Spreading Infections of Flesh-Eating Bacteria Linked to Climate Change

The number of Vibrio vulnificus infections is on the rise and spreading northward in the U.S., a new study has found. The researchers have linked the increasing and spreading infections to climate change and predicted that the pathogen will spread further in the coming decades without efforts to curb emissions.

Vibrio vulnificus can be a life-threatening wound infection, according to the U.S. Centers for Disease Control and Prevention (CDC). Infections from pathogens in the Vibrio genus can occur from eating raw or undercooked seafood or through contact of an open wound with saltwater or brackish water. 

Lower salinity and warmer water contribute to spreading the pathogen. These conditions become more favorable to Vibrio vulnificus because of global warming, James Oliver, co-author of the study and a biology professor at the University of North Carolina, explained to Inside Climate News.

About 10% of Vibrio vulnificus infection cases require surgical tissue removal or limb amputation, the study reported, and up to 18% of infections are fatal. Fatalities can occur within 48 hours of infection.

The study, published in the journal Scientific Reports, found that Vibrio vulnificus infections in the eastern U.S. increased eightfold from 1988 to 2018, from around 10 infections per year to around 80 infections per year.

Not only did the rate of the infections increase, but the researchers also observed that the cases shifted northward during that timespan. Cases were typically not found in geographic locations north of Georgia, but by 2018, there were regularly reported cases as far north as Philadelphia, Pennsylvania.

The study authors predicted that infections could spread farther northward into densely populated New Jersey and New York by 2060, and cases could double from 2041 to 2060.

“Our projections indicate that climate change will have a major effect on V. vulnificus infection distribution and number in Eastern USA, likely due to warming coastal waters favoring presence of bacteria and elevated temperatures leading to more coastal recreation,” the study authors wrote.

Without actions to curb greenhouse gas emissions and global warming, the researchers said Vibrio vulnificus infections could be present in every state in the eastern U.S. by 2100. But if emissions are minimized, infections may spread only northward to Connecticut, according to Elizabeth Archer, lead author of the study and a postgraduate researcher at the University of East Anglia’s School of Environmental Sciences.

“Greenhouse gas emissions from human activity are changing our climate and the impacts may be especially acute on the world’s coastlines, which provide a major boundary between natural ecosystems and human populations and are an important source of human disease,” Archer said, as reported by EurekAlert!

The researchers noted that this information could help public health officials prepare for spreading Vibrio infections, including creating informational programs for at-risk groups and developing signs to place along coasts when environmental conditions allow for more pathogen spread.