ON AUGUST 29, 1996, the Jackson County Health Department (JCHD) in southwestern Oklahoma notified the Oklahoma State Department of Health (OSDH) of a cluster of Campylobacter jejuni infections that occurred during August 16-20 among persons who had eaten lunch at a local restaurant on August 15. This report summarizes the investigation of these cases and indicates that C. jejuni infection was most likely acquired from eating lettuce cross-contaminated with raw chicken. This report also emphasizes the need to keep certain foods and cooking utensils separate during food handling.
A case was defined as illness in a person who had eaten lunch at the restaurant on August 15, 1996, and had onset of diarrhea (i.e., three or more loose stools during a 24-hour period) or vomiting during August 16-20. Of 25 persons available for interview who had eaten lunch at the restaurant on August 15, a total of 14 (56%) had had an illness that met the case definition. The median age of patients was 33 years (range: 5-52 years); 10 (71%) were female. All patients reported diarrhea; 13 (93%), fever; 13 (93%), abdominal cramps; 11 (79%), nausea; five (36%), vomiting; and three (21%), visible blood in their stools. The median incubation period was 3 days (range: 1-5 days). Two (14%) patients were hospitalized. Stool specimens were collected from 10 patients; all yielded C. jejuni. No food items were available for testing.
To identify risk factors for illness, OSDH, in collaboration with JCHD, conducted a case-control study of 14 patients and 11 controls (i.e., persons who had eaten lunch with patients at the implicated restaurant on August 15 but did not become ill). Health department staff visited the restaurant to obtain information about menu items, to observe food preparation, and to inspect the kitchen.
All 14 patients and four (36%) controls reported eating lettuce (odds ratio [OR]=48.3; 95% confidence interval [CI]=2.3-∞; p <0.01). Eleven (79%) patients and three (27%) controls had eaten lasagna (OR=6.7; 95% CI=1.1-42.7; p <0.05). Both lettuce and lasagna were statistically associated with illness. Lettuce consumption accounted for all cases, and lasagna consumption accounted for 79% of cases.
Inspection of the restaurant indicated that the countertop surface area was too small to separate raw poultry and other foods adequately during preparation. The cook reported cutting up raw chicken for the dinner meals before preparing salads, lasagna, and sandwiches as luncheon menu items. Lettuce for salads was shredded with a knife, and the cook wore a towel around her waist that she frequently used to dry her hands. Bleach solution at the appropriate temperature (>75 F [>24 C]) and concentration (>50 ppm) was present to sanitize tables surfaces, but it was uncertain whether the cook had cleaned the countertop after cutting up the chicken. The lettuce or lasagna was probably contaminated with C. jejuni from raw chicken through unwashed or inadequately washed hands, cooking utensils, or the countertop.
JCHD recommended that the restaurant enlarge its food-preparation table and install a disposable hand towel dispenser and that food handlers wash hands and cooking utensils between use while preparing different foods.
TK Graves, MPH, KK Bradley, DVM, JM Crutcher, MD, State Epidemiologist, Oklahoma State Dept of Health. Foodborne and Diarrheal Diseases Br, Div of Bacterial and Mycotic Diseases, National Center for Infectious Diseases; Div of Applied Public Health Training (proposed), Epidemiology Program Office; and an EIS Officer, CDC.
Campylobacter is one of the most common causes of foodborne disease in the United States, causing approximately 2 million cases of gastroenteritis each year.1 Illness associated with Campylobacter infection is usually mild, but can be severe and even fatal. Although it did not occur in this outbreak, Guillain-Barre syndrome (GBS), a demyelinating disorder resulting in acute neuromuscular paralysis, is a serious sequela of Campylobacter infection.2 Up to 40% of patients with GBS have evidence of Campylobacter infection before onset of symptoms.2
Most illnesses associated with Campylobacter infection are sporadic. Common source outbreaks occur, and most have been traced to unpasteurized milk and contaminated drinking water.1 In comparison, most sporadic cases, and those in this outbreak, are associated with improper handling and preparing of poultry.1Campylobacter has been found in up to 88% of broiler chicken carcasses in the United States.1,3 The infectious dose of Campylobacter is low; ingestion of only 500 organisms, easily present in one drop of raw chicken juice, can result in human illness.1 Therefore, contamination of foods by raw chicken is an efficient mechanism for transmission of this organism.
Restaurants provide opportunities for outbreaks of foodborne disease because large quantities of different foods are handled in the same kitchen. Failure to wash hands, utensils, or countertops can lead to contamination of foods that will not be cooked. The food handler involved in this outbreak had not received training in food safety. The Food and Drug Administration has developed guidelines for food handlers to prevent cross-contamination of foods; however, states are not required to adopt these guidelines.4
Laws mandating certification of food-service employees differ by state. Twelve states have requirements for certification of food-service managers in all jurisdictions, 21 states have requirements in some jurisdictions, and 17 states have no requirements.5 Of 33 states for which information is available, only two have statewide requirements for training of food handlers.5
States can reduce the risk for foodborne illness in restaurants by ensuring that restaurant employees receive training in food safety. For example, food handlers should be aware that pathogens can be present on raw poultry and meat and that foodborne disease can be prevented by adhering to the following measures: (1) raw poultry and meat should be prepared on a separate countertop or cutting board from other food items; (2) all utensils, cutting boards, and countertops should be cleaned with hot water and soap after preparing raw poultry or meat and before preparing other foods; (3) hands should be washed thoroughly with soap and running water after handling raw poultry or meat; and (4) poultry should be cooked thoroughly to an internal temperature of 180 F (82 C) or until the meat is no longer pink and juices run clear.
Outbreak of Campylobacter Enteritis Associated With Cross-Contamination of Food—Oklahoma, 1996. JAMA. 1998;279(17):1341. doi:10.1001/jama.279.17.1341-JWR0506-2-1