Study proves disease connection in animals

Scientists have shown a link between bovine tuberculosis (bTB) in badgers and cattle - the first direct evidence to prove a connection between the two.

A study by the University of Glasgow and the Agri-Food and Biosciences Institute in Northern Ireland traced mutations in the bTB bacteria as it passed between badgers and cattle.

The scientists found that the types were extremely closely related and often indistinguishable between the bacteria types in badgers and those found in cattle from nearby farms. Cattle from farms even a few kilometres further away showed a lesser identical type.

The study involved 26 badgers and four cattle from Northern Ireland over a 10-year period. The bacteria, called Mycobacterium bovis, was analysed using genome sequencing technology (NGS).
 
Professor Rowland Kao, a senior research fellow at the University of Glasgow who led the study, said: "While the study was small, it provides the first direct evidence that the epidemic in the two species are closely linked."

However, bTB can be passed both ways and spread by infected cattle within herd, therefore, the scientists could not confirm the extent of the transition nor the direction of infection.

"Only a larger study will allow us to quanify the extent and direction of transmission between cattle and badgers and reliably inform disease control policies," added Prof Kao.