Effects of the yellow fever vaccination in pregnant mice

Author(s)

Fernanda Carini da Silva

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2010-04-30

Examining board members

Estela Maris Andrade Forell Bevilacqua; Fábio Siviero; Lily Yin Weckx

• Advisor: Estela Maris Andrade Forell Bevilacqua

Abstract

The risk of placental transmission to the fetus, associated with susceptibility to neuroinvasion of the 17D virus led to the recommendation that the vaccine against yellow fever (YF) was not administered during pregnancy. Intended to evaluate the effect of the vaccine in gestational performance of pregnant mice. The results showed a decrease in fetal viability caused by vaccination. Antigen reactivity of YF was observed in maternal and live fetuses liver tissue. In the placenta, the viral antigen was not observed in maternal-fetal barrier. In the stillborn fetuses and resorption, this passage seemed more pronounced; reactivity was observed in several organs. The viral antigen was detected in all placental regions. The detection of viral RNA in the samples indicates that there is viral activity in fetal tissues. Our findings indicate that there are stages of pregnancy more susceptible to viral vaccine infection that could determine fetal loss. The presence of the antigen and viral activity in fetal liver suggests that the vaccine virus is transmitted from mother to fetus. (AU)