Campylobacter Infection (Campylobacteriosis)

What Campylobacter is

Campylobacter is a curved, spiral-shaped bacterium that lives harmlessly in the intestines of many animals, especially poultry. Campylobacter jejuni causes most human infections. The CDC estimates it causes about 1.5 million illnesses in the US each year. A very small dose, as few as a few hundred bacteria, can cause illness.

How people get infected

• Undercooked chicken and turkey, or eating something that touched raw poultry (cutting boards, knives, hands). Most raw chicken sold in stores carries Campylobacter.
• Unpasteurized (raw) milk and products made from it.
• Untreated water from streams, wells or contaminated supplies.
• Contact with animals, especially puppies, kittens and farm animals with diarrhea.
• Travel to countries with poorer sanitation.

It rarely spreads directly from person to person, though it can spread through contact with an infected person's stool, for example when changing diapers.

Symptoms

Symptoms usually start 2 to 5 days after exposure (range 1 to 10 days):

• diarrhea, which may be watery or bloody
• cramping abdominal pain, sometimes severe and mimicking appendicitis
• fever
• nausea and sometimes vomiting
• headache, muscle aches and tiredness, sometimes before the diarrhea starts

Some people have no symptoms. People with weakened immune systems can develop bloodstream infections.

Diagnosis

A doctor diagnoses Campylobacter with a stool test: either a culture or a multiplex PCR panel that detects several gut germs at once. Testing is most useful for bloody diarrhea, fever, severe or prolonged illness, and outbreaks. Blood cultures are taken if the person is very unwell. Campylobacter is a reportable illness, so the local health department may follow up to identify the source.

Treatment

Fluids and rest

Most people recover without specific treatment.

• Drink plenty of fluids: water, broths and oral rehydration solutions replace both water and salts and are best for children, older adults and anyone with heavy diarrhea.
• Eat normally as soon as you feel able.
• Rest.
• Avoid anti-diarrhea medicines such as loperamide if you have bloody diarrhea or a high fever, unless a doctor advises them.

Antibiotics

Antibiotics shorten illness by about a day or so when started early, and are recommended for:

• severe illness, high fever or bloody diarrhea
• symptoms lasting more than a week
• pregnant people
• older adults and people with weakened immune systems

Azithromycin is the usual choice. Resistance to fluoroquinolones such as ciprofloxacin is now common, and increasing resistance to other antibiotics is being tracked by the CDC.

Complications

• Dehydration, the most common complication, especially in young children and older adults.
• Reactive arthritis: painful, swollen joints, sometimes with eye inflammation or painful urination, starting weeks after the infection. Usually settles within months.
• Guillain-Barré syndrome: Campylobacter is the most common identified trigger. It affects roughly 1 in 1,000 people with diagnosed Campylobacter infection, usually 1 to 3 weeks later, causing rising weakness and sometimes paralysis.
• Post-infectious irritable bowel syndrome: ongoing diarrhea, cramps or bloating.
• Bloodstream infection in people with weakened immunity.
• Miscarriage or stillbirth, rarely, in pregnancy.

Outlook

Most people recover fully within 2 to 10 days, although some relapse. Loose stools and tiredness can linger. People can carry the bacteria in their stool for several weeks after recovery, so careful handwashing is important.

Prevention

• Cook poultry to an internal temperature of 74 °C (165 °F); check with a food thermometer.
• Use separate cutting boards for raw meat and ready-to-eat foods, and wash hands, boards and knives in hot soapy water after handling raw poultry.
• Do not wash raw chicken; it spreads bacteria around the kitchen.
• Drink only pasteurized milk and treated water.
• Wash hands after touching animals, especially pets with diarrhea.
• Do not prepare food for others while you have diarrhea.

Frequently asked questions

What are the symptoms of Campylobacter?

Typical symptoms are diarrhea, often bloody, with cramping abdominal pain, fever, nausea and tiredness. They start 2 to 5 days after eating or drinking something contaminated and usually last about a week.

How long does Campylobacter last?

Most people recover in 2 to 10 days, typically about a week. Diarrhea can come back after initially improving. Bacteria can stay in the stool for a few weeks, so continue careful handwashing even after you feel better.

Do you need antibiotics for Campylobacter?

Usually not. Most healthy people recover with fluids and rest. Antibiotics, usually azithromycin, are recommended for severe or prolonged illness, bloody diarrhea with high fever, pregnancy, older age or weakened immunity.

Is Campylobacter contagious?

It spreads mainly through contaminated food, water and animal contact, and rarely from person to person. Spread can occur through contact with an infected person's stool, so wash hands thoroughly after using the toilet and changing diapers.

How do you get Campylobacter?

The most common source is undercooked chicken or food contaminated by raw poultry in the kitchen. Other sources include raw milk, untreated water, contact with animals, and travel. Proper cooking and kitchen hygiene prevent most infections.