Authorities concerned are closely monitoring a case in which cats have passed tuberculosis (TB) to humans. These are the first documented cases of cat-to-human transmission anywhere across the world.

Two people in England have been diagnosed with TB after contact with domestic cat infected with cat-to-human transmission. The bacterium is a major cause of TB in cattle and a bit less cause in other species.

Nine cases of M. bovis infection in domestic cats were diagnosed by a veterinary practice in Newbury, Berkshire from December 2012 to March 2013. But experts have said cats owners need not to worry. TB can be passed on from animals to humans, but risk to cat owners and their families is very less.

In a precautionary measure, screening was offered to 39 people who were found to have contact with the infected cats. Two cases of TB were found and confirmed. A further two cases of latent TB were identified.

Latent TB means that people had been exposed to TB at some point of time, but the disease is not in active form in them. TB is chronic infectious disease that is caused by bacteria within the Mycobacterium tuberculosis complex. Warm blooded animals can be infected with TB including farm animals, wildlife, pets and humans.

Though TB can affect any part of the body, it generally affects the lungs called as pulmonary tuberculosis. On the other hand, pets can catch TB through different measures like by having unpasteurized infected cows' milk or eating carcasses of infected animals.

By breathing in respiratory droplets from other infected animals. Symptoms of TB in pets include coughing, wheezing and weight loss. Wounds do not heal easily; lumps and abscesses are some other symptoms.

Another important part is route of TB transmission from pets to humans. It can be through respiratory droplets, from contaminated environment and by mouth.