NAME: Streptococcus salivarius.
CHARACTERISTICS: A member of the Salivarius group of viridans streptococci Footnote 7, Footnote 8. S. salivarius is an α-haemolytic streptococci Footnote 9, existing as a commensal of the oral cavity Footnote 1, Footnote 3, Footnote 5, Footnote 8, Footnote 10-Footnote 12, skin Footnote 4, Footnote 5, Footnote 9, Footnote 10, Footnote 12, gastrointestinal Footnote 3, Footnote 5, Footnote 10-Footnote 12, oropharynx Footnote 4, Footnote 13, and genitourinary tracts Footnote 3, Footnote 8, Footnote 10, Footnote 12. Streptococci, in general, are spherical or ovoid in shape and typically exist in chains or pairs Footnote 11. They are gram positive, non-motile, non-sporing, catalase negative, and facultatively anaerobic.
PATHOGENICITY/TOXICITY: S. salivarius has been associated with a variety of infections Footnote 14. The most common reports refer to meningitis Footnote 3-Footnote 5, Footnote 9, Footnote 12, Footnote 13, and bacteraemia Footnote 6, Footnote 15. Other cases include pericarditis, spontaneous bacterial peritonitis, acute jejunitis, pancreatic abscess, multimicrobial endocarditis, early neonatal sepsis, sinusitis, endophthalmitits, bullous impetigo and femoral osteitis Footnote 14. It must be noted, however, that although S. salivarius frequently enter the bloodstream, infections with S. salivarius are rare due to their low virulence Footnote 1, Footnote 3, Footnote 5, Footnote 16. Many patients with S. salivarius bacteraemia have predisposing local factors such as mucosal disruption and/or serious underlying diseases, such as malignancy or liver cirrhosis Footnote 16.
INFECTIOUS DOSE: Unknown.
MODE OF TRANSMISSION: S. salivarius is part of the normal human flora. It can be transmitted by direct contamination of sterile body fluid, for example, contamination of cerebrospinal fluid following epidural anaesthesia or lumbar puncture Footnote 4, Footnote 5, Footnote 9, Footnote 10, Footnote 14, due to contaminated equipment, by migration of the organism from the patient’s skin along the outer surface of the catheter Footnote 4, Footnote 5, Footnote 9, or via air droplets originating from the oropharynx Footnote 10. S. salivarius in the oral cavity can also enter the bloodstream (bacteraemia) following endoscopy and associated therapeutic interventions Footnote 5, Footnote 14-Footnote 16. Once the organism is in the bloodstream it can seed various anatomical sites (including the meninges and the cerebrospinal fluid) Footnote 14.
INCUBATION PERIOD: Unknown.
COMMUNICABILITY: Many suspected cases of human-to-human transmission have been recorded Footnote 4, Footnote 5, Footnote 9, Footnote 10, Footnote 12; however, very few cases have been confirmed. So far, only one report was able to unambiguously identify the source of infection, which was from the throat of a doctor to a patient during a lumbar puncture procedure Footnote 13.
DRUG SUSCEPTIBILITY: Sensitive to various antibiotics, including ciprofloxacin, levofloxacin, metronidazole Footnote 8, penicillin Footnote 2, Footnote 10, Footnote 13, amoxicillin Footnote 2, Footnote 5, Footnote 12, Footnote 16, ceftriaxone Footnote 2-Footnote 5, Footnote 14, clindamycin, rifampicin Footnote 2, gentamycin Footnote 5, cefuroxime, moxifloxacin Footnote 16, ceftoxime Footnote 1, and vancomycin Footnote 1, Footnote 2, Footnote 4, Footnote 12, Footnote 14. Certain strains of S. salivarius have shown partial resistance to penicillin Footnote 1, Footnote 4, Footnote 16, ceftriaxone Footnote 4, erythromycin Footnote 1, Footnote 2, Footnote 16, and meropenem Footnote 1.
SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 5.25% sodium hypochlorite, and cresophene (30% paramonochlorophenol, 5% thymol, 0.1% dexamethasone), 21% alcohol, and 2.0% chlorohexidine Footnote 17.
PHYSICAL INACTIVATION: Streptococcal species are inactivated at low pH Footnote 15.
SURVIVAL OUTSIDE HOST: Unknown. Studies in the 1930s and 1940s suggest that S. salivarius can survive on drinking glass rims and utensils for at least a couple of days Footnote 18, Footnote 19; however, genetic identification was not available at this time, and it is unknown whether species-specific identification was possible.
SURVEILLANCE: Monitor for symptoms. Confirm infection using gram-stain Footnote 4, Footnote 5, Footnote 10, followed by isolation of the organism from blood Footnote 3, Footnote 5, Footnote 6, Footnote 8, Footnote 16, Footnote 17 or cerebrospinal fluid culture Footnote 3-Footnote 5, Footnote 9, Footnote 10, Footnote 12, Footnote 13. PCR has also been used to identify S. salivarius in clinical samples Footnote 13.
Note: All diagnostic methods are not necessarily available in all countries.
FIRST AID/TREATMENT: Antibiotic therapy Footnote 3-Footnote 5, Footnote 8-Footnote 10, Footnote 12, Footnote 14, Footnote 16, typically with ceftriaxone Footnote 4, Footnote 5, Footnote 12, Footnote 14, Footnote 16, amoxicillin Footnote 12, Footnote 16, and/or vancomycin Footnote 4, Footnote 5, Footnote 14, Footnote 16. Treatment is delivered depending on the manifestation of the infection, for example patients suffering from meningitis due to S. salivarius may require mechanical ventilation Footnote 4.
IMMUNIZATION: None currently available.
LABORATORY-ACQUIRED INFECTIONS: No specific laboratory-acquired infections with S. salivarius have been reported; however, there were 78 recorded cases of streptococcal infection (species not specified), with 4 deaths up to 1976 Footnote 20.
SOURCES/SPECIMENS: Blood Footnote 6, Footnote 8, Footnote 14, Footnote 16, Footnote 17, peritoneal fluid Footnote 8, cerebrospinal fluid Footnote 3-Footnote 5, Footnote 10, Footnote 12, Footnote 14, and oropharyngeal secretions Footnote 4, Footnote 10.
SPECIAL HAZARDS: None.
RISK GROUP CLASSIFICATION: Risk Group 2 Footnote 21.
CONTAINMENT REQUIREMENTS: Containment Level 2 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials, animals, or cultures Footnote 22.
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 22.
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 22.
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 Footnote 22.
DISPOSAL: Decontaminate all wastes that contain or have come in contact with the infectious organism before disposing by autoclave, chemical disinfection, gamma irradiation, or incineration Footnote 22.
STORAGE: The infectious agent should be stored in leak-proof containers that are appropriately labelled Footnote 22.
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