Sero-epidemiology of rubella in the urban population of Addis Ababa, Ethiopia

• Published in: Epidemiology and infection Vol. 124; no. 3; pp. 467 - 479
• Main Authors: CUTTS, F. T., ABEBE, A., MESSELE, T., DEJENE, A., ENQUSELASSIE, F., NIGATU, W., NOKES, D. J.
• Format: Journal Article
• Language: English
• Published: Cambridge Cambridge University Press 01.06.2000
• Subjects: Adolescent; Adult; Age Factors; Age groups; Age structure; Antibodies; Antibody Formation; Biological and medical sciences; Child; Child, Preschool; Congenital rubella syndrome; Epidemiology; Ethiopia - epidemiology; Ethiopia, Addis Ababa; Female; Fundamental and applied biological sciences. Psychology; Health Surveys; Human viral diseases; Humans; Immunity; Incidence; Infant; Infant, Newborn; Infections; Infectious diseases; Male; Measles; Medical sciences; Microbiology; Middle Aged; Prevalence; Rubella; Rubella - epidemiology; Rubella - immunology; Rubella Syndrome, Congenital - epidemiology; Rubella Syndrome, Congenital - immunology; Rubella Vaccine - administration & dosage; Rubella virus; Seroepidemiologic studies; Vaccination; Viral diseases; Viral diseases with cutaneous or mucosal lesions and viral diseases of the eye; Virology; Ethiopia; Africa; Human; Rubella; Urban environment; Prevalence; Rubivirus; Togaviridae; Serology; Rubella virus; Epidemiology; Infection; Virus; Viral disease; Age
• ISSN: 0950-2688; 1469-4409
• DOI: 10.1017/S0950268899003532

We conducted a community-based cluster sample survey of rubella sero-epidemiology in Addis Ababa, Ethiopia in 1994. Among 4666 individuals for whom complete data were available, rubella antibody prevalence was 91% (95% confidence interval: 90, 92). On multivariable analysis, seroprevalence was lower among individuals who were resident in Addis Ababa for 1 year or less. Approx. 50% seroprevalence was attained by age 4 years, and the estimated average age at infection was 5·2 years. The highest age-specific force of infection was estimated to occur in 5- to 9-year-olds. The early age at infection corresponded with a low estimated incidence of congenital rubella syndrome (CRS) of 0·3 per 1000 live births, equivalent to nine cases of CRS in 1994. The predicted critical level of immunity for elimination of rubella via vaccination was 85–91%, requiring 89–96% coverage with a vaccine of 95% effectiveness. Unless very high coverage of rubella vaccine could be guaranteed, the introduction of childhood vaccination could increase the incidence of CRS in Addis Ababa.