Pathogen Safety Data Sheets: Infectious Substances – Streptococcus pyogenes



NAME: Streptococcus pyogenes

SYNONYM OR CROSS REFERENCE: Group A (β-hemolytic) streptocci (GAS), streptococcal sore throat, strep throat, pharyngitis, scarlet fever, impetigo, erysipelas, puerperal fever, necrotizing fasciitis, toxic shock syndrome, septicaemia, acute rheumatic fever, acute post-streptococcal glomerulonephritis, gas gangrene

CHARACTERISTICS: Streptococcus pyogenes is an aerobic, gram-positive extracellular bacterium (1, 2). It is made up of non-motile, non-sporing cocci that are less then 2 µm in length and that form chains and large colonies greater then 0.5 mm in size (3, 4). It has a β-hemolytic growth pattern on blood agar and there are over 60 different strains of the bacterium (5, 6)


PATHOGENICITY/TOXICITY: This bacterium is responsible for a wide array of infections (7, 8). It can cause streptococcal sore throat which is characterized by fever, enlarged tonsils, tonsillar exudate, sensitive cervical lymph nodes and malaise (6, 9). If untreated, strep throat can last 7-10 days (9). Scarlet fever (pink-red rash and fever) as well as impetigo (infection of the superficial layers of skin) and pneumonia are also caused by this bacterium (3, 6, 7, 10). Septicaemia, otitis media, mastitis, sepsis, cellulitis, erysipelas, myositis, osteomyelitis, septic arthritis, meningitis, endocarditis, pericarditis, and neonatal infections are all less common infections due to S. pyogenes (3, 6, 7). Streptococcal toxic shock syndrome, acute rheumatic fever (joint inflammation, carditis and CNS complications), post-streptococcal glomerulonephritis (inflammation, hematuriia, fever, edema, hypertension, urinary sediment abnormalties and severe kidney pain) and necrotizing fasciitis (rapid and progressive infection of subcutaneous tissue, massive systematic inflammation, hemorrhagic bullae, crepitus and tissue destruction) are some of the more serious complications involving S. pyogenes infections (1, 6-8). There are at least 517,000 deaths globally each year due to severe S. pyogenes infections and rheumatic fever disease alone causes 233,000 deaths (8). 1,800 invasive S. pyogenes disease-related deaths are reported in the USA yearly, necrotizing fasciitis kills about 30% of patients and streptococcal toxic shock syndrome has a mortality rate of 30-70% (3, 11, 12).

EPIDEMIOLOGY: Different clinical manifestations of this bacterium are more common in different parts of the world. Streptococccal pharyngitits is predominant in temperate areas and peaks in late winter and early spring (5, 9). There are 616 million cases of pharyngitis caused by S. pyogenes world-wide each year (5, 8). 15-20% of school-aged children has S. pyogenes in its carrier form in their throats and are more at risk of having the disease (5, 9). Impetigo is more common with children in warm humid climates and there are 111 million reported cases world-wide each year (5). There are 115.6 million cases of rheumatic heart disease yearly and at least 18.1 million cases of invasive infections, predominantly in older populations (3, 8). Post-streptococcal glomerulonephritis is seasonal and is more common in children, young adults and males (1). Crowding and poor hygiene increase the chance of an outbreak of GAS infections (1).

HOST RANGE: S. pyogenes is an exclusively human pathogen (5, 7).


MODE OF TRANSMISSION: Transmission via respiratory droplets, hand contact with nasal discharge and skin contact with impetigo lesions are the most important modes of transmission (5, 9, 13). The pathogen can be found in its carrier state in the anus, vagina, skin and pharynx and contact with these surfaces can spread the infection (5, 14, 15) The bacterium can be spread to cattle and then back to humans through raw milk as well as through contaminated food sources (salads, milk, eggs); however, cattle do not contract the disease (16-18). Necrotizing fasciitis is usually because of contamination of skin lesions or wounds with the infectious agent (12).

INCUBATION PERIOD: The incubation period is usually 1-3 days (9).

COMMUNICABILITY: If untreated, patients with streptococcal pharyngitis are infective during the acute phase of the illness, usually 7-10 days, and for one week afterwards; however, if antibiotics are used, the infective period is reduced to 24 hours (9). The bacterium can remain in the body in its carrier state without causing illness in the host for weeks or months and is transmissible in this state (5).


RESERVOIR: Humans are primary reservoir for this bacterium (5, 7), although cattle can also act as a reservoir (16-18).

ZOONOSIS: Cows infected by humans are intermediate hosts and can pass the bacterium in their milk, which, if consumed unpasteurized, can infect other humans (16).



