Almost a third of children aged 3 years and younger who were exposed to Zika virus during their mother’s pregnancy had below-average neurological development, a recent study published in Nature Medicine suggests.

“Long-term follow up is needed for children who are exposed to maternal infections duringpregnancy, especially viruses that are novel and others that are known to be teratogenic,” lead author Karin Nielsen-Saines, MD, MPH, the study’s lead author and a professor of clinical pediatrics at the David Geffen School of Medicine at the University of California, Los Angeles, told Infectious Diseases in Children. “Repercussions of in utero infection may not be apparent at birth, they can manifest later, and following neurodevelopment and neurosensory function in the first years of life all the way through the early school years is important.”