Public health officials announced on Thursday, Dec. 22, that a veterinarian working at a New York animal shelter may have contracted a rare form of the bird flu virus while treating sick cats. If the case is confirmed, it will be first instance of cat-to-human transmission of the virus.

According to New York City's Health and Mental Hygiene Department, a rare strain of the flu virus was detected in at least 45 cats at an animal shelter in Manhattan.

Laboratory tests conducted at the University of Wisconsin revealed that the infection was caused by the H7N2 virus, which appears to have jumped from birds into cats.

Dr. Jay Varma from the New York City health department explained that they get very concerned whenever a virus adapts to a new carrier animal since there is a likelihood that the infection could be transmitted from the sick animal to the people that care for them.

Cat-To-Human Bird Flu Transmission

While cats have contracted the bird flu virus before, Thursday's announcement marks the first time when the H7N2 viral strain was transmitted from infected cats to humans.

Health officials believe the veterinarian may have gotten the virus from a frail, 12-year-old cat that was taken to the animal shelter. They suspect that it may have come in contact with a sick pigeon or another cat that already had the infection.

Varma said the cat developed mild illness at first, which eventually progressed to pneumonia. The animal was later euthanized because the infection had become severe.

"It was the humane thing to do," Varma said.

Most of the other cats at the animal shelter that tested positive for the rare bird flu virus have only shown mild symptoms of the infections. The city health department said the animals are expected to recover from the illness and that the likelihood of further transmission is very low.

The vet was the only one that showed symptoms of the H7N2 infection out of the dozens of people screened.

The patient had been exposed to respiratory secretions from sick cats while working at the Manhattan shelter of the Animal Care Centers of NYC. Officials said the vet had since recovered from the mild illness.

The New York City health department said individuals who show flu-like symptoms are likely to have seasonal influenza or other respiratory-related infections commonly associated with winter. H7N2 and seasonal influenza both have similar symptoms and are treated using the same medications.

Both illnesses are particularly devastating to pregnant women and individuals with existing health problems or weakened immune systems.