US: TB vaccination to reduce spread in dairy herds by 89%

The study, led by the University of Cambridge and Penn State University, improves prospects for the elimination and control of bovine tuberculosis – a disease that results in large economic costs and health impacts globally. This is the first study to show that BCG-vaccinated cattle infected with TB are substantially less infectious to other cattle. This remarkable indirect effect of the vaccine beyond its direct protective effect has not been measured before. The spillover of infection from livestock has been estimated to account for about 10% of human tuberculosis cases. While such zoonotic TB (zTB) infections are most commonly associated with gastro-intestinal infections related to drinking contaminated milk, zTB can also cause chronic lung infections in humans. Lung disease caused by zTB can be indistinguishable from regular tuberculosis, but is more difficult to treat due to the natural antibiotic resistance in the cattle bacteria. TB remains endemic in many countries around ...