Cheap vaccine needed for Africa's meningitis epidemic

With an epidemic of a rare strain of meningitis threatening to infect up to 4 million Africans by January, the World Health Organization (WHO) has made an urgent plea for an affordable vaccine.

Before 2002, nearly all cases of meningitis in Africa were caused by Neisseria meningitidis type A. In January, cases involving infection by serotype W135 began accumulating, and continued through the end of the meningitis season in May. More than 12 000 people were infected by W135, and 8.5% of them died.

N. meningitidis W135 has caused sporadic cases for nearly 60 years, but it never received much attention until outbreaks in Europe in 2000 were associated with the hajj to Mecca. In 2001, many countries began vaccinating travellers to the Middle East with a tetravalent vaccine effective against strains A, C, Y and W135. However, the cost of US$5 per dose is prohibitive for poor African countries like Burkina Faso.

At a recent WHO meeting in Burkina Faso, participants suggested the vaccines should not cost more than US$1. WHO, UNICEF, Médecins Sans Frontières and the Red Cross are negotiating with manufacturers for a lower vaccine price. Development of a monovalent vaccine against the W135 strain is expected to take up to 18 months, which would be far too late for the upcoming meningitis season.

The largest outbreaks of meningococcal meningitis, the only form of bacterial meningitis to cause epidemics, are in sub-Saharan Africa within the “meningitis belt” that extends from Ethiopia to Senegal. Burkina Faso alone reported 42 000 cases in 1997. — James Maskalyk, CMAJ