WNC risk high for La Crosse encephalitis says WCU mosquito expert
Students Evan Joseph (left) and Madeleine Craig, along with other team members have been hatching eggs and studying the larvae and the different life cycles as well as seeing if any of the mosquitoes they caught carry La Crosse.
By Julia Duvall
Cases of malaria in Texas and Florida have been in the news recently and with the warmer, wet weather in Western North Carolina, it is important to be mindful of personal protection from mosquitoes in this region that could carry La Crosse encephalitis.
“The risk for malaria in our area is low,” said Brian Byrd, professor of environmental health sciences and supervisor of the Mosquito and Vector-Borne Infectious Disease Facility in the School of Health Sciences at Western Carolina University. “But La Crosse encephalitis is the most common mosquito-borne disease in North Carolina and predominately affects children in WNC counties, so it is important to remember the three ‘Ds’ of mosquito protection: ‘dress, drain and defend.’”
Byrd and other health officials stress drain or cover standing water; dress in loose, light-colored long sleeve shirts and pants; and defend by using a repellant recommended by The Centers for Disease Control and Prevention.
Byrd and his team of current students and recent graduates have been working diligently the past week surveilling for mosquitoes at various spots on campus and doing studies to determine which mosquito traps work the best.
WCU alum Mitch Mullen is helping professor Brian Byrd and his team of current students and recent graduates have been working diligently the past week surveilling for mosquitoes at various spots on campus and doing studies to determine which mosquito traps work the best.
Typically, La Crosse has mild or no symptoms, but when the brain swells, causing encephalitis, things can take a deadly turn. According to the CDC, symptoms of La Crosse encephalitis include a fever that lasts 2-3 days, headache, nausea, vomiting, fatigue and lethargy. More severe symptoms, which are signs of encephalitis, include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, seizures, muscle weakness, vision loss, numbness and paralysis.
Byrd and his students have been doing mosquito research since 2008 and received a $150,000 grant in 2022 to further their efforts.
The team working on the most recent trap study includes Madeleine Craig, a rising junior from Sylva studying molecular biology and WCU alumni Evan Joseph, Mitch Mullin and Daygan Shouse.
Over the course of four days, the team filled up coolers with dry ice to attract the mosquitoes to the traps and went out into the field twice per day to check and see which traps were most successful in catching the mosquitoes.
The team has also been hatching eggs and studying the larvae and the different life cycles as well as seeing if any of the mosquitoes they caught carry La Crosse.
“We put traps out at four different locations and four different sites within the locations,” Craig said. “We rotated the traps at each site, each day. We put the traps out at 2 p.m. and came the next morning around 9 a.m. to do the collecting.”
The traps typically caught 5-13 mosquitoes and the point of the study was to see which traps collect the most.
Students Madeleine Craig (left) and Daygan Shouse are studying mosquitos at various spots on campus.
“The Aedes triseriatus or Eastern Treehole mosquito is the mosquito that carries La Crosse and is attracted to stagnant water for breeding,” Craig said. “So tree holes and other containers with stagnant water are their go-to places to breed and lay eggs.”
The team used one of the standard traps used by the CDC for surveilling and monitoring other insect borne diseases as a standard to compare the other traps to.
“This type of trap is featured in a lot of other trap studies, so it is a good standard to use,” Craig said. “While it does not typically attract mosquitos with La Crosse, it is a universal standard and that helps us with data collection.”
When asked what the most rewarding and interesting aspects of this research was, the answers from the team varied from the science behind it to being part of prevention efforts.
“Seeing people’s actual experience with La Crosse and knowing that I have helped in prevention efforts is very rewarding,” Mullin said. “It is also interesting to see the life cycle and phases and ecology of mosquitoes and other insects.”
