A veterinary nurse and her dog have contracted bovine TB, raising fears that the high level of disease in some parts of the country could spread to more humans and pets.

The woman, from Cornwall, has been treated for the respiratory infection. Her daughter has also been tested for the disease and has received medication, The Times has learnt.

The incident was made public only after the Department for Environment Food and Rural Affairs (Defra) confirmed that it had started an investigation into how the disease had crossed species.

Information setting out the most likely scenario of whether the nurse was infected by the dog, or vice-versa, is expected to be published soon. The woman’s identity was not disclosed, but it is believed that she was involved in testing cattle for bovine TB.

It is extremely rare for people to contract the disease, but there is a greater risk for farmers and vets who work closely with infected animals.

The incident has alarmed vets and farmers, amid growing concerns over a decision by Hilary Benn, the Rural Affairs Secretary, to refuse a trial cull of infected badgers.

Badgers are being blamed for the spread of bovine tuberculosis through beef and dairy herds. Last year there were 4,137 outbreaks, a record in modern times, and 28,175 cattle were slaughtered as a result. Farmers claim that badgers spread TB by urinating on the fields grazed by cattle. Conservationists, though, believe that the disease is spread between cattle themselves and exploded only after 2001, when farmers restocked their herds after the foot-and-mouth crisis.

Experts are waiting to see how the disease was transmitted to the nurse and her pet and whether new wildlife controls to curb its spread are necessary. The Health Protection Agency played down fears of an increased threat to humans and said that the current risk in Britain was considered negligible.

Despite this, Roger Sainsbury, a former government veterinary officer in Cornwall, who specialised in bovine TB for 30 years, said “My real concern is that the number of cases in humans could increase because of the high incidence of TB in the environment.” He said that the threat was not confined to rural areas and was emerging closer to larger human populations.

“You could get contamination anywhere these days, even in a children’s sandpit, and disease can be transmitted through a cut,” he said. “This disease is not just confined to the South West, but in hotspots throughout the country.” Disease can be passed from a cat or dog to humans through open wounds or abscesses, coughs and sneezes. Any person can spread the disease through an open cut or if the disease is in the lung it can be spread by breathing over an animal. Mr Sainsbury said: “This is a very serious problem. We could do something about it but we are not and that is a travesty.”

Nicky Paul, a veterinary surgeon in Lostwithiel, Cornwall, who becomes the president of the British Veterinary Association this month, said that she was aware of the case and was waiting for the epidemiological study to be published. She said: “My biggest concern would be if the report showed the nurse had picked up the disease direct from handling a badger.”

Defra said that experts were awaiting the conclusions of the investigation. “Bovine TB is a recognised zoonotic agent and that is precisely why we have a compulsory bovine TB control programme in cattle.” According to the Health Protection Agency, in 2006, the latest year for which data is available, there were 33 cases of bovine TB in humans reported in Britain, of which six were in the South West. The agency confirms there were two cases in the South West in 2007.

However, in pets incidence of bovine TB is showing a small increase and it is recommended that any infected cat or dog is put down. Defra said that the disease had been found in 2 dogs and 11 cats so far this year. Locations have not been disclosed.

The cost of control

— In 2007 there were 2,215 confirmed cases of TB in Britain

— Current government policy is for animals that test positive for TB to be slaughtered with farmers compensated for the loss

— In 2007, 7,905 cattle were slaughtered to control the disease in Wales. In 1997 it was 669

— Compensation costs were £15.2 million last year. The bill in 2000-01 was £1.8 million

— Among worst-affected areas have been Pembrokeshire and Monmouthshire

— In 2007 the Welsh Assembly had to overcome a legal challenge to slaughter Shambo, a Hindu temple bullock. Police were called to remove Hindu worshippers so that animal health officials could take Shambo from the Skanda Vale religious community in Carmarthenshire

Source: Defra, Times Database

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