Campylobacter Infection
Campylobacter Infection
Disease History, Characteristics, and Transmission
Introduction
The infection that is caused by the group of bacteria in the genus Campylobacter is called campylobacteriosis. The infection, which occurs in the intestinal tract of humans, causes abdominal pain and diarrhea. Campylobacter jejuni is responsible for more bacterial diarrhea in the United States than any other bacteria, and estimates are that upwards of 14% of all diarrhea worldwide is due to campylobacteriosis.
Campylobacter infections typically result from eating contaminated food or drinking contaminated water. The bacteria need time to grow to numbers that produce the symptoms of the infection; this is usually two to five days after the contaminated food or water has been ingested.
Disease History, Characteristics, and Transmission
It has been known for decades that Campylobacter bacteria are pathogenic, that is, they are capable of causing illness. For example, the capability of the bacteria to cause disease in animals has been known since the first decade of the twentieth century. But, the identity of Campylobacter as human pathogens has only been known since the 1980s.
According to the United States Centers for Disease Control and Prevention (CDC), more than 10,000 Campylobacter infections are reported each year. Considering that the symptoms of nausea, fever, abdominal cramps, vomiting, and diarrhea are often not reported or are not even diagnosed, the actual number of cases is not doubt much higher. Indeed, CDC's own estimate is that the number of infections in the U.S. number in the millions each year.
The symptoms of Campylobacter infections are not usually life-threatening in the developed world, where the level of health and sanitary conditions are better than in underdeveloped and developing countries. Most people who become infected recover in about a week or less without the need of medical aid. Still, even in countries such as the United States, severe Campylobacter infections occur, producing bloody diarrhea (as intestinal cells are damaged). Some people can have abdominal cramps for several months after an infection. The fluid loss from the diarrhea can dehydrate a person if enough fluids are not taken in; in severe cases that require hospitalization, the fluid may need to be supplied intravenously. Very rarely, a high fever that accompanies an infection will trigger a seizure. Also, in an estimated one case in every 1,000, Campylobacter infection contributes to a neurological disorder called Guillain-Barré syndrome, where a person's own immune system attacks the nerves, producing paralysis.
WORDS TO KNOW
MYCOTIC: Mycotic means having to do with or caused by a fungus. Any medical condition caused by a fungus is a mycotic condition, also called a mycosis.
PATHOGENS: Agents or microorganisms causing or capable of causing disease.
ZOONOSES: Zoonoses are diseases of microbiological origin that can be transmitted from animals to people. The causes of the diseases can be bacteria, viruses, parasites, and fungi.
IN CONTEXT: PERSONAL RESPONSIBILITY AND PREVENTION
The Division of Bacterial and Mycotic Diseases, Centers for Disease Control and Prevention (CDC) recommends the following tips for preventing Campylobacteriosis:
Cook all poultry products thoroughly. Make sure that the meat is cooked throughout (no longer pink), any juices run clear, and the inside is cooked to 170°F (77°C) for breast meat, and 180°F (82°C) for thigh meat.
If you are served undercooked poultry in a restaurant, send it back for further cooking.
Wash hands with soap before handling raw foods of animal origin. Wash hands with soap after handling raw foods of animal origin and before touching anything else.
Prevent cross-contamination in the kitchen:
- Use separate cutting boards for foods of animal origin and other foods. Carefully clean all cutting boards, countertops, and utensils with soap and hot water after preparing raw food of animal origin.
- Avoid consuming unpasteurized milk and untreated surface water.
- Make sure that persons with diarrhea, especially children, wash their hands carefully and frequently with soap to reduce the risk of spreading the infection.
- Wash hands with soap after having contact with pet feces.
SOURCE: Centers for Disease Control and Prevention (CDC)
Scope and Distribution
Campylobacter infections are an example of a zoonosis— an illness or disease that is transmitted to humans by animals or animal products. This is because Campylobacter is a natural resident in the intestinal tracts of creatures including swine, cattle, dogs, shellfish, and poultry. The animals harbor the bacteria without any ill effect. The bacteria also naturally inhabit the soil.
Treatment and Prevention
Campylobacter is readily susceptible to fairly conventional antibiotics. Treatment is not routinely done, as symptoms usually ease within a few days.
Preventing infection from the ingestion of contaminated food or water is a greater challenge. Poultry are an important source of the infection. Over 50% of raw chicken is contaminated with Campylobacter. During slaughter, the intestinal contents (including Campylobacter) can contaminate the carcass. If the chicken is undercooked, the bacteria can survive and can cause an infection after being ingested. Fortunately, the bacteria do not tolerate temperatures that are even slightly above room temperature (approximately 68°F [20°C]). Proper cooking of food kills the bacteria. Washing a cutting board after exposure to poultry, refrigeration of raw meat and poultry, and the thawing of meat in the refrigerator or microwave are efficient ways to prevent the transfer of Campylobacter to other foods.
Impacts and Issues
Research into Campylobacter infections consists primarily of genetic studies that are aimed at detecting genes of particular importance in the infection process. It is hoped that this knowledge will led to strategies to block the infection or to rapidly detect the presence of the bacteria on food products. One example of the latter approach is the incorporation of a detection system into food packaging. The presence of living bacteria is evident as a color change in an indicator strip in the packaging.
The United States Department of Agriculture carries out research on how to prevent Campylobacter infection from poultry. Organizations, including the CDC, maintain surveillance programs that help determine how often Campylobacter disease occurs, and factors that favor development of the infection.
In 1982, Centers for Disease Control and Prevention (CDC) began a national Campylobacter surveillance program in 1982. The program was revised in 1996 to further identify risk factors. In 2005 the Food and Drug Administration (FDA) revised its Model Food Code with hopes that the guide could reduce the risk of exposure to contaminated chicken. Exposure is not only risky and costly to those infected, but can potentially ruin or severely impact business and earnings for a commercial food establishment (and impact the people employed, etc.).
As with other pathogenic bacteria, researchers work to discover or manufacture antibiotics that are more adept at killing the bacteria without promoting the development of resistance to the antibiotic by the target bacteria.
See AlsoFood-borne Disease and Food Safety.
BIBLIOGRAPHY
Books
Ketley, Julian. Campylobacter. New York: Taylor & Francis, 2005.
Periodicals
Durham, Sharon. “Finding Solutions to Campylobacter in Poultry Production.” Agricultural Research.54 (2006): 10–11.
Price, Lance B., Elizabeth Johnson, Rocia Vailes, Ellen
Silbergeld. “Fluoroquinolone-resistant Campylobacter Isolates from Conventional and Antibiotic-free Chicken Products.” Environmental Health Perspectives. 113 (2005): 557–561.
Web Sites
Food and Drug Administration. “Model Food Code:2005 Recommendations of the United States Public Health Service Food and Drug Administration.” <http://www.cfsan.fda.gov/∼dms/fc05-toc.html> (accessed April 2007).
Brian Hoyle