The majority of outbreaks of bovine TB within cattle herds are caused by multiple transmissions routes – including failed cattle infection tests, cattle movement and reinfection from environmental reservoirs such as infected pastures and wildlife – according to the first national model of bovine TB spread, published today.
The model, developed by researchers at the University of Warwick and University of Cambridge, suggests that improved testing, vaccination of cattle and culling of all cattle on infected farms would be the most effective strategies for controlling the disease. It found that whilst badgers – the subject of controversial culling plans to stem the spread of the disease – form part of the environmental reservoir, they only play a relatively minor role in the transmission of infection.
Based on a study of cattle and the causes of bovine TB in Great Britain, the model, published in the journal Nature, sought to ascertain how and why the epidemic has grown over the past 15 years. Using data from the Animal Health and Veterinary Laboratories Agency and the Department for the Environment, Food and Rural Affairs (Defra), the researchers developed a mathematical model that incorporated both within- and between-farm bovine TB transmission.
“Our model offers a dispassionate, unbiased view of the spread of bovine TB through the cattle industry of Great Britain,” says Professor Matthew Keeling, from the University of Warwick’s School of Life Sciences and Department of Mathematics. “The model is based on the recorded pattern of positive and negative tests and uses the known movement of cattle around the country. We aim for it to provide policy-makers with the best evidence possible from which to make decisions relating to bovine TB and to contribute to the ongoing discussions on this sensitive issue.” Read more..