During the period studied, the poultry plant processed 300,000–350,000 birds per day and employed ≈1,000 persons who worked in 2 main processing areas: first processing and second processing. In first processing, birds were unloaded, shackled (in an area called live hang), stunned, killed, scalded, defeathered, eviscerated, and chilled. In second processing, carcasses were rehung, washed, cooled, and packaged. The plant was under the regulatory authority of the Food Safety and Inspection Service of the US Department of Agriculture. At any given time, the plant employed 24–35 persons who were residents of 1 of 2 local diversion centers (i.e., participants of a 16- to 20-week residential work assignment program operated by the Virginia Department of Corrections). The plant had a medical office, with limited diagnostic capabilities, staffed by licensed practical nurses. Employees requiring additional medical evaluation were referred to outside providers.
Using occupation data in Virginia Department of Health case reports and Virginia Department of Corrections records, we identified persons who had laboratory-diagnosed Campylobacter infection while employed at the plant during January 2008–May 2011. To capture all possible cases, we defined a case-patient as a plant employee with Campylobacter infection diagnosed by culture or enzyme immunoassay. We reviewed case-patient records from the Virginia Department of Health, Virginia Department of Corrections, and local medical providers and obtained additional work history information from the plant.
To determine the background incidence of reported gastrointestinal illness among plant employees, we reviewed encounter records (for January 2010–September 2011) from the plant’s medical office. We categorized an encounter as gastrointestinal illness–related if the employee reported diarrhea, abdominal cramps, nausea, or vomiting without another reason listed, such as nausea related to pregnancy or migraine headaches. We then tabulated gastrointestinal illness–related encounters by month.
We identified 29 cases of laboratory-diagnosed Campylobacter infection during January 2008–May 2011 in persons employed at the poultry-processing plant. Of the 29 persons, 23 were infected with C. jejuni, 1 was infected with C. coli, and 5 were infected with an unspecified Campylobacter species. Twenty-seven cases were diagnosed by stool culture; 2 were diagnosed by stool enzyme immunoassay.
The median age of case-patients was 29 years (range 19–52 years); 28 (97%) were men. Twenty-six (90%) case-patients were residents of a diversion center, and 3 lived at a private residence. Of the 29 case-patients, 27 (93%) worked in first-processing areas, including the live-hang (n = 18), evisceration (n = 8), and kill (n = 1) rooms, and 2 worked in second-processing areas, including the rehang (n = 1) and cut-up (n = 1) rooms. Twenty-four (83%) case-patients worked at the plant for <1 month before illness onset.
We obtained medical records for 24 case-patients, 3 of whom reported having been sought care in the plant medical office. These 24 case-patients were all reported to have had diarrhea while sick. Other signs and symptoms included abdominal cramping (n = 14), fever (n = 9), nausea and vomiting (n = 6), headache (n = 7), and muscle aches (n = 3). Of the 29 case-patients, 1 was hospitalized; there were no deaths. shows the number of cases by month of symptom onset.
Number of laboratory-diagnosed Campylobacter infections, by month of illness onset, in employees at a poultry-processing plant, Virginia, USA, 2008–2011.
In 2010, a total of 1,716 encounters at the plant’s medical office were recorded; 273 (16%) were associated with gastrointestinal symptoms. During January 2011–September 2011, a total of 1,543 encounters at the plant’s medical office were recorded, of which 221 (15%) were related to gastrointestinal symptoms (). Multiple peaks of visits for gastrointestinal illness were seen during summer 2010 and winter 2010–11, and a smaller peak occurred in summer 2011. Most other reasons for plant medical office visits were for injury reporting, first aid, and musculoskeletal symptoms.
Number of gastrointestinal illness–related visits to the medical office in a poultry-processing plant, Virginia, USA, 2008–2011.