West Nile Infects Human Placenta (IMAGE) Washington University School of Medicine Caption West Nile virus (green) grows in human placenta, where the cells are marked red with blue nuclei. A study has found that viruses related to Zika, such as West Nile, can cross the placenta in mice and cause fetal brain damage and death. Credit Nitin Arora Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.