High Quality Content by WIKIPEDIA articles! NmVac4-A/C/Y/W-135 is the commercial name of the Meningococcal meningitis polysaccharide serogroups A,C,Y and W-135 vaccine of JN-International Medical Corporation. The product is specially designed and formulated to be used in developing countries for protecting populations during meningitis disease epidemics. Meningococcal meningitis is a bacterial infection caused by the bacterium Neisseria meningitidis, also known as meningococcus. The vaccine is made from bacterial capsular polysaccharides through fermentation of each individual serogroup of Neisseria meningitidis in bioreactors. Then the polysaccharides are purified, formulated and lyophilized using preservatives and stabilizers to make a vaccine product. The vaccine cannot protect other than Neisseria meningitidis serogroups A,C,Y and W-135 or cannot completely protect from these serogroups.