Mycobacterium bovis/BCG Agent Information Sheet

Boston University
Research Occupational Health Program (ROHP)
617-358-7647

Agent

Mycobacterium bovis (M. bovis) is part of the of mycobacterium tuberculosis complex. It is an acid fast, gram positive bacilli, that is non-spore forming, non-motile, slightly curved, aerobic and slow-growing.

Disease/Infection

Untreated M. bovis may progress to gastrointestinal or pulmonary disease.

Pathogenicity

Mycobacterium bovis infections are more likely to present at an extra pulmonary site.

  • Special Populations at Risk
    Immunocompromised

Biosafety Information

Risk Group/BSL
Wild type M. bovis is RG-3 BSL3
M. bovis BCG vaccine strain
Risk Group 2
Biosafety Level 2 Practices

Modes of Transmission
Portal entry is the lung; pathogen is carried as airborne particles.

Transmission
Skin Exposure (Needlestick, bite, or scratch):Yes
Mucous Membrane Splash to Eye(s), Nose or Mouth:Direct skin contact with M. Bovis.
Inhalation:Through droplet nuclei
Ingestion:Yes

Host Range / Reservoir
Primarily humans, cattle, primates, other animals (rodents).

Symptoms
Initial infection usually unnoticed, tuberculin sensitivity appears in a few weeks. Latent infection may progress to pulmonary tuberculosis (fatigue, fever, cough, chest pain, hemoptysis fibrosis, cavitation) or extra pulmonary involvement (miliary, meningeal) by lymphohematogenous dissemination; infection with bovine bacillus rare; drug resistant strains can cause irreversible damage in the lungs.

Symptoms generally appear months to years after infection with M. bovis, but some people may never show signs of illness. General symptoms of M. bovis may include fever, night sweats, and weight loss. Other symptoms may manifest themselves depending on the part of the body affected by the disease: disease in the lungs may be associated with a cough; lymph node disease may cause swelling in the neck; and gastrointestinal disease may cause abdominal pain and swelling, and diarrhea. In rare instances, a person may die if the disease is left untreated.

Incubation period
From infection to primary lesion or significant tuberculin reaction – 4 to 12 weeks; risk of progressive pulmonary or extra pulmonary tuberculosis is greatest within 1 to 2 years after infection; may persist for lifetime as latent infection.

Viability
M. bovis has greater resistant to disinfectants and requires longer contact times for most disinfectants to be effective; 5% phenol, 1% sodium hypochlorite (only if low organic matter and longer contact times), iodine solutions (high concentration of available iodine required), glutaraldehyde and formaldehyde (longer contact time) are effective.

Survival Outside Host
Guinea pig carcasses – 49 days; carpet – up to 70 days; dust – 90 to 120 days; cockroaches – 40 days; manure 45 days; paper book – 105 days; sputum (cool, dark location) – 6 to 8 months; clothing – 45 days.

Information for Lab Workers

Laboratory PPE

PPE Wild type agent
Personal protective equipment includes but is not limited to gowns with tight wrists and ties in back, disposable gloves, combination safety glass and mask or a face shield. Facilities for washing and changing clothing after work should be available.

PPE BCG vaccine strain
Personal protective equipment includes but is not limited to laboratory coats or gowns, disposable gloves, and safety glasses.

Containment

Containment Wild Type Agent
Research should be conducted using Biosafety Level 3 practices, equipment, and facility design. Gloves and gowns should be worn when handling infected laboratory animals and when there is the likelihood of direct skin contact with infectious materials. Animal studies may be performed at ABSL-3. BSL-3 practices, containment equipment, and facilities are recommended for activities using clinical materials and diagnostic quantities of infectious cultures.

Containment BCG Vaccine Strain
BSL-2 practices and procedures, containment equipment, and facilities are required for non-aerosol-producing manipulations of clinical specimens such as preparation of acid-fast smears. All aerosol-generating activities must be conducted in a BSC.

In Case of Exposure/Disease

  • For injuries in the lab which are major medical emergencies (heart attacks, seizures, etc…):
    • Medical Campus: call or have a coworker call the Control Center at 617-414–4144.
    • Charles River Campus: call or have a coworker call campus security at 617-353-2121.
      You will be referred to or transported to the appropriate health care location by the emergency response team.
  • For lab exposures (needle sticks, bite, cut, scratch, splash, etc…) involving animals or infectious agents, or for unexplained symptoms or illness call the ROHP 24/7 hour number (1-617-358-ROHP (7647); or, 8-ROHP (7647) if calling from an on-campus location) to be connected with the BU Research Occupational Health Program (ROHP) medical officer. ROHP will refer you to the appropriate health care location.
  • Under any of these scenarios, always inform the physician of your work in the laboratory and the agent(s) that you work with.
  • Provide the wallet-size agent ID card to the physician.

Vaccination

Licensed attenuated live vaccine (BCG) is available, but not routinely carried out in US.

Information for First Responders/Medical Personnel

Public Health Issues

Diagnosis/Surveillance

In previously negative skin test personnel, a tuberculin skin test should be obtained, chest x-ray done for positive TST. In patients suspected of active disease, AFB smear and culture of clinical tissue specimen or sputum can aid in diagnosis as can PCR based technologies.

First Aid/Post Exposure Prophylaxis

Perform one of the following actions:

Skin Exposure (Needlestick or scratch):Immediately go to the sink and thoroughly wash the wound with soap and water for 15 minutes. Decontaminate any exposed skin surfaces with iodine. Allow to bleed freely.
Mucous Membrane Splash to Eye(s), Nose or Mouth:Exposure should be irrigated vigorously.
Splash Affecting Garments:Remove garments that may have become soiled or contaminated and place them in a double red plastic bag.
Inhalation:Testing will be done.

Preventive treatment with INH (risk of hepatitis for those over 35 years old) for 9 months.

Treatment

Combination antibiotic therapy, similar to M. Tuberculosis, consists isoniazid, rifampin, ethambutol, pyrazinamide. M Bovis has inherent resistance to pyrazinamide. Treatment is adjusted based on culture and susceptibility results and with the aid of an infectious diseases specialist.

References

Biosafety in Microbiological and Biomedical Laboratories; Deborah E. Wilson, DrPH, CBSP Director Division of Occupational Health and Safety National Institutes of Health Bethesda, Maryland L. Casey Chosewood, M.D. Director Office of Health and Safety Centers for Disease Control and Prevention Atlanta, Georgia; US Government Printing Office, Washington DC. 5th Edition; 2007

Control of Communicable Diseases Manual. David L. Heymann. Washington DC, USA: American Public Health Association Press, 19th edition, 2008

NYC Mycobacterium bovis (M. bovis) Fact Sheet http://www1.nyc.gov/site/doh/health/health-topics/tuberculosis.page

Public Health Agency of Canada, M. Bovis Fact Sheet; http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/tuber-eng.php

Bovine Tuberculosis; Institute for International Cooperation in Animal Biologics; Iowa State University; http://www.cfsph.iastate.edu/Factsheets/pdfs/bovine_tuberculosis.pdf

Communicable Infection Disease; 42:1756.2006

Communicable Infection Disease; 47:1768:2008

Revised: 7/20/2012

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