The Florida Department of Health has reported eight cases of Vibrio vulnificus infection so far in 2015, including two fatalities. The deaths have been reported in Brevard and Marion counties, according to a health department update Thursday.

Florida map/National Atlas of the United States
Florida map/National Atlas of the United States

The eight cases have been reported from the following counties–Brevard (1), Broward (2), Duval (1), Marion (1), Pasco (1), Santa Rosa (1) and St. Lucie (1).

Vibrio vulnificus is a naturally occurring bacteria in warm, brackish seawater. Infections caused by V. vulnificus are rare.

According to the Todar’s Online Textbook of Bacteriology, V. vulnificus causes a disease with over a 50 percent mortality rate, and it causes 95 percent of all seafood-related deaths.

Vibrio vulnificus is an emerging pathogen of humans. It causes wound infections, gastroenteritis, or a syndrome known as primary septicemia. It was first recognized as an agent of disease in 1976.  The first documented case of disease caused by the bacterium was in 1979.

V. vulnificus causes disease in individuals who eat contaminated seafood (usually raw or undercooked oysters) or have an open wound that is exposed to seawater. Among healthy people, ingestion of V. vulnificus can cause vomiting, diarrhea, and abdominal pain.  Most V. vulnificus infections are acute and have no long-term consequences.

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In immunocompromised persons, particularly those with chronic liver disease, V. vulnificus can invade the bloodstream from either a wound or from the GI tract, causing a severe and life-threatening illness called primary septicemia, characterized by fever, chills, septic shock and death. Blistering skin lesions accompany the disease in about 70% of the cases. V. vulnificus bloodstream infections are fatal about 50% of the time.

These individuals are 80-200 times more likely to develop V. vulnificus primary septicemia than are healthy people. For this particular risk group, the infection carries one of the highest mortality rates of all bacterial infections.