PIXABAY, M. AMEENAs researchers continue to identify the full range of diseases that are linked to maternal Zika infection, reports this week indicated that microcephaly is only one of numerous Zika-associated birth defects, and that the virus can replicate and persist in the fetal brain.
A study of Brazilian Zika cases published in The New England Journal of Medicine found that 42 percent of newborns whose mothers had been infected with the virus showed serious birth defects. Microcephaly accounted for just three of the 42 percent, whereas other birth defects such as low birth weight and central nervous system abnormalities made up the bulk of adverse pregnancy outcomes.
“Microcephaly is just the tip of the iceberg. It’s definitely not where the focus should be,” coauthor Karin Nielsen-Saines told STAT News. “For every case of microcephaly you’re probably going to have 10 cases of other problems that haven’t been recognized.”
A second study clarified the role that Zika plays in these birth defects. A team of researchers write in Emerging Infectious Diseases that the virus not only persists in an infant’s brain tissue after birth—it replicates 1,000-fold.
“We don’t know how long the virus can persist [in infants],” Centers for Disease Control and Prevention researcher Julu Bhatnagar said in a statement, “But its persistence could have implications for babies born with microcephaly and for apparently healthy infants whose mothers had Zika during their pregnancies.”