Schoub B D, Johnson S, McAnerney J, Blackburn N K
Department of Health, University of the Witwatersrand.
S Afr Med J. 1994 Oct;84(10):674-8.
To establish an ongoing active surveillance programme for acute respiratory infections in general, and influenza in particular.
A network of 16 sentinel primary health care providers furnished morbidity information and clinical specimens for virus characterisation supplemented by school absenteeism and regional mortality data.
General practices, hospital outpatient departments and staff clinics in the Witwatersrand area.
Subjects treated for acute respiratory infections by 7 general practitioners, 1 specialist pulmonologist, 4 paediatric outpatient departments, 1 mine hospital and university, factory and institutional staff clinics. Absenteeism data were obtained from 8 primary and 6 high schools in the region (representing 9,000 pupils).
Morbidity information and strain characterisation of influenza isolates as well as other viral respiratory pathogens, school absenteeism, seasonal excess mortality.
The most sensitive indicator of influenza activity was virus isolation, which gives an earlier warning signal of an impending epidemic than morbidity or absenteeism parameters. Both morbidity and school absenteeism provided quantitative indicators of the severity of the epidemic. Mortality from all causes showed characteristic winter increases in the 65-year-old and older population which were not seen in younger individuals. Circulating influenza viral strains matched the strains recommended for the vaccine in 1991 and 1992, but not in 1993.
The course and extent of the annual winter influenza epidemic can be charted by means of an active surveillance programme, with sentinel primary health care providers furnishing morbidity data and clinical material from which virus isolations can be made. Antigenic characterisation of the isolates demonstrated that circulating strains may not match recommended strains in northern hemisphere-formulated vaccines and stresses the need for a southern hemisphere vaccine formulation for South Africa. Absenteeism information provides an indicator of the impact of influenza on the economy and excess mortality data emphasise the need for routine immunisation of the elderly.
建立一个针对一般急性呼吸道感染，特别是流感的持续主动监测项目。
由16个哨点基层医疗服务提供者组成的网络提供发病信息和临床标本以进行病毒特征鉴定，并辅以学校缺勤率和区域死亡率数据。
威特沃特斯兰德地区的全科诊所、医院门诊部和员工诊所。
由7名全科医生、1名专科肺科医生、4个儿科门诊部、1家矿山医院以及大学、工厂和机构员工诊所治疗的急性呼吸道感染患者。缺勤率数据来自该地区的8所小学和6所高中（代表9000名学生）。
流感毒株以及其他病毒性呼吸道病原体的发病信息和毒株特征鉴定、学校缺勤率、季节性超额死亡率。
流感活动最敏感的指标是病毒分离，它比发病率或缺勤率参数能更早发出即将流行的预警信号。发病率和学校缺勤率都提供了该流行病严重程度的定量指标。所有原因导致的死亡率在65岁及以上人群中呈现出典型的冬季上升，而在年轻人中则未观察到。1991年和1992年流行的流感病毒株与推荐用于疫苗的毒株匹配，但1993年不匹配。
通过主动监测项目可以描绘出每年冬季流感流行的过程和范围，哨点基层医疗服务提供者提供发病数据和可用于病毒分离的临床材料。分离株的抗原特征表明，流行毒株可能与北半球配方疫苗中推荐的毒株不匹配，并强调南非需要南半球配方疫苗。缺勤率信息提供了流感对经济影响的指标，超额死亡率数据强调了对老年人进行常规免疫的必要性。
