Among 77 persons who consumed potluck food, 25 (33%) met the confirmed case definition, and four (5%) met the probable case definition. The median age of patients was 64 years (range = 9–87 years); 17 (59%) were female. Among 26 (90%) patients who reported onset dates, illness began a median of 2 days after the potluck (range = 1–6 days).
Twenty-seven of the 29 patients initially went to FMC. Twenty-two (76%) patients were transferred from FMC to six hospitals in the Columbus metropolitan area approximately 30 miles away; these transfers required substantial and rapid coordination. Twenty-five (86%) patients received botulinum antitoxin, and 11 (38%) required endotracheal intubation and mechanical ventilation; no other patients died. Within 1 week of the first patient’s arrival at the emergency department, 16 patients (55%) had been discharged. Among 19 cases that were laboratory-confirmed, serum and stool specimens were positive for botulinum neurotoxin type A or Clostridium botulinum type A.
Interviews were conducted with 75 of 77 persons who ate any of the 52 potluck foods. Consumption of any potato salad (homemade or commercial) yielded the highest association with probable or confirmed case status (risk ratio [RR] = 13.9; 95% confidence interval [CI] = 4.6–41.8), followed by homemade potato salad (RR = 9.1; CI = 3.9–21.2). Of 12 food specimens collected from the church dumpster, six were positive for botulinum neurotoxin type A; five contained potato salad and one contained macaroni and cheese that might have been contaminated after being discarded.
The attendee who prepared the potato salad with home-canned potatoes reported using a boiling water canner, which does not kill C. botulinum spores, rather than a pressure canner, which does eliminate spores (2). In addition, the potatoes were not heated after removal from the can, a step that can inactivate botulinum toxin. The combined evidence implicated potato salad prepared with improperly home-canned potatoes, a known vehicle for botulism (3).
This was the largest botulism outbreak in the United States in nearly 40 years (Table). Early recognition of the outbreak by an astute clinician and a rapid, coordinated response likely reduced illness severity and facilitated early hospital discharge. This outbreak response illustrates the benefits of coordination among responders during botulism outbreaks. Close adherence to established home-canning guidelines can prevent botulism and enable safe sharing of home-canned produce (2).
Acknowledgments
Fairfield Medical Center, Lancaster, Ohio; Fairfield Department of Health, Lancaster, Ohio; Ohio Department of Health (ODH) Bureau of Infectious Diseases, Columbus, Ohio; ODH Bureau of Public Health Laboratory, Reynoldsburg, Ohio; ODH Office of Preparedness, Columbus, Ohio; Franklin County Public Health, Columbus, Ohio; Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, CDC; Strategic National Stockpile, Office of Public Health Preparedness and Response, CDC; Office of Regulatory Affairs, CDC.
1Ohio Department of Health; 2Epidemic Intelligence Service, CDC; 3Division of Foodborne, Waterborne, and Infectious Diseases, National Center for Emerging and Zoonotic Infectious Diseases, CDC; 4Fairfield Department of Health; 5Fairfield Medical Center. Corresponding author: Carolyn L. McCarty, wmw8@cdc.gov, 614-728-6941.
References
Sobel J. Botulism. Clin Infect Dis 2005;41:1167–73.
National Center for Home Food Preservation, US Department of Agriculture. USDA complete guide to home canning, 2009 revision. Washington, DC: US Department of Agriculture; 2009. Available at http://nchfp.uga.edu/publications/publications_usda.htmlExternal Web Site Icon.
Sobel J, Tucker N, Sulka A, McLaughlin J, Maslanka S. Foodborne botulism in the United States, 1990–2000. Emerg Infect Dis 2004;10:1606–11.