Key Takeaways

This summer saw the global spread of monkeypox, there-emergence of polio, and an outbreak ofhepatitisin young children—all against the backdrop of the ongoing COVID-19 pandemic.

A Report Signals “Code Red” on Climate Change’s Impact on Human Health

“Fifty-eight percent is a terrifying number,” saidTristan McKenzie, PhD, a coauthor of the study and a postdoctoral researcher at the University of Gothenburg, Sweden. “That is way above what we thought we would find when we started this study.”

Shifts in wildlife habitats due to rising temperatures are a major contributor to the spread of disease.

Rising temperatures pave the way for mosquitos, ticks, and fleas to move further north, putting them in proximity to more people. These insects can carry and spread vector-borne illnesses—they were the prolific pathway for disease transmission and were responsible for over 100 diseases in the study’s database, McKenzie said.

The global prevalence ofLyme disease, for example, has almost doubled since 2010, according to another study published inBMJ Global Health.The authors also pointed to longer summers, warmer winters, and changes in precipitation as factors in expanding the global tick population and allowing a greater spread of the disease.

Warming has allowed infectious bacteria to thrive in oceans, especially when flooding and hurricanes brings those waters closer to people. Droughts can have the same effect, pushing mosquitos, ticks, and livestock toward remaining water and food sources and accelerating outbreaks.

While the study documented the past impact of climate hazards on disease, the outlook for the future looks similar if the rate of warming is not slowed.

Doctors Call For More Training to Respond to Climate Change

A study published inNaturein April modeled potential future viral hotspots, finding that climate change increases opportunities forzoonotic spillover—when a disease jumps from wildlife to humans.

Bats were found to be the biggest risk in facilitating future outbreaks, and such spillover was suspected to be how the COVID-19 virus originated. Because bats can fly such long distances, the researchers found, their potential to expand their habitable range is far larger than other mammals, putting them in contact with more humans.

Climate hazards don’t just stop at aggravating vector-borne diseases. Floods and storms result in excess wastewater that creates a breeding ground for foodborne illnesses as well.

Climate Change Is Driving Longer, More Severe Pollen Seasons, Study Finds

Rising temperatures that defrost glaciers can also release pathogens that were frozen back into society. For example, a 2016 anthrax outbreak in the arctic circle was later found to have emerged from a bacterial strain previously frozen.Heat waves also breed high-temperature resistance in viruses, allowing them to survive in humans even when our immune systems fight back with fever.

“As a global community, we really need to work together on reducing greenhouse gas emissions. COVID was hard enough,” McKenzie said. “But the threat that we’re facing from climate changes is significantly greater.”

How Extreme Heat Can Worsen Mental Health

What This Means For YouRising temperatures and climate disasters have created the perfect breeding ground for bacteria and disease-carrying species. If we don’t take drastic measures to reduce greenhouse gas emissions, we might see more aggravated infectious diseases in the near future.

What This Means For You

Rising temperatures and climate disasters have created the perfect breeding ground for bacteria and disease-carrying species. If we don’t take drastic measures to reduce greenhouse gas emissions, we might see more aggravated infectious diseases in the near future.

4 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Dong Y, Zhou G, Cao W, et al.Global seroprevalence and sociodemographic characteristics ofBorrelia burgdorferi sensu latoin human populations: a systematic review and meta-analysis.BMJ Glob Health. 2022;7(6):e007744. doi:10.1136/bmjgh-2021-007744

Carlson CJ, Albery GF, Merow C, et al.Climate change increases cross-species viral transmission risk.Nature. 2022;607(7919):555-562. doi:10.1038/s41586-022-04788-w

Gross M.Permafrost thaw releases problems.Curr Biol. 2019;29(2):R39-R41. doi:10.1016/j.cub.2018.12.045

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