Vibrio is a genus of bacteria that are commonly found in marine environments, particularly in warm coastal waters. Some species, like Vibrio cholerae, are known to cause diseases in humans, such as cholera, which can lead to severe diarrhea and dehydration. These bacteria thrive in saltwater and can be associated with seafood, especially raw or undercooked shellfish. In addition to Vibrio cholerae, other species like Vibrio parahaemolyticus and Vibrio vulnificus can also cause gastrointestinal illnesses and infections. People with weakened immune systems are at higher risk for severe infections from these bacteria. Proper cooking and handling of seafood can help prevent infections caused by Vibrio.