Rising temperatures due to climate change could significantly increase the intensity of enterovirus outbreaks, such as hand, foot and mouth disease and historically polio, by up to 40%, according to a study by researchers from Brown University, Princeton University and Johns Hopkins University.
Rising temperatures linked to climate change may significantly intensify enterovirus outbreaks, including hand, foot and mouth disease (HFMD) and historically polio, by up to 40%, according to a new study. This research, conducted by scientists at Brown University, Princeton University and Johns Hopkins University, was published in Nature Communications on July 31.
Researchers have long observed that enterovirus outbreaks, like those of HFMD, which causes fever and rash in children, typically spike during the summer. This pattern also held true for historical polio outbreaks in the United States. Despite these observations, the exact causes of these seasonal trends were not entirely understood until now.
“We find, even after controlling for other factors, that temperature appears to increase enterovirus transmission,” Rachel Baker, the John and Elizabeth Irving Family Assistant Professor of Climate and Health at Brown University, said in a news release. “Crucially, we see a similar sized effect for polio historically, and more recent enteroviruses serotypes that cause HFMD.”
The study’s co-author Saki Takahashi, assistant professor of epidemiology at Johns Hopkins University, expanded on this, noting the geographical variations in HFMD outbreaks.
“At higher latitudes, we see large outbreaks of HFMD every two or three years, but closer to the tropics we observe outbreaks twice a year – our results are able to capture these large scale patterns,” she said in the news release. Takahashi has previously researched the outbreak dynamics of enteroviruses in both China and Japan.
By employing an advanced epidemiological model, the researchers were able to determine that temperature combined with demographic factors, such as the timing of school semesters, could explain the biannual outbreaks of HFMD in southern China. In contrast, in more northern regions, temperature plays a more dominant role in influencing these outbreaks.
“What really matters is the seasonal range of climate, i.e., the maximum temperature and minimum temperature,” added co-author Wenchang Yang, associate research scholar of geosciences at Princeton University. “That might have implications for how we think about the future effects.”
Utilizing output from 14 different climate models, the team projected the impact of climate change on enterovirus outbreaks.
“A key finding is the impact of variability,” added Gabriel Vecchi, the Knox Taylor Professor of Geosciences and Director of the High Meadows Environmental Institute at Princeton University. “The impact of climate variability on disease dynamics is underexplored, and this study represents a clear advance in the needed exploration of this topic.”
The findings are concerning, revealing that climate change could potentially increase the peak size of enterovirus outbreaks by up to 40%, with significant variations depending on location and climate model. The study’s authors highlight the importance of enhanced surveillance and tracking mechanisms to monitor these susceptible dynamics.
“Serological surveys are vital for tracking susceptibility to enteroviruses and other pathogens,” Takahashi added.
By understanding the drivers behind these patterns and the looming threat of climate change, this research underscores the urgent need for public health preparedness to mitigate the future impact of enterovirus outbreaks.