Zika virus can cross placenta, confirms Brazilian institute

Researchers, from the Carlos Chagas Institute of Paraná Fiocruz, confirmed that the Zika virus can cross the placenta during pregnancy. The infection of pregnant women is suspected to have cause a rise in microcephaly cases recorded in the country.

The analysis was conducted with samples of a patient, from the Northeast region, who had a missed abortion (when the fetus is no longer developing normally) in the eighth week of pregnancy, after presenting Zika virus infection symptoms.

According to the institute, placenta samples underwent lab testing carried out in similar virus infection, like dengue, chikungunya and yellow fever. The results were positive and they have found viral proteins in placental cells.

After that, placental tissue samples were removed and were given analysis using molecular techniques. The exam confirmed the placental cells were infected by Zika and confirmed the placental transmission of the virus.

Fiocruz scientists believe that the virus may be using the migratory capacity of these cells to reach fetal vessels.

Cláudia Nunes dos Santos, chief of the Institute's Molecular Virology Laboratory, reported that although it is not possible yet to link the findings to microcephaly cases and other congenital abnormalities, the result unequivocally confirms the intrauterine transmission of the Zika virus, she declared. The result also helps "acquire knowledge of  their biology and interaction with host cells and help develop antiviral strategies to prevent the infection and/or transmission processes," she explained.

Translated by Amarílis Anchieta