Etiology of a suspected measles outbreak: preceding measles reduction activities in Pakistan.

OBJECTIVE: To characterize patients with suspected measles, determine the magnitude of the outbreak in selected areas, and perform laboratory testing on patients with suspected measles to confirm the etiology of the outbreak. STUDY DESIGN: Cross-sectional survey. PLACE AND DURATION OF STUDY: Islamabad and Rawalpindi in June 2006. METHODOLOGY: Survey and specimen collection from households was carried out in areas affected by rash and fever during the outbreak. Teams asked if household members had rash and fever and administered a detailed questionnaire of clinical signs and symptoms for measles for each person who reported a rash and fever episode. A sample of cases with fever, rash, and either cough, conjunctivitis, or coryza was laboratory tested for measles and rubella. RESULTS: Of 2,225 households visited, 284 individuals met the rash and fever case definition. Laboratory testing of eleven blood specimens revealed that the rash and fever outbreak was caused by rubella in 6 and measles in 2 with three equivocal results. CONCLUSION: Laboratory confirmation of suspected measles cases is essential during measles elimination activities in Pakistan and other countries with endemic rubella.