Greenwood B M, Blakebrough I S, Bradley A K, Wali S, Whittle H C
Lancet. 1984 Jun 16;1(8390):1339-42. doi: 10.1016/s0140-6736(84)91830-0.
The incidence of meningococcal disease varies seasonally in both tropical and temperate countries. This association is most apparent in sub- Saharan Africa, where almost all epidemics start in the dry season and abate during the rains . Meningococcal carriage rates do not vary with season either in Africa or in temperate countries, suggesting that seasonal factors have little influence on the frequency of meningococcal transmission. It is suggested that changes in the ratio of clinical to subclinical cases of infection are more important than changes in the frequency of transmission in producing seasonal variations in the incidence of meningococcal disease. Some evidence to support this hypothesis was obtained during an epidemic of group A meningococcal disease in northern Nigeria in 1977-79.
在热带和温带国家，脑膜炎球菌病的发病率都随季节变化。这种关联在撒哈拉以南非洲最为明显，几乎所有疫情都始于旱季，并在雨季时缓解。在非洲和温带国家，脑膜炎球菌携带率均不随季节变化，这表明季节因素对脑膜炎球菌传播频率影响不大。有人认为，在导致脑膜炎球菌病发病率出现季节性变化方面，感染的临床病例与亚临床病例比例的变化比传播频率的变化更为重要。1977年至1979年在尼日利亚北部发生A群脑膜炎球菌病疫情期间，获得了一些支持这一假说的证据。
