The Florida Department of Health is urging residents to be mindful of exposure to mosquitoes and issued a statewide health advisory after four confirmed cases of malaria in Sarasota County.
The agency says all of the individuals who contracted the disease were bitten by a mosquito or mosquitoes in the Sarasota area.
This is unusual because a vast majority of malaria cases in the U.S are detected after someone has traveled to another country. According to the Centers for Disease Control, the local cases are the first in the United States since 2003.
This week, a health alert issued by the Centers for Disease Control and Prevention also noted that another case has been detected in Texas.
Christopher Uejio is an assistant professor at Florida State University. He studies mosquito-borne illnesses and says the outbreak is concerning but that the disease is treatable.
"This form of malaria is not as vicious as some of the ones that are in others part of the world,” he said. “But that being said, we want to be vigilant but not necessarily panic."
Uejio says common symptoms of malaria include flu-like symptoms including muscle aches, fatigue and nausea.
“One of the tell-tale signs is this sort of periodic alternation between fevers and sweats and chills about every eight to twelve hours and that actually corresponds to the parasite expanding and exploding some of your red blood cells in your body," he said.
Residents should take precautions like applying mosquito spray, avoiding areas with high mosquito populations such as retention ponds, and wearing long pants and shirts when possible - especially during sunrise and sunset when mosquitos are most active.
Officials continue to conduct ground and aerial pesticide treatments to kill mosquitoes in Sarasota and Manatee Counties.
Chris Lesser, director of the Manatee County mosquito control district, said they're primarily using helicopters to combat the mosquito population because they cover between 15,000 and 20,000 acres (6070 to 8082 hectares) in one night. A truck can only cover around 1,000 acres (404 hectares) a night, he said.
“We really want to focus on killing the adult mosquito before they have the opportunity to feed on one person that may be infected with malaria and then transmit that disease to a second person,” Lesser said.
He said the time frame for when a mosquito can become infected to when it can transmit the disease to a person is about 14 days.
“So we’re trying to get in there about once every seven to 10 days and really knock down the mosquito population. And that process will continue until the public health alert that we’re currently under is lifted,” Lesser said.
“It's a curtain,” he continued. “We're trying to keep the malaria mosquitoes from coming into our county through our southern border by using aggressive mosquito control activities.”
Officials in Sarasota County area also using similar tactics to control mosquitoes, the county's health department said in an advisory.
The threat of the mosquito-borne illness concerns Kathleen Gibson-Dee, who lives on Terra Ceia Island in Manatee County.
Even though no malaria cases have been reported in Manatee, Gibson-Dee said that she's now routinely using bug repellent while working in her garden.
“I don’t go out without it,” she told The Associated Press on Tuesday. “And we don't go out in the evening because you can see clouds and clouds of bugs now. They may not all be mosquitoes, but there’s certainly mosquitos out there.”
Another resident, Tom Lyons, says news of the malaria cases “makes me take mosquito protection a little more seriously."
The mosquito population thrives in Terra Ceia because "it's an island surrounded by a lot of shallow water and mangroves, and ideal places for mosquitoes,” Lyons said.
The initial malaria advisory was issued in Sarasota County after the first case was reported in late May. That was followed by a second case, and then two more, said Jae Williams, the press secretary for the Florida Department of Health.
“As soon as it crossed over from one to two confirmed cases, it progressed to an alert,” Williams said, comparing it to the system of issuing a hurricane watch versus a hurricane warning — when a storm is imminent.
“Listen, the conditions are favorable," Williams continued. "It's not just some rogue one mosquito. People need to be paying attention.”
Williams said health officials are being proactive.
“We know we are going into the Fourth of July holiday. We know the summer’s only getting hotter and wetter over the next couple of months,” Williams said. “So we just wanted to give Floridians a big kind of heads up, put the whole state on notice.”
About 2,000 U.S. cases of malaria are diagnosed each year — the vast majority in travelers coming from countries where malaria commonly spreads.
Since 1992, there have been 11 outbreaks involving malaria from mosquitoes in the U.S. The last one occurred in 2003 in Palm Beach County, where eight cases were reported.
Information from the Associated Press was used in this story.
