In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to vibrio may increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.

What is Vibrio?

Vibrio is a bacteria that lives in warm coastal seawater. There are many different kinds of Vibrio bacteria. Each kind can cause a different illness. Some Vibrio bacteria will cause only a mild stomachache and mild diarrhea. Other Vibrio bacteria can cause severe diarrhea, vomiting, fever, and wound infection that can be life threatening.

Cholera, a very severe form of diarrhea, is caused by two specific groups of Vibrio cholerae. These groups of Vibrio cholerae are not usually found in the United States, so the chance of someone in the United States getting cholera is very low.

How can I get a Vibrio infection?

There are two ways that people can be exposed to Vibrio. One way is by eating raw or undercooked shellfish (like oysters) that came from seawater where there is Vibrio bacteria. The other way is by exposing an open wound or sore to seawater that has Vibrio bacteria. Vibrio is usually not passed from person to person.

How can I protect myself from Vibrio Infection?

Seawater that takes over an area after a hurricane or flood may contain Vibrio bacteria. You should try to avoid exposing open wounds or sores to seawater or floodwater by wearing boots and other protective gear. Even a scrape in the skin can be an opening for the Vibrio bacteria to enter. If a wound is exposed to seawater or floodwater, wash the area with soap and clean water as soon as possible. After floodwaters have dried, the Vibrio bacteria can no longer survive so the risk of infection should not be a concern.

Since eating raw or undercooked seafood has been associated with vibrio infection, fully cooking seafood before eating it is a good way to prevent infection

Will Vibrio make me sick? How do I know if I have a Vibrio Infection?

If you eat raw or undercooked shellfish that contains Vibrio, you can get a stomachache and diarrhea. This type of infection is not usually dangerous. However, it is important that you drink plenty of liquids to help prevent dehydration. See a health care provider if it becomes severe or lasts a long time.

If a wound is infected with Vibrio, the area around the wound will become red and swollen. The bacteria from the wound can enter the blood and cause fevers, chills, and blisters. If this infection is not treated, it can turn into a serious infection. People usually get sick from Vibrio 1-3 days after eating contaminated shellfish or after exposing a wound to contaminated seawater. People who have liver disease or a weak immune system are much more likely to become seriously ill from a Vibrio infection. If you have symptoms, you should see your healthcare provider immediately.

How can my health care provider tell if I have a vibrio infection?

A health care provider can look for the Vibrio bacteria in a wound, blood, or stool. Mild stomach illness from Vibrio does not usually need to be treated, but a wound infection should be treated immediately with medicine prescribed by a health care provider.

Can a Vibrio infection during my pregnancy hurt my baby?

Vibrio infection during pregnancy has not been well studied, so it is not known if Vibrio can harm a developing baby. The symptoms of Vibrio infection (diarrhea and vomiting) can lead to dehydration which can be of concern. Antibiotics that kill Vibrio bacteria are used to treat Vibrio during pregnancy. If you have a Vibrio infection, remind your health care provider that you are pregnant, and your health care provider can prescribe the right medicine for you.

Do I have to stop breastfeeding if I have a Vibrio infection?

Breast milk may help protect babies from many kinds of bacteria. One study has suggested that breastfeeding helped to reduce the risk of cholera in the infant when the mother was sick herself. Therefore, it may not be necessary to stop breastfeeding if you have a Vibrio infection. If you are breastfeeding and think you have a Vibrio infection, you should talk to your healthcare provider.

What if the baby’s father has Vibrio?

In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at


  • Centers for Disease Control and Prevention. 2017. Vibrio Infection. [Accessed January 2018]. Available at URL:,
  • Holmgren, J, et al. 1983. Receptor-like glycocompounds in human milk that inhibit classical and El Tor Vibrio cholerae cell adherence (hemagglutination). Infect Immun 39:147-154.
  • Khan, AI, Chowdhury, F, Leung D, et al. 2015. Cholera in pregnancy: Clinical and immunological aspects. Internal J of Infect Dis. 39:20-4.
  • Qureshi K, A et al. 2006. Breast milk reduces the risk of illness in children of mothers with cholera: observations from an epidemic of cholera in Guinea-Bissau. Pediatr Infect Dis J 25:1163-1166.