Vibrio vulnificus is a gram-negative bacillus that affects only humans and other primates. Besides V vulnificus, the genus Vibrio contains more than 100 bacterial species; about 12 Vibrio species are linked to human infections,[1] including the organism that causes cholera (ie, Vibrio cholerae). (See Vibrio Infections.) The first documented case of disease caused by V vulnificus was in 1979.
V vulnificus is usually found in warm, shallow coastal salt water in temperate climates throughout most of the world. It is present in the Gulf of Mexico, along most of the East Coast of the United States, and along all of the West Coast of the United States. V vulnificus can be found in water, in sediment, in plankton, and in shellfish (eg, oysters, clams, and crabs).
In addition, brackish, fast-warming waters in the Baltic Sea region can facilitate proliferation of Vibrio species, including V vulnificus.[1] Global climate alterations may elevate water temperatures and increase the incidence of V vulnificus infections.[2] Identifying and forecasting environmental factors that conduce to the development of V vulnificus infections may be assisted by the use of machine learning.[3]
V vulnificus can survive in seawater and can produce wound infections, a potentially serious problem among Asian tsunami survivors,[4] as well as potentially fatal necrotizing fasciitis in them and in individuals with liver cirrhosis.[5] (See the image below.) This halophilic bacterium can also cause serious gastroenteritis after ingestion of raw seafood.[6] Genome sequencing has been performed.[7]
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Vibrio infections. Early bullous lesions appear over dorsum of foot of patient with cirrhosis.
V vulnificus infects the body in either of the following two ways:
Ingestion of contaminated seafood (eg, raw oysters)
Exposure of an open wound to contaminated seawater
Healthy individuals typically experience vomiting, diarrhea, and abdominal pain within 16 hours of ingestion. Many patients develop distinctive bullous skin lesions. (See Presentation.) In immunocompromised individuals, particularly those with chronic liver disease (especially cirrhosis), immunosuppression, end-stage renal disease, and hematopoietic disorders, V vulnificus can cause life-threatening septic shock and blistering skin lesions. Those who are immunocompromised have a much higher risk of contracting V vulnificus infection and dying of overwhelming sepsis.[2]
The relatively low incidence of the disease suggests that not all strains of V vulnificus may be equally virulent. Data are consistent with the existence of two genotypes of the organism, with the C type being a strong indicator of potential virulence.[8] The biotype 3 group of V vulnificus may have emerged in Israel as a consequence of genome hybridization of two bacterial populations. The emergence of this clonal subgroup suggests that the fish aquaculture environment, and possibly human-made ecologic niches as a whole, may be a source of new pathogenic strains.[9]
V vulnificus can be found in various types of seafood. It can grow rapidly in shellfish, owing to the ambient air conditions occurring with intertidal exposure.[10] An evaluation of 306 seafood samples, including shrimp and mussels, from supermarkets in Berlin found an overall Vibrio prevalence of 56%; the species most commonly found in the samples was Vibrio parahaemolyticus, with only 4% of the samples harboring V vulnificus.[11]
A study of Vibrio species isolated from retail shrimp in Hanoi found that 201 of 202 samples were positive for Vibrio, with most containing V parahaemolyticus (96.5%) and far fewer (1.5%) containing V vulnificus.[12] Sanitary working conditions and thorough cooking of shrimp should be encouraged.
Vibrio species are common in aquatic environments; a study of diseased freshwater and ornamental fish in Poland identified six Vibrio species.[13]
In the United States, V vulnificus infections are rare but underreported. Most cases are found in the Gulf Coast states and occur predominantly during warm weather months. Since 2007, V vulnificus has been difficult to culture from North Carolina oyster samples. It may be that oysters were colonized with a more salt-tolerant bacterium during the drought, displacing V vulnificus and possibly preventing recolonization.[14] Evaluation of the graveyard skeletons of two American Civil War soldiers revealed they may have died as a result of V vulnificus bloodstream infection (BSI).[15]
A 2008 from Japan that evaluated the frequency of V vulnificus infection, which is rare in that country, found that the prevalence varied in different districts.[16] A 2017 study from India found that 10 (38.5%) of 26 clam (Meretrix meretrix) samples obtained from the markets in the attractive tourist destination of Mangalore harbored V vulnificus.[17] Marine aquaculture has rendered V vulnificus infections relatively common all over the world.[18]
Age-, sex-, and race-related demographics
All ages are affected equally. Males and females are affected equally. All races are affected equally.
Most V vulnificus infections are acute and cause no long-term adverse effects. With proper treatment (ie, antibiotics), the prognosis is often excellent. It must be kept in mind, however, that this organism is the cause of more than 95% of seafood-related deaths in the United States and has the highest fatality rate of any food-borne pathogen.[19]
Although most patients with V vulnificus infection experience no long-term consequences, mortality may be as high as 50% in patients who develop septic shock as a consequence of such infection. A 2017 case report described a man who became infected with V vulnificus after swimming in the Gulf of Mexico 5 days after the completion of a leg tattoo.[20] The patient died of septic shock; his chronic liver disease was cited as a possible contributing factor.
