Cats carry a rare bacterium in their mouths and claws called Capnocytophaga canimorsus which could give you a life-threatening disease with just a lick and a scratch, the CDC warns.
While animals do not suffer ill effects, the bug can cause chronic infections in humans.
And according to the CDC, side effects of the potentially deadly disease are getting worse.
‘Cat-scratch fever causes fever, fatigue, headaches, and swollen lymph nodes. In extreme cases it can even cause brain swelling and heart infections.’
In a bid to curb the number of outbreaks, officials are urging cat owners not to kiss their pets, and to wash their hands as often as possible.
'The scope and impact of the disease is a little bit larger than we thought,' Dr Christina Nelson of the CDC said.
'Cat-scratch is preventable. If we can identify the populations at risk and the patterns of disease, we can focus the prevention efforts.'
Researchers found 12,000 people are infected each year, 500 of whom require hospital attention.
The disease comes from a bacterium which is passed from cat to cat. It is hard to trace the origin of how a particular cat got it. Many pick it up from flea feces.
Dr Aaron Glatt, chairman of medicine at South Nassau Community Hospital in New York, told NPR the rise in complications could be because more people are immunosuppressed today than 15 years ago.
'Most of the people who get seriously sick from cat-scratch are immunocompromised. The classic example is patients with HIV,' Dr Glatt said.
Dr Nelson believes it may simply be the case that infections were mis-categorized 15 years ago.
Regardless, she warns owners to refrain from petting cats, especially kittens. 'Younger cats are more likely to have bacteria in their blood,' Dr Nelson said.