Extreme weather events, which are increasingly likely due to climate change, are not only directly harmful, but can also have some less obvious negative effects. New research from the University of Maryland finds that illness from salmonella may increase with higher temperatures and more rainfall.
The researchers looked at extreme weather events—unusually high temperatures and heavy rainfall—in the state of Maryland and compared them with the number of salmonella outbreaks. They used data from the Maryland Foodborne Diseases Active Surveillance Network, a project funded by the Centers for Disease Control that tracks confirmed cases of sickness.
They found that both more rain and higher heat are associated with more outbreaks of salmonella. For people living in coastal regions, the risk of getting sick was even higher.
The bacteria occurs naturally in the bodies of livestock, and can easily contaminate water, soil and crops, which leads to sickness in people. Each year, an estimated 1.2 million people will be sickened by salmonella, and its symptoms typically last for just a few days. However, about 23,000 cases per year result in hospitalization and 450 end in death.
One limitation of the study is that it only looks at a small geographical region, so it’s not certain that the findings will apply to other areas. However, warmer and wetter weather does create an ideal growing environment for many kinds of bacteria—including pathogens like salmonella.
“Given the other literature that backs this up, I think you will see more salmonella cases with temperature spikes and precipitation spikes,” said Kristi S. Shaw, a researcher at the University of Maryland School of Public Health and one of the study’s authors, in an interview with Climate Central.
The findings of this study have been published in the journal Environment International.