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Morphology Obligate intracellular parasitic protozoa

Typically, non-pathogenic in immunocompetent adults but can be severe in immunocompromised people. Can cause acute infection, retinochoroiditis, encephalitis, and congenital infection.


Yes, from direct or indirect exposure of mucous membranes to oocysts of infected animals. Humans are intermediate hosts.

Health Hazards
Host Range Cats and other felines, humans, mammals, birds, flies and cockroaches.
Modes of Transmission  Ingestion of contaminated food, water, and contaminated milk. Inhalation of aerosols containing oocysts.
Signs and Symptoms  Symptoms include fever, rash, headache, lymphadenopathy, organomegaly, weight loss, weakness, pneumonia, and myalgia.
Infectious Dose Unknown
Incubation Period  Unknown
Medical Precautions/Treatment
Prophylaxis A treatment of sulfadiazine-pyrimethamine and folinic acid.
Vaccines None available.
Treatment Antibiotic therapy spiramycin, sulfadiazine, and folinic acid.
Surveillance Monitor for symptoms and confirm by positive serology for antibodies.
MSU Requirements  Report any exposures
Laboratory Hazards
Laboratory Acquired Infections (LAIs) 47 cases have been reported with one death.
 Sources May be present in blood, saliva, sputum, urine, milk, feces, and tissue. Cultures, frozen stocks, other samples described in IBC protocol.
Supplemental References
Canadian MSDS
NIH Guidelines
Risk Group & Containment Requirements
Risk Group 2

Agents that are associated with human disease which is rarely serious and for which preventive or therapeutic interventions are often available.

For all procedures involving suspected or known infectious specimen or cultures.
For all procedures utilizing infected animals.
Spill Procedures
Notify others working in the lab. Remove PPE and don new PPE. Cover area of the spill with absorbent material and add fresh 1:10 bleach:water. Allow 20 munutes (or as directed) of contact time. After 20 minutes, cleanup and dispose of materials.
  • Immediately notify all personnel in the lab and clear all personnel from the area. Remove any contaminated PPE/clothing and leave the lab. 
  • Secure the area by locking doors, posting signage and guarding the area to keep people out of the space. 
For assistance, contact MSU's Biosafety Officer (406-994-6733) or Safety and Risk Management (406-994-2711).
Exposure Procedures
Mucous membrane
Flush eyes, mouth, or nose for 5 minutes at eyewash station.
Other Exposures
Wash area with soap and water for 5 minutes.
Immediately report incident to supervisor, complete a First Report of Injury form, and submit to Safety and Risk Management.
Medical Follow-up
During business hours: Bridger Occupational Health 3406 Laramie Drive. Weekdays 8am -6pm.  Weekends 9am-5pm
After business hours: Bozeman Deaconess Hospital Emergency Room 915 Highland Blvd Bozeman, MT
Disinfection Susceptible to 1:10 bleach:water, 70 % ethanol and 10% formalin
Inactivation Inactivated by moist heat (15 minutes at 121° C) and dry heat (1 hour at 160-170° C), short wave UV, and gamma irradiation.
Survival Outside Host Can survive in moist soil or water for up to 18 months.
Personal Protective Equipment (PPE)
Minimum PPE Requirements
Lab coat, disposable gloves, safety glasses, closed toed shoes, long pants
Additional Precautions
Additioanl PPE may be required depending on lab specific SOPs and IBC Protocol.