Students Help Identify Mosquitoes with VirusNov 15th, 2003 | By jmckee | Category: 15-2: Reclaiming Native Health, Tribal College News
From a watery, brown drop of concentrated mosquito genes, Montana state scientists identified the first batch of mosquitoes known for sure to carry the sometimes-deadly West Nile virus in Montana. The mosquitoes were found by student interns at Fort Belknap College (Harlem, MT) working with the state under a federal grant.
What they found are no ordinary bugs. The vast majority of Montana’s mosquitoes are of the genus Aedes sp. (pronounced “eighties.”) The mosquitoes found to be infected this week were the less common Culex sp. variety, the kind of mosquito most closely linked to West Nile transmission.
This discovery is a victory, said Susie Zanto, technical manager for the state’s public health lab. It shows that the web of mosquito traps and trappers making up Montana’s public health surveillance system is working. “This is the fruition of everything we’ve worked for,” Zanto said.
On the front lines, Montana’s mosquito surveillance system is tedious and swat-filled — just ask Tessa Clairmont, 19, or her colleagues, Kristie Crazy, 24, and Lacy Horn, also in her early 20s. All three Fort Belknap College interns catch mosquitoes all day. From the state, they receive “dry ice” catchers — conniving little mosquito traps that prey on mosquitoes’ greatest weakness: their universal attraction to carbon dioxide, the stuff people and all other mammals exhale when we breathe out. In a green canister above a cone-shaped net, Clairmont, Crazy, and Horn place chunks of dry ice. When it sublimates, it gives off carbon dioxide gas. The bugs go in for the kill and get sucked into the net by a weak fan.
The students, working under Liz McClain, a professor at the college and coordinator of the school’s aquatic studies, hang the traps in campgrounds and picnic spots and collect hundreds of mosquitoes each night. Another student has the task of manually sorting the mosquitoes by genus.
McLain, who worked for years on malaria and plague research in Africa, said Montana has a ways to go to fully ramp up public health surveillance. Don’t wait for a crisis, McLain said, having lived through malarial outbreaks before. “You can’t tell anything in an outbreak,” she said.
McLain has even broader hopes. She and her students are not just trapping mosquitoes. For their own research and to build a record for Blaine County, they are looking for mosquito larva — which can be more easily killed than adult, flying mosquitoes — by applying a natural pesticide to standing pools of water. “It’s labor-intensive, and it’s expensive,” she said, “but not as expensive as trying to kill the adults.”
Reprinted with permission from the Billings Gazette.