DRUG SUSCEPTIBILITY: S. pyogenes infections are susceptible to a variety of drugs: β-lactams such as penicillin, as well as erythromycin, clindamycin, imipenem, rifampin, vanomycin, macrolides and lincomycin; however, certain strains of the bacterium have been found to resistant to macrolides, lincomycin, chloramphenicol, tetracyclines and cotrimoxazole (5, 7, 19, 20).

SUSCEPTIBILITY TO DISINFECTANTS: This bacteria is susceptible to 1% sodium hypochlorite, 4% formaldehyde, 2% glutaraldehyde, 70% ethanol, 70% propanol, 2% peracetic acid, 3-6% hydrogen peroxide and 0,16% iodine (2).

PHYSICAL INACTIVATION: Bacteria are susceptible to moist heat (121 ºC for at least 15 minutes) and dry heat (170 ºC for at least 1 hour) (21).

SURVIVAL OUTSIDE HOST: The bacterium can survive on a dry surface for 3 days to 6.5 months (22). It has been found to survive in ice cream (18 days), raw and pasteurized milk at 15-37 ºC (96 hrs), room temperature butter (48 hrs), and neutralized butter (12-17 days) (17). GAS has been found to last several days in cold salads at room temperature (18).


SURVEILLANCE: Monitor for symptoms. Confirm infection by bacteriological and serological testing, latex bead agglutination, fluorescent antibody staining or ELISA (6).

Note: All diagnostic methods are not necessarily available in all countries.

FIRST AID/TREATMENT: Appropriate antibiotic treatment is necessary for a S. pyogenes infection. Penicillin is used for respiratory tract infections (pharyngitis) and macrolides or lincosamides are used if there are allergies (5, 6). Clindamycin may be used in cases of necrotizing fasciitis and surgical debridement of the affected area is necessary (2, 5).


PROPHYLAXIS: Administering penicillin to carriers has been shown to reduce the number of people infected during an outbreak of streptococcal sore throat (18).


LABORATORY-ACQUIRED INFECTIONS: 78 laboratory-acquired infections by streptococcal agents have been reported as of 1983 (2).

SOURCES/SPECIMENS: Respiratory specimens, skin lesions, blood, sputum and wound exudates contain the infectious agent (5, 13, 23).

PRIMARY HAZARDS: Inhalation of infectious aerosols and contamination of mucocutaneous lesions are the primary hazards associated with working with this pathogen (1, 2, 10)




CONTAINMENT REQUIREMENTS: Containment Level 2 facilities, equipment, and operational practices for work involving infectious or potentially infectious material, animals, or cultures.

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 (25).

OTHER PRECAUTIONS: All procedures that may produce aerosols, or involve high concentrations or large volumes should be conducted in a biological safety cabinet (BSC) (25). 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 (25).


SPILLS: Allow aerosols to settle and, wearing protective clothing, gently cover spill with paper towels and apply appropriate disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up (25).

DISPOSAL: Decontaminate all wastes before disposal by incineration, chemical disinfection or steam sterilization (25).

STORAGE: The infectious agent should be stored in a sealed and identified container (25).


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: July 2010

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.

