Vibrio Infections

Key Features

• Vibrios other than Vibrio cholerae that cause human disease are V parahaemolyticus, V vulnificus, and V alginolyticus

• Infection is acquired by exposure to organisms in raw or undercooked crustaceans or shellfish and warm (> 20°C) ocean waters and estuaries

• Oysters are implicated in up to 90% of food-related cases

Clinical Findings

• V cholerae

  • Causes voluminous diarrhea, rapid development of marked dehydration, and death if untreated

  • Rehydration and antimicrobial therapy are life-saving

• V parahaemolyticus

  • Causes acute watery diarrhea with fever, typically within 24 h after ingestion of contaminated shellfish

  • Disease is self-limited

  • Antimicrobial therapy usually not necessary

• V vulnificus and V alginolyticus

  • Neither cause diarrhea

  • They do, however, cause cellulitis and primary bacteremia after ingestion of contaminated shellfish or exposure to seawater

  • Cellulitis with or without sepsis may occur with

    • Bulla formation

    • Necrosis

    • Extensive soft tissue destruction, at times requiring débridement and amputation

  • Infection can progress rapidly and be severe in immunocompromised individuals, especially those with cirrhosis, with death rates of 50%

Diagnosis

• Culture

Treatment

• Tetracycline, 500 mg orally four times a day for 7–10 days, is the drug of choice for suspected or documented primary bacteremia or cellulitis caused by Vibrio species

• Vibrio cholerae is also susceptible to

  • Doxycycline, 100 mg twice daily orally for 7–10 days

  • Fluoroquinolones and TMP-SMZ

• V vulnificus may also be susceptible to

  • Penicillin

  • Ampicillin

  • Cephalosporins

  • Chloramphenicol

  • Aminoglycosides

  • Fluoroquinolones

• V parahaemolyticus and V alginolyticus

  • Resistant to penicillin and ampicillin

  • Otherwise, susceptibilities are similar to V vulnificus