In rare instances, skin infection can result in necrotizing fasciitis. V vulnificus necrotizing skin and soft-tissue infections may result in multiple organ failure and death. A prediction model to estimate the case-fatality rate has been proposed.[21]
A retrospective analysis of 30 patients with necrotizing fasciitis and sepsis caused by Vibrio species and initially treated with surgical debridement or immediate limb amputation showed that 11 (37%) died within several days of admission.[22] Mortality was higher in the V cholerae non-O1 group (57%) than in the V vulnificus group (30%). Other bad prognostic signs included a systolic blood pressure of 90 mm Hg or lower, decreased platelet counts, and leukopenia. The combination of hepatic dysfunction and diabetes mellitus was also associated with a poor outcome.
Predictive factors for mortality in primary BSI or wound infection caused by V vulnificus have been accessed by using a variety of parameters. A multivariate analysis indicated that the presence of hemorrhagic bullae/necrotizing fasciitis, primary BSI, a greater severity of illness, absence of leukocytosis, and hypoalbuminemia were significant risk factors for mortality in V vulnificus skin and soft-tissue infections.[23]
Patients who are immunocompromised should be counseled regarding means of preventing exposure to V vulnificus. The high mortality associated with this infection suggests that susceptible individuals should be forewarned by signs displayed in restaurants. Physicians should educate patients with chronic liver disease about the risk posed by raw oyster consumption. Additionally, harvesting methods that reduce contamination by V vulnificus should be used.[24]
V vulnificus infection should be suspected in patients who give a history of ingestion of raw seafood or wound infection after exposure to seawater. Patients with V vulnificus infection report abrupt gastrointestinal (GI) symptoms (eg, vomiting, diarrhea, or abdominal pain) and may present with fever, chills, or shock. V vulnificus is normally found in warm estuarial and marine environments, lodging in filter feeders such as oysters. It occurs mainly in patients with chronic liver disease after the consumption of raw oysters. Partridge et al reported a case that was likely contracted from a thermal pool in Türkiye, with no history of seawater or shellfish exposure.[25]
V vulnificus bloodstream infection (BSI) is the most common cause of death from seafood consumption in the United States.[24] This may first become evident in the skin as purpura fulminans, which can take a catastrophic course without immediate and intensive empirical antibiotic treatment.[26]
V vulnificus infection is a rare cause of necrotizing fasciitis, which can be fatal.[27, 28] Necrotizing fasciitis caused by V vulnificus progresses more rapidly and with more fulminant clinical characteristics than that caused by either methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-sensitive S aureus (MSSA).[29] The same may be true for necrotizing fasciitis caused by V vulnificus as compared with that caused by Klebsiella pneumoniae (2.5 vs 5.5 d).[30]
Most patients infected with V vulnificus have bullous skin lesions, which are found on the trunk and the lower extremities (see the image below). Infection of the hand has been reported.[31] These hemorrhagic bullae can progress to necrotic ulcerations, for which surgical debridement is required. Edema can be present.
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Vibrio infections. Early bullous lesions appear over dorsum of foot of patient with cirrhosis.
A rapid onset of cellulitis may represent infection with V vulnificus, especially if the patient had contact with seawater or raw seafood. Patients can progress to necrotizing fasciitis.[32]
Patients who are immunocompromised are at risk of septic shock from the infection, which can be fatal. Otherwise, no complications from V vulnificus infection occur.
Routine stool, wound, and blood cultures aid in the diagnosis of V vulnificus infection. A polymerase chain reaction (PCR) assay is an excellent detection method for V vulnificus.[33]
The genomic characteristics of the human pathogen Vibrio cidicii, originally misidentified as V vulnificus in Baltic Sea samples, illuminate the value of whole-genome sequencing for confirming accurate classification of Vibrio species.[34]
Antibiotics are necessary to eradicate the infection (see Medication). A high index of suspicion is important, in that doxycycline, the antibiotic of choice, is not usually a part of empiric therapy for bloodstream infection (BSI). Tigecycline may be a good choice for treating invasive V vulnificus infections.[35]
In case of wound infection, aggressive debridement is necessary to remove necrotic tissue. If the patient is in shock, the interventions necessary to resuscitate the patient must be performed.
If necrotizing fasciitis is suspected, early fasciotomy and culture-directed antimicrobial therapy should be performed. These patients may develop hypotensive shock, leukopenia, severe hypoalbuminemia, and underlying chronic illness, especially a combination of hepatic dysfunction and diabetes mellitus. V vulnificus as the etiologic agent of necrotizing fasciitis requires emergency approaches to treat potential septic shock and multiple organ failure,[36] particularly in patients with preexisting medical complications (eg, hypotension, lactic acidosis, coagulation disorders, and thrombocytopenia).[37]
Available guidelines that may be helpful include the Practice guidelines for the diagnosis and management of skin and soft-tissue infections from the Infectious Diseases Society of America and the Diagnosis and management of foodborne illnesses: a primer for physicians and other health care professionals from the American Medical Association, American Nurses Association, American Nurses Foundation, Centers for Disease Control and Prevention, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Food Safety and Inspection Service, and US Department of Agriculture.[38, 39]
To prevent infection from V vulnificus, efforts should be made to avoid exposure to raw shellfish and to thoroughly cook any shellfish eaten. Cooked shellfish should be kept apart from uncooked shellfish so as to avoid cross-contamination. Shellfish is best served hot and should be eaten promptly after being cooked.[40] Identifying oysters that are affected by V vulnificus is difficult because the infection has no effect on the appearance, taste, color, or odor of the oysters. Through improved reporting of affected oysters, oyster beds that are affected can be identified and closed.[41]
Individuals who have wounds or broken skin must avoid exposing these areas to raw shellfish or infected waters.
