Several other members of the Vibrio family and related families are capable of causing a range of infections, with those most commonly being due to non-O1/non-O139 Vibrio cholera, Vibrio alginolyticus, Vibrio mimicus and Vibrio fluvialis. Like their relatives, these bacteria exist naturally in marine and estuarine environments throughout the world, including the warm coastal waters and some inland brackish lakes of the United States and Canada. Many of these bacteria are also capable of infecting marine fish and shellfish from warmer waters.
The less common members of the Vibrio family are also capable of causing the same kinds of illness as those seen for their relatives. These include wound infections, gastrointestinal illness, ear infections and septicemia.
- Most non-O1/non-O139 Vibrio cholerae infections involve less severe gastrointestinal illness, although a minority possess the cholera toxin and can cause cholera-like disease. Fewer cases of wound infections can occur, as well as primary septicemia in susceptible individuals with weakened immune systems.
- Wound and ear infections account for the majority of illness associated with Vibrio alginolyticus, although a small number of cases are also attributed to gastroenteritis.
- Vibrio mimicus is mainly responsible for causing cases of acute gastrointestinal illness. To a much lesser extent, the bacterium is also capable of causing ear infections.
- The bacterium Vibrio fluvialis is mainly associated with gastrointestinal illness and primary septicemia in susceptible individuals.
- Illness associated with wound and soft tissue infections arise after the exposure of a new or pre-existing wound to warm marine, estuarine or brackish water.
- Infections also commonly occur after individuals have lacerated themselves on coral, rocks or while fishing, harvesting, processing and handling fresh seafood and their drippings.
- These infections arise after swimming, diving, wading or participating in water activities that result in the exposure of the head to warm marine, estuarine or brackish water.
- Cases of gastroenteritis can occur after the consumption of infected/contaminated raw and improperly cooked, or cooked and then re-contaminated fish and shellfish (especially oysters).
- A higher risk of transmission has been linked to the warmer months of the year.
Bloodstream infections or primary septicemia:
These severe infections can occur after the ingestion of infected fish or seafood, primarily oysters, clams and crabs in certain individuals.
- These individuals include those who have weakened immune systems, liver conditions/disease and iron-related disorders (such as hemochromatosis), and are at an elevated risk of developing severe infection.
The incubation between exposure and illness onset is much less defined in other members of the Vibrio family and can range from hours to days.
Wound infection symptoms include:
- Blistering and ulceration
- Swelling and reddening
- Fluid build-up
- Sepsis and shock
Symptoms associated with ear infections include:
- Pain and aching around the affected ear and head
Gastrointestinal symptoms include:
- Abdominal pain
Symptoms of severe bloodstream infection in susceptible individuals can occur rapidly after ingestion and include:
- Sudden chills and fever
- Decreased blood pressure
- Skin lesions on the limbs and trunk of the body
The risks associated with the illnesses caused by less common members of the Vibrio family are the same for their more prevalent relatives. The greatest risks of acquiring infection are associated with:
- The consumption of raw, undercooked or contaminated cooked seafood, especially oysters.
- The exposure of a new or pre-existing wound to marine, estuarine and brackish waters.
- Swimming, diving, wading or participating in water activities that result in the exposure of the head to warm marine, estuarine or brackish waters.
General recommendations for avoiding gastrointestinal illness and severe infection in susceptible individuals:
- Implement refrigeration of seafood from harvesting/purchase to consumption.
- Avoid the consumption of raw seafood, especially oysters, if:
- They have come from coastal waters during the warmer months of the year
- You have a weakened immune system, liver disease/condition or an iron-related disorder
- When preparing oysters, mussels or other molluscan shellfish –
- Before cooking, discard any opened shells
- Boil, broil or fry (at 375°F) for at least 3-5 minutes
- Bake at 450°F for 10 minutes
- As a rule – discard any unopened shells after cooking.
- Only eat seafood or shellfish that is thoroughly cooked until steaming hot.
- Eat shellfish immediately after cooking and refrigerate leftovers.
- Avoid cross contaminating raw juices from seafood with other foods, and immediately cleanup any spills with hot water and soap and clean rinsing water.
- Keep raw seafood separate from other food.
- Thoroughly wash hands, utensils and surfaces after preparing or handling raw seafood.
General recommendations for avoiding wound and ear infections:
- Do not handle raw seafood of any kind if you have a pre-existing wound.
- Wear protective clothing (ie. Gloves) when handling raw seafood.
- Avoid marine, estuarine or brackish water if you have a pre-existing wound.
- If you sustain a wound or injury while exposed to salty seawater or while handling seafood, thoroughly clean and disinfect the area immediately and seek medical attention if the area becomes inflamed.
- Do not submerge the head in warm marine, estuarine or brackish waters.
Recent Texas Trends
Cases of illness associated with less common members of the Vibrio family range in number over the last decade from 28 to 36. As with all members of the family, most infections appear to be seasonal, and occur between May and October.