Vibrio parahaemolyticus bacterium is in the same family as those that cause cholera. It lives in brackish saltwater and causes gastrointestinal illness in humans. About a dozen Vibrio species can cause human illness, known as vibriosis. The most common species causing human illness in the United States are Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio alginolyticus.
Vibrio naturally inhabits coastal waters in the United States and Canada and is present in higher concentrations between May and October when water temperatures are warmer.
You also can get an infection if an open wound comes into contact with raw or undercooked seafood, its juices, or its drippings or with saltwater or brackish water.
Eating raw seafood, particularly oysters, and exposing open wounds to salt water or brackish water can increase a person’s chance for getting vibriosis.
Anyone can get sick from vibriosis, but you may be more likely to get an infection or severe complications if you:
When ingested, Vibrio causes watery diarrhea often with abdominal cramping, nausea, vomiting, fever and chills.
Usually these symptoms occur within 24 hours of ingestion. Illness is usually self-limited and lasts 3 days.
Vibrio bacteria can also cause a skin infection when an open wound is exposed to salt water or brackish water. Brackish water is a mixture of fresh and salt water. It is often found where rivers meet the sea.
A clinician may suspect vibriosis if a patient has watery diarrhea and has recently eaten raw or undercooked seafood, especially oysters, or when a wound infection occurs after exposure to seawater. Infection is diagnosed when Vibrio bacteria are found in the stool, wound, or blood of a patient who has symptoms of vibriosis.
Treatment is not necessary in mild cases, but patients should drink plenty of liquids to replace fluids lost through diarrhea. Although there is no evidence that antibiotics decrease the severity or duration of illness, they are sometimes used in severe or prolonged illnesses.
Most people with a mild case of vibriosis recover after about 3 days with no lasting effects.
However, people with a Vibrio vulnificus infection can get seriously ill and need intensive care or limb amputation.
About 1 in 5 people with this type of infection die, sometimes within a day or two of becoming ill.
An estimated 4500 cases of Vibrio infection occur each year in the United States.
However, the number of cases reported to CDC is much lower because surveillance is complicated by underreporting.
To improve our ability to monitor trends, infections caused by V. parahaemolyticus and other Vibrio species became nationally notifiable in 2007. State health departments report cases to CDC, and these reports are summarized annually.
Vibrio bacteria naturally live in coastal waters and can concentrate inside shellfish and other seafood that live in these waters.
You can reduce your risk of vibriosis by following these tips:
If you are in a group more likely to get vibriosis:
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