhibitor (NRTI used to treat HIV and AIDS. An HIV vaccine is a hypothetical Vaccine against HIV, the etiological agent of AIDS. Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome The only known methods of prevention are based on avoiding exposure to the virus or, failing that, an antiretroviral treatment directly after a highly significant exposure, called post-exposure prophylaxis (PEP). Post-exposure prophylaxis ( PEP) is any prophylactic treatment started immediately after exposure to a pathogen (such as a disease-causing Virus) in order ^[91] PEP has a very demanding four week schedule of dosage. It also has very unpleasant side effects including diarrhea, malaise, nausea and fatigue. In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea Malaise is a feeling of general discomfort or uneasiness an "out of sorts" feeling often the first indication of an infection or other disease Nausea ( Latin: Nausea, Greek:, " Sea-sickness " also called wamble) is the sensation of unease and discomfort ^[92]

Antiviral therapy

Current treatment for HIV infection consists of highly active antiretroviral therapy, or HAART. ^[93] This has been highly beneficial to many HIV-infected individuals since its introduction in 1996 when the protease inhibitor-based HAART initially became available. ^[9] Current optimal HAART options consist of combinations (or "cocktails") consisting of at least three drugs belonging to at least two types, or "classes," of antiretroviral agents. Typical regimens consist of two nucleoside analogue reverse transcriptase inhibitors (NARTIs or NRTIs) plus either a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor (NNRTI). Reverse transcriptase inhibitors (RTIs are a class of Antiretroviral drug used to treat HIV infection Tumors, and Cancer. For natural protease inhibitors please see Protease inhibitor (biology Protease inhibitors (PIs are a class of Medications used Reverse transcriptase inhibitors (RTIs are a class of Antiretroviral drug used to treat HIV infection Tumors, and Cancer. Because HIV disease progression in children is more rapid than in adults, and laboratory parameters are less predictive of risk for disease progression, particularly for young infants, treatment recommendations are more aggressive for children than for adults. ^[94] In developed countries where HAART is available, doctors assess the viral load, rapidity in CD4 decline, and patient readiness while deciding when to recommend initiating treatment. Viral load is a measure of the severity of a viral infection and can be calculated by estimating the amount of virus in an involved body fluid ^[95]

HAART allows the stabilization of the patient’s symptoms and viremia, but it neither cures the patient of HIV, nor alleviates the symptoms, and high levels of HIV-1, often HAART resistant, return once treatment is stopped. ^[96][97] Moreover, it would take more than the lifetime of an individual to be cleared of HIV infection using HAART. ^[98] Despite this, many HIV-infected individuals have experienced remarkable improvements in their general health and quality of life, which has led to the plummeting of HIV-associated morbidity and mortality. ^{[99][100][101]} In the absence of HAART, progression from HIV infection to AIDS occurs at a median of between nine to ten years and the median survival time after developing AIDS is only 9. In Probability theory and Statistics, a median is described as the number separating the higher half of a sample a population or a Probability distribution 2 months. ^[31] HAART is thought to increase survival time by between 4 and 12 years. ^[102][103]

For some patients, which can be more than fifty percent of patients, HAART achieves far less than optimal results, due to medication intolerance/side effects, prior ineffective antiretroviral therapy and infection with a drug-resistant strain of HIV. Non-adherence and non-persistence with therapy are the major reasons why some people do not benefit from HAART. ^[104] The reasons for non-adherence and non-persistence are varied. Major psychosocial issues include poor access to medical care, inadequate social supports, psychiatric disease and drug abuse. HAART regimens can also be complex and thus hard to follow, with large numbers of pills taken frequently. ^{[105][106][107]} Side effects can also deter people from persisting with HAART, these include lipodystrophy, dyslipidaemia, diarrhoea, insulin resistance, an increase in cardiovascular risks and birth defects. Lipodystrophy is a medical condition characterized by abnormal or degenerative conditions of the body's Adipose tissue Dyslipidemia is a disruption in the amount of Lipids in the blood In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea Insulin resistance is the condition in which normal amounts of Insulin are inadequate to produce a normal Insulin response from Fat, Muscle This is an article about the rock music band "Circulatory System" A congenital disorder is a disease or disorder that is present at birth ^[108] Anti-retroviral drugs are expensive, and the majority of the world's infected individuals do not have access to medications and treatments for HIV and AIDS.

