No new local malaria cases reported since July 13

Although no new cases of malaria have been reported in north Sarasota since July 13, Sarasota County’s Mosquito Management Department is still working diligently to eradicate the affected mosquito population that has infected seven people.

Those cases were all reported in the Desoto Acres and Kensington Park areas; three of the victims are homeless individuals. 

During a Thursday morning media update hosted by the Centers for Disease Control and Prevention and Sarasota County government, officials reported it will take another four weeks of no new reported locally transmitted cases before the outbreak can be declared officially over. 

Presuming no new cases are reported, the target date is Sept. 7. The first case was reported on May 24.

The most recent previous malaria outbreak in Florida was in 2003 in Palm Beach County.

Jamie Carson, the county’s director of communications, said Mosquito Management Services is pulling out all the stops to control the outbreak.

“We're using not only larvicides and adult spraying, but we're also out there providing surveillance and field operations and utilizing mosquito fish as well,” Carson said. “We’ve supplied the local ponds and the standing water areas where this particular mosquito might breed with over 15,500 fish at 22 sites. The Mosquito Management Services team is using everything in their arsenal to lower the mosquito population, and are especially focused in this area.”

Audrey Lenhart, chief of the Entomology Branch in the Division of Parasitic Diseases and Malaria at the CDC who joined the virtual meeting from Ghana, brought the science to the discussion. Via sequencing of the genome of parasites found in both patients and in the mosquitoes, she confirmed the outbreak is a closed transmission loop.

“That just increases our level of confidence that it was a closed transmission loop that, once we don't see any more cases, the transmission has truly stopped,” Lenhart said. “Mosquitoes don't live a tremendously long time, so we have to think in terms of when a mosquito could have potentially bitten someone that had malaria and then how long it would take for that mosquito to die. 

“A typical mosquito will live maybe three weeks, but they can live up to six or eight weeks, so every day that goes by gets us closer to feeling confident that the transmission cycle has been interrupted.”

Carson cautioned that residents in the affected areas should continue to be vigilant in avoiding mosquitoes and eliminating breeding areas by emptying any outdoor containers and other objects that hold standing water. They should also wear long sleeves and pants and use insect repellants on exposed skin.

Lenhart said the outbreak has been well contained so far thanks to the actions of the Mosquito Management Services staff.

“It really is an exceptional operation that Sarasota has for mosquito control,” she said. “And it's a tribute to their fast action and continued action that the mosquito populations were reduced significantly and that this outbreak wasn't worse than what we've seen.”