More than 270 pregnant women in the United States and its territories have tested positive for the Zika virus, according to a report from the Centers for Disease Control and Prevention. Among the 157 women in the U.S. with the virus, only 49 percent reported symptoms, which include rash and fever, according to the CDC. But 66 percent of the 122 residents in U.S. territories reported symptoms. "One challenge of this Zika virus outbreak is the lack of understanding of the magnitude of risk and spectrum of outcomes associated with Zika virus infection during pregnancy," the CDC said in the report. Zika is linked to microcephaly in newborns, and birth defects may be just the beginning of the virus' impacts on infants, FierceHealthcare previously reported. Report (.pdf)