Future research

It has been postulated that only a vaccine can halt the pandemic because a vaccine would possibly cost less, thus being affordable for developing countries, and would not require daily treatments. However, even after almost 30 years of research, HIV-1 remains a difficult target for a vaccine. ^[109]

Research to improve current treatments includes decreasing side effects of current drugs, further simplifying drug regimens to improve adherence, and determining the best sequence of regimens to manage drug resistance. A number of studies have shown that measures to prevent opportunistic infections can be beneficial when treating patients with HIV infection or AIDS. Vaccination against hepatitis A and B is advised for patients who are not infected with these viruses and are at risk of becoming infected. Vaccination is the administration of Antigenic material (the Vaccine) to produce immunity to a disease Hepatitis (plural hepatitides) implies injury to the Liver characterized by the presence of Inflammatory cells in the tissue of ^[110] Patients with substantial immunosuppression are also advised to receive prophylactic therapy for Pneumocystis jiroveci pneumonia (PCP), and many patients may benefit from prophylactic therapy for toxoplasmosis and Cryptococcus meningitis as well. Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Toxoplasmosis is a Parasitic disease caused by the Protozoan Toxoplasma gondii. Cryptococcus (literally "Hidden Seed" is a Genus of Fungus. Meningitis is Inflammation of the protective membranes covering the Brain and Spinal cord, known collectively as the Meninges. ^[92]

Alternative medicine

Various forms of alternative medicine have been used to treat symptoms or alter the course of the disease. The term alternative medicine, as used in the modern western world encompasses any healing practice "that does not fall within the realm of conventional Medicine. ^[111] Acupuncture has been used to alleviate some symptoms, such peripheral neuropathy, but cannot cure the HIV infection. History Antiquity In China, the practice of acupuncture can perhaps be traced as far back as ^[112] Several randomized clinical trials testing the effect of herbal medicines have shown that there is no evidence that these herbs have any effect on the progression of the disease, but may instead produce serious side-effects. ^[113]

Some data suggest that multivitamin and mineral supplements might reduce HIV disease progression in adults, although there is no conclusive evidence on if they reduce mortality among people with good nutritional status. A multivitamin is a preparation intended to supplement a human diet with Vitamins Dietary minerals and other nutritional elements ^[114] Vitamin A supplementation in children probably has some benefit. Vitamin A refers to a family of similarly shaped molecules the Retinoids. ^[114] Daily doses of selenium can suppress HIV viral burden with an associated improvement of the CD4 count. Selenium (səˈliniəm is a Chemical element with the Atomic number 34 represented by the chemical symbol Se, an atomic mass of 78 Selenium can be used as an adjunct therapy to standard antiviral treatments, but cannot itself reduce mortality and morbidity. ^[115]

Current studies indicate that that alternative medicine therapies have little effect on the mortality or morbidity of the disease, but may improve the quality of life of individuals afflicted with AIDS. The psychological benefits of these therapies are the most important use. ^[111]

Epidemiology

Main article: AIDS pandemic

Estimated prevalence of HIV among young adults (15-49) per country at the end of 2005

The AIDS pandemic can also be seen as several epidemics of separate subtypes; the major factors in its spread are sexual transmission and vertical transmission from mother to child at birth and through breast milk. Acquired Immune Deficiency Syndrome ( AIDS) has led to the deaths of more than 25 million people since it was first recognized in 1981, making it one of ^[4] Despite recent, improved access to antiretroviral treatment and care in many regions of the world, the AIDS pandemic claimed an estimated 2. 1 million (range 1. 9–2. 4 million) lives in 2007 of which an estimated 330,000 were children under 15 years. ^[5] Globally, an estimated 33. 2 million people lived with HIV in 2007, including 2. 5 million children. An estimated 2. 5 million (range 1. 8–4. 1 million) people were newly infected in 2007, including 420,000 children. ^[5]

