Meningococcal disease

Nearly a year ago, the History of Vaccines blog covered the introduction of MenAfriVac (PsA-TT) to the African meningitis belt, an area stretching from Senegal to Ethiopia, where epidemic waves of meningitis occur and can last up to three years. In the largest of these epidemic waves in history, meningitis killed more than 25,000 people from 1996 to 1997. MenAfriVac, a vaccine against the Group A type of meningococci bacteria that causes 80 to 85% of meningitis cases in the African epidemics, was the result of a collaboration between the World Health Organization (WHO) and PATH. The first vaccine developed specifically for use in Africa, it was introduced last year in Burkina Faso, Mali, and Niger, with almost 20 million people aged 1 to 29 (the age range most at risk) being vaccinated.

In June, the History of Vaccines blog reported that all three countries were reporting record lows in confirmed Group A meningitis cases during an epidemic season. Now the vaccine is being introduced to three more African countries: Cameroon, Chad, and Nigeria. More

Last December, the History of Vaccines blog covered the introduction of MenAfriVac to the African meningitis belt, an area stretching from Senegal to Ethiopia, where epidemic waves of meningitis occur and can last up to three years. In the largest of these epidemic waves in history, meningitis killed more than 25,000 people from 1996 to 1997.

Polysaccharide vaccines are sometimes used to try to control outbreaks after they have begun: so-called “emergency vaccination” efforts designed to keep meningococcal epidemics from spreading further. However, these types of reactive efforts are very expensive and difficult to manage, and polysaccharide vaccines do not induce long-lasting immunity against meningococcal bacteria. (For more about the different types of vaccines, see our article and Types of Vaccines activity.)

Within these African epidemics, between 80 and 85% of cases are caused by a single group of meningococcal bacteria: group A. In 2000, a group of global health leaders gathered together by the World Health Organization (WHO) determined that a meningitis vaccine could be developed specifically for use in Africa: a low-cost vaccine that would focus solely on the Group A bacteria. The Bill & Melinda Gates Foundation provided a ten-year grant for what would become the Meningitis Vaccine Project (MVP). More

In the United States, meningitis is thought of as an extremely rare disease. It usually appears in the news when a college student has fallen ill, amid reminders by public health officials that a meningococcal vaccine can protect against diseases caused by Neisseria meningitidis bacteria, including meningitis. In 2008 (the most recent year for which data are available) only about 1,100 total cases of meningococcal disease were reported in the United States, and meningitis cases were only a fraction of that number.

In other parts of the world, however, meningitis takes a much larger toll. In Sub-Saharan Africa, an area that spans from Senegal to Ethiopia is called the “meningitis belt” because of the epidemic waves that occur there, some lasting as long as three years. The largest epidemic wave in history led to more than 25,000 meningitis deaths from 1996 to 1997. In 2009 alone, more than 88,000 cases were reported. Now, a new vaccine developed specifically for use in Africa offers hope that future epidemics may be prevented. More