By Ethan Covey
The effects of climate change will alter the epidemiology of infectious diseases, threatening to unleash new microbes and change the characteristics of human immunity, according to experts at Johns Hopkins.
The piece is one of four by Johns Hopkins University School of Medicine professors addressing how rising temperatures may threaten humanity (J Clin Invest [Epub Jan 6, 2020]. https://doi.org/10.1172/JCI135003).
“Given that microbes can adapt to higher temperatures, there is concern that global warming will select for microbes with higher heat tolerance that can defeat our endothermy defenses and bring new infectious diseases,” said Arturo Casadevall, MD, PhD, a professor of molecular microbiology and immunology, and infectious diseases, at the Johns Hopkins University School of Medicine and Bloomberg School of Public Health, in Baltimore. This, according to Dr. Casadevall, may result in “the specter of new infectious diseases.”
Dr. Casadevall hypothesized that global warming will lead many fungal species to adapt to higher temperatures, and some with pathogenic potential for humans will break through the thermal defensive barrier provided by endothermy. Similar arguments can be made for viruses, bacteria and parasites. For example, there are concerns about the near-simultaneous emergence of Candida auris on three continents, an occurrence that may be tied to global warming (mBio 2019;10[4]: pii: e01397-19. doi: 10.1128/mBio.01397-19).
To address this threat, Dr. Casadevall noted the need for enhanced surveillance for new diseases, research into nonhuman host–microbe interactions, continued development of antimicrobial therapeutics, and the development of threat matrices to identify potential threats.
While the challenges posed by climate change are of the utmost concern, Dr. Casadevall highlighted the work done in recent years to combat coronaviruses and Ebola. “The best insurance against future threats is continued investment in surveillance, epidemiology, antimicrobial therapeutics and basic research into mechanisms of microbial pathogenesis,” he said.
