|
Center for Food Safety & Applied Nutrition Foodborne Pathogenic Microorganisms and Natural Toxins Handbook |
|
|
1. Name of the Organism: Vibrio vulnificus |
This bacterium infects only humans and other primates. It has been isolated from a wide range of environmental sources, including water, sediment, plankton, and shellfish (oysters, clams, and crabs) and a variety of locations, including the Gulf of Mexico, the Atlantic Coast as far north as Cape Cod, and the entire U.S. west coast. Cases of illness have also been associated with brackish lakes in New Mexico and Oklahoma. |
| 2. Name of the Acute Disease: | This organism causes wound infections, gastroenteritis, or a syndrome known as "primary septicemia." |
| 3. Nature of the Disease: |
Wound infections result either from contaminating an open
wound with sea water harboring the organism, or by
lacerating part of the body on coral, fish, etc., followed
by contamination with the organism. The ingestion of V.
vulnificus by healthy individuals can result in
gastroenteritis. The "primary septicemia" form of the
disease follows consumption of raw seafood containing the
organism by individuals with underlying chronic disease,
particularly liver disease (see below). In these
individuals, the microorganism enters the blood stream,
resulting in
septic shock, rapidly followed by death in many
cases (about 50%). Over 70% of infected individuals have
distinctive bulbous skin lesions.
Infective dose -- The infective dose for gastrointestinal symptoms in healthy individuals is unknown but for predisposed persons, septicemia can presumably occur with doses of less than 100 total organisms. |
| 4. Diagnosis of Human Illness: | The culturing of the organism from wounds, diarrheic stools, or blood is diagnostic of this illness. |
| 5 .Associated Foods: | This organism has been isolated from oysters, clams, and crabs. Consumption of these products raw or recontaminated may result in illness. |
| 6. Relative Frequency of Disease: |
No major outbreaks of illness have been attributed to this
organism. Sporadic cases occur frequently, becoming more
prevalent during the warmer months.
In a survey of cases of V. vulnificus infections in Florida from 1981 to 1987, Klontz et al. (Annals of Internal Medicine 109:318-23;1988) reported that 38 cases of primary septicemia (ingestion), 17 wound infections, and 7 cases gastroenteritis were associated with the organism. Mortality from infection varied from 55% for primary septicemia cases, to 24% with wound infections, to no deaths associated with gastroenteritis. Raw oyster consumption was a common feature of primary septicemia and gastroenteritis, and liver disease was a feature of primary septicemia. |
| 7. The Usual Course of Disease and Some Complications: | In healthy individuals, gastroenteritis usually occurs within 16 hours of ingesting the organism. Ingestion of the organism by individuals with some type of chronic underlying disease [such as diabetes, cirrhosis, leukemia , lung carcinoma, acquired immune deficiency syndrome (AIDS), AIDS- related complex (ARC), or asthma requiring the use of steroids] may cause the "primary septicemia" form of illness. The mortality rate for individuals with this form of the disease is over 50%. |
| 8. Target Populations: | All individuals who consume foods contaminated with this organism are susceptible to gastroenteritis. Individuals with diabetes, cirrhosis, or leukemia, or those who take immunosuppressive drugs or steroids are particularly susceptible to primary septicemia. These individuals should be strongly advised not to consume raw or inadequately cooked seafood, as should AIDS/ARC patients. |
| 9. Analysis of Foods: |
Methods used to isolate this organism from foods are similar
to those used with diarrheic stools. To date, all food
isolates of this organism have been pathogenic in animal
models.
FDA has a genetic probe for V. vulnificus; its target is a cytotoxin gene which appears not to correlate with the organism's virulence. |
| 10. Selected Outbreaks: | Sporadic cases continue to occur all year, increasing in frequency during the warmer months. |
| MMWR 45(28):1996 Jul 26 reports on three incidents of V. vulnificus infection in Los Angeles, California. | |
| A multi-year summary of V. vulnificus incidents associated with the consumption of raw oysters is reported in MMWR 42(21):1993 Jun 04 | |
| For more information on recent outbreaks see the Morbidity and Mortality Weekly Reports from CDC. | |
| 11. Education | More information for consumers of raw shellfish is available in the FDA brochure If You Eat Raw Oysters, You Need to Know . . .. |
mow@cfsan.fda.gov
January 1992 with periodic updates
