EXCHANGE Illinois St. Researcher in War Against Mosquitoes

By LENORE SOBOTA, The Pantagraph

NORMAL, Ill. (AP) — In the war against disease-carrying mosquitoes, Steven Juliano considers himself part of the intelligence brigade.

"I don't do mosquito control," said the distinguished professor of ecology at Illinois State University. "I provide the information on where they're vulnerable."

Juliano has received a three-year, $435,000 grant from the National Institutes of Health to study the best time in a mosquito's life cycle to kill them without the unintended consequences of surviving mosquitoes becoming stronger or even more numerous — what's called "overcompensation."

The four mosquitoes targeted in Juliano's research carry viruses that cause diseases such as Zika, West Nile encephalitis, LaCrosse encephalitis, yellow fever and dengue.

Juliano and the students assisting him are "investigating the paradox that if you try to kill larvae, but don't kill every last one of them," the survivors benefit and "you have the potential to make bigger mosquitoes and even more mosquitoes."

To continue the war analogy, attacking larvae at the wrong time could result in winning a battle but losing the war.

Juliano compared it to what happens when you plant seeds. If the plants that sprout are too numerous, they crowd each other out competing for resources, but if you thin them out, the surviving plants grow bigger and stronger, he explained.

"The same thing happens with mosquitoes," he said.

With plants, that's a positive outcome — but not with disease-carrying mosquitoes.

According to the latest figures from the Centers for Disease Control and Prevention, there have been 1,264 cases of West Nile Virus disease in the United States so far this year, resulting in 49 deaths.

The CDC also reports 128 cases of locally acquired mosquito-borne Zika virus disease in the United States this year — all in Florida — and 3,807 travel-acquired cases.

Research already is underway in a lab in the Felmley Hall of Science Annex that is filled with what resemble kitchen refrigerators — except for the more sophisticated temperature controls and signs that prohibit food storage.

Open the doors and you'll find test tubes and other containers in which mosquito larvae and adult mosquitoes are growing. These include larvae of a harmless-to-humans mosquito that eats other mosquito larvae.

The researchers are "imposing mortality" — killing mosquito larvae — in the lab in a controlled way, either early or late in the development cycle and at different percentages, explained Juliano.

They are studying not only how the timing affects the development of the survivors, but also whether, as theorized, different species respond in different ways, he said.

Juliano and his students also will work in the field to see whether the effects are the same as they are in the lab. The field work will be done in Central Illinois, St. Louis and Florida, he said.

Another reason for the grant is to train students to do research — something ISU has done well, especially in the biology department, according to Juliano.

"That's the long-term future of scientific research," he said.

Four graduate students and several undergraduate students will be involved in the project.

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Source: The (Bloomington) Pantagraph, http://bit.ly/2es1QpF

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Information from: The Pantagraph, http://www.pantagraph.com