Information for Health Professionals

Incubation period is typically two to five days. Campylobacter infection is characterized by diarrhea (frequently bloody), abdominal pain, fever, nausea, and sometimes vomiting. More severe illness can occur, including bloodstream infection and symptoms mimicking acute appendicitis or ulcerative colitis.

This scanning electron microscopic (SEM) image depicts a number of Gram-negative Campylobacter jejuni bacteria, magnified 9,951x.

This image depicts Campylobacter jejuni magnified 9,951x. View larger >image icon

Campylobacter is a gram-negative, microaerophilic genus of bacteria of the family Campylobacteriacae. There are more than 20 species of Campylobacter, not all of which cause human illness. Approximately 90% of human Campylobacter illness is caused by one species, Campylobacter jejuni. Less common species, such as C. coli, C. upsaliensis, C. fetus, and C. lari, can also infect people.

Campylobacter jejuni grows best at 37°C to 42°C and seems to be well-adapted to birds, which have an approximate body temperature of 41°C to 42°C and can carry the bacteria without becoming ill.

These bacteria are fragile. They cannot tolerate drying. Freezing reduces the number of Campylobacter bacteria on raw meat.

Active surveillance through the Foodborne Diseases Active Surveillance Network (FoodNet) indicates that about 20 cases per 100,000 people are diagnosed each year. Many more cases go undiagnosed or unreported. CDC estimates that 1.5 million people in the United States become ill from Campylobacter infection every year.

Most people with Campylobacter infection recover completely within one week.

Campylobacter infection can result in long-term consequences, such as arthritis, irritable bowel syndrome (IBS), and Guillain-Barré syndrome (GBS). CDC estimates that only 0.2 to 1.7 in every 1,000 diagnosed and undiagnosed Campylobacter illnesses leads to GBS, but estimates Campylobacter are responsible for 5-41% of GBS illnesses

Most cases of Campylobacter infection occur after someone eats raw or undercooked poultry or another food that has been contaminated by raw or undercooked poultry. Outbreaks of Campylobacter infection are infrequently reported relative to the number of illnesses. Outbreaks have been associated with unpasteurized dairy products, contaminated water, poultry, and produce. People also can get infected from contact with dog or cat feces. Person-to-person spread of Campylobacter is uncommon.

A confirmed case is the isolation of Campylobacter spp. from a clinical specimen. A probable case is the detection of Campylobacter spp. in a clinical specimen using a culture-independent diagnostic test (CIDT), such as a polymerase chain reaction test.

The use of CIDTs as stand-alone tests for the direct detection of Campylobacter in stool is increasing. Data indicate that the sensitivity, specificity, and positive predictive value of these assays vary, depending on the manufacturer. Culture confirmation of CIDT-positive specimens (called reflex culture) can be used to obtain the whole genome sequence, which can provide antimicrobial susceptibility data and molecular subtyping.

Most infections are self-limited. Patients should drink extra fluids as long as the diarrhea lasts. Antimicrobial therapy may be used to treat people who are severely ill or at risk for severe disease.

People at risk for severe disease include people 65 years and older, pregnant women, and people with weakened immune systems, such as those with the blood disorders thalassemia and hypogammaglobulinemia, people with AIDS, and people receiving some kinds of chemotherapy.

Azithromycin and fluoroquinolones (e.g., ciprofloxacin) are commonly used for treatment, but resistance to fluoroquinolones is common. Antimicrobial susceptibility testing can help guide appropriate therapy.

Anyone can become infected with Campylobacter but infection is more common in males, children younger than 5 years, and people 65 years and older.

Campylobacter infections have been tracked passively through the National Notifiable Disease Surveillance System (NNDSS) since 1993 and actively since 2015 when these infections became nationally notifiable. FoodNet has conducted active surveillance for Campylobacter infections in sentinel sites since 1996. The National Antimicrobial Monitoring System (NARMS) monitors antimicrobial susceptibility to a range of antibiotics for a convenience sample of Campylobacter isolates from people. Campylobacter outbreaks are reported to CDC surveillance systems through the National Outbreak Reporting System (NORS).

FoodNet has tracked trends in Campylobacter infection since 1996. Campylobacter infections increased by 12% in 2018 compared with 2015–2017. More Campylobacter infections are probably being diagnosed because laboratories are using culture-independent diagnostic tests more often. It’s also possible that the number of infections is truly increasing.