Office of Communicable Diseases

Information for Health Care Providers

Health Advisory for Clinicians

Date: 8/04/06

Vibrio vulnificus

The Rhode Island Department of Health has received a report of a confirmed case of Vibrio vulnificus ( V. vulnificus ) infection in a high-risk adult who presented at a local hospital with an infected leg wound and septicemia. The patient remains hospitalized and is improving. This is the first recorded case of V. vulnificus acquired by exposure to local seawater and/or shellfish consumption. Annually 50 cases are reported nationally from the Gulf Coast region with 30% to 50% mortality.

V. vulnificus is a bacterium in the same family as those that cause cholera. It normally lives in warm seawater and is part of a group of vibrios that are called "halophilic" because they require salt. It occurs naturally, rather than as a result of pollution. Oysters can accumulate the bacterium as they filter the water in which they live. The bacterium is frequently isolated from oysters and other shellfish in warm coastal waters during the summer months.

Water and shellfish testing from Conimicut Point in Warwick, where the exposure occurred has revealed low levels of V. vulnificus . Further testing is planned from the upper bay and other warm salt-water areas. Of particular concern are the areas of the upper bay (north of Greenwich Bay), inlets, shallow water areas and coastal ponds.

V. vulnificus can cause disease in those who eat raw or undercooked shellfish or have an open wound that is exposed to seawater. In otherwise heathy persons, V. vulnificus can cause mild illness such as vomiting, diarrhea, or localized wound infection. However, in high-risk individuals, V. vulnificus can invade the bloodstream via ingestion or wound infection, causing a severe and life-threatening illness characterized by fever, chills, decreased blood pressure (septic shock), blistering skin lesions, and often, death.

Persons at high risk of invasive disease include persons who are immunocompromised, especially those with chronic liver disease, AIDS; chronic alcohol abuse; liver, stomach, or blood disorders; cancer; diabetes; or kidney disease. There is no evidence for person-to-person transmission of V. vulnificus . V. vulnificus infection is an acute illness, and those who recover should not expect any long-term consequences.

If V. vulnificus is suspected, treatment should be initiated immediately because antibiotics improve survival. Culture of wound or hemorrhagic bullae is recommended, and all V. vulnificus isolates should be forwarded to the state public health laboratory. Blood cultures are recommended if the patient is febrile, has hemorrhagic bullae, or has any signs of sepsis. Aggressive attention should be given to the wound site, necrotic tissue should be debrided; severe cases may require fasciotomy or limb amputation .

Antibiotic Therapy:

•  Doxycycline (100 mg PO/IV twice a day for 7-14 days) and a third-generation cephalosporin (e.g.,ceftazidime 1-2 g IV/IM every eight hours) is generally recommended

•  single agent regimen with a fluoroquinolone such as levofloxacin, ciprofloxacin or gatifloxacin, has been reported to be at least as effective in an animal model as combination drug regimens with doxycycline and a cephalosporin.

•  Children, in whom doxycycline and fluoroquinolones are contraindicated, can be treated with trimethoprim-sulfamethoxazole plus an aminoglycoside.

Counsel your patients as follows:

•  Do not eat raw oysters or other raw shellfish.

•  Cook shellfish (oysters, clams, mussels) thoroughly

•  For shellfish in the shell, either a) boil until the shells open and continue boiling for 5 more minutes, or b) steam until the shells open and then continue cooking for 9 more minutes. Do not eat those shellfish that do not open during cooking. Boil shucked oysters at least 3 minutes, or fry them in oil at least 10 minutes at 375°F.

•  Avoid cross-contamination of cooked seafood and other foods with raw seafood and juices from raw seafood.

•  Eat shellfish promptly after cooking and refrigerate leftovers.

•  Avoid exposure of open wounds or broken skin to warm salt or brackish water, or to raw shellfish harvested from such waters.

•  Wear protective clothing (e.g., gloves) when handling raw shellfish.

Clinicians and microbiology laboratories should report cases of V. vulnificus directly to the Office of Communicable Diseases at (401) 222-2577.

For more information on Vibrio vulnificus:

Press release http://www.health.ri.gov/

http://www.cdc.gov/ncidod/dbmd/diseaseinfo/vibriovulnificus_g.htm