Abstract

This study was designated to determine whether a program of screening for rubella antibodies during pregnancy, coupled with selective vaccination after delivery, could effectively increase herd immunity. One thousand women were studied when they returned for further antenatal care after having been screened, and possibly vaccinated, during an earlier pregnancy. Overall, the program was shown to be 83% effective since 108 women were truly seronegative in their initial pregnancies and 90 of them had been rendered immune by the time of their next pregnancy. The 18 failures of the program were attributed to the haemagglutination inhibition test employed (eight cases), failure to administer vaccine (seven cases) and true vaccine failures (three cases). Five pregnant women became infected with rubella virus during the study but all were in their initial pregnancies. All seronegative women were shown to follow the instruction not to become pregnant within three months of vaccination. We conclude that a program of screening for immunity, together with selective vaccination post partum, can significantly reduce both the number of susceptible women and the number who experience rubella infection during pregnancy. Such programs should be vigorously encouraged as a means of helping to prevent congenital rubella.