UF doctoral student uses high-tech method to solve Greece's tough mosquito problem

October 27, 2008

GAINESVILLE, Fla. — A University of Florida doctoral student from Greece is helping her country control its massive mosquito problem by using a high-tech, environmentally friendly system that uses a helicopter to spray tiny amounts of insecticide into precision-targeted areas.

Alex Chaskopoulou spent the summer overseeing an experimental mosquito control program, and now Greek government officials are pushing for the program to be rapidly expanded. She sent a formal report on her work to the Greek minister of agriculture two weeks ago.

“There was a need and I thought I could do something different that would make a difference and provide a significant help in Greece,” Chaskopoulou said. “You cannot imagine how bad the mosquitoes are in Greece.”

In parts of northern Greece, it’s not unusual for more than 100 mosquitoes to bite a person in a minute’s time, she said.

Working with entomologist Phil Koehler of UF’s Institute of Food and Agricultural Sciences, Chaskopoulou began researching methods for targeting the mosquito problem in Thessaloniki and nearby Chalastra, parts of Greece hardest hit by the insects because of nearby rice fields.

Greek officials had been focusing on killing mosquito larvae but were thwarted when the European Union banned the most effective insecticides.

Chaskopoulou and Koehler agreed on attacking adult mosquitoes with a cutting-edge method rarely used in the U.S. and never before used in Europe or Asia.

The procedure combines a helicopter equipped with Global Positioning System technology, real-time meteorological equipment and computer modeling systems to deliver extremely minute but effective amounts of mosquito insecticides to precise areas. The equipment reads weather conditions and tells the pilot, via the GPS screen, precisely when and where to spray. Just one-half gram per acre — about the weight of an aspirin tablet — is diluted by water and air into a fine mist that settles over an exact area predicted by the computer.

Adding to the challenge, spraying had to be done at night when adult mosquitoes are most active.

After three years of planning that included arranging for technicians who could travel to Greece to assemble the equipment, Chaskopoulou went to Chalastra in June.

She set up mosquito traps in the 2,400-acre area where spraying would be allowed. The spray area had to be at least three kilometers, or 1.86 miles, away from homes. Before spraying, the traps snared as many as 20,000 mosquitoes at a time.

Before the first trial began in late July, Chaskopoulou and the pilot — her father, Efthimios — did practice runs by spraying water. Flying at 100 mph just 200 feet off the ground at night can be dangerous, and she said once the trials began, she could only listen for the helicopter to gauge his progress, and his safety.

“My heart would pound until it was over,” she said.

Adding to the stress, the 27-year-old had an entourage of government officials and manufacturing company representatives keeping tabs on her work. Many times, up to seven carloads of officials followed her progress.

“I was terrified,” she said.

She couldn’t let them wear insect repellent because it might taint the study’s results, so the men mostly stayed in their cars to avoid the biting insects.

The study’s results were strong, with an average 80 to 93 percent decrease in the number of mosquitoes caught in the area during the 24-hour period after a spraying. Her study also looked at how the sprays affected nontarget organisms, including beneficial semi-aquatic beetles that eat mosquito larvae. The beetles were unaffected.

Chaskopoulou’s work cost the Greek government between $1 million and $2 million, from planning to execution, Koehler said. But by all accounts, it’s worth it. On Sept. 26, Koehler and Chaskopoulou attended a banquet hosted in their honor.

Seated next to Chalastra’s mayor, Koehler said the mayor was effusive, telling him the reduced numbers of mosquitoes were “’the best thing since DDT and penicillin.’ Not just one or the other. Both.”