[Study on the frequency of primary rubella infection among early pregnant women]

Rubella virus is the common agent of prenatal infection. Congenital malformation rate is very high among pregnant women who are infected rubella primarily during the first trimester of pregnancy. Sera were taken from 10412 early pregnant women in 4 cities and 4 countries of 6 Provinces in 4 districts of China from April 1990 to October 1991 for detection of special IgM antibodies against rubella with Capture-EIA test. The results showed that the primary infection rate was 0.318% of those women without clinical symptoms of rubella during their early pregnant period. A high infection rate of 1.477% was found in those women with clinical symptoms, 4.7 times the former rate. The total infection rate of 10,412 women was 0.461%. By this rate at least some 40 thousand CRS infants will be born each year in China. This figure is more than the sum of patients suffering from poliomyelitis and Japanese encephalitis, and much more than the number disabled from these two infectious diseases. Some suggestions to prevent CRS were put forward in this paper.