Since the current outbreak of Zika virus was first recognized in Brazil last year, scientists have been steadily uncovering new knowledge about the pathogen, including how it can cause developmental defects in infants born to infected mothers. A new study complements clinical observations of the virus’s effects, revealing that Zika can invade the progenitors of fetal brain cells, and can replicate for weeks in these cells, dodging detection by the immune system.

John Schoggins, a 2015 Rita Allen Foundation Scholar and an assistant professor of microbiology at The University of Texas Southwestern Medical Center, is the senior author of the study, published online on June 3 in Cell Reports. Using a strain of Zika virus isolated in 2015 in Puerto Rico, Schoggins and his collaborators found that the virus infected an average of 20 percent of cultured brain progenitor cells. While some cells were killed by the infection, others survived and allowed the virus to replicate. These surviving cells generated few immune responses to the virus, the researchers reported.

“The cellular system we studied mirrors what pathologists are finding in the brain tissue of affected infants and will be valuable for further understanding how Zika causes severe brain-related problems,” Schoggins said in a news story announcing the findings. “The system may also serve as a platform for testing new therapies targeting the virus.”