Isolation of poxvirus vacciniae from embryonal tissues of women vaccinated against smallpox during early pregnancy (Serbocroatian)

Abstract

During a smallpox epidemic in Yugoslavia in 1972, a number of pregnant women were vaccinated against smallpox. A virological study was undertaken, by attempting the isolation of vaccinia virus from embryonal tissues obtained by curettage. Embryonal tissues from 150 women vaccinated during early pregnancy were pooled in 15 pools. As controls, 50 specimens of embryonal tissues were obtained from nonvaccinated pregnant women and they were pooled in 5 pools. Inoculation of the embryonal tissue pools on chorioallantoic membranes (CAM) of chicken embryos detected the presence of vaccinia virus in one pool out of 15 pools consisting of the embryonal tissues obtained from vaccinated pregnant women. The vaccinia virus was identified by the appearance of infected CAMs, by electron microscopy, and by the neurtralization test. In 3 pools (2 from the vaccinated group and 1 from the nonvaccinated control group) herpesviruses were isolated in CAM. The finding of poxvirus vacciniae in one pool of embryonal tissues indicated the infection of an embryo during early pregnancy. The frequency of such an event is considered to be lower than 1%, and the outcome of pregnancy could not be predicted.