Post‐pandemic influenza A (H1N1) 2009 virus infection in pregnant women in Ceará, Brazil

Abstract

ObjectiveThe aim of this study was to present results of the post-pandemic phase of A(H1N1)pdm09 virus infection in pregnant women in Ceará, Brazil, during the January–June 2012 influenza season.ResultsOne hundred and fifty-four nasopharyngeal swab samples were collected from pregnant women admitted to hospitals with suspected severe acute respiratory infection (SARI). Fifty-three (34·4%) had laboratory-confirmed A(H1N1)pdm09 virus infection with 15 (28·3%) outpatients and 38 (71·7%) hospitalized. Five (9·4%) women were in the first trimester of pregnancy, 20 (37·7%) in the second trimester of pregnancy, and 24 (45·2%) in the third trimester of pregnancy. Three had no information about the time of pregnancy. Six samples from newborns were also analyzed, of which three were nasopharyngeal swab positive for A(H1N1)pdm09. These swabs were collected immediately after birth, with the exception of one that was collected on the day after birth.ConclusionOur findings suggest that transplacental transfer of influenza viruses could occur as a result of severe illness in pregnancy. It is therefore important to encourage women to be vaccinated against influenza in order to avoid pregnancy complications.

Maternal Influenza A Virus Infection Restricts Fetal and Placental Growth and Adversely Affects the Fetal Thymic Transcriptome

“…Based on proteomic analysis of these stem cells, infection also caused dysregulation of many cellular pathways, including those directly associated with cellular differentiation. Influenza A viral RNA and proteins have been found in the placenta and fetus in individual cases [ 39 , 40 , 41 , 42 , 43 , 45 , 46 , 47 , 48 ]; however, documentation of direct infection is uncommon [ 49 ]. Fetal damage also occurs in the absence of direct influenza virus infection of the fetus [ 50 , 51 ].…”