A 5-year comparison of performance of sentinel and mandatory notification surveillance systems for measles in Switzerland.
A sensitive, specific and timely surveillance is necessary to monitor progress towards measles elimination. We evaluated the performance of sentinel and mandatory-based surveillance systems for measles in Switzerland during a 5-year period by comparing 145 sentinel and 740 mandatory notified cases. The higher proportion of physicians who reported at least one case per year in the sentinel system suggests underreporting in the recently introduced mandatory surveillance for measles. Accordingly, the latter reported 2-36-fold lower estimates for incidence rates than the sentinel surveillance. However, these estimates were only 0.6-12-fold lower when we considered confirmed cases alone, which indicates a higher specificity of the mandatory surveillance system. In contrast, the sentinel network, which covers 3.5% of all outpatient consultations, detected only weakly and late a major national measles epidemic in 2003 and completely missed 2 of 10 cantonal outbreaks. Despite its better timeliness and greater sensitivity in case detection, the sentinel system, in the current situation of low incidence, is insufficient to perform measles control and to monitor progress towards elimination.
Richard
Jean-Luc
JL
Division of Communicable Diseases, Federal Office of Public Health, Schwarztorstrasse 96, Bern, Switzerland. jean-luc.richard@bag.admin.ch
Vidondo
Beatriz
B
Mäusezahl
Mirjam
M
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D018563:Disease Notification / Q000379:methods / Q000592:standards* / Q000706:statistics & numerical data*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D015994:Incidence; D007753:Laboratories / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D008457:Measles / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control; D008458:Measles Vaccine; D010820:Physicians / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D018571:Sentinel Surveillance; D013557:Switzerland / Q000453:epidemiology
D008458:Measles Vaccine