Measles Epidemic in Romania, 1996–1998; Assessment of Vaccine Effectiveness by Case-Control and Cohort Studies

• Published in: American journal of epidemiology Vol. 150; no. 11; pp. 1250 - 1257
• Main Authors: Hennessey, Karen A., lon-Nedelcu, Nicolae, Craciun, Maria-Dorina, Toma, Flores, Wattigney, Wendy, Strebel, Peter M.
• Format: Journal Article
• Language: English
• Published: Cary, NC Oxford University Press 01.12.1999
• Subjects: Adolescent; Adult; Age Factors; Biological and medical sciences; Case-Control Studies; Child; Child, Preschool; Cohort Studies; Disease Outbreaks; Epidemiology. Vaccinations; General aspects; Humans; immunity; immunization programs; Immunization Schedule; Infant; Infant, Newborn; Infectious diseases; measles; Measles - epidemiology; Measles - prevention & control; Measles - transmission; measles vaccine; Measles Vaccine - immunology; Measles Vaccine - standards; Measles virus; Medical sciences; Models, Theoretical; Population; Retrospective Studies; Romania; Romania - epidemiology; Vaccination; Europe; Romania; Human; Evaluation; Sanitary program; Immunization; Vaccination; Duration; Case control study; Epidemiology; Immunity; Infection; Prevention; Efficiency; Viral disease; Cohort study; Measles; Public health; Health Services; Age Factors; Eastern Europe; Viral Diseases; Biology; Vaccines; Delivery Of Health Care; Research Methodology; Case Control Studies; Population Characteristics; Population; Research Report; Child; Demographic Factors; Romania; Measles > prevention and control; Health; Europe; Risk Factors; Youth; Communicable Disease Control; Diseases; Studies; Developed Countries; Primary Health Care
• ISSN: 0002-9262; 1476-6256
• DOI: 10.1093/oxfordjournals.aje.a009952

A measles epidemic occurred in Romania with 32, 915 cases and 21 deaths reported between November 1996 and June 1998, despite high vaccination coverage since the early 1980s. Most cases were unvaccinated children aged<2 years and vaccinated school children. A case-control study among preschool children and a cohort study among primary-school children were conducted to eslimate effectiveness of Romanian produced measles vaccine, and to evaluate age at vaccination and waning immunity as risk factors for vaccine failure. Both studies indicated that measles vaccine was highly effective. One dose reduced the risk for measles by 89% (95% onfidence interval (CI) 85, 91); two doses reduced the risk by 96% (95%CI 92, 98). Children vaccinated at <1 year of age were not at increased risk for measles compared with children vaccinated at ↑1 year. Warning immunity was not identified as a risk factor since vaccint effectiveness was similar for children vaccinated 6–8, 9–11, and 12–14 years in the past. Because specific groups were not at risk for vaccine failure, an immunization campaign that targets all school-aged children who lack two doses may be an effective strategy for preventing outbreaks. A mass campatign followed by increased first-dose coverage should provide the population immunity required to interrupt indigenous measles virus transmission in Romania. Am J Epidemiol 1999; 150; 1250–7.