NEWS BRIEF Florida health officials are investigating five new cases of Zika in the state that are not a result of travel outside of the United States, but of local transmission of the virus, the governor’s office said Tuesday.

One case is in Pinellas County and four are in Wynwood, the neighborhood where officials found in late July the first signs of local Zika transmission on American soil; at the time, four people were confirmed to have contracted the virus while in Florida. Before that discovery, people in the United States who tested positive for Zika had been infected while traveling to countries where the virus is present, or by engaging in sexual contact with infected individuals. The appearance of local transmission in Florida meant that Zika-carrying mosquitoes were active there.

The latest cases of local transmission bring the total in Florida to 42, according to officials. The virus thrives in warm, humid weather and in densely populated areas, and researchers predicted it could reach parts of southern U.S. states this summer.

Florida officials believe local transmission is limited to Wynwood and Miami Beach, where similar cases were reported for the first time last week. Officials have combated the presence of Zika-carrying mosquitoes by spraying affected areas with insecticide. The Centers for Disease Control and Prevention has warned pregnant women, for whom Zika is understood to be most dangerous, to avoid those areas. The virus, which emerged in Brazil last year and has quickly spread to dozens of countries, can cause microcephaly, a condition in which babies of infected mothers are born with abnormally small heads and neurological defects. Brazil has reported more than 1,700 confirmed cases of microcephaly since the outbreak began in 2015.

Florida health officials are offering free Zika testing and prevention kits to pregnant women in Pinellas County. There is no treatment or vaccine for the Zika infection, but scientists around the world have fast-tracked medical research of the virus.