Coming in contact with a cat has caused two people to develop tuberculosis (TB) and two others to catch latent TB, experts said.
Occurring in the UK, Hampshire and Berkshire has produced nine pet cats with the TB infection. In a first of its kind cat-to-human TB transmission recorded, all nine cats have been admitted to the same veterinary surgery in Newbury, Berks, UK MailOnline reported.
A domestic cat, infected with Mycobacterium bovis, came in contact with some people. They later developed tuberculosis, Public Health England said.
According to PHE, there's a "very low" risk of TB transmission from cats to human beings.
However, nine cases of Mycobacterium bovis infection were also reported last year by the Animal Health and Veterinary Laboratories Agency (AHVLA) and PHE in Berkshire and Hampshire.
While the two people with the active infection of TB are responding positively to treatment, the other two infected with latent TB weren't required to seek medical attention, UK MailOnline reported.
TB is also caused by the Mycobacterium bovis bacteria in cattle and in other animals.
Samples, of the cats and affected humans, analyzed by the AHVLA revealed the M. bovis to be "indistinguishable." This "indicates transmission of the bacterium from an infected cat," PHE said.
It was not possible to confirm whether the cases of latent TB infection were also caused by M. bovis, UK MailOnline reported.
"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," Dr. Dilys Morgan, head of gastrointestinal, emerging and zoonotic diseases department at PHE, said.
"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 household and close contacts of cats with confirmed 'M. bovis' infection should be assessed and receive public health advice."