INHS research informs control and management strategies for infectious diseases that can impact humans, livestock, and wildlife. INHS scientists assess the distribution and abundance of disease-causing pathogens and their vectors, genetic and environmental factors underlying disease susceptibility, and the impact these infectious diseases have on populations.

Amphibian & reptile diseases

Phillips Herpetology Lab scientists and other INHS researchers study diseases that impact the health and future wellbeing of amphibian and reptile species in Illinois and beyond. Research includes assessing the prevalence and impact of:

• chytridiomycosis, a chytrid fungus, on North American amphibians;
• ophidiomycosis, an emerging infectious disease caused by the fungus Ophidiomyces ophiodiicola, on snakes; and
• infectious diseases (e.g., ranavirus, herpesvirus, and mycoplasma) on eastern box turtles.

Mammal diseases

Chronic wasting disease

Epidemiologists in the INHS Wildlife Veterinary Epidemiology Lab led by Nohra Mateus-Pinilla study how chronic wasting disease (CWD), a slow, deadly, incurable neurological disease, spreads among deer.

The lab has collaborated with the Illinois Department of Natural Resources wildlife biologists since 2002 to help support the surveillance, management, and health protection of wild deer in Illinois. Mateus-Pinilla measures the cases of CWD in the deer herd, studies changes in the number of new cases during a specific period, and analyzes factors contributing to disease spread. In addition, recent studies have focused on the geographic distribution of CWD among free-ranging white-tailed deer populations and genetic expressions that may influence the predisposition of deer to CWD infection.

The CWD surveillance program helps inform the public about CWD-infected areas. Mateus-Pinilla has collaborated with landowners and hunters to evaluate changes in disease and factors that may contribute to the effectiveness of the state’s strategy in maintaining the low prevalence of CWD in the herd. Early detection of CWD helps inform management decisions to decrease disease spread and protect the health of the deer herd.

CWD has been found in Illinois white-tailed deer populations, presenting signs of severe weight loss, stumbling, and other neurological manifestations of the disease that interfere with eating, drinking, and orientation. While the disease is fatal to animals, there have been no reported cases of CWD infections in humans.

Researchers with the INHS Human Dimensions Research Program studied hunters’ and the nonhunting public’s perceived risk of being exposed to CWD through surveys sent eight years apart to ascertain how these risks may influence hunter behavior, such as quitting hunting or not eating venison. Results showed that perceived risks associated with CWD declined over eight years as the disease was no longer new nor a focus of media attention. Over time, hunters also tended to believe they can identify CWD-positive deer and take precautions. These types of studies inform management decisions and highlight societal consequences of wildlife diseases.

Epizootic hemorrhagic disease

Epizootic hemorrhagic disease (EHD) is a severe vector-borne viral disease that affects hooved animals, especially white-tailed deer. The virus (EHDV) is transmitted by biting midges, also known as no-see-ums or punkies. Researchers in the Wildlife Veterinary Epidemiology Lab investigate EHD outbreaks in Illinois and the receptors involved in the response of white-tailed deer to EHDV. The gene expression of this receptor may have a beneficial impact on the ability of deer to respond to EHD.

Toxoplasmosis

Wildlife Veterinary Epidemiology Lab scientists study how toxoplasmosis—an infection caused by a protozoan parasite that is carried and spread by wild and domestic cats—is affecting wildlife. They use a combination of live trapping, scent stations, and motion camera data to determine the distribution of feral, free-roaming, and domestic cats as well as medium-sized mammals around rural areas in close proximity to urban developments or buildings. These data will shed light on the relationship between cat occurrence and wildlife’s risk of contracting toxoplasmosis.

Read more about INHS mammal research.

Mosquito-borne diseases

Mosquitoes can be vectors for pathogens that infect both people and animals, such as Zika virus and West Nile virus. INHS Medical Entomology Lab scientists conduct statewide monitoring and surveillance of mosquito vectors. Using applied field and lab research, the research team generates ecological, genetic, behavioral, and epidemiological data that can guide infection prevention measures in Illinois and more effectively detect, prevent, and control mosquito-borne diseases.

Recent work has focused on detecting the distribution and abundance of the Asian tiger mosquito throughout Illinois; this mosquito can transmit exotic diseases like chikungunya and dengue fever as well as local viruses such as La Crosse virus. Since 2020 the lab has been conducting statewide surveillance of mosquitoes in collaboration with the Illinois Department of Public Health (IDPH). This includes identifying every mosquito by species and testing them for West Nile virus, La Crosse virus, Jamestown Canyon virus, and Eastern Equine Encephalitis virus, as well as others. This work will lead to a major update to our knowledge of statewide presence and abundance of mosquito species diversity in the state.

The research team is also conducting studies on:

• insecticide resistance in Illinois mosquito populations and the genetic mechanisms behind it;
• mosquito behavior and ecology, physiology, and immunology in the lab to better understand how resources in the landscape and climate change can affect vector-borne pathogen transmission;
• the efficacy of different surveillance methods for vectors of concern and the use of novel traps and bait stations as a control method;
• the impact of vegetation on West Nile virus vector abundance, behavior, and infection;
• effects of climate change on mosquito abundance, physiology, and spread; and
• mathematical models to optimize integrated control responses.

Tick-borne diseases

Ticks harbor and transmit numerous pathogens that can make people sick, including the agents of anaplasmosis, babesiosis, ehrlichiosis, Heartland virus, Lyme disease, Rickettsia parkeri-rickettsiosis, Rocky Mountain Spotted Fever, and tularemia. Alpha-gal Syndrome (also known as the “mammal meat allergy”) is an emerging tick-associated disease of concern in Illinois that can cause allergic reactions to mammal meat and mammal byproducts.

Active tick surveillance

The INHS Medical Entomology Lab launched Illinois’ tick surveillance program in 2019, with support from the IDPH. INHS scientists actively collect ticks at selected sites around the state via dragging and traps per Centers for Disease Control (CDC) criteria and conduct special investigations after human tick-borne diseases are reported.

The program has already dramatically improved understanding of the geographic distribution of known ticks and tick-borne diseases in Illinois and has documented the presence of new disease-carrying ticks in Illinois. An online interactive map makes it easy for all Illinoisans to access the tick surveillance data and find out what ticks have been found in their area.

Medical Entomology Lab scientists also train staff from forest preserve and park districts, county health departments, and mosquito abatement districts to conduct tick surveillance, provide them with materials, and receive ticks from them for identification and testing.

Passive tick surveillance

Illinois Tick Inventory Collaboration Network (I-TICK) scientists identify ticks encountered and submitted by Illinoisans whose work or leisure takes them outdoors. The program seeks to better understand where and when ticks come in contact with people, pets, and livestock, and also examine what human activities affect the risk of finding a tick. I-TICK is a collaborative effort between the INHS Wildlife Veterinary Epidemiology Lab and the University of Illinois College of Veterinary Medicine.

The INHS Medical Entomology Lab also offers a free tick identification service for Illinois residents and identifies ticks for health care and public health professionals who submit requests using the IDPH arthropod diagnostics form.