‘Flesh-eating’ bacteria spreading across East Coast could explode from climate change

NORWICH, United Kingdom — Concerning new research from the University of East Anglia reports that the continual warming of Earth’s climate may result in the proliferation of potentially fatal infections caused by bacteria found all along the East Coast of the United States. The “flesh-eating” bacteria called Vibrio vulnificus is known to grow in warm, shallow coastal waters and can infect humans via a cut or insect bite during contact with seawater.

These latest findings indicate that the number of Vibrio vulnificus infections along the East Coast of the U.S., a global hotspot for such infections, has increased considerably in recent years; from 10 to 80 annually over a 30-year period.

Additionally, each year new cases are being reported further north. During the late 1980s, most reports of the bacteria originated around the Gulf of Mexico and along the southern Atlantic coast with reports north of Georgia being rare. Today, cases are being seen as far north as Philadelphia.

Study authors predict that between 2041 and 2060, infections could even spread to major population centers around New York. Such a development, combined with a growing and increasingly elderly population who are more susceptible to infection, could lead to double the annual case numbers.

By 2081 to 2100, infections could be present in every single eastern U.S. state, according to medium-to-high future emissions and warming scenarios.

While the number of cases being reported in the country today isn’t all that large, anyone infected with V. vulnificus has a one-in-five chance of dying. It also happens to be the most expensive marine pathogen in the U.S. to treat. Peaking in the summer, the bacteria can spread quickly and severely damage a person’s flesh. Consequently, it is often referred to as a “flesh-eating” illness. Many survivors have had limbs amputated.

“The projected expansion of infections highlights the need for increased individual and public health awareness in the areas affected. This is crucial as prompt action when symptoms occur is necessary to prevent major health consequences,” says lead author of the study Elizabeth Archer, a postgraduate researcher in UEA’s School of Environmental Sciences, in a statement. “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.

“We show that by the end of the 21^st Century, V. vulnificus infections will extend further northwards but how far North will depend upon the degree of further warming and therefore on our future greenhouse gas emissions,” she continues. “If emissions are kept low, then cases may extend northwards only as far as Connecticut. If emissions are high, infections are predicted to occur in every U.S. state on the East Coast. By the end of the 21^st Century we predict that around 140-200 V. vulnificus infections may be reported each year.”

Movement of flesh-eating bacteria V. vulnificus an ‘indication of climate change’

Researchers say both individuals and health authorities could be warned in real time about particularly risky environmental conditions via either marine-based or Vibrio specific early warning systems. Meanwhile, active control measures can help too, such as greater awareness programs for at risk groups like the elderly or others with pre-existing health conditions, and coastal signage during high-risk periods.

“The observation that cases of V. vulnificus have expanded northwards along the East Coast of the U.S. is an indication of the effect that climate change is already having on human health and the coastline. Knowing where cases are likely to occur in future should help health services plan for the future,” comments co-author Prof Iain Lake from UEA.

This project is the first ever to map out how the locations of V. vulnificus cases have changed along the eastern coastline of the U.S. over time. It is also the first to analyze how climate change may influence the spread of infections in the future.

Data pertaining to where people caught V. vulnificus infections was obtained via the Centers for Disease Control and Prevention. This approach allowed researchers to map out how cases of Vibrio vulnificus have extended upwards north over 30 years between 1988-2018. Temperature information based on observations and computer-based climate models, meanwhile, were then used to predict where in the U.S. cases may occur by the end of the 21^st Century.

“This is a landmark paper which not only ties global climate change to disease but provides strong evidence for the environmental spread of this extremely deadly bacterial pathogen,” co-author Prof James Oliver from the University of North Carolina Charlotte concludes.

The study is published in Scientific Reports.