Nova Scotia

Doctor's warning: a cat's bacteria is worse than its bite

A Halifax emergency room doctor says people need to take cat bites seriously, due to the risk of infection from bacteria that live in the animal's mouth.

ER doctor says bites 'almost like getting stabbed with a needle' and infections can develop quickly

Dr. Sam Campbell says if you're bitten by a cat you should see your doctor right away.

A Halifax emergency room doctor says people need to take cat bites seriously, due to the risk of infection from bacteria that live in the animal's mouth. 

Every couple of days the emergency department at the QE II Health Sciences Centre in Halifax treats someone who has been bitten by a cat, said Dr. Sam Campbell, the chief of emergency medicine.

"A cat's teeth are very small so they inoculate these bacteria into your skin, but it's almost like getting stabbed with a needle," said Campbell.

Cats' mouths contain bacteria called Pasteurella multocida which can cause infections in humans. Most animals mouths have some form of bacteria that can cause infections including both dogs and people.

Bites 'progress quite quickly'

Should a cat bite become infected people usually start seeing swelling and redness around the bite area in about 24 hours. Campbell said other infections usually take around 48 to 72 hours to become noticeable.

He said animal bite infections "tend to progress quite quickly." He recommends people see a doctor whenever they're bitten by a cat, even if it doesn't look serious. 

"If it happens on a Friday and before Saturday afternoon your arm is starting to swell up I'd go to an emergency department, I wouldn't wait until Monday," he said. 
A cat bite that becomes infected becomes red and swells, says Dr. Sam Campbell. (Lincoln County Humane Society)

Most people head to the hospital when their wound begins to swell and turn red, said Campbell. Often people can see red streaks going up their arm. 

"It's relatively dramatic. It's not 'gosh I wonder if this is getting infected.'"

Antibiotics can treat infections

In most cases, doctors can treat people with antibiotic pills. Only in the most severe cases would someone be required to receive intravenous antibiotics or be hospitalised.

It can sometimes be difficult to diagnose people who have infections caused by cat bites if they have other medical conditions like diabetes, Campbell said. The severity of the infection can also depend on where a person has been bitten.

If antibiotic pills don't work, people can be treated with intravenous antibiotics to fight off an infection brought on by a cat bite. (iStock)

Hand infections require immediate attention because an infection can get into the tendon area, he said. 

"The tendon is like a brake on a bicycle, you have the cable and you have kind of tube around it," said Campbell. "If the infection gets between the cable and the tube...it can actually spread very quickly." 

Though they can be worrisome, the infections are rarely fatal. In the 27 years he's working in hospitals, Campbell said he has only seen two or three people die from these kinds of infections. 

Cat bites vs. dog bites

The bacteria in both cats and dogs mouths is not good for people.

But people who are bitten by dogs are more likely to seek treatment for the damage inflicted by the bite, which prevents an infection from development, Campbell said.

In contrast, cat bites are small so some people ignore them until they start to get infected. He believes that skews the numbers to make it look like more cat bites become infected.

Most cat bites can be treated with antibiotic pills, only the most serious cases see people ending up in hospital. (Submitted by Wanda Hodder )