The CDC has issued a HAN Report about severe Vibrio vulnificus infections that are associated with warming coastal waters. The report is to notify healthcare providers, laboratories, and public health departments about recent reports of fatal Vibrio vulnificus infections from food and infected wounds, and to warn the public about this issue.
Vibrio causes about 80,000 human illnesses every year in the United States. About a dozen species of this pathogen are pathogenic to humans. Vibrio parahaemolyticus causes the most infections, follow by Vibrio alginolyticus. About 150 to 200 Vibrio vulnificus infections are reported to the CDC every year. About 20% of these infections are fatal.
Vibrio species live in coastal waters, including salt water and brackish water, which is a mixture of salt and fresh waters. Most people contract this infection by eating raw or undercooked shellfish, especially oysters. Some people can get infected if an open wound comes into contact with raw or undercooked seafood or salt water and brackish water.
These wounds can include recent tattoos and piercings, surgeries, and cuts and scrapes. Extreme weather events, including floods, hurricanes, and storm surges, can force coastal waters inland, putting people who are exposed to these waters at increased risk for Vibrio wound infections. This happened after Hurricane Ian.
Most Vibrio vulnificus infections are wound infections. Only about 10% of these infections are linked to the consumption of raw or undercooked seafood.
Vibrio species thrive in warmer waters, especially during the summer months. Most infections are reported in Gulf Coast states, but these infections in the eastern United States increased eightfold from 1988 to 2018.
During July and August 2023, the U.S. has experienced above average coastal sea surface temperatures and widespread heat waves, which has increased the Vibrio population. The states of Connecticut, New York, and North Carolina have reported severe Vibrio vulnificus infections and fatal infections.
People who are at increased risk for severe Vibrio vulnificus infections should be cautious when going into coastal waters. Stay out of salt water and brackish water if you have a wound or cut. And that group should avoid eating raw or undercooked shellfish. Everyone should wash their hands with soap and water after handling raw shellfish.
