Paddy McManus
Paddy McManus

“Kiddie pools” on campus? Not really. That’s Paddy McManus’s user-friendly way of referring to a research facility often overlooked by much of the U of G community. But it’s been a vital tool for his master’s degree studies intended to help refine a new treatment for controlling disease-bearing mosquitoes.

No kids’ stuff here, says McManus. “Mosquitoes are the most dangerous organism to humans out there, hands down, in terms of yellow fever, West Nile virus, malaria, dengue fever.”

He has worked with Prof. Chris Hall, School of Environmental Sciences, on a project with a Guelph company testing a new formulation to control the insects.

“Researchers are constantly looking for new types of chemical controls to knock back disease vectors,” he says.

Pestalto Environmental Health Services Inc. had already devised its new product. Before getting federal regulatory approval, it needed to know more about how the compound worked under different water conditions, including temperature, hardness and salinity.

That’s what brought the firm to the University in 2009.

McManus had completed a B.Sc. in environmental toxicology in 2009. He started as a technician on the project and began his master’s degree in 2010; he will finish his studies this semester.

For his field work over two summers, he used the U of G mesocosm facility in the Guelph Turfgrass Institute. That facility consists of 30 sunken pools, each four metres across and one metre deep.

Water pumps separately through each “kiddie pool” in the array. That allows researchers to vary conditions in each pool and to test effects separately.

McManus used half of the pools, adding the company’s product to each one. Resembling yellow chocolate chips, it’s made in a wax formulation that dissolves in water. It’s designed to kill larvae in standing water.

He collected water periodically from July through October. That was long enough for various things to enter the pools, including aquatic plants, plankton, insects, even goose “fertilizer.” Says McManus: “One fish ended up in one mesocosm accidentally.”

In the lab, he tested the water on mosquitoes raised from eggs in the nearby biocontrol building. He and another researcher fed adult mosquitoes by sticking their bared arms into an enclosed container swarming with the insects.

He used the yellow fever mosquito, or Aedes egypti, found in the tropics. “That’s the species that is one of the biggest problems for malaria and dengue fever.”

That species is not normally found in Canada.

McManus says the contained insects posed no human or environmental health threat. In other parts of the world, the mosquito transmits endemic disease-causing organisms by feeding on various hosts.

He was able to detect the company’s product in the water, and showed that it inhibited mosquito development.

The product was registered for use by the United States Environmental Protection Agency in 2012. It’s due for registration this summer by Health Canada’s Pest Management Regulatory Agency. “It’s great to see positive results from the work we’ve been involved in,” says McManus.

The company will use his data to set dosage levels and to conduct field trials.

He discussed his project at the annual meeting of the American Mosquito Control Association in February.

McManus grew up in the Ottawa Valley. A camping and hiking buff, he plans to cycle with friends between Guelph and Thunder Bay for two weeks this summer.

Won’t he encounter a lot of mosquitoes en route? Yes, he says, but the trick is to ride faster than the critters can fly. “You just have to make sure you’re biking 12 kilometres an hour.”