Sub-Saharan Africa remains by far the worst affected region. Acquired Immune Deficiency Syndrome ( AIDS) has led to the deaths of more than 25 million people since it was first recognized in 1981, making it one of In 2007 it contained an estimated 68% of all people living with AIDS and 76% of all AIDS deaths, with 1. 7 million new infections bringing the number of people living with HIV to 22. 5 million, and with 11. 4 million AIDS orphans living in the region. Unlike other regions, most people living with HIV in sub-Saharan Africa in 2007 (61%) were women. Adult prevalence in 2007 was an estimated 5. In Epidemiology, the prevalence of a Disease in a Statistical population is defined as the total number of cases of the disease in the population at a given 0%, and AIDS continued to be the single largest cause of mortality in this region. ^[5] South Africa has the largest population of HIV patients in the world, followed by Nigeria and India. The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa Nigeria, officially named the Federal Republic of Nigeria, is a federal Constitutional republic comprising thirty-six states and one Federal India, officially the Republic of India (भारत गणराज्य inc-Latn Bhārat Gaṇarājya; see also other Indian languages) is a country ^[116] South & South East Asia are second worst affected; in 2007 this region contained an estimated 18% of all people living with AIDS, and an estimated 300,000 deaths from AIDS. Acquired Immune Deficiency Syndrome ( AIDS) has led to the deaths of more than 25 million people since it was first recognized in 1981, making it one of ^[5] India has an estimated 2. 5 million infections and an estimated adult prevalence of 0. 36%. ^[5] Life expectancy has fallen dramatically in the worst-affected countries; for example, in 2006 it was estimated that it had dropped from 65 to 35 years in Botswana. Life expectancy is the average number of years of life remaining at a given age The Republic of Botswana (Lefatshe la Botswana is a Landlocked nation in Southern Africa. ^[4]

Prognosis

Without treatment, the net median survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype,^[5] and the median survival rate after diagnosis of AIDS in resource-limited settings where treatment is not available ranges between 6 and 19 months, depending on the study. ^[117] In areas where it is widely available, the development of HAART as effective therapy for HIV infection and AIDS reduced the death rate from this disease by 80%, and raised the life expectancy for a newly-diagnosed HIV-infected person to about 20 years. ^[118]

As new treatments continue to be developed and because HIV continues to evolve resistance to treatments, estimates of survival time are likely to continue to change. eVolution is the third Album by eLDee, it was due to be released in 2008 Without antiretroviral therapy, death normally occurs within a year. ^[31] Most patients die from opportunistic infections or malignancies associated with the progressive failure of the immune system. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled ^[119] The rate of clinical disease progression varies widely between individuals and has been shown to be affected by many factors such as host susceptibility and immune function^[32][33][36] health care and co-infections,^[31][119] as well as which particular strain of the virus is involved. ^{[38][120][121]}

History

Main article: AIDS origin

AIDS was first reported June 5, 1981, when the U. HIV, the infectious agent that causes AIDS, is thought to have originated in non-human Primates in sub-Saharan Africa and to have been transferred to humans during Events 70 - Titus and his Roman Legions breach the middle wall of Jerusalem in the Siege of Jerusalem Year 1981 ( MCMLXXXI) was a Common year starting on Thursday (link displays the 1981 S. Centers for Disease Control and Prevention recorded a cluster of Pneumocystis carinii pneumonia (now still classified as PCP but known to be caused by Pneumocystis jirovecii) in five homosexual men in Los Angeles. The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Pneumocystis pneumonia ( PCP) is a form of Pneumonia caused by the yeast-like Fungus, Pneumocystis jirovecii (Jirovecii is pronounced Los Angeles (lɑˈsændʒələs los ˈaŋxeles in Spanish) is the largest City in the state of California and the American West ^[122] In the beginning, the Centers for Disease Control and Prevention (CDC) did not have an official name for the disease, often referring to it by way of the diseases that were associated with it, for example, lymphadenopathy, the disease after which the discoverers of HIV originally named the virus. The Centers for Disease Control and Prevention (or CDC) is an agency of the United States Department of Health and Human Services based in unincorporated Lymphadenopathy is a term meaning "disease of the Lymph nodes. ^[63][64] They also used Kaposi's Sarcoma and Opportunistic Infections, the name by which a task force had been set up in 1981. ^[123] In the general press, the term GRID, which stood for Gay-related immune deficiency, had been coined. Gay-related immune deficiency ( GRID) (sometimes informally called the gay plague or GRIDS) was an alternative name for AIDS, proposed in 1982 ^[124] However, after determining that AIDS was not isolated to the homosexual community,^[123] the term GRID became misleading and AIDS was introduced at a meeting in July 1982. Homosexuality refers to sexual behavior with or attraction to people of the same sex or to a Homosexual orientation. ^[125] By September 1982 the CDC started using the name AIDS, and properly defined the illness. ^[126]

