On the front lines against Zika, Tampa Bay area mosquito experts are pressing hard

TAMPA

Ron Kolsen takes the cylinder-shaped bag and dumps its contents on a plastic board.

"Alright," he says, staring intently at the pile of dead mosquitoes in front of him. "Let's see what we've got."

Kolsen pulls a magnifying lamp over the tiny corpses to take a closer look. He sees hundreds of them, some with spotted wings, some with black-and-white striped legs. The ones he's looking for have silver-white scales on their backs that look like miniature violins.

"Really, what we do is play detective," he says.

Kolsen is a veteran mosquito inspector. His work has taken on new urgency this summer in the face of Zika, the mosquito-borne virus that has exploded across Latin America and can cause devastating birth defects.

Each Tuesday, he sorts and counts the unlucky insects that wind up inside Hillsborough County's 65 mosquito traps. His findings help the county determine where the mosquito population is thriving — and where to launch all-out aerial and ground assaults on the pesky bloodsuckers.

Local mosquito control experts don't expect a Zika epidemic in the Tampa Bay area; summer is already under way, and nobody has contracted the virus from a mosquito in the United States. Still, the mosquito control departments in Hillsborough and Pinellas counties are working to prevent isolated outbreaks should mosquitoes start transmitting the virus in Florida.

Their strategies: close surveillance and more education.

"We are getting out there and trying to get in front of this," said Rob Krueger, an entomology and education support specialist with Pinellas County Mosquito Control and Vegetation Management.

They'll soon have extra money. On Thursday, Gov. Rick Scott signed an executive order dedicating $26.2 million in state funding to Zika preparedness, prevention and response. The money will support mosquito surveillance and abatement, as well as training for mosquito control technicians, his office said.

Hillsborough County's mosquito headquarters stands in the shadow of the Tampa Executive Airport. The campus is home to a modest office building, 12 spray trucks, an airboat and six noisy chickens used to detect the presence of West Nile Virus.

The 23-person department has a lot of ground to cover: 1,072 square miles, to be exact. That's where surveillance comes in. "Surveillance is the most important thing we do," said Carlos Fernandes, the mosquito control director.

Most of the traps in Hillsborough attract mosquitoes using light and carbon dioxide, and ensnare them in mesh bags. Employees set the traps Mondays and collect them Tuesdays. Back at headquarters, inspectors freeze the captive mosquitoes — dead insects are easier to count than living ones — and determine which traps had a larger haul than usual.

If a trap is full of females, the area around it will be a candidate for spraying. Mosquito control employees will also spray a neighborhood if people complain or a resident has been diagnosed with Zika.

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Technicians can spray from the department's helicopter, specially equipped Ford F-150 pickups or handheld devices. ("Like Ghostbusters," Fernandes said.) They use the least potent EPA-approved insecticides possible to ensure the mosquitoes don't develop a resistance to the chemicals.

Since Zika hit the U.S. news in January, inspectors have been more diligent about monitoring Aedes aegypti (yellow fever mosquito) and Aedes albopictus (the Asian tiger mosquito), the two species that carry Zika overseas. Inspectors use new traps suited for capturing low-flying mosquitoes. And when they catch more than five of either species in one location, they send them to a lab in Kissimmee for Zika testing.

"We're on high alert," said Kolsen, the inspector.

The department has also launched a public education campaign to help people control mosquitoes on their own properties. That is critical because Aedes aegypti and Aedes albopictus prefer to be indoors, "and it is hard to put traps inside people's homes," Fernandes said.

Their advice to homeowners: Dump the standing water in your yard — mosquitoes breed there — and keep your doors and windows closed. You don't want to become a blood meal.

"We are not waiting and watching," Fernandes said. "We are out all the time, collecting information and fine tuning our operation as much as possible."

The operation in Pinellas is similar. Krueger, of the mosquito control department, described it as a "boots-on-the-ground approach" focused on education.

Spraying doesn't always work with Aedes aegypti, he said. He believes urging people to flip their flower pots and empty their bird baths can be more effective.

"This is a highly adaptive, invasive species," Krueger said. "It used to prefer to breed in natural vessels of water. Now, if given the choice to breed in a natural container or a manmade container, it will choose a manmade container."

Though Zika is new to the Western Hemisphere, mosquito control departments in Florida aren't flying blind. They've had to deal with mosquito-borne viruses such as West Nile, Dengue and chikungunya, and have the infrastructure to prevent outbreaks.

"The infrastructure is exactly what makes the difference" between counties like Hillsborough and countries like Brazil that have struggled with Zika, Fernandes said. "We are one of the best-organized mosquito control operations in the country."

A recent Tuesday found Hillsborough's mosquito control headquarters humming with activity. One team prepared for a helicopter spray mission over Apollo Beach. Another assembled in the large conference room.

Kolsen and surveillance manager Leonard Burns worked in the lab. After lunch, they tackled a trap that had been set near Riverview. They didn't find Aedes aegypti or Aedes albopictus — but the 2,500-mosquito haul was enough to catch their attention.

Two days later, as the sun set over a residential neighborhood not far from the trap, a Ford F-150 rolled through the streets, yellow lights flashing. A soft white mist trailed behind.

Contact Kathleen McGrory at kmcgrory@tampabay.com or (727) 893-8330. Follow @kmcgrory.