LB-2. Toxigenic V. cholerae O75 Multi-state Outbreak Associated with Raw Oyster Consumption, 2011
Session: Poster Abstract Session: Late Breaker Posters
Saturday, October 22, 2011
Room: Poster Hall B1

There are approximately 200 serogroups of Vibrio cholerae, but only toxigenic serogroups O1 and O139 cause the reportable disease cholera. Other serogroups of V. cholerae, such as O75 and O141, can be toxigenic (possess the cholera toxin gene) and cause severe diarrhea; these infections are not defined as cholera, however, and are reportable as vibriosis. Toxigenic V. cholerae O75 was first isolated from patients with diarrhea in the United States in 2000. During 2000-2009, an average of one case was reported annually; seven sporadic cases were reported in 2010. From March to May 2011, there was a multi-state outbreak of toxigenic V. cholerae O75 associated with consumption of seafood from the Gulf Coast.


State public health labs send suspect isolates of V. cholerae to the Centers for Disease Control and Prevention (CDC) for confirmation, cholera toxin testing, serogrouping, pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility testing.  CDC conducts surveillance for cholera and vibriosis through the Cholera and Other Vibrio Illness Surveillance (COVIS) system.  A probable case is clinically compatible and epidemiologically linked to a confirmed case.  COVIS report forms for confirmed and probable cases of toxigenic V. cholerae O75 from 2011 were reviewed.


From March to May 2011, 11 confirmed and one probable case of toxigenic V. cholerae O75 were reported to CDC from 6 states: FL (6 confirmed, 1 probable), IN (1), GA (1), LA (1), TN (1), and AL (1). Patients were aged 22 to 73 years (median 45 years), 42% were female and 82% were white.  There were no hospitalizations or deaths. Onset dates ranged from March 23 to May 10. All patients reported consuming raw or lightly cooked oysters from the Gulf Coast. Ten reported consuming oysters in Florida; 2 reported consuming oysters outside of Florida. The oysters were traced back to Apalachicola Bay, FL. All confirmed cases were related by PFGE and were susceptible to all antimicrobials tested.


This represents the first reported outbreak of toxigenic V. cholerae O75 infections in the United States. Toxigenic V. cholerae O75 illness is fairly rare; however, illness has become more common in the last few years. Consumption of raw oysters is a risk for illness.

Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Anna E. Newton, MPH1,2, Tiffiani Onifade, MS, PhD3, Richard Hutchinson3, L. Amanda Ingram, MPH4, John Dunn, DVM, PhD4, Tim F. Jones, MD4, Erin Delaune, MPH5, Melissa Tobin-D'Angelo, MD, MPH6, Dagny Magill, MPH7, Sherri Davidson, MPH7, Amie May, PhD(c), MSBS, MPH8, Molly Freeman, PhD1, Michele B. Parsons, MS1, Cheryl Bopp, MS1, Kathleen E. Fullerton, MPH1 and Barbara E. Mahon, MD9, (1)Centers for Disease Control and Prevention, Atlanta, GA, (2)Atlanta Research and Education Foundation, Decatur, GA, (3)Florida Department of Health, Tallahassee, FL, (4)Tennessee Department of Health, Nashville, TN, (5)Lousiana Office of Public Health, New Orleans, LA, (6)Georgia Division of Public Health, Atlanta, GA, (7)Alabama Department of Public Health, Montgomery, AL, (8)Indiana State Department of Health, Indianopolis, IN, (9)Centers for Disease Control and Prevention, Decatur, GA


A. E. Newton, None

T. Onifade, None

R. Hutchinson, None

L. A. Ingram, None

J. Dunn, None

T. F. Jones, None

E. Delaune, None

M. Tobin-D'Angelo, None

D. Magill, None

S. Davidson, None

A. May, None

M. Freeman, None

M. B. Parsons, None

C. Bopp, None

K. E. Fullerton, None

B. E. Mahon, None

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