Student-Led Public Health Research Targets Mosquito Hotspots

As temperatures spike each spring, mosquitos start to swarm. They bring with them an increased risk of mosquito-borne diseases and a need to understand how to guard against these pesky – and at times –dangerous insects.

Researchers at UNC Charlotte and the Mecklenburg County Health Department are collaborating on a study to determine which factors in the environment lead to hotspots of mosquito activity – and they need help from the public.

“Our research is focused on understanding the types of features that mosquitoes are looking for when selecting where to breed in cities,” said Ari Whiteman, a UNC Charlotte student in the Geography and Urban Regional Analysis doctoral program. “This is one of the best ways to predict where mosquito-borne disease outbreaks are most likely to occur.”

Whiteman, who is founder and director of the Urban Mosquito Project, is seeking volunteers in the Charlotte area who will allow the research team to place mosquito traps on their property.

“We will be undertaking a massive mosquito survey effort across the county this summer,” he said. “This will involve setting up mosquito traps across the county in a wide variety of locations, such as high and low income, high and low vegetation cover and high and low temperature areas. We will also be on the lookout for existing breeding containers across those same locations.”

The traps will be set up in mid-June 2017 and will remain on each volunteer’s property until August.

“We use black plastic buckets that attract gravid, or pregnant, mosquitoes and then trap them in a sticky card placed at the bottom,” Whiteman explained. Researchers will come by weekly to replace the sticky card and shift the traps to a new location on the property.

The project also needs volunteer research assistants to interview residents who live near the trap sites to gain an understanding of the residents’ knowledge of mosquito-borne disease risks.

The study focuses on Aedes mosquitos, which are responsible for transmitting Zika virus, Dengue fever, Yellow fever and Chikungunya virus. Combined, approximately 500 million cases of these diseases occur worldwide each year. Aedes mosquitos often lay their eggs in landscape features that hold water and in man-made containers, such as pet water bowls, flowerpot saucers, buckets and birdbaths.

“Urban areas represent an interesting and relevant setting for this type of research because of the high concentration of both people and mosquitoes,” Whiteman said. “This makes cities the most at-risk environments for the ever-increasing threat of mosquito-borne disease transmission.”

Whiteman is collaborating with Dan Janies, Carol Grotnes Belk Distinguished Professor of Bioinformatics and Genomics. Janies and his students will perform genetic sequencing on extracts from mosquitos’ contents to check for the presence of viruses. If viral sequences are detected, Janies’ group can identify to which lineages the viruses belong and put all this information in context with bioinformatics and geoinformatics software they have developed. This software helps Janies’ group to assess the origins, spread and risk of various viral lineages.

Eric Delmelle of the Department of Geography and Earth Sciences in the College of Liberal Arts & Sciences, Whiteman’s mentor and academic advisor, is contributing to the research. He previously has mapped Dengue Fever and Zika outbreaks and is an expert in health geography. He is advising Whiteman on the best sites to set up the mosquito traps.

“One of our core questions is whether the mosquito populations vary across a socioeconomic spectrum,” Whiteman stated. “Are low income communities more or less likely to experience mosquito-borne disease transmission than high income communities? We already know that the composition and structure of the environment varies quite substantially between high and low income areas, yet we’re not sure if mosquitoes are affected by those changes.”

The study will examine other factors that are predictors of mosquito hot spots, such as vegetation, weather and people’s knowledge about mosquitos and the diseases they can spread.

Mecklenburg County Department of Health has provided institutional and financial support to the project due to its potential for predicting areas of possible disease outbreak. Physician Michael Dulin is facilitating the collaboration between UNC Charlotte and the health department. Dulin leads the Academy for Population Health Innovation, a partnership between the health department and the UNC Charlotte College of Health and Human Services.

“This is a wonderful example how the new partnership between UNC Charlotte and the county’s public health team advances the health of our community by proactively developing an understanding of where potential disease outbreaks could occur and appropriately informing future counter measures,” Dulin said.

Using statistics and modeling, the researchers will develop risk of disease transmission maps for the county, which will highlight where outbreaks are most likely to occur. These maps will help direct further surveillance efforts, mosquito eradication programs and education campaigns about mosquito-borne diseases.

The findings will be shared with VectorMap, a global database of mosquito samples. VectorMap is operated by the Walter Reed Biosystematics Unit at the Smithsonian Institution. It is a unique global resource for researchers interested in mosquito-borne diseases and basic questions concerning mosquito distribution and ecology. Scientists and researchers use this database worldwide to combat mosquito-borne diseases.

“Preventing an outbreak is always preferred over treating one,” Whiteman said. “With the threat of Zika virus and other mosquito-borne diseases on the horizon, we hope to use our results to effectively reduce pathogen exposure risk throughout the Charlotte region.”

by: Jennifer Howle