Table 4. Population residing in districts at risk for meningitis epidemics in Africa.

Risk	No. of districts	1990 population in millions (%)
Low	1,572	291 (49)
Moderate	971	162 (27)
High	482	102 (17)
Very high	251	44 (7)
Not known	5	1 (<1)
Total	3,281	600