Vibrio vulnificus (V. vulnificus) is a kind of warm water–loving bacteria that can cause gastroenteritis and necrotizing fasciitis. In the last few weeks, deaths due to vibriosis, the illness caused by the bacteria, have been reported in Connecticut, Florida, and New York. Cases are on the rise.
People can come into contact with V. vulnificus by swimming in salt or brackish water with an open wound. Eating oysters or certain fish exposed to Vibrio can also result in illness.
Certain patients may be more at risk, including men and people over the age of 40.
Within the last few weeks, reports of a rare, necrotizing fascitis–causing bacteria called Vibrio vulnificus (V. vulnificus) have surfaced, with health officials noting the deaths of two people in Connecticut, one in New York, and five in Florida. This is one of the many bacterial strains that eat flesh.
According to the Centers for Disease Control and Prevention (CDC), V. vulnificus are opportunistic bacteria that live in certain coastal waters and appear more often between May and October, when water temperatures are warmer.
Susan Donelan, MD, Medical Director of Healthcare Epidemiology at Renaissance School of Medicine at Stony Brook University in Stony Brook, NY, tells MDLinx, “V. vulnificus has certain intrinsic characteristics that distinguish it from other organisms in the Vibrio family; these characteristics are what facilitate, in some cases, extreme morbidity and mortality.”
The CDC says that vibriosis causes an estimated 80,000 illnesses annually in the US, with about 52,000 of those estimated to result from eating contaminated food. Vibrio parahaemolyticus is the most commonly reported species, causing an estimated 45,000 illnesses yearly in the US—and it could be on the rise”.
According to Nature, the number of V. vulnificus infections between 1988 and 2018 in the Eastern US increased eightfold—likely due to climate change. The researchers predicted that by 2041 to 2060, the bacteria may be seen moving northward into major population centers around New Jersey and southern New York state, with annual cases doubling. They also say that by 2081 to 2100, V. vulnificus infections may appear in every Eastern US state under medium-to-high future emissions and warming.
Many people come into contact with V. vulnificus by swimming in saltwater or brackish water— where fresh water and saltwater meet—with an open wound. The National Library of Medicine (NLM) says V. vulnificus enters the food chain by residing in the stomachs of shellfish (primarily oysters) as well as the intestines of fish. In fact, V. vulnificus makes up 95% of all seafood-related deaths in the US.
Patients concerned about the bacteria should be encouraged to learn how their food is prepared and stored. In Connecticut, where one V. vulnificus death has occurred and where oysters are an industry staple, there are laws around the storage and refrigeration of oysters. NBC reports that the state Bureau of Aquaculture doesn’t believe any of the infections are linked to Connecticut shellfish.
According to the NLM, V. vulnificus presents in three ways: primary septicemia, primary wound infection, and primary (and limited) gastroenteritis. After eating food contaminated by the bacteria, patients may experience watery diarrhea, fever, nausea, vomiting, and primary septicemia syndrome. About half of patients die from primary sepsis.
The CDC says that V. vulnificus can cause life-threatening wound infections that require intensive care and amputation. One in five people with vibriosis die, often within 24 to 48 hours after becoming sick. This species also leads to necrotizing fasciitis, in which the bacteria eat the flesh of an open wound. The overall mortality rate for patients with underlying hepatic disease is as high as 54%.
Some patients may only experience a gastrointestinal presentation, which occurs in 10 to 15% of cases. In a healthy patient, Dr. Donelan says, HCPs could see a mild case play out as “self-limited gastroenteritis, with diarrhea, nausea, vomiting, cramping, chills and perhaps a low-grade fever.” In this case, the risk is that patients might not seek care.
“If the organism transitions to the bloodstream from the gastrointestinal tract, it may cause septicemia—with weakness, low blood pressure, high fevers, blisters or bullae—and represents a true life-threatening illness,” Dr. Donelan says.
Male patients and those over the age of 40 tend to be diagnosed more frequently. However, Dr. Donelan says that certain patients are at even higher risk of vibriosis: “While serious infection can potentially result from exposure to V. vulnificus in normally healthy people, it is particularly worrisome for persons with underlying conditions, such as liver disease, poorly controlled diabetes, cancer, or immunocompromising conditions, or those who require medications [that] cause immunocompromisation,” she says.
“Therefore, it is advisable that at-risk persons choose to forego raw or undercooked shellfish or juices. Those with no compromising conditions may choose to do this as well,” she adds.
Open wounds—like small punctures, a new tattoo or body piercing, a diabetic foot ulcer, or a healing surgical incision—should be kept away from warm brackish or saltwater, as they provide entry to the bacteria, Dr. Donelan says. If this is unavoidable, HCPs should tell patients that any wounds should be thoroughly covered with a waterproof dressing.
Dr. Donelan says that if you suspect the bacteria has entered a wound, check the patient for fever, warmth, tenderness, redness (including streaking redness from the wound), blisters, bullae, or pain that is disproportionate to what is visible.