Texas health officials are warning the public about the increased risk of Vibrio infections naturally found in coastal water.

Vibrio vulnificus/CDC
Vibrio vulnificus/CDC

Most infections occur between May and October, when the warmer water temperatures in the Gulf of Mexico promote the growth of these bacteria.

People can become ill after eating raw or undercooked contaminated seafood, particularly oysters, or when a person has an open wound that is exposed to seawater. Illness due to eating raw or undercooked seafood usually includes gastrointestinal symptoms such as vomiting, diarrhea, abdominal pain, nausea, fever, and chills. These symptoms frequently occur within 24 hours of eating and last approximately three days. Wound infections can cause redness, swelling, large blisters on the skin, skin ulcers, and, in serious cases, may even lead to limb amputation or death. People with a weakened immune system, liver disease, diabetes, cancer, or other chronic diseases or who have decreased gastric acidity are at highest risk for severe illness.

People who develop a skin infection or gastrointestinal symptoms that may be due to Vibrio bacteria should contact their medical provider immediately. They should inform their medical provider if their skin has been in contact with brackish water or seawater, raw seafood, raw seafood juices, or if they ate raw or undercooked seafood before they became ill.

In 2017, 30 percent of Vibrio cases reported in Texas were due to water exposure and another 21 percent to shellfish consumption with the exposure unknown in the remaining cases. Most cases with water exposure had cuts, bites, scratches or other pre-existing wounds. The majority of cases with shellfish consumption had eaten raw oysters before becoming ill.

Over the five year period of 2011-2015, the average number of Vibrio vulnificus­ infections reported in Texas has been 21 cases per year (ranging from 15 to 35). Of the 35 cases reported in 2015, 77% reported contact with water, 11% reported consumption of shellfish, mainly raw oysters, and for 11%, an exposure type could not be determined. Infections also appear to be seasonal in nature, with most (91% in 2015) occurring between May and October.

Over the five year period of 2011-2015, the average number of Vibrio parahaemolyticus infections reported in Texas has been 21 cases per year (ranging from 16 to 29). Of the 22 cases reported in 2015, 45% reported consumption of shellfish, mainly raw oysters,  36% reported contact with water,  and for 18%, an exposure type could not be determined. Infections also appear to be seasonal in nature, with most (68% in 2015) occurring between May and October.

Over the five year period of 2011-2015, the average number of vibriosis, other or unspecified infections reported in Texas has been 39 cases per year (ranging from 33 to 45). The most commonly reported species in the vibriosis, other or unspecified category in 2015 were Vibrio cholera non-O1 (31%), Vibrio alginolyticus (27%), and Vibrio fluvialis (27%). As with all members of the family, most infections (69% in 2015) appear to be seasonal, and occur between May and October.

Cholera is rare in Texas. The last cholera case reported in Texas was in 2012 and was acquired while traveling to an endemic country.


Health officials recommend the following precautions to reduce the risk of infection:

  • People with pre-existing wounds, including cuts, scrapes, fresh tattoos, blisters, or bites, should avoid contact with seawater and any kind of raw seafood.
  • People with a weakened immune system should wear protective water shoes.
  • If a wound is exposed to seawater or raw seafood, thoroughly wash the wound with soap and water, and see a medical provider if the area begins to look infected.
  • Do not eat raw shellfish, especially oysters; cook seafood thoroughly.
  • Wear protective clothing like gloves when handling raw seafood.
  • Keep raw seafood separate from other food to avoid cross-contamination, immediately clean up raw seafood spills with hot, soapy water, and thoroughly wash hands, utensils and surfaces after preparing or handling raw seafood.