Polio is back, monkey pox isn’t slowing down, COVID-19 is still around, and now there’s more not-so-good news on the infection front: More than 200 human diseases could get worse because of the change climate, according to a new study.
Researchers have known for a long time that climate change affects disease. Warmer temperatures can make regions newly hospitable to disease-carrying mosquitoes, while more frequent storm floods can carry bacteria in their water waves.
Most research, however, focused on only a handful of threats or diseases at a time. The new study, published in Nature Climate Change, created a comprehensive map of all the ways various climate hazards could interact with 375 documented human infectious diseases.
The authors reviewed more than 77,000 scientific articles on these diseases and climate hazards. They found that of those 375 diseases, 218 could be exacerbated by things like heat waves, sea level rise and wildfires.
The study found four main ways climate change exacerbates disease. First, problems arise when changes bring disease-carrying animals closer to people. For example, animal habitats are disrupted by things like wildfires that drive bats and rodents into new areas, increasing the likelihood that they will transmit diseases like Ebola to people. Other research shows that climate change makes viruses more likely to jump from animals to people, as happened with the coronavirus that causes COVID-19. This phenomenon also likely contributed to the 2016 Zika outbreaks.
People also come closer to animals that cause disease during weather-driven events. Diseases such as cholera and Lassa fever were linked to human movement after storms and floods. Third, climate hazards also give pathogens a boost, such as how populations of disease-carrying mosquitoes grow in warmer temperatures. Finally, climate changes make people less able to cope with disease. For example, large changes in temperature can weaken the human immune system, which could be the reason for flu outbreaks.
If you’re interested in digging deeper into exactly all the diseases affected, the study’s authors created an interactive graphic that connects each disease to the climate hazards that amplify it. So you can see, for example, how drought, fires and floods make health problems caused by sand mosquitoes, including fevers and skin parasites, more common. Happy (or not so happy) commuting!