Zika-caused birth defect may become clear only after birth
Researchers say a severe birth defect caused by Zika infection may not be apparent at birth but develop months afterward, further confirmation that the virus can cause unseen damage to developing babies.
The findings come from a study of 13 Brazilian babies whose heads all appeared normal at birth but then grew much more slowly than normal.
Most people infected with Zika never develop symptoms, but infection during pregnancy can cause devastating birth defects, including microcephaly, in which a baby’s skull is much smaller than expected because the brain hasn’t developed properly.
Microcephaly is diagnosed based on a measurement of the baby’s head circumference. It can be done during pregnancy using ultrasound, or after the baby is born. Doctors then compare the measurement to standard sizes of other kids, based on gender and age.