Flesh-eating bacteria: What to know about Vibrio vulnificus, and how to avoid it

CNN
—

Following the flooding caused by Hurricane Ian, Lee County, Florida has experienced what the state Department of Health has described as an “abnormal increase” in cases of a rare bacterial infection.

Florida has reported 64 Vibrio vulnificus infections and 13 deaths this year as of Friday, according to the health department, up from 34 cases and 10 deaths last year. This is the first time the number of cases has surpassed 50 since 2008, when the state began keeping track.

Many of the cases were centered in Lee County, where residents were cleaning up after Category 4 Hurricane Ian made landfall in late September.

These infections are rare but serious. According to the US Centers for Disease Control and Prevention, Vibrio vulnificus causes an estimated 80,000 illnesses and 100 deaths in the United States each year.

Vibrio vulnificus lives naturally in warm, salty or brackish water. It comes from the same family as the bacteria that cause cholera.

Vibrio can be found in water bodies around the world. In the United States, it lives in the Gulf of Mexico and along some coastal waters on the east and west coasts. The bacteria multiply in the warmer months when sea temperatures are at their highest.

Infection can occur when someone comes into contact with water that contains high levels of the bacteria or eats contaminated seafood.

A mild case of vibriosis typically includes chills, fever, diarrhea, abdominal pain, and possibly vomiting. People usually get sick within the first day of exposure to the bacteria.

Skin wounds infected with Vibrio vulnificus typically develop blisters, abscesses, and ulcers.

Vibrio vulnificus is one of the bacteria that can cause a so-called flesh-eating infection. Necrotizing fasciitis eats away the skin, muscles, nerves, fat, and blood vessels around an infected wound.

In more severe cases, people can develop blood poisoning. This is more common in people with underlying health problems, particularly liver disease, Cancer, diabetes, HIV or other diseases that suppress the immune system.

Septicemia is when the bacterium enters the bloodstream and spreads. It can cause fever, chills, low blood pressure, or skin blisters.

This can lead to septic shock if blood pressure takes a dangerous drop. The bacteria release toxins into the bloodstream that can extremely slow blood flow and damage tissues and organs.

It can also cause sepsis, in which the body mounts a powerful immune response that shuts down important organs like the heart or kidneys. Or it can lead to acute respiratory distress syndrome, or ARDS, a condition in which oxygen from the lungs doesn’t get into the blood. This can lead to brain damage and permanent lung damage.

If the infection gets into the bloodstream, the consequences can be fatal.

Typically, wound infection has a mortality rate of around 25%, studies show. It’s much higher for people exposed to the bacteria from eating contaminated food.

Most Vibrio infections in the US generally do not come from an infected wound, but rather from eating raw or undercooked seafood such as oysters, particularly during the summer months.

The bacteria can live in the belly of fish, oysters and other shellfish. Humans can consume the bacteria or be exposed to it when preparing raw seafood.

Vibrio vulnificus infection is the leading cause of death associated with seafood consumption in the United States. Most of these cases involve primary septicemia or bacteria in the bloodstream.

For skin infections, a doctor will first take samples from the infected area to determine if Vibrio vulnificus is causing the problem.

They will drain and treat any abscesses the infected site, sometimes coating the wound with a topical antibiotic and skin protectant in addition to other antibiotics. If necrotizing fasciitis is present, they may need surgery or even amputation of the affected limb to prevent the spread of infection.

Doctors say it’s important to seek treatment quickly. Studies show that people who get medical help as soon as they notice an infection respond better to treatment and are less likely to die from their infections.

However, this particular bacterium has developed some antimicrobial resistance. Studies show that up to 50% of Vibrio vulnificus infections no longer respond to certain antibiotics.

The 28 cases of Vibrio infection associated with Hurricane Ian in Lee County followed exposure to flood waters, which carried high levels of the bacteria into people’s homes, according to the health department. Some may have been uncovered during cleanup after the storm.

Six deaths from Vibrio infection have been reported in Lee County.

While these infections are still rare, this isn’t the first time a hurricane has brought a small spike in cases. According to the US Centers for Disease Control and Prevention, there was a surge after Hurricane Katrina in 2005, when people were also exposed to Vibrio vulnificus in flood waters.

Scientists fear that infections will continue to increase with climate change. Warmer oceans create a more welcoming environment for the bacteria, increasing the frequency of hurricanes — and people’s exposure to flooding.

The only way to prevent Vibrio infection is to avoid exposure.

If you have a skin wound, even a new tattoo or piercing, doctors advise staying out of the ocean and avoiding brackish water, or at least covering the area with waterproof bandages.

If you are exposed to salt water, the CDC recommends that you wash your hands and cuts thoroughly with soap and water afterwards.

If you must enter the water, such as during a hurricane cleanup, wear clothing and footwear that will protect any cuts or wounds from flood water.

You can also reduce your risk of vibriosis by making sure your seafood is well cooked. Avoid raw or undercooked oysters or other shellfish, and wash your hands with soap and water after handling raw shellfish.

For cooked shellfish, eat only those that open during cooking. For shelled oysters, the CDC recommends boiling, broiling, or grilling them for at least three minutes, or baking them at 450 degrees for 10 minutes.