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MeNZB is a vaccine against a specific strain of group B meningococcus, currently being used to control an epidemic of meningococcal disease in New Zealand. A vaccine is a biological preparation which is used to establish or improve immunity to a particular disease Neisseria meningitidis, also simply known as meningococcus, is a heterotrophic Gram-negative diplococcal Bacterium best known for New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island Most people are able to carry the meningococcus bacteria safely with no ill effects. However, meningococcal disease can cause meningitis and septicaemia, resulting in brain damage, failure of various organs, severe skin and soft-tissue damage, and death. Meningitis is Inflammation of the protective membranes covering the Brain and Spinal cord, known collectively as the Meninges.

Immunisation with MeNZB requires three doses, administered approximately six weeks apart (except in newborns, who have them in conjunction with their 6-week, 3-month and 5-month injections). People who have been fully immunised may still carry the meningococcus bacteria and may still contract meningococcal disease.

Each dose is 0. 5 ml and contains:

The vaccine does not contain any whole bacteria (alive or dead). Aluminium hydroxide, Al(OH3 is the most stable form of Aluminium in normal conditions Histidine (abbreviated as His or H) is one of the 20 standard Amino acids present in Proteins In the Nutritional sense in pH is the measure of the acidity or alkalinity of a Solution. In Medicine, saline (also saline solution) is a general term referring to a sterile solution of Sodium chloride (table Salt) in water The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have The "outer membrane vesicles" it contains are a small part of the "skin" of the bacteria that let the immune system recognise and prepare for being infected with the real thing.

MeNZB vaccine does not contain any human, blood, or bovine (cow)products, egg products, neomycin or the preservative thiomersal (mercury). Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells €”such as nutrients and oxygen—and transports Waste products An egg is a round or oval body laid by the female of many animals consisting of an Ovum surrounded by layers of Membranes and an outer casing which acts to nourish Neomycin is an Aminoglycoside Antibiotic that is found in many topical medications such as creams ointments and eyedrops There are no live meningococcal bacteria in the vaccine and it is not possible to catch the disease or become a carrier of the disease from the vaccine.

The immune system will normally not mount an immune response to the outer membrane vesicles if they are presented alone. The presence of the adjuvant forces the immune system to respond to the membrane vesicles by acting to prevent their breakdown and elimination, while causing local tissue damage to provoke the desired immune reaction.

The histidine pH buffer is to ensure the vaccine stays as close as possible to the pH of human body fluids. This is to ensure the immune system does not waste time trying to neutralise the vaccine instead of responding to the outer membrane vesicles.

The saline (sterile salt and water) is also like packaging. It is required so that all of the above can be dissolved into a solution that can be injected. It is the same salinity (saltiness) as normal human body fluid.

The antigen in MeNZB is prepared from B:4:P1. 7b,4 (NZ 98/254 ) N. meningitidis strain, grown in a fermentor. The bacteria are grown in a synthetic culture medium containing sugar, essential amino acids and essential elements such as iron and potassium. The fermentation does not use bovine or porcine products. The cellular outer membranes are extracted with the detergent deoxycholate, which kills the bacteria. Outer membrane vesicles are purified out of the culture medium by ultracentrifugation, stabilised by histidine and then adsorbed to aluminium hydroxide Al(OH)3 as an adjuvant. Purification is achieved by ultrafiltration/diafiltration.

Since its introduction the vaccine has had a dramatic impact on the epidemic. In April 2008 it was unexpectedly announced by the New Zealand Ministry of Health that the MeNZB vaccination programme will be completed by 31 December 2008, and that after this period no further vaccination will be given. Reasons given for this halt of the programme include that the epidemic was already finishing, and that immune protection given by the vaccine is only short-term. Others speculate that the cost of providing the vaccine is too high for the NZ government to justify.

The vaccine, originally developed in Norway and subject to considerable public controversy as recently as October 2007, was never released for widespread use in that country because the Norwegian epidemic was finishing before it was released. Norway ( Norwegian: Norge ( BokmĂĄl) or Noreg ( Nynorsk) officially the Kingdom of Norway, is a Constitutional In Epidemiology, an epidemic (from Greek epi- upon + demos people is a classification of a disease that appears as new cases in a

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