Campylobacter Bacteria

Campylobacter is a genus of bacteria, family Spirillaceae. This group of bacteria derives its name from the Greek word Kampylos meaning "curved rod." There are many species of Campylobacter and in recent years the classification has changed considerably. Members of this group are animal parasites or pathogens frequently isolated from clinically healthy and diarrheic animals. The bacteria are curved or helical in shape which can swim rapidly by means of thin filaments (flagella) that act like propellers. The cells are about 2 micrometers long.³

Campylobacter spp. are found worldwide. Campylobacter fetus has been reported wherever sheep and cattle are kept and also has caused abortions in mink, goats, and horses. Campylobacter jejuni and Campylobacter coli occur naturally among wild and domestic birds and sometimes cause diarrhea.

Wild and domestic birds are considered as major reservoir of Campylobacter. These bacteria have been found in 35% of migratory birds, 50% of town-dwelling pigeons, and 20%-70% of gulls.

Campylobacter species have complex nutritional requirements. They utilize amino acids and organic acids as energy sources and are often isolated from sediments where they use a variety of oxidized nitrogen and sulfur compounds including elemental sulfur. Hydrogen and formate are the preferred energy sources under anaerobic conditions; acetate is a good carbon source.¹

Human Pathogens

Several species of Campylobacter cause disease: C. coli, C. jejuni, C. lari, C. upsaliensis for example, although most human cases of campylobacteriosis are caused by C. jejuni. Many species of this group of bacteria produce almost identical symptoms which are similar to those caused by Salmonella. Campylobacter is somewhat unusual in that one possible complication of the disease is Guillain-Barré (G-B) syndrome, a relatively rare neurological disease characterized by progressive weakening of the muscles. Although other bacteria can trigger G-B syndrome, Campylobacter is thought to be responsible for nearly half of all G-B cases in the United States.²

Campylobacter jejuni is a major human pathogen. It is acquired from an infected person or a domestic animal (usually a cat), food (poultry, meat, and milk), or water and colonizes the intestines where it produces symptoms that very similar to those seen in diarrheal diseases. In humans, a flu-like illness with fever, malaise, etc. will often precede the development of cramping watery and often bloody diarrhea. Severe abdominal pain can be confused with appendicitis. Vomiting is uncommon. A reactive arthritis may also occur after resolution of the diarrheal illness. The bacteria secrete an exotoxin that is similar to cholera toxin.^1,4 Mortality rates associated with C. jejuni in the US have been estimated at 1 per 1000 cases. Bacteremia can occur in the elderly⁵ The infection may be transmitted from person to person by sexual contact.⁶

Zoonotic Pathogen

Campylobacter jejuni is a cause of canine diarrhea. The bacteria are found much more often in puppies than mature dogs and even more often in kennel populations than among household dogs. Young children have closer exposure to sick puppies and are, therefore, more susceptible to fecal-oral transmission. C. jejuni is sensitive to a wide variety of antibiotics.⁴

Turtles, in addition to being carriers of Salmonella species, may also carry C. fetus which can cause meningitis and proctitis in humans. Pet ferrets can transmit several zoonotic diseases to humans, including campylobacteriosis. Cats with diarrhea pose a great zoonotic risk with young cats more likely being the carriers.⁴ C. coli infections have been implicated in the development of meningitis, septicemia, and abortions. C. upsaliensis causes abscesses, while C. showde, C. rectus, C. curvus, and C. concisus have been isolated from persons with periodontal disease.

Food Contaminant

Fresh poultry is more heavily contaminated than frozen, although the bacteria have also been isolated from beef, pok, lamb, raw milk, shellfish, mushrooms and salads. Campylobacter is unique among food-poisoning bacteria in that it is not normally able to grow in foods. This is because it has specific atmospheric requirements for growth and can only grow at temperature above ambient. The temperature range for growth is 30-45°C. The bacteria can survive for a short time at refrigeration temperature, but die out slowly at freezing temperature.⁵

References

2. The Microbial World by Roger Y. Stanier, John L. Ingraham, Mark L. wheelis, Page R. Painter
3. Microbiology: Diversity, Disease, and the Environment by Abigail A. Salyers, Dixie D. Whitt
4. Life at Small Scale: The Behavior of Microbes by David B. Dusenbery
5. nfections of Leisure by David Schlossberg
6. The food safety hazard guidebook By Richard Lawley, Laurie Curtis, Judy Davis
7. Textbook of Microbiology & Immunology By Parija