CDC Urges Doctors to Suspect Deadly Bacteria in Wound Infections

Following a trio of fatal cases in the Northeast, the CDC is alerting healthcare professionals to suspect Vibrio vulnificus infection, which requires rapid treatment to reduce mortality.

CDC issued a Health Alert Network advisory urging clinicians to “consider V. vulnificus as a possible cause of infected wounds that were exposed to coastal waters” — especially if near the Gulf of Mexico or East Coast, and when sea surface temperatures are warmest.

Since July 1, there have been three deaths in the Northeast — two in Connecticut and one in New York — due to V. vulnificus, and North Carolina saw three deaths due to the bacteria during that time, CDC said.

While V. vulnificus has most commonly been reported in Gulf Coast states, scientists say climate change is expanding the bacteria’s distribution and increasing the number of people who may be at risk. Florida, for instance, has already had seven confirmed V. vulnificus-related deaths this year.

Wound infections due to the bacteria rose eight-fold from 1988 to 2018, according to a recent study in Nature. In addition, its northern case limit shifted northward by about 30 miles per year during that time, the study found.

“The northward V. vulnificus infection expansion stresses the need for increased individual and public health V. vulnificus awareness in these areas,” the authors wrote. “This is crucial as prompt action when symptoms occur is necessary to prevent major health outcomes.”

There are many species in the Vibrio genus — including V. cholerae, which causes cholera — and they thrive in salt and brackish water. These bacteria cause an estimated 80,000 illnesses in the U.S. each year, according to the CDC. Most people have diarrhea, and some might also have stomach cramping, nausea, vomiting, fever, and chills.

But V. vulnificus is particularly pathogenic, especially if it gets into an open wound. It can enter through the smallest of skin lesions — think piercings, tattoos, tiny cuts and scrapes — and infections can very rapidly turn necrotic, according to the Nature paper. Wound infection mortality rates are as high as 18% and fatalities have occurred as soon as 48 hours after exposure.

The CDC said there are currently about 150 to 200 V. vulnificus infections each year, and these are primarily skin infections; in about 10% of cases, this species can infect people if they eat raw or undercooked shellfish. In addition to exposing an open wound to salt or brackish water, skin infections can occur by handling raw or undercooked shellfish.

These wound infections have a short incubation period and are characterized by necrotizing skin and soft tissue infection, with or without hemorrhagic bullae, CDC said. Many people require intensive care or surgical tissue removal.

CDC noted that “prompt treatment is crucial to reduce mortality from severe V. vulnificus infection.” Early antibiotic therapy and early surgical intervention improve survival, CDC said: “Do not wait for consultation with an infectious disease specialist or laboratory confirmation of V. vulnificus infection to initiate treatment.”

Clinicians can treat the infection with a combination of doxycycline 100 mg orally or IV twice a day for 7 to 14 days, along with a third-generation cephalosporin such as ceftazidime 1-2 g IV or intramuscularly every 8 hours.

Alternate treatment regimens include a third-generation cephalosporin with a fluoroquinolone (such as 500 mg ciprofloxacin orally twice a day), or a fluoroquinolone alone.

Children can be treated with a combination regimen of a third-generation cephalosporin plus doxycycline or ciprofloxacin, or with an alternative regimen of trimethoprim-sulfamethoxazole plus an aminoglycoside.

CDC also urged the public to stay out of salt and brackish water if you have an open wound or cut, and if you get cut while in the water, get out immediately and wash it thoroughly with soap and clean running water. Seek medical attention right away if it becomes infected.

In addition to its expanding geographic range, more frequent and stronger storms associated with climate change may boost V. vulnificus infection rates in the U.S., experts warn.

A significant storm surge during Hurricane Ian in Florida, for instance, brought an astonishing number of Vibrio and V. vulnificus infections, according to a recent publication in Morbidity & Mortality Weekly Report.

A total of 38 culture-confirmed cases were attributed to the storm, and the majority of these (76%) were due to V. vulnificus. Most cases (n=33) were skin infections associated with exposure to the storm surge or flood waters.

Only two cases didn’t require hospitalization. Those who were hospitalized stayed for a median of 10 days, with eight needing skin grafts and three requiring lower extremity amputation.

Among the 11 deaths, nine occurred in people who were infected with V. vulnificus; one death was due to V. cholerae, and another was due to an unknown Vibrio species.

The case fatality rate was nearly 29%, but the authors noted this may have to do with the median patient age of 80.

By comparison, during Hurricane Katrina in New Orleans in 2005 — which had the highest storm surge in U.S. history — there were just 22 vibriosis cases.