LONDON -- England's public health agency says two people have caught tuberculosis from a pet cat, the first time the bacterial disease has been documented to spread from cat to human.

In a report published Thursday, Public Health England said it concluded TB samples taken from the cat and from two people in contact with the animal were "indistinguishable" and that the cat was considered to be "the likely source of infection."

Between December 2012 and last April, veterinarians identified TB in nine pet cats in Berkshire and Hampshire, west of London. Public Health England said the two people who caught TB were recovering and said the risk of further spread from cats to humans is very low.

TB is a bacterial disease that kills more than 1 million people annually worldwide.