Researchers study why mosquitoes excel at sucking

Zach Nemitz and Ruby Ramos examine bacteria as part of mosquito research at USF
Sarasota-Manatee. PHOTO PROVIDED BY KRISTA SCHROCK

For most people, the key to keeping mosquitoes away during the summer lies in a can of bug spray. However, there may come a day when a generous amount of DEET is not enough to protect a backyard barbecue.

Aparna Telang, an assistant biology professor at USF Sarasota-Manatee, began working with student researchers this month to develop a natural, more effective way of quelling Florida’s mosquito population, which consists of more than 80 species. 

Mosquito control is a costly endeavor in Florida, and Tom Unnasch said in a USF Health article published in April that the state spends about $75 million to $100 million each year on mosquito control. This is largely due to the potentially life-threatening diseases spread by mosquitoes, like West Nile virus and malaria.

“Overall, when you’re a researcher in a mosquito area, your primary goal is to figure out safer, better ways to control their population,” Telang said.

According to Telang, these new biological methods of mosquito population control are important because of how easy it is for mosquitoes to gain resistance to conventional repellents and chemicals.

“Most researchers, not just me, are looking for better bio-control methods,” Telang said. “We’ve seen that throughout history, mosquitoes have gained resistance to chemicals.”

In order to determine what can be done to control mosquitoes from the inside out, Telang and four USF biology undergrads — Ruby Ramos, Zach Nemitz, Carissa Santiago and Nicole Carswell — will investigate how parasites live inside mosquitoes and why mosquitoes are able to live despite containing viral diseases.

The team’s most important tools include two refrigerator-sized, light and temperature programmable mosquito incubators where hundreds of mosquito eggs will be reared for testing, a micro-injector for collecting mosquito immune cells and high-powered microscopes used for dissecting the mosquitoes and inspecting their stomachs and reproductive organs.

“I train (the students) on the…different tools we use to (examine) the inside of the mosquito,” Telang said. “Once you have the mosquito open, you can then target particular organs. Like all animals, they have very specific organs inside of the overall body that we see. … We focus on tissues, organs and cells for pretty much all my work.”

Each of the four student researchers will also have their own tasks to perform within the study. Ramos, for example, will be feeding dog blood infected with malaria worms to mosquitoes in order to observe how the insect’s immune system responds to parasites.

Ramos said she joined the research project to learn more about the immune responses of mosquitoes, as well as seize an opportunity for hands-on lab experience.

Nemitz and Santiago will collaborate with Kim Ritchie, a microbiologist at the Mote Aquaculture Research Park in eastern Sarasota County, in order to closely examine the microbial population naturally residing in mosquitoes.

Nemitz, who is going into his senior year, said he is interested in the project not only to gain lab experience but also because he feels this topic hasn’t been investigated to death by previous researchers.

“There’s a lot of information out there that hasn’t really been seen,” Nemitz said. “I really hope to (find) some kind of neat, undiscovered information there.”

Carswell will work with Manatee and Sarasota mosquito control offices to better understand how the West Nile virus, as well as the lesser-known St. Louis encephalitis virus, are transmitted by birds.

Telang said since the ultimate goal of this study is to figure out a safer, more effective method of keeping mosquitoes’ numbers in check, discovering a reliance the insect has on a certain strain of bacteria could lead to the natural solution the researchers are looking for.

She said the question that would then follow is if the team can figure out which bacteria mosquitoes rely upon for their superhuman disease resistances, can researchers utilize that knowledge to make it harder for them to survive in a population?

This question may have to wait until the research project is well past its first few years, as Telang said while she hopes to have findings published from this study over the next year or two, she considers the project to be a long-term endeavor and plans on taking in more student researchers throughout the years of the study’s existence.

“As a scientist, I don’t really see anything as final, so I am hoping that we get enough work done over the next year or two to publish what we know so far, but … when you find some answers, you usually come up with more interesting questions, and that keeps your research moving forward,” Telang said. 

“I anticipate taking students on year after year…which is good because that means there’s never a shortage of ideas that students can get into the lab and join in on that effort.”