“We were astounded by the shear breadth of impacts that extreme weather events have on skin disease,” says Eva Rawlings Parker, a physician at the Department of Dermatology at Vanderbilt University Medical Center in the United States who was the lead author of the study.

Flooding, for instance, can cause not only severe wounds but also bacterial and fungal infections of the skin. “Contact dermatitis is another common consequence of flooding since flood water is often contaminated with pesticides, sewage, fertilizers, and chemicals,” the scientists note.

Exposure to wildfire smoke, meanwhile, “can trigger atopic dermatitis (eczema) in adults with no prior diagnosis, and it can trigger or exacerbate acne,” they say.

The skin plays a critical role in regulating body temperature, but prolonged heatwaves can severely compromise this ability, leading to heat stroke and death.

“Many chronic inflammatory dermatoses are exacerbated by heat as well. Infectious diseases can be seasonal, with heat and humidity increasing the risk of common cutaneous infections caused by bacterial, fungal, and viral pathogens,” the scientists explain.

Extreme heat events can have other effects such as forcing people without air-conditioning to spend more time outdoors where they can become more explosed to air pollution, UV radiation, and disease-carrying insects.

Especially at risk of weather-related skin conditions are children, pregnant women, older people, people with compromised immunity and low-income people, the scientists say.

“Extreme heat is a frontline occupational hazard for manual laborers and migrant workers. Extreme weather events contribute to large-scale migration,” the researchers write.

“Of particular concern is the spread of communicable and infectious diseases and vector-borne viruses. People experiencing homelessness are plagued by higher rates of highly morbid, climate-sensitive skin diseases,” they explain.

The findings are concerning as heatwaves and flood are becoming increasingly common worldwide.

“This year has been marked by historic and deadly heatwaves in North America, Europe, and Asia; devastating flooding in the United States, Pakistan, and Australia; drought and famine in Somalia and Madagascar; and wildfires in the Western US, Russia, Argentina, and throughout Europe,” Dr. Parker observes.

“Clinicians, policymakers, environmental advocates and researchers across the globe should be acutely aware of the current and future disruptions that climate change and extreme weather events pose to human health,” she stresses.