A more controversial theory known as the OPV AIDS hypothesis suggests that the AIDS epidemic was inadvertently started in the late 1950s in the Belgian Congo by Hilary Koprowski's research into a poliomyelitis vaccine. See also AIDS origin The oral polio vaccine (OPV AIDS hypothesis argues that the AIDS Pandemic originated from live Polio vaccines prepared The Belgian Congo ( Dutch: Belgisch Kongo French: Congo Belge German: Belgisch Kongo was the formal title of present-day Democratic Republic Hilary Koprowski (born December 5, 1916, in Warsaw, Poland) is a Polish Virologist and Immunologist, and inventor Poliomyelitis, often called polio or infantile paralysis, is an acute viral Infectious disease spread from person to person primarily via A vaccine is a biological preparation which is used to establish or improve immunity to a particular disease ^[127][128] According to scientific consensus, this scenario is not supported by the available evidence. Scientific consensus is the collective judgement position and Opinion of the community of Scientists in a particular field of Science at a particular ^{[129][130][131]}

A recent study states that HIV probably moved from Africa to Haiti and then entered the United States around 1969. Haiti ( English: ˈheɪ·tiː or haɪ·ˈjiː·tiː French Haïti a·i·ti Haitian Creole: ^[132]

Society and culture

Stigma

Ryan White became a poster child for HIV after being expelled from school because of his infection. Ryan Wayne White (December 6 1971 – April 8 1990 was an American teenager from Kokomo Indiana who became a national Poster child for HIV

AIDS stigma exists around the world in a variety of ways, including ostracism, rejection, discrimination and avoidance of HIV infected people; compulsory HIV testing without prior consent or protection of confidentiality; violence against HIV infected individuals or people who are perceived to be infected with HIV; and the quarantine of HIV infected individuals. Shunning is the act of deliberately avoiding association with and habitually keeping away from an individual or group Unlike most discrimination policies discrimination between, which is the discernment of qualities and recognition of the differences focused here discrimination against is Consent as a term of jurisprudence is a possible defence (an Excuse or justification against civil or criminal liability For other uses see Quarantine (disambiguation Quarantine is voluntary or compulsory isolation typically to contain the spread of something ^[133] Stigma-related violence or the fear of violence prevents many people from seeking HIV testing, returning for their results, or securing treatment, possibly turning what could be a manageable chronic illness into a death sentence and perpetuating the spread of HIV. ^[134]

AIDS stigma has been further divided into the following three categories:

• Instrumental AIDS stigma—a reflection of the fear and apprehension that are likely to be associated with any deadly and transmissible illness. ^[135]
• Symbolic AIDS stigma—the use of HIV/AIDS to express attitudes toward the social groups or lifestyles perceived to be associated with the disease. ^[135]
• Courtesy AIDS stigma—stigmatization of people connected to the issue of HIV/AIDS or HIV- positive people. ^[136]

Often, AIDS stigma is expressed in conjunction with one or more other stigmas, particularly those associated with homosexuality, bisexuality, promiscuity, and intravenous drug use. Homosexuality refers to sexual behavior with or attraction to people of the same sex or to a Homosexual orientation. Bisexuality refers to sexual behavior with or attraction to people of both sexes or to a bisexual orientation Promiscuity refers to sexual behavior of a man or woman who casually has sex with many partners "Shoot up" redirects here For the shooting video game genre see Shoot 'em up.

In many developed countries, there is an association between AIDS and homosexuality or bisexuality, and this association is correlated with higher levels of sexual prejudice such as anti-homosexual attitudes. The term developed country, or advanced country, is used to categorize countries with developed Economies in which the tertiary and quaternary sectors BenPhelpsJPG|thumb|right|Westboro Baptist Church picket signs with Ben Phelps grandson of Fred Phelps ^[137] There is also a perceived association between AIDS and all male-male sexual behavior, including sex between uninfected men. ^[135]

Economic impact

Main article: Economic impact of AIDS

Changes in life expectancy in some hard-hit African countries. HIV and AIDS affects Economic growth by reducing the availability of Human capital.                      Botswana                     Zimbabwe                     Kenya                     South Africa                     Uganda

HIV and AIDS affects economic growth by reducing the availability of human capital. Economic growth is the increase in the amount of the goods and services produced by an economy over time Human capital refers to the stock of skills and knowledge embodied in the ability to perform labor so as to produce Economic value. ^[6] Without proper nutrition, health care and medicine that is available in developed countries, large numbers of people are falling victim to AIDS. Nutrition (also called nourishment or aliment) is the provision to cells and Organisms of the materials necessary (in the form of food to support They will not only be unable to work, but will also require significant medical care. The forecast is that this will likely cause a collapse of economies and societies in countries with a significant AIDS populationi. In some heavily infected areas, the epidemic has left behind many orphans cared for by elderly grandparents. An orphan (from the Greek ὀρφανός) is a child whose natural parents are absent or dead and who are not there to bring him up ^[138]

