Related Experiment Video
Updated: Jun 6, 2026
Intradermal Inoculation of Mycobacterium avium in the Mouse Ear
Published on: July 3, 2025
Accidental infection of veterinary personnel with Mycobacterium tuberculosis at necropsy: a case study
H Posthaus1, T Bodmer, L Alves
1Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Switzerland. horst.posthaus@itpa.unibe.ch
Abstract:
Mycobacterium tuberculosis is the main cause of human tuberculosis. Infection in companion animals is mainly acquired from close contact to a diseased human patient and hence rarely diagnosed in countries with low tuberculosis incidence rates. Therefore the general awareness of the disease might be low. Here we report the potential risk of infection for veterinary personnel with M. tuberculosis during the clinical and pathological examination of a dog with unexpected disseminated tuberculosis. The dog had presented with symptoms of a central nervous system disease; rapid deterioration prevented a complete clinical workup, however. Post-mortem examination revealed systemic mycobacteriosis, and M. tuberculosis was identified by PCR amplification of DNA extracts from paraffin-embedded tissue sections and spoligotyping. Contact investigations among the owners and veterinary personnel using an IFN-γ release assay indicated that the index dog did not infect humans during its lifetime. Serological and IFN-γ release assay results of one of two cats in direct contact with the index dog, however, suggested that transmission of M. tuberculosis might have occurred. Importantly, all three pathologists performing the necropsy on the dog tested positive. Accidental infection was most likely due to inhalation of M. tuberculosis containing aerosols created by using an electric saw to open the brain cavity. As a consequence routine necropsy procedures have been adapted and a disease surveillance program, including tuberculosis, has been initiated. Our results highlight the importance of disease awareness and timely diagnosis of zoonotic infectious agents in optimizing work safety for veterinary personnel.
Insights
Veterinary staff were potentially exposed to tuberculosis during a dog necropsy. Although the dog did not infect its owners, three pathologists contracted tuberculosis, highlighting occupational risks and the need for enhanced safety protocols.
Area of Science:
- Veterinary Medicine
- Zoonotic Diseases
- Infectious Disease Epidemiology
Background:
- Mycobacterium tuberculosis causes human tuberculosis and can infect companion animals through human contact.
- Zoonotic tuberculosis transmission is rare in low-incidence countries, potentially leading to low awareness among veterinary professionals.
- Disseminated tuberculosis in companion animals presents diagnostic challenges and potential occupational risks.
Purpose of the Study:
- To report a case of potential occupational M. tuberculosis infection in veterinary personnel during a dog necropsy.
- To assess M. tuberculosis transmission risk from an infected dog to humans and other animals.
- To emphasize the importance of disease awareness and safety protocols in veterinary practice.
Main Methods:
- Clinical and pathological examination of a dog with suspected central nervous system disease.
- Identification of M. tuberculosis using PCR and spoligotyping on tissue samples.
- Contact tracing using IFN-γ release assays for owners, cats, and veterinary personnel.
Main Results:
- M. tuberculosis was identified in a dog with disseminated systemic mycobacteriosis.
- No human infections were detected among owners; one cat showed possible M. tuberculosis infection.
- All three pathologists performing the necropsy tested positive for M. tuberculosis, likely from aerosol exposure during brain cavity opening.
Conclusions:
- Veterinary personnel face occupational risks of M. tuberculosis infection, particularly during necropsies involving aerosol-generating procedures.
- Enhanced disease surveillance and adapted necropsy procedures are crucial for veterinary personnel safety.
- Timely diagnosis and awareness of zoonotic diseases are essential for optimizing occupational health in veterinary settings.
Related Concept Videos
01:29Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
01:23Tuberculosis
01:28Pulmonary Tuberculosis II
Here is a detailed explanation of its pathophysiology:
Transmission: The process begins when a person inhales droplet nuclei containing M. tuberculosis. These are typically released into the air when an individual with pulmonary or...