Research leads to reduced risk of local mosquito-borne diseases

September 30, 2022

On a hot summer day, most people avoid mosquitoes. But in June, a group of Notre Dame undergraduate and graduate student researchers instead headed toward the swirling swarms around Spicer Lake. These students worked with three Notre Dame professors to study the spread of mosquito-borne disease. The collaboration, funded in part by the Center for Social Concerns, more efficiently and effectively directed county resources to control the spread of mosquitoes and the diseases they carry. Grants like these from the center further research in all fields that contribute to the work of justice and promotion of the common good, in communities near and far. Center faculty and staff also support grant-funding projects by consulting on questions of community engagement. 

The group of professors working with the St. Joseph County Health Department forms the Vector Surveillance Program and includes Mary Ann McDowell, Ph.D., professor of biological studies, Jennifer Robichaud, M.S., teaching professor of biological studies, and Samuel Rund, Ph.D., a research assistant professor at the Center for Research Computing. The group collected hundreds of the insects to test as part of a larger effort to help the St. Joseph County Health Department track and manage the spread of viruses like West Nile and Eastern Equine Encephalitis. 

Managing the number and distribution of insects like mosquitoes is an ongoing challenge for public health units like the St. Joseph County Health Department. Viruses like West Nile can cause serious symptoms or even death among humans, but in their early stages can appear in ways similar to the common cold or flu. Doctors may not recognize a mosquito-borne disease until it is more advanced and difficult to treat. Fortunately, the diseases most commonly passed from mosquitoes to humans cannot be transmitted between humans. Each case of West Nile virus begins with a mosquito bite. Prevention through managing mosquito populations therefore becomes one of the most effective and important ways to limit the spread of these diseases. 

Tracking groups of mosquitoes, however, is a time-intensive process. The insects can lay eggs in a body of water as small as a soda can and are often most active at night, when they are especially difficult to see. Because of this, researchers commonly use traps to collect specimens to analyze, creating boxes or bags that attract and hold mosquitoes until they can be gathered and tested. Still, the sheer number of mosquitoes living in an area as large as St. Joseph County that has nearly 50 named bodies of water, according to the Indiana Department of Natural Resources, can be difficult to monitor. Even a small number of mosquitoes carrying an infectious virus can indicate the potential for a larger spread among both insect and human populations. Health departments around the country have struggled to identify, track, and effectively reduce pockets of infectious mosquitoes, lacking the human resources required to do so. 

The partnership with McDowell and her students has significantly changed this equation in and around South Bend, providing needed public health resources in a unique educational setting. Other Notre Dame faculty have previously worked with local health officials, but often only intermittently. In recent years, with the establishment of the “Vector Surveillance Program”, McDowell, Robichaud, and Rund have created more durable relationships, consistently collaborating on projects that advance both local health outcomes and research for high school, undergraduate, and graduate students. These joint efforts have been consistently positive, with McDowell describing local entomologists and other public health officials as “incredible to work with.” County leaders have frequently brainstormed with the Notre Dame group to identify new, sustainable projects that meet the needs and interests of everyone involved, including providing leadership opportunities for students. The efforts have paid off. Because of the work of the Vector Surveillance Program, St. Joseph County today has the most active mosquito monitoring program of any area in Indiana.

This effort also has implications for issues of justice because mosquito-borne disease is often highest among marginalized communities. Globally, this is seen in many countries where individuals and families in poverty are subsistence farmers that spend most of their time outdoors where they might encounter infectious mosquitoes. The trend is similar in the United States, however, where low-income individuals are similarly more likely to be employed in jobs that require outdoor work and are less likely to have air conditioned homes (resulting in more open windows), increasing their exposure to potentially infectious mosquitoes. Compounding this challenge is low-income individuals’ frequently more limited access to health care, raising the risk of serious consequences from an infection. Here the power of prevention shines most clearly. Tracking and reducing the number of infectious mosquitoes is an effective way to improve health outcomes for marginalized communities even if nothing else changes.