The Campylobacteria are a group of organisms that usually cause mild to severe infections of the gastrointestinal system. Called “campylobacteriosis”, the illness typically causes symptoms like abdominal discomfort and frequent passage of stools, but sometimes symptoms can be severe. Watery or bloody diarrhea, fever, abdominal cramps, nausea, and vomiting can occur. In rare cases a complication called Guillain-Barre syndrome can lead to muscle weakness or paralysis about 2 weeks after first becoming ill.
The vast majority of campylobacter infections are food borne illnesses, and in fact it’s the leading cause of infective diarrhea worldwide in developed countries. The most common source is contaminated pork and poultry, which almost always harbor the bacteria without suffering from symptoms.
These infections can be passed from animals to humans in a few different ways, but understanding a bit about the infection can help you to avoid it. A few common-sense precautions are all you need.
The Source
Campylobacteria normally reside in the intestines of animals, where they may or may not cause illness. The animals raised for mass-produced meat are often given antibiotics to prevent illness, but campylobacteria has developed resistance to many of these drugs. Further, pigs and chickens often show no symptoms and pass the infection to their pen-mates.
The illness is transmitted through feces, where the animal sheds enormous amounts of infective material. When the animal is slaughtered it’s ridiculously easy for the meat to become contaminated, as the intestines are removed in a quick and messy process that allows feces and fluids to remain in close contact with the carcass. The U.N. Food and Agriculture Organization calls this sort of contamination “unavoidable”.
Undercooking and Cross-contamination
Since it’s almost inevitable that fresh chicken or pork will have campylobacter contamination, it’s a small step for the bacteria to get into a person. The most common ways are through undercooking or contaminating other food.
Undercooked meat can still contain live bacteria, and eating it transports the germs straight to their favored area—the intestines. Using a meat thermometer to ensure meat is cooked to 160 degrees F (72 degrees C) ensures all bacteria are dead, and is the most reliable technique. The appearance of the meat or “until the juices run clear” are not reliable indicators.
Cross-contamination happens when the cook handles contaminated meat and then handles other foods (like salad) without thoroughly washing, or cuts other raw foods using contaminated work surfaces and kitchen tools. This can be avoided by frequent hand washing and keeping all meats (and implements used on them) separate from foods eaten raw.
Water and Milk
Unpasteurized milk has caused campylobacter outbreaks, as has unchlorinated water. These are transmitted by unsafe milk collection procedures and water contaminated by livestock pens. This is uncommon in mass-produced foods, but travelers should be cautious in less-developed areas.
Farm and Meat Workers
Farm workers face a far higher chance of campylobacter exposure for a simple reason—the have to deal with animal feces. Hosing out, shoveling, or scraping animal waste will spread the bacteria into the air, onto their clothes, and microscopic particles may even enter their mouth and nose. Farm workers can actually become “reservoirs” for the bacteria, like Typhoid Mary, where the germs live in their intestines without causing any illness.
Meat processing workers can also become carriers. High levels of campylobacteria have been found on every surface in meat processing plants as well as in the air.
Pets
Unfortunately, even our pets can bring this illness into our homes. Feeding raw chicken or pork scraps to your dog or cat can give them the illness. They can also pick it up from eating birds or other kill, and if they have diarrhea and make a mess on the floor (or even in the litterbox) you can contract it while cleaning up. Be sure to thoroughly wash your hands and face after dealing with a pet’s accident or scooping out the litter.
An “Emerging Illness”
Campylobacter infection is considered an “emerging illness” by disease experts. This often means it’s a new illness that’s becoming more common, but in this case it’s likely a matter of better detection. The bacteria was first associated with diarrhea and other abdominal complaints over 100 years ago, but better testing has improved it’s identification many times over.
Unfortunately, it’s incidence has risen beyond what detection alone should account. Immune compromised people (like those undergoing chemotherapy, with advanced diabetes, AIDS patients, and transplant recipients) are most susceptible to infection. But if you use the basic care and hygiene steps above you should be able to prevent this illness.
http://www.cdc.gov/healthypets/diseases/campylobacteriosis.htm
http://www.ncbi.nlm.nih.gov/pubmed/2018709
https://attra.ncat.org/attra-pub/poultryprocess.html#ev
http://www.fao.org/docrep/010/ai407e/AI407E25.htm
http://digestive.niddk.nih.gov/ddiseases/pubs/bacteria/
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC120582/
http://www.cdc.gov/ncidod/eid/vol5no1/altekruse.htm
http://aac.asm.org/cgi/content/full/44/2/267
