Investigation of transplacental transmission of TT virus in mother - newborn pairs

TT virus (TTV) is widespread throughout the world and can be detected in 50-95% of healthy individuals. However, in chronic hepatitis C virus (HCV) infected patients coinfected with TTV, histological activity indices were higher than patients with HCV infection alone. There are studies which indicate that TTV can cause aplastic anemia and thrombocytopenia. While TTV is known to be transmitted through blood transfusions and by fecal-oral route, published information on transplasental transmission is controversial. The aims of this study were to detect the frequency of TTV infection among healthy pregnant women and to search whether TTV is transmitted transplasentally during pregnancy. For this purpose, plasma samples collected from 54 women and their newborns were investigated by polymerase chain reaction (PCR), and viral loads were determined for infected newborns, and their respective mothers. Also, ten mothers whose newborns were tested negative for TTV-DNA were enrolled in viral load tests for comparison. TTV-DNA was detected in 49 (90.7%) of 54 women. Of 49 newborns whose mothers were infected with TTV, only 4 (8.2%) were found positive for TTV-DNA. There was no statistically significant difference in TTV-DNA loads between mothers who transmitted the virus and those who did not (Mann-Whitney U analysis Z=-0.071, P=0.944). As a result, transplasental transmission of TTV is possible but occurs in low frequency and independent of viral load.