Campylobacter

Campylobacter species are widely distributed in most warm-blooded animals. They are prevalent in food animals such as poultry, cattle, pigs, sheep and ostriches. They are also prevalent in pets, including cats and dogs². The bacteria have also been found in shellfish.

Campylobacter has a low infective dose (less than 500), which means that coming into contact with a few bacteria can cause illness. Patients infected with Campylobacter may experience mild to severe illness. Symptoms may include (bloody) diarrhea, abdominal pain, fever, headache, and nausea. The mean duration of illness is 2–5 days but can be up to 10 days. Infection can be associated with serious complications.
 
The most common are C. jejuni and C. coli and are responsible for gastroenteritis in humans. The other emerging species such as C. consicus, C. upsaliensis, C. ureolyticus, C. hyointestinalis and C. sputorum have been associated with gastroenteritis and periodontitis. In some cases, infection of the gastrointestinal tract by these bacteria can progress to life-threatening extra-gastrointestinal diseases^{3, 4}. C. jejuni is also considered as one of the most common risk factors for developing Guillain-Barré syndrome (GBS), a rare autoimmune disorder in which a person’s own immune system damages the nerves, causing muscle weakness and sometimes paralysis and even fatality. About 1 in every 1,000 reported Campylobacter illnesses leads to GBS and its symptoms may last for a few weeks to several years. Campylobacter infection leads up to 40% of GBS cases in the United States⁵.

It is often difficult to trace the sources of exposure to Campylobacter; which is due to the sporadic nature of the infection and the important role of cross-contamination. 

The presence of Campylobacter in a ready to eat (RTE) food is considered potentially injurious to health. Various internationally recognized methods (ISO standards) are used for the detection and enumeration of Campylobacter species, such as ISO 10272-1:2017 for detection and ISO 10272-2:2017 for enumeration⁶.

The enrichment culture methods uses Bolton Broth which allows resuscitation and recovery of injured organisms⁷ for accurate detection and enumeration. The traditional detection method gives presumptive results in three days, however for confirmed results, additional morphological, biochemical and growth tests are required which takes three days.

Various alternative diagnostic methods are currently used to save time and labor, and have led to enhanced detection, identification, and quantification of a broad range of Campylobacter species, such as immunological tests using antibodies that can be used to capture the target antigen and fully automated Enzyme-linked Immuno-Sorbent Assay (ELISA) test and Polymerase chain reaction (PCR).

A more recent and rapid identification method, MALDI-TOF MS, identifies a microorganism based on its unique protein profile.

The food industry can prevent Campylobacter contamination by using a proactive approach and food safety standards, such as HACCP (Hazard Analysis Critical Control Point) and Environmental Monitoring Programs (see our expert point of view on Environmental Monitoring Program). Most of the regulatory requirements mandate the sampling of meat products for Campylobacter testing at different stages, such as in raw and finished products.

Food manufacturing processes such as heating, freezing, or chilling can cause sub-lethal injury to Campylobacter species, resulting in increased sensitivity to antibiotics and lower resistance to elevated temperatures.

Campylobacter contamination of raw poultry products occurs during slaughter operations, as well as during the live-animal rearing process (e.g., on-farm contamination can coat the exterior of the bird and remain attached to the skin). Contamination can be minimized with the use of proper sanitary dressing procedures.

To keep under control the contamination of carcasses during the slaughtering process, a new process hygiene criterion for Campylobacter in broiler carcasses is laid out in Regulation (EC) No. 2017/1495 since January 1, 2018. These control measures aim to reduce the prevalence in poultry farms.

Most people with a Campylobacter infection recover without specific treatment and treatment is not generally required, except electrolyte replacement and rehydration. Patients should drink extra fluids as long as the diarrhea lasts. Antibiotics are needed only for patients who are very ill or at high risk for severe disease, such as people with severely weakened immune systems. However, the increasing drug resistance among different Campylobacter species poses a challenge for treatment of Campylobacteriosis. Due to high occurrence of acquired ciprofloxacin resistance in Campylobacter however, this drug will not be effective for treatment of Campylobacter infections in many countries.

The common industries affected by Campylobacter are food, agriculture and pharmaceutical. These species pose a significant risk of zoonotic transmission due to their ability to colonize farm animals (cattle and pigs); companion animals (such as dogs and cats) and wild animals (birds such as ducks and gulls) and therefore can be found in many foods of animal origin. Campylobacter is also commonly present in all avian species fit for human consumption. Campylobacter infections have been associated most often with poultry, raw (unpasteurized) dairy products, untreated water, and produce. Poultry is a common source of infection. Eating undercooked chicken, or ready-to-eat foods that have been in contact with raw chicken, is the most common source of infection.

Campylobacter is responsible for zoonoses and the transmission occurs via the fecal-oral route through ingestion of contaminated food and water. The primary environmental niche is represented by the intestinal tract of all avian species, mainly poultry (i.e. broilers, laying hens, turkeys, ducks, and ostriches) which is considered the main route of transmission. The consumption of their meat, in fact, represents 50-70% of human cases of Campylobacteriosis. Even the consumption of raw milk, raw red meat, fruits, and vegetables, and shellfish has been identified as a possible cause of transmission of this disease.