Flesh-eating bacteria have infected at least five men who were exposed to water in the Delaware Bay or who had eaten undercooked crabs from the bay since 2017. Researchers at Cooper University Health Care, where the men were treated, say the number of cases is increasing, though still relatively rare.
In an article being published Monday in the Annals of Internal Medicine, the researchers caution that climate change could be a factor in the uptick.
The cases should not cause alarm about eating local seafood or going in the bay, researchers and experts say. All victims of the flesh-eating bacteria had pre-existing conditions that made them more susceptible to infection.
One of the victims, a 64-year-old man who had eaten crabs, died. Four others survived but underwent extensive treatment including amputation, skin grafting, or skin removal.
“What is interesting is that in the eight years prior to 2017, Cooper only saw one case of Vibrio vulnificus,” Katherine Doktor, an infectious-disease specialist at Cooper, said in an email. “In 2017 we saw three cases, and in 2018 another two. So while the infection is still rare, it is being seen with more frequency in this region.”
Vibrio vulnificus is one of about a dozen species of Vibrio bacteria that can cause vibriosis illness, which can result in diarrhea and vomiting, according to the U.S. Centers for Disease Control and Prevention.
However, Vibrio vulnificus can cause more serious illness, including severe blistering skin lesions and life-threatening bloodstream infections. Infected patients can develop a condition called necrotizing fasciitis — commonly referred to as “flesh eating.”
The bacteria live mostly in southeastern U.S. coastal waters and are seen in higher concentrations between May and October, when water temperatures rise. Vibrio thrives in surface-water temperatures above 55 degrees.
But the Cooper report found rising water temperatures provide more-favorable conditions for Vibrio in areas that were once considered too cool, Doktor said.
Previously, cases involving Vibrio vulnificus had been mostly confined to the Chesapeake Bay and waters farther south, the Cooper team wrote. Traditionally, the waters in the more northern Delaware Bay have been slightly cooler. But the research team wrote, “Climate change has resulted in significant increases in sea surface temperatures in many regions of the United States over the past three decades.”
The result has been longer summers associated with an increase in bacteria, including species of Vibrio, in brackish waters — a mix of sea water and fresh water.
The team used water temperature data from the National Oceanic and Atmospheric Administration as a reference. Other published studies, the authors said, have also documented increased water temperatures and its impact on Vibrio. In fact, NOAA has also warned that climate change could increase Vibrio counts in shellfish.
“The purpose of the article is to create awareness on many levels — particularly among clinicians who may not have seen a patient with this rare infection,” Doktor said. “It is important for them to be aware that this bacteria is becoming more common in this region, although still very rare.”
She said anyone with cuts, sores, or broken skin who notices the appearance of infection after spending time in brackish water should seek medical attention. Quick intervention produces the best outcomes.
The paper reviewed only cases treated at Cooper. Some victims were first seen by local hospitals before being transferred to the Camden medical center.
Doktor said all the patients had known risk factors, such as liver disease, diabetes, or other immune-system compromises when they were exposed to water and/or uncooked crustaceans or shellfish harvested from the Delaware Bay, such as oysters or crabs.
For most healthy people, being in or around the water poses no increased risks, she said.
However, she added that, as a general rule, fresh seafood should always be properly cooked.
Indeed, the CDC cautions people eating raw oysters, in particular. Oysters feed by filtering water and the bacteria can become concentrated in their tissues.
Dave Bushek, an associate professor and director of the Haskin Shellfish Research Laboratory at Rutgers, said, “While the risks are real and can be severe for a small fraction of the population, basically those with other health issues such as liver problems, diabetes, etc., the vast majority of people have little risk.” Bushek was not involved with the Cooper team’s research.
Below is a summary of the Cooper cases: