In this Wednesday, Aug. 24, 2016 file photo, Aedes Aegypti mosquito larvae swim in a container at the Florida Mosquito Control District Office in Marathon, Fla. A first look at U.S. children who were infected with Zika virus suggests the germ typically causes—at worst—only a mild illness in children, according to a report released by the Centers for Disease Control and Prevention on Friday, Sept. 30, 2016. (AP Photo/Wilfredo Lee)

A first look at U.S. teens and young children who were infected with Zika suggests the virus typically causes at worst only a mild illness.

Zika infection during pregnancy can cause severe brain-related birth defects. But the report seems to confirm ' belief that infections that occur after birth in children are similar to infections in adults—most people don't feel sick, and some develop only mild symptoms.

Some experts say there's not enough data to answer questions about the virus's potential impact on the developing brains of infants and small children, however.

The Centers for Disease Control and Prevention released the report Friday. It's based on 158 infections from earlier this year in kids ages 1 month to 17 years.