Doctors at Cooper University Hospital in Camden, New Jersey, first noticed a curious rise in flesh-eating infections in 2017 and 2018. But in the eight years prior to that, the hospital hadn’t reported a single case of the infection, which is caused by Vibrio vulnificus — a bacterium contracted through eating raw seafood or entering marine environments with an open wound.
Now, a team of researchers has published a report in the Annals of Internal Medicine, arguing that the sudden appearance of the infection, which is generally found in warmer water off the coast of southeastern United States and in other parts of the world, can be linked to rising ocean temperatures.
In recent years, the world’s oceans have absorbed the majority of the excess heat trapped in the atmosphere by greenhouse gas emissions. As a result, they’ve warmed faster than the rest of the planet.
Last year, in particular, was the warmest year ever recorded in marine environments.
The Vibrio vulnificus thrives in warm waters and has likely been able to expand its historic range because of rising temperatures, the researchers argue.
“Because waters in our region have warmed over the past decade or so, they are now a more hospitable environment for Vibrio vulnificus,” Madeline King, a co-author of the report, told Global Citizen.
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Most people who contract Vibrio bacteria experience uncomfortable flu-like symptoms, and eventually expel the pathogen. But Vibrio vulnificus is an especially potent strain of the bacteria that enters the bloodstream and begins to eat body tissue, resulting in a mortality rate of 20%.
When the infection reaches the bloodstream, it can generally be killed with antibiotics, but not before it damages tissue that often has to be removed. Of the five people discussed in the case study, one person died, while another had to have his hands and feet amputated. The other three people had to have damaged tissue removed.
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Although the infection remains rare, the authors of the report urge people to avoid eating raw shellfish and going into the ocean with open cuts.
“Covered limbs would help reduce the risk of acquiring a skin infection when in waters where Vibrio vulnificus may live,” King said.
As climate change intensifies around the world, various health threats are becoming more common.
The extreme weather events unleashed by climate change make it more likely for food and water sources to become contaminated as floodwaters carry toxins onto farmlands and into groundwater supplies. Droughts are increasing the prevalence of dust storms and forest fires, making people vulnerable to lung diseases like asthma. And higher temperatures are increasing the likelihood of heat strokes, dehydration, and skin cancer.
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Warming global temperatures are also expanding the distance that mosquitoes carrying deadly viruses, such as malaria and zika, are traveling. By 2080, a billion additional people could be exposed to deadly mosquito-borne diseases.
King’s team hopes that this new research can help doctors to better diagnose patients who arrive with strange symptoms, and, more broadly, understand the growing risk of climate change-related illnesses.
“Climate change poses a risk specifically for Vibrio vulnificus because as sea temperatures rise in areas which were previously non-endemic for Vibrio vulnificus, we could see more of these bacteria in waters farther north than previously described,” King said.