Skip to main content

Leptospira spp. Biological Agent Reference Sheet (BARS)

Updated December 1, 2023
Disclaimer: Risk group, biosafety level, and all other precautions noted here are subject to change after a risk assessment by EHS.


Agent Type Risk Group Biosafety Level Animal Housing Biosafety Level
Bacteria – Spirochete RG-2 BSL-2 ABSL-2

Agent Characteristics 

Risk Group: RG-2 associated with human disease, rarely serious; preventive or therapeutic interventions often available.

Agent Type: Bacteria – Spirochete 

DescriptionLeptospira interrogans (serovars Canicola, Hardjo, Icterohaemorrhagiae, Pomona, Sejroe, and others) is a gram-negative spirochete which infects various domestic and wild animals. Infective bacteria are shed via the urine. Humans are infected when urine or contaminated materials enter the body through broken skin or mucosa. Primary organs targeted include the liver, kidneys, lungs, and central nervous system. Mode of tissue damage is unknown. 

Host Range: Wide range – rodents, cattle, horses, sheep, goat, pigs, dogs, and humans are more common

Host Shedding: Blood, Feces, Saliva, Urine                              

Route of Exposure to Humans: Aerosol/Inhalation, Direct Contact, Mucous Membranes, Animal Bites, Contaminated Items, Ingestion, Percutaneous, Broken Skin

Infectious Dose: Unknown                                  Incubation Period: 7-12 days up to 30 days 

Health Hazards

Signs and symptoms of infection may include:

  • Flu-like symptoms (i.e. fever, headache, dehydration, weight loss, lethargy)
  • Respiratory symptoms (i.e. coughing, sneezing)
  • Conjunctival suffusion, ataxia, skin rash. 

Immunizations: None available                           Prophylaxis*: Treated orally with antibiotics

*Formal medical advice is obtained during medical consultations with Cornell Health or primary healthcare provider as needed.

Agent Viability 

Survival Outside Host Disinfection Inactivation

Leptospira spp. are excreted in urine into the environment, where they can survive or several months, depending on favorable environmental conditions.

1:10 Bleach Dilution

Leptospires are inactivated easily by routine cleaning. Avoid high-pressure washing equipment in areas contaminated with Leptospira spp. as it may aerosolize urine.

For more guidance on disinfection see: disinfectant selection.

Laboratory Hazards 

  • High energy-creating activities (centrifugation, sonication, high pressure systems, vortexing, tube cap popping)
  • Handling of sharps (needles, scalpels, microtome blades, broken glass, etc.)
  • Splash/droplet-creating activities (shaking incubators, liquid culturing, mechanical pipetting)
  • Equipment contamination
  • Exposed skin/uncovered wounds

Laboratory Acquired Infection (LAI) History:  67 laboratory-associated cases of leptospirosis and 10 deaths. Infection related to occupational exposure usually is caused by accidental parenteral inoculation, direct or indirect contact with cultures or infected materials (especially urine), and animal bites.

Laboratory Handling Guidelines 

Laboratory Biosafety Level (BSL): BSL-2


Lab Engineering Controls Personal Protective Equipment
  • Eye Protection
  • Single gloves
  • Snap-front lab coat with cinch cuffs
  • Additional mucous membrane protection-recommended for aerosol producing activities

Waste Management: Regulated Medical Waste (RMW)

Shipping Guidance: Refer to EHS Biological Materials Shipping 

Animal Vivarium Guidance

Animal Housing Biosafety Level (ABSL): ABSL-2

Animal Biosecurity: Experimental animals are housed separately       

Perform Inoculations: Cage Changing Station, Biosafety Cabinet

Change CagesBenchtop, In a Biosafety Cabinet, Cage Changing Station

Exposure and Spill Procedures 

Mucous Membranes: Flush eyes, mouth, or nose for 15 minutes at an eyewash station. See: responding to exposures.

Other Exposures: Wash with soap and water for 15 minutes (open wounds, sores, etc.) or a minimum of 20 seconds for areas with intact skin. See: responding to exposures.

Small Spills: Notify others working in the lab. Evacuate area and allow 30 minutes for aerosols to settle. Don appropriate PPE. Cover area of the spill with paper towels and apply disinfectant, working from the perimeter toward the center. Allow 30 minutes of contact time before disposal and cleanup of spill materials. See:  spill cleanup

Large Spills: Request assistance from the EHS Spill Team by calling CUPD dispatch. Call 911 from a campus phone or 607-255-1111 from a mobile phone.

Incident Reporting: Immediately report the incident to supervisor and complete the EHS online injury/illness report as soon as possible.

Medical Follow-Up:

  • For students, seek medical attention at Cornell Health or local primary care provider. Call Cornell Health at 607-255-5155 (24-hour phone consultation line) or a local urgent care. 
  • For faculty and staff, seek medical evaluation with a local primary care provider or urgent care. Cornell Health does not see employees for post-exposure care. 
  • Emergencies: Call 911 from a campus phone or 607-255-1111 from a mobile phone. 
Cornell EHS would like to thank Emory University for the use of their Biological Agent Reference Sheet (BARS) format and some content. 

More Information


  1. US Department of Health and Human Services, (U.S.), C. for D. C. and P., & 2009, N. I. of H. (U. S. )A.-P. Y.-. (2009). Biosafety in microbiological and biomedical laboratories (5th ed.). [Washington D.C.]: U.S. Dept. of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institutes of Health. Retrieved from 
  2. Saito, M. et al. Comparative Analysis of Leptospira Strains Isolated from Environmental Soil and Water in the Philippines and Japan. Appl. Environ. Microbiol. 79, 601–609 (2013).
  3. Sewell, D. L. Laboratory-Associated Infections and Biosafety. Clin. Microbiol. Rev. 8, 389–405 (1995)