What is the Difference Between Mycobacterium Tuberculosis and Mycobacterium Bovis?

Mycobacterium tuberculosis (M. tuberculosis) and Mycobacterium bovis (M. bovis) are both members of the Mycobacterium tuberculosis complex (MTC) and are responsible for causing tuberculosis (TB) in humans and animals, respectively. While both species are closely related, there are some key differences between them:

1. Host preference: M. tuberculosis primarily affects humans, while M. bovis is more commonly found in animals such as cattle, bison, elk, deer, pigs, cats, dogs, goats, and badgers. However, M. bovis can also cause TB in humans.
2. Symptoms: M. bovis is more often an intestinal disease, whereas M. tuberculosis more commonly affects the lungs.
3. Prevalence in humans: M. bovis causes a relatively small proportion, less than 2%, of the total number of TB cases in the United States.
4. Differentiation: A rapid assay for differentiation between M. bovis and M. tuberculosis has been developed using high-resolution melt curve analysis, which relies on single-nucleotide polymorphisms (SNPs) in the region of differences 1 (RD1).
5. Treatment: M. bovis is usually resistant to one of the antibiotics, pyrazinamide, typically used to treat TB disease. However, resistance to just pyrazinamide does not usually affect the treatment of M. bovis in humans.
6. Vaccination: Both M. tuberculosis and M. bovis can be used in vaccines. For example, Bacillus Calmette-Guérin (BCG) is an attenuated strain of M. bovis used as a vaccine against tuberculosis.

Comparative Table: Mycobacterium Tuberculosis vs Mycobacterium Bovis

Mycobacterium tuberculosis and Mycobacterium bovis are closely related pathogens responsible for human and bovine tuberculosis, respectively. Here is a table highlighting the differences between the two:

Despite their high sequence identity, variations in gene expression may be involved in differentiating the two pathogens. M. bovis has been found to have a dysgonic colony shape on Lowenstein-Jensen medium, be negative for niacin accumulation and nitrate reduction, and be susceptible to thiophene-2-carboxylic acid hydrazide (TCH). In contrast, M. tuberculosis has specific characteristics that differentiate it from M. bovis.