By Julie Steenhuysen CHICAGO (Reuters) - Thirteen babies in Brazil born with normal head circumference have been diagnosed with congenital Zika syndrome, with brain scans showing extensive malformations, inflammation and reduced brain volume, researchers reported on Tuesday. Of the 13 infants, 11 gradually developed the birth defect microcephaly, or abnormally small head size, in the months following birth. The findings raise new concerns about the hidden effects of pre-natal exposure to the mosquito-borne Zika virus, which has been shown to cause birth defects when women become infected during pregnancy.