Patients who are immunocompromised should be especially careful to take these preventive measures because they are more susceptible to infection and complications.
Chicken egg yolk anti–V vulnificus immunoglobulins have been shown to be effective for prophylaxis against and therapy for V vulnificus infections.[42]
Therapeutic vaccination against V vulnificus infection by active and passive immunization with the C-terminal region of the RtxA1/MARTXVv protein has been suggested on the basis of studies in mice.[43]
There is a need for a good natural food preservative or biocontrol agent to control V vulnificus in seafood, and the bacteriophage VVP001 has been suggested as a potential option.[44]
Because many patients with V vulnificus infection experience overwhelming sepsis,[2] consultation with an infectious disease specialist is warranted. Such consultation may also be considered if the diagnosis is unclear or if the patient has atypical symptoms or does not respond to antibiotic treatment.
What is Vibrio vulnificus infection?What is the pathophysiology of Vibrio vulnificus infection?What causes Vibrio vulnificus infection?What is the prevalence of Vibrio vulnificus infection in the US?What is the global prevalence of Vibrio vulnificus infection?What is the racial predilection of Vibrio vulnificus infection?What is the sexual predilection of Vibrio vulnificus infection?How does the prevalence of Vibrio vulnificus infection vary by age?What is the prognosis of Vibrio vulnificus infection?What is included in patient education about Vibrio vulnificus infection?Which clinical history findings are characteristic of Vibrio vulnificus infection?Which physical findings are characteristic of Vibrio vulnificus infection?What are the possible complications of Vibrio vulnificus infection?Which lab tests are performed in the diagnosis of Vibrio vulnificus infection?What is the role of imaging studies in the diagnosis of Vibrio vulnificus infection?How is Vibrio vulnificus infection treated?Which activity modifications are used in the treatment of Vibrio vulnificus infection?How is Vibrio vulnificus infection prevented?Which specialist consultations are beneficial to patients with Vibrio vulnificus infection?What is the role of medications in the treatment of Vibrio vulnificus infection?Which medications in the drug class Tetracyclines are used in the treatment of Vibrio vulnificus Infection?
Robert A Schwartz, MD, MPH, Professor and Head of Dermatology, Professor of Pathology, Professor of Pediatrics, Professor of Medicine, Rutgers New Jersey Medical School
Disclosure: Nothing to disclose.
Coauthor(s)
Cris Jagar, MD, Staff Physician, Department of Psychiatry, Trinitas Regional Medical Center
Disclosure: Nothing to disclose.
Specialty Editors
Jeffrey P Callen, MD, Professor of Medicine (Dermatology), Chief, Division of Dermatology, University of Louisville School of Medicine
Disclosure: Received income in an amount equal to or greater than $250 from: Biogen US (Adjudicator for study entry cutaneous lupus erythematosus); Priovant (Adjudicator for entry into a dermatomyositis study); IQVIA (Serono - adjudicator for a study of cutaneous LE) <br/>Received honoraria from UpToDate for author/editor; Received royalty from Elsevier for book author/editor; Received dividends from trust accounts, but I do not control these accounts, and have directed our managers to divest pharmaceutical stocks as is fiscally prudent from Stock holdings in various trust accounts include some pharmaceutical companies and device makers for these trust accounts for: Stocks held in various trust accounts: Allergen; Amgen; Pfizer; 3M; Johnson and Johnson; Merck; Abbott Laboratories; AbbVie; Procter and Gamble;; Celgene; Gilead; CVS; Walgreens; Bristol-Myers Squibb.
Chief Editor
Dirk M Elston, MD, Professor and Chairman, Department of Dermatology and Dermatologic Surgery, Medical University of South Carolina College of Medicine
Disclosure: Nothing to disclose.
Additional Contributors
Craig A Elmets, MD, Professor and Chair, Department of Dermatology, Director, Chemoprevention Program Director, Comprehensive Cancer Center, UAB Skin Diseases Research Center, University of Alabama at Birmingham School of Medicine
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: University of Alabama at Birmingham; University of Alabama Health Services Foundation<br/>Serve(d) as a speaker or a member of a speakers bureau for: Ferndale Laboratories<br/>Received research grant from: NIH, Veterans Administration, California Grape Assn<br/>Received consulting fee from Astellas for review panel membership; Received salary from Massachusetts Medical Society for employment; Received salary from UpToDate for employment. for: Astellas.
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