Copyright ©

Public Health Agency of Canada, 2010



  1. Cunningham, M. W. (2008). Pathogenesis of group A streptococcal infections and their sequelae. Advances in Experimental Medicine and Biology, 609, 29-42. doi:10.1007/978-0-387-73960-1_3
  2. Collins, C. H., & Kennedy, D. A. (Eds.). (1983). Laboratory-acquired Infections (4th ed.). Oxford: Butterworth-Heinermann.
  3. Murray, P. R., Baron, E. J., Jorgensen, J. H., Landry, M. L., & Pfaller, M. A. (Eds.). (2007). Manual of Clinical Microbiology (9th ed.). Washington: ASM Press.
  4. Kilian, M. (1998). Streptococcus and Lactobacillus. In A. Balows, & B. I. Duerden (Eds.), Topley & Wilson's microbiology and microbial infections (9th ed., pp. 633-668). London: Arnold.
  5. Bessen, D. E. (2009). Population biology of the human restricted pathogen, Streptococcus pyogenes. Infection, Genetics and Evolution : Journal of Molecular Epidemiology and Evolutionary Genetics in Infectious Diseases, 9(4), 581-593. doi:10.1016/j.meegid.2009.03.002
  6. Brock, T. D., Madigan, M. T., Martinko, J. M., & Parker, J. (2000). Biology of Microorganisms (9th ed.). New Jersey, USA: Prentice-Hall, Inc.
  7. Cohen, R., Aujard, Y., Bidet, P., Bourrillon, A., Bingen, E., Foucaud, P., Francois, M., Garnier, J. M., Gendrel, D., Guillot, M., Hau, I., Olivier, C., Quinet, B., & Raymond, J. (2005). Streptococcus pyogenes an emerging pathogen. [Le streptocoque du groupe A. Un pathogene majeur pour la prochaine decennie?] Archives De Pediatrie : Organe Officiel De La Societe Francaise De Pediatrie, 12(7), 1065-1067. doi:10.1016/j.arcped.2005.01.021
  8. Carapetis, J. R., Steer, A. C., Mulholland, E. K., & Weber, M. (2005). The global burden of group A streptococcal diseases. The Lancet Infectious Diseases, 5(11), 685-694. doi:10.1016/S1473-3099(05)70267-X
  9. Vincent, M. T., Celestin, N., & Hussain, A. N. (2004). Pharyngitis. American Family Physician, 69(6), 1465-1470.
  10. Fleming D & Hunt D (Ed.). (2006). Biological Safety Principles and Practices (4th ed.). Washington: ASM Press.
  11. Stevens, D. L. (1995). Streptococcal toxic-shock syndrome: spectrum of disease, pathogenesis, and new concepts in treatment. Emerging Infectious Diseases, 1(3), 69-78.
  12. Torralba, K. D., & Quismorio, F. P.,Jr. (2009). Soft tissue infections. Rheumatic Diseases Clinics of North America, 35(1), 45-62. doi:10.1016/j.rdc.2009.03.002
  13. Ryan, K. J., & Ray, C. G. (Eds.). (2004.). Sherris Medical Microbiology: An Introduction to Infectious Disease. (Fourth Edition. ed.). New York.: McGraw-Hill.
  14. Rasi, A., & Pour-Heidari, N. (2009). Association between plaque-type psoriasis and perianal streptococcal cellulitis and review of the literature. Archives of Iranian Medicine, 12(6), 591-594.
  15. Mead, P. B., & Winn, W. C. (2000). Vaginal-rectal colonization with group A streptococci in late pregnancy. Infectious Diseases in Obstetrics and Gynecology, 8(5-6), 217-219. doi:10.1155/S1064744900000302
  16. Henningsen, E. J., & Ernst, J. (1938). Milk epidemic of angina, originating from a cow with mastitis and due to Streptococcus pyogenes (Lancefield group A). The Journal of Hygiene, 38(3), 384-391.
  17. International Commission on Microbiological Specifications for Foods. (1996).
    Microbiological specifications of food pathogens
  18. Katzenell, U., Shemer, J., & Bar-Dayan, Y. (2001). Streptococcal contamination of food: an unusual cause of epidemic pharyngitis. Epidemiology and Infection, 127(2), 179-184.
  19. Bernaldo de Quiros, J. C., Moreno, S., Cercenado, E., Diaz, D., Berenguer, J., Miralles, P., Catalan, P., & Bouza, E. (1997). Group A streptococcal bacteremia. A 10-year prospective study. Medicine, 76(4), 238-248.
  20. Nakae, M., Murai, T., Kaneko, Y., & Mitsuhashi, S. (1977). Drug resistance in Streptococcus pyogenes isolated in Japan. Antimicrobial Agents and Chemotherapy, 12(3), 427-428.
  21. Joslyn, L. J. (2001). Sterilization by Heat. In S. S. Block (Ed.), Disinfection, Sterilization, and Preservation (5th ed., pp. 695). Philadelphia: Lippincott Williams & Wilkins.
  22. Kramer, A., Schwebke, I., & Kampf, G. (2006). How long do nosocomial pathogens persist on inanimate surfaces? A systematic review. BMC Infectious Diseases, 6, 130. doi:10.1186/1471-2334-6-130
  23. Lacy, M. D., & Horn, K. (2009). Nosocomial transmission of invasive group a streptococcus from patient to health care worker. Clinical Infectious Diseases : An Official Publication of the Infectious Diseases Society of America, 49(3), 354-357. doi:10.1086/599832
  24. Human pathogens and toxins act. S.C. 2009, c. 24, Second Session, Fortieth Parliament, 57-58 Elizabeth II, 2009. (2009).
  25. Public Health Agency of Canada. (2004). In Best M., Graham M. L., Leitner R., Ouellette M. and Ugwu K. (Eds.), Laboratory Biosafety Guidelines (3rd ed.). Canada: Public Health Agency of Canada.
Report a problem or mistake on this page
Please select all that apply:

Privacy statement

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: