Two people in England have developed bovine TB tuberculosis after contact with an infected domestic cat. These are the first documented cases of bTB passing between the two species.

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Although the 'Mycobacterium bovis' bacterium is most known for infecting cattle (and badgers), a whole host of other animals are susceptible, including humans, cats, foxes, deer and pigs.

Public Health England (PHE) and the Animal Health and Veterinary Laboratories Agency (AHVLA) announced on Thursday that, after nine cases of 'M. bovis' infection in domestic cats in Berkshire and Hampshire had been investigated by AHVLA and PHE during 2013, the government public health body had offered TB screening to 39 at-risk people. Of the 24 who chose to undergo screening, two were found to have cases of latent TB.

Though neither person had active TB disease, both have been receiving treatment, PHE said. The last reported cases of bTB in the area were in March 2013. PHE has assessed the risk of transmission of 'M. bovis' from cats to humans as being "very low."

Dr Dilys Morgan, a PHE spokesperson, said, "It's important to remember that this was a very unusual cluster of TB in domestic cats. 'M. bovis' is still uncommon in cats - it mainly affects livestock animals.

"These are the first documented cases of cat-to-human transmission, and so although PHE has assessed the risk of people catching this infection from infected cats as being very low, we are recommending that households and close contacts of cats with confirmed ‘M. bovis’ infection should be assessed and receive public health advice."

Transmission of ‘M. bovis’ from infected animals to humans can occur by inhaling or ingesting bacteria shed by the animal or through contamination of unprotected cuts in the skin while handling infected animals or their carcasses.

Professor Noel Smith, Head of the Bovine TB Genotyping Group at AHVLA, said, "Testing of nearby herds revealed a small number of infected cattle with the same strain of 'M. bovis' as the cats. However, direct contact of the cats with these cattle was unlikely considering their roaming ranges."

Prof Smith suggested that "The most likely source of infection is infected wildlife, but cat-to-cat transmission cannot be ruled out."

Cattle herds with confirmed cases of bovine TB in the area have all been placed under movement restrictions to prevent the spread of disease. The two groups said health professionals in the region remain vigilant, in case of further infections in cats, livestock or humans in the area.