Doraisingham S, Goh K T, Ling A E, Yu M
Bull World Health Organ. 1988;66(1):57-63.
Prospective laboratory surveillance of influenza viruses has been carried out since 1973 in Singapore. The results indicate that antigenic shift variants caused epidemics at various times of the year over this period, whereas drift variants were associated with a regular increase in incidence during the second and fourth calendar quarters. Outbreaks due to influenza A virus occurred every year and to influenza B virus at intervals of 16-24 months. Between outbreaks, viruses belonging to either of the two types could be detected during most months, and certain variants appeared several months before the outbreaks they subsequently caused. The factors that contribute to the seasonal pattern are at present unknown.
自1973年以来,新加坡一直在对流感病毒进行前瞻性实验室监测。结果表明,在此期间,抗原转变变异株在一年中的不同时间引发了疫情,而抗原漂移变异株与第二和第四日历季度发病率的定期上升有关。甲型流感病毒每年都会引发疫情,乙型流感病毒每隔16 - 24个月爆发一次。在两次疫情爆发之间,大多数月份都能检测到这两种类型中的任何一种病毒,并且某些变异株在它们随后引发的疫情爆发前几个月就已出现。目前尚不清楚导致季节性模式的因素。