Rubella outbreak in Thailand 1983-1984: a study at Siriraj Hospital.

The recent rubella epidemic in Thailand prevailed from September 1983 to August 1984 with its peak in March. Throughout the outbreak, approximately 70% of the cases diagnosed clinical rubella were laboratory proved. In the middle of the outbreak, accuracy of the clinical diagnosis was 75-87%, while it was 25-33% at the beginning and the end. Concerning the clinical findings in rubella, maculopapular rash may be generalized or localized, and lymphadenopathy occurred only in 40% of the clinical cases. Lymphadenopathy and respiratory symptoms appeared 3 times more frequent than those in the non-rubella cases. Rubella inapparent infection occurred in 5.14% of the contact cases. Acquisition of the disease after contact did not depend on the degree of close relationship between the index cases and the contact cases. Outcome of pregnancy and congenital rubella infection after the outbreak have to be further investigated.