This section describes bovine tuberculosis (bTB) and outlines what is being done to control the disease.
bTB is a complex infectious zoonotic disease - which means it can be passed to humans from animals - caused by the bacterium Mycobacterium bovis (M. bovis). It presents a significant risk to animal health and welfare due to an increasing prevalence of the disease in UK cattle herds and other mammalian species, particularly badgers.
Approximately 22,000 cattle were slaughtered in the UK as part of the national bTB control scheme in 2004, costing the taxpayer approximately £88 million for the year and placing adverse pressure on the farming industry. In England, in 2009, bovine TB cost the taxpayer £63m and over 25,000 cattle were slaughtered for bovine TB control. It is not currently a significant threat to human health due to strict public health control measures, but it has the potential to become a threat if it is not kept in check.
What is being done to control the disease
Prior to the 1930s the main source of infection in humans was the consumption of infected un-pasteurised milk. The national eradication scheme in the 1940s and 1950s reduced this threat considerably and the prevalence of bTB stayed low in both human and cattle populations until the recent increase.
Cattle control measures have helped to eradicate bTB in other countries but the disease has increased significantly over the last 20 years in the UK, which some have attributed to the prevalence of bTB in the badger population.
It is important to recognise that successful control of bTB in countries where both cattle and wildlife reservoirs exist has only been achieved by addressing the infection in both wildlife and cattle populations.
The outbreak of Foot and Mouth Disease suspended bTB testing in 2001 and many culled herds were restocked without knowledge of the bTB status of the replacement animals. This is also thought to have contributed to the increased geographic spread and incidence of bTB in the last few years.
In addition to cattle controls, various forms of badger control have been trialled over the years and have produced inconclusive results. In 2005, after extensive consultation, the Government announced its TB Strategic Framework. This outlined a number of goals for the sustainable control of TB in the UK, including consideration of options for wildlife intervention and options to reduce the risk of disease spread through cattle movements.