Campylobacter jejuni (pronounced “camp-e-low-back-ter j-june-eye”) is a bacterium that was first recognized as a cause of human gastrointestinal illness in 1975. Since that time, the bacterium has been identified as the most common cause of bacterial foodborne illness in the U.S., ahead of Salmonella – the second most common cause (MMWR Weekly, 2000, March 17; Tauxe, 1992).

Over 10,000 cases are reported to the Centers for Disease Control and Prevention (CDC) each year; however, many more cases go undiagnosed or unreported and estimates are that Campylobacter causes 2 to 4 million cases per year in the United States. Active surveillance for cases indicates that over 20 cases for each 100,000 persons in the population are diagnosed yearly, and 124 deaths are attributed to C. jejuni annually (CDC, 2005, October 6). Current estimates are that each case of campylobacteriosis costs $920 on average due to medical and productivity (lost wages) expenses with an annual total cost of approximately $1 billion (CAST, 1994).

The CDC reported that the incidence of Campylobacter infection decreased by 30 percent in the ten-year period between 1996 and 2006 (MMWR, 2007, April 13).

Campylobacter jejuni is a gram-negative, microaerophilic, thermophilic rod that grows best at 42°C (107°F) and low oxygen concentrations. These characteristics are adaptations for growth in its normal habitat – the intestines of warm-blooded birds and mammals. Several closely related species with similar characteristics, C. coli, C. fetus, and C. upsalienis, may also cause disease in man but are responsible for less than one percent of human infections annually (CDC, 2005, October 6).

Food is the most common vehicle for the spread of Campylobacter, and chicken is the most common food implicated.  Contamination occurs during animal slaughter and processing when it comes into contact with animal feces.  Ingestion of as few as 500 organisms – an amount that can be found in one drop of chicken juice – has been proven to cause human illness (FSIS, 1996; Tauxe, 1992). 

Despite this low infectious dose and the prevalence of Campylobacter jejuni in the environment, most cases of Campylobacter infection occur as isolated, sporadic events, and are not usually a part of large outbreaks.  But, very large outbreaks (>1,000 illnesses) of campylobacteriosis have been documented, most often from consumption of contaminated milk or unchlorinated water supplies.

A 1998 Consumer Reports study identified Campylobacter in 63% of more than 1000 chickens obtained in grocery stores (Consumers Union, 1998), and other studies have documented Campylobacter contamination on up to 88 percent of chicken carcasses (FSIS, 1996; Tauxe, 1992).

Any raw poultry – chicken, turkey, duck, goose, game fowl – meat and its juices may contain Campylobacter, including organic and “free range” products.  Other identified food vehicles include unpasteurized milk, undercooked meats such as beef, pork, lamb, and livestock offal, and occasionally shellfish, fresh produce, and eggs. 

How is Campylobacteriosis diagnosed?

Many kinds of infections can cause diarrhea and the other symptoms associated with campylobacteriosis. Doctors can look for bacterial causes of diarrhea by asking a laboratory to culture a sample of stool from an ill person. Microbiology laboratories now routinely perform culture procedures on stool specimens that are specifically designed to promote the growth and identification of Campylobacter jejuni and the other species of Campylobacter. 

Many persons submit samples for culturing after they have started antibiotics, which may make it even more difficult for a lab to grow Campylobacter.  Blood cultures are often not performed and in most cases the blood stream is not infected.

Treatment for Campylobacter infection

Patients with Campylobacter infection should drink plenty of fluids as long as the diarrhea lasts in order to maintain hydration. Antidiarrheal medications such as loperamide may allay some symptoms.  Campylobacteriosis is usually a self-limited illness, but when it is identified specific treatment with antibiotics is indicated, as treatment may shorten the course of the illness.

In more severe cases of gastroenteritis, antibiotics are often begun before culture results are known. 

Macrolide antibiotics (erythromycin, clarithromycin, or azithromycin) are the most effective agents for Campylobacter jejuni.  Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin, gatifloxacin, or moxifloxacin) can also be used, but resistance to this class has been rising, at least in part due to the use of this class of antimicrobial in poultry feed (Smith, et al., 1999).  In the U.S. these antibiotics are available only by prescription.

If you believe you have become ill with campylobacteriosis, contact your health care provider.

Antimicrobial Resistance in Bacteria

Antimicrobial resistance in bacteria is an emerging and increasing threat to human health. Physicians should be aware that antimicrobial resistance is increasing in foodborne pathogens and that patients who are prescribed antibiotics are at increased risk for acquiring antimicrobial-resistant foodborne infections. In addition, “…increased frequency of treatment failures for acute illness and increased severity of infection may be manifested by prolonged duration of illness, increased frequency of bloodstream infections, increased hospitalization or increased mortality,” (Angulo, Nargund, & Chiller, 2004).

