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A major human pathogen belonging to the bacterial genus Neisseria, and the cause of meningococcal meningitis and meningococcemia. The official designation is N. meningitidis. The meningococcus is a gram-negative, aerobic, nonmotile diplococcus. It is fastidious in its growth requirements and is very susceptible to adverse physical and chemical conditions.

Humans are the only known natural host of the meningococcus. Transmission occurs by droplets directly from person to person. Fomites and aerosols are probably unimportant in the spread of the organism. The most frequent form of host-parasite relationship is asymptomatic carriage in the nasopharynx.

The most common clinical syndrome caused by the meningococcus is meningitis, which is characterized by fever, headache, nausea, vomiting, and neck stiffness and has a fatality rate of 15% (higher in infants and adults over 60). Disturbance of the state of consciousness quickly occurs, leading to stupor and coma. Many cases also have a typical skin rash consisting of petechiae or purpura. See Meningitis


Common name for Neisseria meningitidis.
References in periodicals archive ?
The second case involves a suspected not yet confirmed invasive meningococcus infection in a child from the Horehronie (Upper Hron) region of central Slovakia, aged five, who suddenly got sick on January 4.
The post mortem, which was completed late on Saturday, showed that the child died "of an infection that destroyed the adrenal glands, possibly meningococcus.
The university system announced that, starting in 2017, it will require all students to receive vaccination against measles, mumps, rubella, chickenpox, meningococcus, tetanus and whooping cough.
In the past few years, well-publicized outbreaks of meningococcus B have occurred on some university campuses.
ABIVAX has signed an agreement with The Finlay Institute, Havana, Cuba, that will allow it to commercialize vaccines against typhoid, meningococcus, and leptospirosis, in Asian and Latin American markets.
Most recently, he was director of the Vaccine Development Global Program at PATH, where he built and advanced the development of vaccines against pneumococcus, rotavirus, ETEC, shigella, meningococcus, influenza, respiratory syncytial virus, polio and Japanese encephalitis.
Vaccines are available in the United States for warding off four types of the meningococcus.
influenzae type b 10 cases, streptococcus pneumoniae 15 cases and meningococcus only one case respectively.
It induces a higher and more sustainable immune response against group A meningococcus, it is expected to confer long-term protection not only for those who receive the vaccine, but to family members and others who would otherwise have been exposed to meningitis and it is expected to be particularly effective in protecting children under two years of age, who do not respond to conventional polysaccharide vaccines.
Teenagers, people from manual work social classes and those who have recently had colds are also at higher risk of carrying the meningococcus bug in their throats and noses, according to the research carried out at a Powys school.
VA-MENGOC-BC is the only vaccine available in the world against the disease caused by meningococcus B and has been included since 1991 in Cuba's national infant immunization program.