How Climate Change Impact Is Changing Infectious Disease Patterns

This article first appeared in our sister brand, Managed Healthcare Executive.

Warmer weather and the sharp ups and downs of wetter conditions from floods and hurricanes and drier conditions from drought are changing where and when certain infectious diseases occur — and clinicians need to be on the lookout for them, says Peter Rabinowitz, MD, MPH, a professor of environmental and occupational health sciences and director of the University of Washington School of Public Health Center for One Health Research in Seattle. Rabinowitz was a speaker at 2 sessions on climate change year at the 2024 ID Week meeting in Los Angeles, California, held from October 16 -20, 2024.

Rabinowitz, who trained as a family physician, said it is essential for clinicians to know how climate change alters infectious diseases. As the climate becomes more volatile, diseases not typically seen in certain areas may start to occur and become common.

For example, warmer weather will mean an increase in some areas of mosquito-borne diseases, such as dengue fever, Zika, and chikungunya, Rabinowitz said in an interview with Infection Control Today’s sister brand, Managed Healthcare Executive (MHE).

Rabinowitz told MHE that wet conditions after flooding from hurricanes and other extreme weather events are likely to make leptospirosis more common. Leptospira bacteria cause leptospirosis in animals' urine, and flood waters can become contaminated with the urine of infected animals.

Droughts are another climate change-driven factor altering the who, where, and when of infectious diseases. They can change the range of ticks and, therefore, the risk of tick-borne disease, said Rabinowitz, who is also codirector of UW Alliance for Pandemic Preparedness.

He noted that extensive periods of dry weather can also mean the emergence of dust-borne diseases, such as Valley fever. Valley fever, also called coccidioidomycosis, is a lung infection caused by inhaling the spores from the Coccidioides fungus that lives in the soil in dry areas of the US.