Transplacental transmission of influenza A (H1N1) virus--is it really possible?

We previously shared our H1N1 pandemic influenza experiences in two separate reports that were about transplacental transmission and the measures that should be taken in neonatal intensive care units (NICUs) during the pandemics. From November 9 through December 25, 82 pregnant women were admitted to our hospital with suspected or proven H1N1 infection, among whom 27 had laboratory-confirmed infection. During the pandemics, 24 infants were admitted to our NICU, of whom 22 were born to a mother who had proven H1N1 infection with polymerase chain reaction (PCR). The infection control procedures developed for novel H1N1 infection were applied. Nasal swab samples were collected immediately after birth and sent for analysis in order to screen for H1N1 2009 infection, but all samples were PCRnegative. Furthermore, placentas of seven infected women were examined both microscopically and with PCR. Microscopic examination revealed some nonspecific changes similar to the case of Çetinkaya et al., which could not be attributed to the H1N1 infection itself. PCR results of placentas were all negative and did not indicate any viral replication2,3.-