Outbreak of campylobacteriosis associated with consumption of raw peas

Clin Infect Dis. 2011 Jul 1;53(1):26-32. doi: 10.1093/cid/cir249.


Background: Campylobacter jejuni is a leading cause of acute gastroenteritis worldwide, and most cases are identified as sporadic events rather than as parts of recognized outbreaks. We report findings from a substantial 2008 campylobacteriosis outbreak with general implications for fresh produce safety.

Methods: We conducted a matched case-control study to determine the source of the outbreak and enhanced surveillance to identify additional cases. Clinical and environmental specimens were tested for Campylobacter, and isolates were subtyped by pulsed-field gel electrophoresis (PFGE).

Results: By routine surveillance, we identified 63 cases of laboratory-confirmed infection. Only raw peas, consumed by 30 (67%) of 45 case-patients and by 15 (17%) of 90 control participants, were associated with illness (adjusted odds ratio: 8.2; P<.001). An additional 69 patients (26 laboratory-confirmed) who reported eating raw peas within 10 days of illness onset were identified through enhanced surveillance. In all, 5 cases were hospitalized, and Guillain-Barré syndrome developed in 1 case; none died. The implicated pea farm was located near a Sandhill crane (Grus canadensis) stopover and breeding site. Of 36 environmental samples collected, 16 were positive for C. jejuni-14 crane-feces samples and 2 pea samples. We identified 25 unique combined SmaI-KpnI PFGE patterns among clinical isolates; 4 of these combined PFGE patterns identified in 15 of 55 human isolates were indistinguishable from PFGE patterns identified in environmental samples.

Conclusions: This investigation established a rare laboratory-confirmed link between a campylobacterosis outbreak and an environmental source and identified wild birds as an underrecognized source of produce contamination.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Agriculture
  • Alaska / epidemiology
  • Animals
  • Birds
  • Campylobacter Infections / epidemiology*
  • Campylobacter Infections / etiology
  • Campylobacter jejuni / isolation & purification
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Cluster Analysis
  • Disease Outbreaks*
  • Electrophoresis, Gel, Pulsed-Field
  • Feces / microbiology
  • Female
  • Foodborne Diseases / epidemiology*
  • Foodborne Diseases / etiology
  • Gastroenteritis / epidemiology*
  • Gastroenteritis / etiology
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Peas / microbiology*
  • Population Surveillance
  • Risk Factors