After several months of research, scientists have finally found a direct link between the Zika virus and the birth defects affecting hundreds of infants in Brazil. This time, the researchers took a new approach by infecting mice pups with the Zika virus and studying the results on brain development.
How The Zika Virus Attacks A Fetus
The study, which was published in several journals including Cell, revealed that the Zika virus does more damage when a mother is infected during the early stages of her pregnancy. This is because the Zika virus actually breaks down the placental barrier and goes straight for the fetus' brain (via LA Times).
The scientists found that once a mother is infected during her first trimester, the Zika virus instantly attacks the uterus and the cells that help protect the placenta. If the fetus is not yet fully developed, the Zika virus prevents the growth of placental blood vessels. The limited blood flow results in stunted fetal development.
The Zika Virus' Other Effect On A Fetus
The Zika virus is not satisfied with simply crossing the placental barrier. Once the protection has been breached, the virus then attacks the stem cells that work on the fetus' developing brain. The Zika virus multiplies at a fast pace, killing off the stem cells and neurons in the brain.
The Human Fetus' Brain Vs The Mice Pups' Brains
Human fetuses that are infected with the Zika virus usually end up with microcephaly. Although this was not observed in the brains of the infected mouse pups, the brains still ended up being abnormal.
Lead author Dr. Michael S. Diamond of Washington University in St. Louis has stated that the Zika virus is responsible for creating major damage on fetal brain. "That's not to say there aren't other factors that may predispose people to get Zika, but you don't need all those things," he said in reference to other possible causes for brain damage.
