Bovine tuberculosis is a significant infectious disease in cattle, causing substantial economic costs and health impacts worldwide. However, a recent study led by the University of Cambridge and Penn State University has revealed promising findings that could potentially lead to the elimination and control of bovine tuberculosis.

The research indicates that vaccination not only reduces the severity of tuberculosis in infected cattle but also diminishes its spread in dairy herds by an impressive 89%. This groundbreaking discovery marks the first time that BCG-vaccinated cattle infected with tuberculosis have been shown to be significantly less infectious to other cattle, highlighting the indirect yet substantial impact of the vaccine beyond its direct protective effect.

It is estimated that zoonotic tuberculosis (zTB) infections from livestock account for approximately 10% of human tuberculosis cases. While zTB infections are commonly associated with gastrointestinal issues related to consuming contaminated milk, they can also lead to chronic lung infections in humans. These lung infections are often challenging to treat due to the natural antibiotic resistance in cattle bacteria.

The study, conducted in Ethiopia, demonstrated the effectiveness of the Bacillus Calmette-Guérin (BCG) vaccine in directly protecting vaccinated cattle and indirectly safeguarding both vaccinated and unvaccinated cattle by reducing tuberculosis transmission. Over a two-year period, vaccinated and unvaccinated animals were placed in enclosures with naturally infected animals in a unique crossover design.

The findings of the study are significant, as they not only emphasize the potential of BCG vaccination to mitigate the severity of tuberculosis in cattle but also underscore its ability to substantially reduce tuberculosis transmission, offering hope for the control and potential elimination of this infectious disease in cattle.