title: Measles outbreak in Bulgaria.
mesh_terms: D000293:Adolescent; D000328:Adult; D002031:Bulgaria / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks / Q000517:prevention & control*; D006801:Humans; D007223:Infant; D008457:Measles / Q000453:epidemiology* / Q000517:prevention & control; D012307:Risk Factors