Health officials said they are probing a Florida case of Zika that may have been transmitted through a mosquito born in Miami-Dade County—possibly the first “non-travel” case detected in the continental U.S. The county already had the most travel-related cases of the virus in Florida—88. Zika can also be contracted through sex. The virus can create serious birth defects in fetuses, including microcephaly, which is characterized by an underdeveloped brain. More than 1,300 Zika cases have occurred in the U.S., but this would be the first infection contracted directly from a mosquito. Almost all of the other cases were contracted while traveling in a country where the virus is more prominent.