Mycobacterium bovis is the causative agent of bovine tuberculosis and is
an occasional cause of tuberculosis in humans. Human infection may be acquired by
ingestion of unpasteurised milk from infected cows and occasionally from direct
or aerosol contact with infected animals, which, in the UK, can include farmed deer.
Thus, groups with occupational contact with farm animals, such as farmers and veterinarians,
are also at increased risk of infection. Tuberculosis is a notifiable disease of
cattle and deer in the UK and, as such, subject to statutory control by routine
testing and slaughter of infected animals. The existence of a wildlife (Badger)
reservoir of infection in the UK and Ireland has contributed to the difficulty of
controlling the disease in cattle.
Main clinical features
The clinical presentation of TB in the UK can be:
Pulmonary, which is initially asymptomatic, followed by slow progression to fatigue,
fever and weight loss, and late in the disease, coughing and chest pain;
Non-pulmonary, which can affect a variety of other tissues and organs, such as lymph
nodes, joints, kidneys and the intestines, with symptoms dependent on which are
Usually 3 – 8 weeks, but occasionally 12 weeks from exposure. However, it
may take many decades for the disease to become manifest as clinical illness.
Enhanced Surveillance of Mycobacterial Infection (ESMI)
Annual Surveillance Tables