Mosquitos don’t show up in most people’s top 10 lists of dangerous animals, but they should. These tiny insects transmit diseases that kill more humans than any predator on Earth. Tragically, lower-income people face a greater risk of mosquito-borne illnesses than wealthier individuals, and research by Sarah Rothman is unraveling some of the reasons for that inequity in urban environments.
Rothman is a PhD candidate in AGNR’s Department of Environmental Science and Technology. Building on research by her mentor, Professor Paul Leisnham—who showed that mosquitos in Baltimore, Md, are more numerous and live longer on blocks with more lower income residents—Rothman found those mosquitos are also more likely to carry West Nile Virus, the most common mosquito-borne disease in the continental U.S.
To understand why, she turned to the source of mosquito food, dead and decaying plant leaves that teem with microbes. Rothman’s surveys of Washington, DC, and Baltimore City found that the most common plant species on low income blocks were non-native, while high-income blocks hosted mostly native species. That was key information, because previous laboratory studies showed that non-native plants result in faster-growing, larger mosquitos, and they support the coexistence of two mosquito species that contribute to the spread of West Nile Virus among humans.
Rothman’s work is the first to put all these pieces together, and her studies suggest that managing plant species on a city block could potentially reduce exposure to mosquito-borne illness.
Rothman’s presentation of her research won the UMD three-minute thesis award, a competition that challenges PhD students to present their work and its impact for a general audience in just three minutes. But she said the greater reward is in knowing her work may have an impact.
“I knew getting a PhD would be hard, “Rothman said, “but when I discovered the work that Dr. Leisnham was doing, I was really intrigued by the opportunity to do applied research that was important for public health and for environmental justice. It's unjust that certain communities by nature of where they live would be put at a greater risk of exposure to mosquito borne illness. I knew that would motivate me to see it to the end and to keep working on it despite any challenges that would come up.”
You can see Rothman’s three-minute thesis video here: go.umd.edu/AGNR3mt.
by Kimbra Cutlip : Momentum Winter 2023
