CONTROL OF RUBELLA AND CONGENITAL-RUBELLA SYNDROME (CRS) IN DEVELOPING-COUNTRIES .1. BURDEN OF DISEASE FROM CRS

Congenital rubella syndrome (CRS) can lead to deafness, heart disease, and cataracts, and a variety of other permanent manifestations. In de veloping countries, the burden of CRS has been assessed as follows: by surveillance of CRS; by surveillance of acquired rubella; by age-stra tified serosurveys; and by serosurveys documenting the rubella suscept ibility of women of childbearing age. During rubella outbreaks, rates of CRS per 1000 live births were at least 1.7 in Israel, 1.7 in Jamaic a, 0.7 in Oman, 2.2 in Panama, 1.5 in Singapore, 0.9 in Sri Lanka, and 0.6 in Trinidad and Tobago. These rates are similar to those reported from industrialized countries during the pre-vaccine era. Special stu dies of CRS have been reported from all WHO regions. Rubella surveilla nce data show that epidemics occur every 4-7 years, similar to the sit uation in Europe during the pre-vaccination era. In developing countri es, the estimated average age at infection varies from 2-3 years to 8 years. For 45 developing countries we identified serosurveys of women of childbearing age that had enrolled greater than or equal to 100 ind ividuals. The proportion of women who remained susceptible to rubella (e.g. seronegative) was < 10% in 13 countries, 10-24% in 20 countries, and greater than or equal to 25% in 12 countries. Discussed are metho ds to improve the surveillance of rubella and CRS in developing countr ies.