The use of antimicrobial agents in the feed of food animals is estimated by the FDA to be over 100 million pounds per year. Estimates range from 36 to 70 percent of all antibiotics produced in the United States are used in a food animal feed or in prophylactic treatment to prevent animal disease.  In 2002, the Minnesota Medical Association published an article by David Wallinga, M.D., M.P.H. who wrote:

According to the [Union of Concerned Scientists], 70 percent of all the antimicrobials used in the United States for all purposes—or about 24.6 million pounds annually—are fed to poultry, swine, and beef cattle for nontherapeutic purposes, in the absence of disease. Over half are “medically important” antimicrobials, identical or so closely related to human medicines that resistance to the animal drug can confer resistance to the similar human drug. Penicillins, tetracyclines, macrolides, streptogramins, and sulfonamides are prominent examples. (Wallinga, 2002).

The National Antimicrobial Resistance Monitoring System (NARMS) reported that Campylobacter has been recovered from 47 percent of chicken breasts tested in recent studies. In the same NARMS studies, five multi-drug resistant strains of Salmonella Newport were recovered from ground beef, ground turkey, and pork chops.

According to the report, “…antimicrobial resistance among these foodborne bacteria is not uncommon and often associated with the use of antimicrobial agents in food animals,” (Stevenson, et al., 2002).  Ceftriaxone-resistant Salmonella has also been reported (Fey, et al., 2000). The emergence of multidrug-resistant Salmonella Typhimurium in the United States is another example of a drug-resistant bacteria spreading from animals to humans (Glynn, et al., 1998).  CDC reports:

A large proportion of serotype Typhimurium isolates were resistant to multiple antimicrobial drugs; in a 2003 national survey, 45% were resistant to one or more drugs and 26% had a five-drug resistance pattern characteristic of a single phage type, DT104 (2). Similarly, serotype Newport has emerged as a major multidrug-resistant pathogen (CDC, 2007).

The use of antibiotics in feed for food animals, on animals prophylactically to prevent disease, and the use of antibiotics in humans unnecessarily must be reduced. European countries have reduced the use of antibiotics in animal feed and have seen a corresponding reduction in antibiotic-resistant illnesses in humans (Angulo & Baker, et al., 2004).

How to prevent Campylobacter infection

Campylobacter jejuni grows poorly on properly refrigerated foods, but does survive refrigeration and will grow if contaminated foods are left out at room temperature.  The bacterium is sensitive to heat and other common disinfection procedures; pasteurization of milk, adequate cooking of meat and poultry, and chlorination or ozonation of water will destroy this organism.  Infection control measures at all stages of food processing may help to decrease the incidence of Campylobacter infections, but the single most important and reliable step is to adequately cook all poultry products. 

The most reliable method to ensure this is to use a digital food thermometer.  Document that the thickest part of the chicken, turkey, duck or goose (the center of the breast) reaches 180°F or higher, as recommended by the U.S. Food and Drug Administration (CFSAN, 1996). The agency recommends at least 165°F for stuffing, 170°F for ground poultry products, and that thighs and wings be cooked until juices run clear.

Most cases of campylobacteriosis are sporadic or involve small family groups, although some common-source outbreaks involving many people have been traced to contaminated water or milk.  Other sources of Campylobacter include children prior to toilet-training, especially in child care settings, (Goossens, et al., 1995) and intimate contact with other infected individuals.  C. jejuni is commonly present in the gastrointestinal tract of healthy cattle, pigs, chickens, turkeys, ducks, and geese, and direct animal exposure can lead to infection.  Pets that may carry Campylobacter include birds, cats, dogs, hamsters, and turtles (Fang, Araujo & Guerrant, 1991).  The organism is also occasionally isolated from streams, lakes and ponds.

Other control measures of import that are available to consumers and food service personnel to prevent campylobacteriosis include the following (Scott & Sockett, 1998):

* Choose the coolest part of the vehicle (generally the trunk in winter and cab in summer) to transport meat and poultry home from the market.

* Defrost meat and poultry in the refrigerator. Place the item on a low shelf, on a wide pan, lined with paper towel; ensure that drippings do not land on foods below. If there is not enough time to defrost in the refrigerator, then use the microwave.

* Do not cook stuffing actually inside the bird.

* Rapidly cool leftovers.

* Never leave food out at room temperature (either during preparation or after cooking) for more than 2 hours.

* Avoid raw milk and products made from raw milk. Drink only pasteurized milk products.

* Wash hands thoroughly using soap and water, concentrate on fingertips and nail creases, and dry completely with a disposable paper towel at the following times:

* Wash after contact with pets, especially puppies, or farm animals (Fang, Araujo & Guerrant, 1991).

* Wash before and after preparing food, especially poultry.

* Wash after changing diapers or having contact with an individual with an intestinal infection.

* Wash children on arrival home from school or day-care.

* Wash fruits and vegetables carefully, particularly if they are eaten raw. If possible, vegetables and fruits should be peeled.

* Use pasteurized eggs. 

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