Zika virus, transmitted by Aedes mosquitoes, can reach the placenta of pregnant women, jeopardizing the fetus’s, reported a study by the Carlos Chagas Institute in Paraná Brazil. According with their results, Zika DNA was found in the placenta of a pregnant woman who had a “missed abortion“, which occurs when a fetus dies, but the body does not recognize the pregnancy loss.
As reported by the Carlos Chagas Institute, the pregnant woman reported having symptoms compatible to infection caused by Zika virus in the sixth week of pregnancy, two weeks before she had the abortion. Among those symptoms, she had reported having spots on the body, which raised suspicions among the researchers.
In the research, led by virologist Claudia Nunez Duarte dos Santos, antibodies were used to first identify that it was an infection similar to that caused by Zika; and then, the team found the virus using molecular genetic tests, detecting traces of the virus in the pregnant woman and the embryo.
“We identified the viral genome, through techniques of RT-PCR (reverse transcription followed by polymerase chain reaction) in real time, and tests to rule out dengue infection, which were negative,” said Nunes.
The study, which had the support of the Pontifical Catholic University of Paraná (PUC-PR), found that the virus can reach the fetus through a specific cell called ‘Hofbauer‘, which is part of the immune system and acts as a protective barrier of the placenta in pregnant women.
The researchers’ hypothesis is that, since Hofbauer cells have migratory capacity, they may “carry” the virus into placenta, causing fetal infection similarly to mother-to-child transmission of HIV.
According with the Carlos Chagas Institute, this research can help find evidence of whether Zika virus is the cause of microcephaly recorded in various pregnancies of Brazilian women who were infected by the virus.
“Although we cannot relate this result with cases of microcephaly and congenital abnormalities, it confirms unequivocally the intrauterine transmission of Zika virus,” Nunes said.
Furthermore, she added that this result may also help when planning antiviral strategies to “block infection and/or transmission processes.”
Since the 1950s, the virus has been known to occur within a narrow equatorial belt from Africa to Asia. However, in 2014 the virus spread across the Pacific Ocean, appearing in the American continent for the first time in March 2014. It is a vector disease transmitted by Aedes mosquitoes, similarly to dengue and chikungunya. The virus causes a disease called Zika fever or Zika disease.
While Zika fever is generally considered a mild condition, the results of this research suggest that the spread of the disease carries a much bigger risk than previously assumed. Therefore, taking preventive measures is fundamental in places where the virus is endemic, not only to protect ourselves, but also to reduce the risk of contagion among pregnant women.
Among the recommendations for preventing mosquito bites are: wearing long sleeves, long trousers and mosquito repellent; sleeping with air conditioning; using mosquito nets; avoid standing water that serve as mosquito breeding: tires, buckets, puddles and containers; and maintaining water tanks in clean conditions and properly closed.