The increased mortality in this region will result in a smaller skilled population and labor force. Population decline is the reduction over time in a region's Census. In Economics the people in the labor force are the suppliers of labor This smaller labor force will be predominantly young people, with reduced knowledge and work experience leading to reduced productivity. In Economics the people in the labor force are the suppliers of labor Work experience is the Experience that a person has working or working in a specific field or occupation An increase in workers’ time off to look after sick family members or for sick leave will also lower productivity. Sick leave (or sickness pay or sick pay) is an employee benefit in the form of paid leave which can be taken during periods of sickness to attend doctor visits or Increased mortality will also weaken the mechanisms that generate human capital and investment in people, through loss of income and the death of parents. Investment or investing is a term with several closely-related meanings in Business management, Finance and Economics, related to saving Income, refers to consumption opportunity gained by an entity within a specified time frame which is generally expressed in monetary terms By killing off mainly young adults, AIDS seriously weakens the taxable population, reducing the resources available for public expenditures such as education and health services not related to AIDS resulting in increasing pressure for the state's finances and slower growth of the economy. Public finance is a field of economics concerned with paying for collective or governmental activities and with the administration and design of those activities This results in a slower growth of the tax base, an effect that will be reinforced if there are growing expenditures on treating the sick, training (to replace sick workers), sick pay and caring for AIDS orphans. This is especially true if the sharp increase in adult mortality shifts the responsibility and blame from the family to the government in caring for these orphans. ^[138]

On the level of the household, AIDS results in both the loss of income and increased spending on healthcare by the household. The income effects of this lead to spending reduction as well as a substitution effect away from education and towards healthcare and funeral spending. A study in Côte d'Ivoire showed that households with an HIV/AIDS patient spent twice as much on medical expenses as other households. Côte d'Ivoire (ˌkoʊt divˈwɑː(r ' in English, kot diˈvwaʀ in French) or Ivory Coast, officially the Republic of Côte d'Ivoire, is a ^[139]

AIDS denialism

Main article: AIDS denialism

A small group of activists, including several scientists who do not study HIV/AIDS, question the connection between HIV and AIDS,^[140] the existence of HIV itself,^[141] or the validity of current testing and treatment methods. AIDS denialism refers to the views of a loosely connected group of individuals and organizations who deny that the Human immunodeficiency virus (HIV is the cause of acquired Though these claims have been examined and thoroughly rejected by the scientific community,^[142] they continue to be promulgated through the Internet^[143] and have had a significant political impact, particularly in South Africa, where President Thabo Mbeki's embrace of AIDS denialism has been blamed for an ineffective response to that country's AIDS epidemic. The scientific community consists of the total body of Scientists its relationships and interactions The Internet is a global system of interconnected Computer networks The Republic of South Africa (also known by other official names) is a country located at the southern tip of the continent of Africa Thabo Mvuyelwa Mbeki (born 18 June 1942 is a South African politician who served as President of South Africa from 1999 to 24 September 2008 ^{[144][145][146]}

Notes and references

Further reading

• 2007 AIDS epidemic update (pdf). UNAIDS. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• UNAIDS Annual Report - Making the money work (pdf). UNAIDS. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• Financial Resources Required to Achieve, Universal Access to HIV Prevention, Treatment Care and Support (pdf). UNAIDS. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• Practical Guidelines for Intensifying HIV Prevention (pdf). UNAIDS. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• Antiretroviral Formulations (pdf). US Department of Health and Human Services. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• Approved Medications to Treat HIV Infection (pdf). US Department of Health and Human Services. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• The HIV Life Cycle (pdf). US Department of Health and Human Services. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.

External links

• HIV/AIDS at the Open Directory Project
• AIDSinfo - HIV/AIDS Treatment Information. The Open Directory Project ( ODP) also known as dmoz (from directory US Department of Health and Human Services. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• UNAIDS: The Joint United Nations Programme on HIV/AIDS. UNAIDS. Retrieved on 2008-03-21. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 630 - Byzantine emperor Heraclius restores the True Cross to Jerusalem.
• AIDS.gov: Portal to all Federal HIV/AIDS information. Office of HIV/AIDS Policy. Retrieved on 2008-05-20. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 325 - The First Council of Nicaea &ndash the first Ecumenical Council of the Christian Church is held