When should I worry about a cat scratch? Here's what experts say.

Cats are cute, and studies have shown that having one as a pet can reduce anxiety and even slow mental decline. Sometimes, however, their claws can get a little too close for comfort, leaving humans with a painful scratch.

But do those scratches ever need more than a Band-Aid (and perhaps a reminder to trim Fluffy's nails)? In some cases, a cat scratch can result in a worrisome infection that requires medical attention. What symptoms should you watch out for, and how can you prevent your cat from carrying these infections in the first place? Ahead, experts break it all down.

Why should I worry about a cat scratch?

Cat scratches are typically not something to worry much about, says Dr. Barbara Bawer, a family medicine physician at the Ohio State University Wexner Medical Center in Columbus, Ohio. Most of the time, she says, “they are benign except for the actual sting and the scratch itself as it heals.” There may be potential issues, however, if the scratch site becomes infected, as “cats can transmit certain viruses and bacteria,” she adds.

The best-known of these infections? Cat scratch disease (CSD), which is also sometimes called cat scratch fever, occurs when someone comes into contact with Bartonella henselae bacteria, according to Verywell Health.

“CSD is most commonly seen in children and young adults,” says Dr. Tom Waters, an emergency medicine physician at the Cleveland Clinic. “It typically manifests as redness and bumps at the scratch site, along with the hallmark of swollen lymph nodes near the scratch site.” Other symptoms of CSD include fever, muscle aches, nausea, abdominal pain and loss of appetite.

While cats aren’t the only animals that can transmit this, they’re the main carriers, and don’t show symptoms of this disease themselves. Cats typically get this infection when they are infected by fleas. You can avoid the potential of your cat passing along CSD by setting up a flea treatment plan for your cat.

It’s possible for any cat to pass along this bacteria and infect a human with CSD, however, it’s much more typical with stray cats, says Waters, as they are “more likely to have fleas and thus there may be a higher likelihood of cat scratch disease in a person who is scratched by a stray.” Kittens in particular are more likely to be infected with and pass along CSD, and are also considered more likely to scratch and bite a human while playing compared to an older cat. But CSD isn't just spread through scratches; a cat can also infect someone by licking their open wound or bite.

What else can a cat scratch cause?

In very rare cases, it’s possible for a cat scratch to pass along something more serious than CSD, like rabies, a viral disease that is almost always fatal once symptoms appear. However, it’s unlikely for a domestic cat to be a rabies carrier, with most of the animal-to-human infections coming from bats and dogs who have not been vaccinated against the disease, according to Verywell Health. It’s also rare for a scratch to cause rabies, as one needs to come in contact with the saliva of an infected animal.

If you suspect your cat has come in contact with an animal that may be infected by rabies, such as a bat, avoid contact with them and call your veterinarian, as well as animal control, right away. Let them know if your pet has been vaccinated for rabies as well.

In February, health officials in Oregon shared their suspicions of the "likely" source behind the state's first case of the bubonic plague in a human in eight years: a symptomatic pet cat. “All close contacts of the resident and their pet have been contacted and provided medication to prevent illness,” said Dr. Richard Fawcett, health officer for Oregon's Deschutes County, in a release.

The disease is typically spread by fleas carrying the bacterium Yersinia pestis; household pets can get infected via a flea bite or contact with an infected animal, such as a rodent. Though it's rare for the plague to spread from a cat to a human — there are only seven cases of human plague, total, on average in the U.S. — a scratch wouldn't necessarily have to be involved. Humans can be infected though contact with a cat, including exposure to respiratory droplets from the animal's cough or sneeze, or by being bitten by an infected flea carried home by the cat.

What to do if you're scratched by a cat

If you do get scratched by a cat, be it your pet, a loved one’s animal or a stray, it’s not necessary to go straight to the emergency room, says Waters. Instead, you should thoroughly clean and disinfect the scratch, either at home or in a doctor’s office, and then keep an eye out for any unusual symptoms. As the CDC notes, "the infected area may appear swollen and red with round, raised lesions and can have pus. A person with CSD may also have a fever, headache, poor appetite, and exhaustion. Later, the person’s lymph nodes near the original scratch or bite can become swollen, tender or painful."

Typically, people recover from CSD without treatment but may need antibiotics. Those at higher risk of more serious illness include people between the ages of 5 and 14 and those with weakened immune systems, according to the Centers for Disease Control and Prevention. Rarely, CSD can affect the brain, eyes, heart or other internal organs.

Trying to avoid cat scratches in the first place is a great way to prevent potential sickness from felines. Don’t try to cuddle your cat when he’s in a mood — and keep a safe distance from any strays.

This article was originally published on Feb. 7, 2024 and has been updated.