Seroepidemiology of measles in Addis Ababa, Ethiopia: implications for control through vaccination.
We undertook a representative survey of measles antibodies in Addis Ababa, Ethiopia 1994, to characterize immunity and transmission. Specific-antibody levels (IU/l) were determined by ELISA for 4654 sera from individuals aged 0-49 years (1805 < 15 years) collected by stratified household-cluster sampling. The proportion seronegative (< 100 IU/l) was 20% (95% CI: 16-25) in children 9-59 months old, declining to 9% (7-12) in 5-9 year olds, 5% (4-7) in 10-14 year olds, and < 1% in adults. The proportion of children (< 15 years old) with low-level antibody (100-255 IU/l) was 8% (7-10). Vaccination and an absence of a history of measles illness were strongly associated with low-level antibody. History of measles vaccination in 9 months to 14-year-old children was approximately 80%. We estimate a primary vaccine failure rate of 21% (12-34) and continued high measles incidence of 22 per 100 susceptibles (19-24) per annum. Our data support the introduction of campaign vaccination in the city in 1998, although higher routine vaccine coverage is required to sustain the impact. The implications of a high prevalence of low-level antibody are discussed.
Enquselassie
F
F
Department of Community Health, Faculty of Medicine, University of Addis Ababa, PO Box 1176, Addis Ababa, Ethiopia.
Ayele
W
W
Dejene
A
A
Messele
T
T
Abebe
A
A
Cutts
F T
FT
Nokes
D J
DJ
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000704:Analysis of Variance; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005002:Ethiopia / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D016015:Logistic Models; D008457:Measles / Q000453:epidemiology* / Q000517:prevention & control* / Q000635:transmission; D008458:Measles Vaccine / Q000276:immunology*; D008875:Middle Aged; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D017211:Treatment Failure; D014505:Urban Population; D014611:Vaccination / Q000706:statistics & numerical data*
D008458:Measles Vaccine