UW-Madison students helping identify disease-carrier mosquitoes in Texas, post-Hurricane Harvey

Milwaukee Journal Sentinel

Two University of Wisconsin-Madison students are in Texas helping identify the millions of nuisance mosquitoes that are hampering Hurricane Harvey recovery efforts and raising concerns about mosquito-borne diseases as floodwaters recede.

Melissa Farquhar (left) and Erin McGlynn, UW-Madison students, stand outside the Clarke mobile entomology lab, where they are working to identify mosquitoes to assist mosquito-control efforts following Hurricane Harvey.

Erin McGlynn, a medical and master's in public health student from Wisconsin Rapids, and Melissa Farquhar, a veterinary medicine student from San Jose, Calif., are working out of a mobile lab as temporary employees of Clarke, an Illinois-based mosquito control company contracted by the State of Texas.

Clarke is a partner of the new vector-borne disease center housed at UW-Madison, called the Upper Midwestern Center of Excellence for Vector-Borne Disease, where McGlynn and Farquhar are training as part of their studies.

The students flew to Corpus Christi on Wednesday, arrived in Houston on Sunday, and expect to return to Madison on Thursday.

During their week in Texas, they are monitoring for disease-spreading species of mosquitoes and helping determine the effectiveness of control efforts. They told the Milwaukee Journal Sentinel they have identified mosquito species capable of carrying the Zika and West Nile viruses.

But no disease outbreaks have been detected in Texas, post-Hurricane Harvey.

The students said they also are trying to keep up with their studies by watching lectures that are available online.

During the day, they use dissecting microscopes to examine hundreds of mosquitoes that have been trapped by mosquito controllers. The controllers want to know which species of mosquitoes are present to monitor disease potential, and also the density of mosquito populations to help guide aerial spraying efforts, the students said.

Melissa Farquhar, a UW-Madison student, identifies mosquitoes using a microscope near Houston to assist mosquito-control efforts following Hurricane Harvey.

Sunday, the students had mosquitoes from 16 traps under their microscopes. One trap caught 16,000 mosquitoes. The students only identified a representative sampling; not all 16,000. Usually, they look at 400 to 500 mosquitos a day, they said.

So far, they have identified 24 species of mosquitoes they've never seen in Wisconsin. One species was orange and black, and Clarke employees referred to it as a Halloween mosquito.

They also have gone out with Clarke employees to set mosquito traps — nets with lights over them and dry ice that attract mosquitoes by releasing carbon dioxide. The mosquitoes die in the traps.

Monday night, the students planned to see the planes that spray mosquitoes at dusk, when the pests come out in the greatest numbers. Traps are set both before spraying and afterward to judge the effectiveness of control efforts.

The Upper Midwestern Center of Excellence in Vector-Borne Disease was established in January with a $10 million grant from the U.S. Centers for Disease Control and Prevention. The research and training program aims to help stem the spread of diseases such as Zika, West Nile and Lyme, carried by vectors such as ticks and mosquitoes.

The center is a consortium of Midwestern universities, led by UW-Madison medical entomologists Lyric Bartholomay and Susan Paskewitz.