NAME: Yersinia enterocolitica
SYNONYM OR CROSS REFERENCE: Yersiniosis, enterocolitis
CHARACTERISTICS: This bacterium is a gram negative, coccoid shaped, non spore-forming bacillus of the genus Yersinia, family Enterobacteriaceae Footnote 1, Footnote 2. It is a facultative anaerobe and is motile at room temperature but non-motile at 37 ºC Footnote 2. Strains are usually 0.5-0.8 µm by 1-3 µm in size Footnote 2. There are 6 biotypes (1A, 1B, 2, 3, 4 and 5 based on their genomic sequence) containing 50 different serogroups of Yersinia enterocolitica; however, only certain serogroups are pathogenic for humans Footnote 3, Footnote 4. The serogroups are group serotypes that share the same surface antigens and are categorized according to which O-antigen they express Footnote 1. Serogroups O:3 and O:9 are responsible for outbreaks in Europe, whereas O:8 is found in the US and O:5 and O:27 are found in Canada and Japan Footnote 3.
PATHOGENICITY/TOXICITY: Yersinia enterocolitica infection is characterized by enteritis, enterocolitis (particularly in children), fever (39ºC), watery stools, abdominal pain and acute mesenteric lymphadenitis (which may mimic appendicitis) Footnote 3, Footnote 5, Footnote 6. In some cases acute terminal ileitis and enteric fever can occur Footnote 3, Footnote 5. 1-3 weeks after the initial clinical symptoms, reactive arthritis and erythema nodosum may occur which can last about 6 months after infection Footnote 3. In rare instances, complications can include meningitis, endophthalmitis, conjunctivitis, myocarditis, pneumonia, pulmonary abscess, hepatitis, cholangitis, peritonitis, glomerulonephritis, urethritis, cellulitis, haemolytic anaemia, thyroiditis, pharyngitis and septicaemia Footnote 2, Footnote 3, Footnote 6. The infection is a greater health risk for immunosuppressed individuals and if untreated, the mortality rate due to septicaemia can be up to 50% Footnote 3.
EPIDEMIOLOGY: The disease is spread worldwide although it is less common in tropical areas Footnote 2, Footnote 3. Certain serogroups (O:3 and O:9 in Europe, O:8 in the US and O:5 and O:7 in Japan and Canada) are specific to different geographical areas Footnote 3.It is common year-round but reaches its peak in fall and winter Footnote 3.
HOST RANGE: Yersinia enterocolitica has been found in humans, warm blooded animals (particularly in farm animals and pets), birds and rarely in reptiles, fish and shellfish Footnote 2, Footnote 3. It has been found in the intestinal tracts of pigs, dogs and cats without any clinical manifestations Footnote 3.
INFECTIOUS DOSE: The infectious dose is of 108 bacteria or more orally Footnote 7.
MODE OF TRANSMISSION: Human-to-human transmission has been reported rarely in schools, daycares and hospitals Footnote 2. Nosocomial infections and blood transfusion related infections by this bacterium have been reported Footnote 2, Footnote 8. Fecal-oral transmission from animal-to-human or consumption of contaminated foods (raw pork products, undercooked pork, tofu and unpasteurized milk have been shown to be a source of outbreaks) and untreated water are also common modes of transmission Footnote 3-Footnote 5.
INCUBATION PERIOD: The incubation period for this bacterium is between 3-10 days Footnote 3.
RESERVOIR: Pigs are an important reservoir host although the bacterium has been found in several warm blooded animals, including farm animals and pets Footnote 2.
DRUG SUSCEPTIBILITY: Yersinia enterocolitica is susceptible to chloramphenicol, fluoroquinolones, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole Footnote 6. It is generally resistant to penicillin and its derivatives and to narrow spectrum cephalosporins Footnote 7, Footnote 10.
SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 2-5% phenol, 1% sodium hypochlorite, 70% ethanol, 4% formaldehyde, 2% glutaraldehyde, 2% peracetic acid, 3-6% hydrogen peroxide and 0.16% iodine Footnote 11.
PHYSICAL INACTIVATION: Bacteria are sensitive to moist heat (121 ºC for at least 12 minutes) and dry heat (170 ºC for 1 hour) Footnote 12.
SURVIVAL OUTSIDE HOST: The bacterium can survive 448 days in water between -4 and 8 ºC, and 10 days in water between 20 and 30 ºC Footnote 13. It can live up to 10 days in soil and cattle manure between -4 and 30 ºC Footnote 13.
Note: All diagnostic methods are not necessarily available in all countries.
FIRST AID/TREATMENT: Although infections by Yersinia enterocolitica are usually self limiting, antibiotic treatment is necessary for severe or complicated cases Footnote 5, Footnote 14. The antibiotics commonly used are gentamicin, cotrimoxazole, and ciprofloxacin Footnote 14. Surgery may be required to treat acute terminal ileitis Footnote 3.
LABORATORY-ACQUIRED INFECTIONS: None
PRIMARY HAZARDS: Accidental parenteral inoculation is always a risk when working with pathogens and ingestion of the infectious agent (via contaminated hands) is a hazard for laboratory personnel working with enteric pathogens Footnote 7.
SPECIAL HAZARDS: Contact with infected animals can be a risk Footnote 5.
RISK GROUP CLASSIFICATION: Risk group 2.
CONTAINMENT REQUIREMENTS: Containment Level 2 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials, animals, or cultures Footnote 15, Footnote 16.
PROTECTIVE CLOTHING: Lab coat. Gloves when direct skin contact with infected materials or animals is unavoidable. Eye protection must be used where there is a known or potential risk of exposure to splashes Footnote 15.
OTHER PRECAUTIONS: All procedures that may produce aerosols, or involve high concentrations or large volumes should be conducted in a biological safety cabinet (BSC). The use of needles, syringes, and other sharp objects should be strictly limited. Additional precautions should be considered with work involving animals or large scale activities Footnote 15.
SPILLS: Allow aerosols to settle and, wearing protective clothing, gently cover spill with paper towels and apply an appropriate disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up.
DISPOSAL: Decontaminate all wastes that contain or have come in contact with the infectious organism by autoclave, chemical disinfection, gamma irradiation, or incineration before disposing.
STORAGE: The infectious agent should be stored in leak-proof containers that are appropriately labelled.
REGULATORY INFORMATION: The import, transport, and use of pathogens in Canada is regulated under many regulatory bodies, including the Public Health Agency of Canada, Health Canada, Canadian Food Inspection Agency, Environment Canada, and Transport Canada. Users are responsible for ensuring they are compliant with all relevant acts, regulations, guidelines, and standards.
UPDATED: December 2011
PREPARED BY: Pathogen Regulation Directorate, Public Health Agency of Canada.
Although the information, opinions and recommendations contained in this Pathogen Safety Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.
Public Health Agency of Canada, 2011