About Vibrio Infection

Key points

  • Vibrio are bacteria that naturally live in coastal waters.
  • About a dozen kinds of Vibrio can cause people to get an infection called vibriosis.
  • People can get vibriosis after swallowing Vibrio or getting it in a wound.
  • Vibrio infection can be serious. Know when to seek medical care.
A group of three-dimensional oblong-shaped Vibrio parahaemolyticus bacteria.


What are Vibrio?

Vibrio are bacteria that naturally live in certain coastal waters. They are found in higher numbers in May through October, when water temperatures are warmer.

Coastal waters include salt water and brackish water. Brackish water is a mixture of salt water and fresh water. It is often found where rivers meet the ocean.

What is vibriosis?

About a dozen species (kinds) of Vibrio can cause a human illness called vibriosis. The most common species causing human illness in the United States are

  • Vibrio parahaemolyticus
  • Vibrio vulnificus
  • Vibrio alginolyticus

Keep in mind‎

This site focuses on vibriosis. Other strains of Vibrio can cause a human illness called cholera.

How do people get vibriosis?

Most people get vibriosis by eating raw or undercooked shellfish, particularly oysters.

Some people get vibriosis after an open wound comes in contact with coastal waters.

How common is vibriosis?

CDC estimates that:

  • 80,000 cases of vibriosis happen each year in the United States.
  • 52,000 cases of vibriosis are the result of eating contaminated food.


Common signs and symptoms of Vibrio infection

  • Watery diarrhea
  • Stomach cramps
  • Nausea
  • Vomiting
  • Fever
  • Chills

Signs and symptoms of Vibrio bloodstream infection

  • Fever
  • Chills
  • Dangerously low blood pressure
  • Blistering skin lesions

Signs and symptoms of Vibrio wound infection

  • Fever
  • Redness
  • Pain
  • Swelling
  • Warmth
  • Discoloration (turning a color other than normal)
  • Discharge (leaking fluids)


Some Vibrio species, such as Vibrio vulnificus, can cause severe and life-threatening infections.

Some Vibrio infections lead to necrotizing fasciitis, a severe infection in which the flesh around an open wound dies. Some media reports call Vibrio vulnificus "flesh-eating bacteria." However, public health experts believe group A Streptococcus are the most common cause of necrotizing fasciitis in the United States.

Many people with Vibrio vulnificus infection can get seriously ill and need intensive care or limb amputation. About 1 in 5 people with this infection die, sometimes within a day or two of becoming ill.

When to seek emergency care‎

Immediately see your doctor or go to the emergency room if you have symptoms of a Vibrio bloodstream or wound infection. Do not wait.

People at risk

Anyone can get a Vibrio infection.

Some medical conditions and treatments can increase your risk for infection and severe complications. They include:

  • Having liver disease, cancer, diabetes, HIV, or thalassemia
  • Receiving immune-suppressing therapy for the treatment of disease
  • Taking medicine to decrease stomach acid levels
  • Having had recent stomach surgery

Some behaviors also can increase your risk of infection. These include:

  • Eating raw seafood, particularly oysters
  • Exposing an open wound to coastal waters
  • Exposing an open wound to raw seafood or its drippings

Diagnosis and testing

Infection is diagnosed when Vibrio are found in the wound, blood, or stool (poop) of an ill person.

If you have signs and symptoms of infection, be sure to tell your healthcare provider if

  • You recently ate raw or undercooked seafood, especially oysters
  • You have an open wound that might have come in contact with
    • Coastal water, including sale water or brackish water
    • Raw or undercooked seafood or its drippings


Antibiotics are not recommended to treat mild Vibrio infections. People with diarrhea or vomiting should drink plenty of liquids to prevent dehydration. Dehydration is not having enough fluids in the body.

Antibiotics can be used to treat severe or prolonged Vibrio infections.

Vibrio wound infection is treated with antibiotics and surgery to remove dead or infected tissue. Surgery might include amputation.