The first documented cases of people catching tuberculosis from their cats were recently revealed in England, but experts say cat owners have little to fear.
The four cases were all linked to a cluster of sick felines in England, all of whom had bovine tuberculosis, which is carried by cows.
Between December 2012 and April 2013, veterinarians identified TB in nine pet cats in Berkshire and Hampshire, and Public Health England said the people who caught TB were recovering.
The report said the risk of the public catching TB from cats is "very low."
"This is an exceedingly rare, odd event, and there's no reason to be alarmed," Dr. Neil Schluger, chief scientific officer of the World Lung Foundation, told the New York Times. "Bovine tuberculosis represents maybe 1 percent of all the TB in the U.S., and the most common way to get it is drinking unpasteurized milk. Person-to-person transmission of TB is the only thing people need to worry about."
Selling unpasteurized, or raw, milk is illegal in many U.S. states and restricted in others.
Advocates of raw milk say it has many nutritional benefits, but a 2012 report by the CDC found that the majority of dairy-related disease outbreaks in the country are linked to unpasteurized milk.
The U.K. cats infected with bovine tuberculosis were likely infected by eating rodents that got the disease from cows or by fighting with badgers, which carry the bacteria.
The felines could have spread the disease to their owners by coughing or through wounds.
Tuberculosis kills more than 1 million people annually worldwide, but experts say cat owners are more likely to get cat-scratch disease, or Toxoplasma gondii, from their pets.
Cat-scratch disease is a bacterial infection that causes fever and swollen lymph nodes.
T. gondii can be dangerous to fetuses or people with weakened immune systems, but healthy people who contract it typically experience nothing worse than flu-like symptoms. Recently it's also been linked to personality changes and to suicide attempts.
Although it's been called the "cat lady parasite," experts say people are more likely to be infected with T. gondii from drinking contaminated water or eating unwashed vegetables or undercooked meat than by a cat.
Related on MNN: