- Not a substitute for professional veterinary help.
Cat scratches can happen when playing with a cat, if they are scared, or if a child is learning how to handle them. If a cat scratches you, you might worry about getting sick from cat scratch disease (CSD), also known as cat scratch fever.
Luckily, CSD is rare in people. While humans might get a fever or swollen lymph nodes, cats carrying the Bartonella bacteria usually don’t show any signs of illness.
“Humans can be infected with B. hartonella from cat scratches, and cats themselves are infected via fleas and possibly other parasites,” explains Sam Taylor, a veterinarian at International Cat Care.
Here’s what you need to know if a cat scratches you or someone you care about and how to spot, diagnose, and treat CSD.
What Causes Cat Scratch Disease?
CSD can be traced back to a cat scratch, bite, or a cat licking an open wound. “It comes from cats who are infected with a bacterium called Bartonella henselae,” explains Rebekah Diamond, a board-certified pediatrician at Columbia University Department of Pediatrics.
Cats are infected with B. henselae from parasites such as fleas and ticks. Rarely, humans get CDS when bitten by a tick or flea themselves.
How Common is Cat Scratch Disease?
Thankfully, cat scratch disease is rare in humans. The NIH estimates that about 12,000 people are diagnosed with CSD a year. Most of those cases are children between the ages of five and nine. “This makes sense as they are most likely to get scratched playing with kittens,” says Monica Wonnacott, a pediatrician and founder of PediatricAnswers.
Most cats carrying the bacteria seem perfectly healthy, but the CDC says up to a third of cats might carry it.
Taylor says cats not treated regularly for fleas and ticks are most likely to have the bacteria. These are usually feral cats, strays, and kittens. Most cases happen in southern states where fleas and ticks are around all year.
What Are the Symptoms of Cat Scratch Disease?
Most cats carrying Bartonella don’t show any signs of being sick. In rare cases, they might have a fever and inflammation in some organs.
For humans, here’s what to watch for:
- A bump, blister, or sore near the scratch or bite within 12 days.
- Swollen lymph nodes, usually in the armpit (for scratches on arms or hands), within 2-3 weeks.
- Fever
- Headache
- Nausea
How Do Vets Diagnose Cat Scratch Disease?
Vets don’t usually test cats for Bartonella because it doesn’t make them sick. However, Taylor says vets might test a cat’s blood if the cat has symptoms or inflammation.
If you or your child shows any signs of CSD after being scratched by a cat, see your doctor. They will do a physical exam, and in most cases, this is enough for a diagnosis. Some doctors might also recommend a blood test or a biopsy of the swollen lymph node.
How Do You Treat Cat Scratch Disease?
Cats carrying Bartonella usually get better on their own and don’t need treatment. If a cat tests positive for Bartonella, a vet would give them antibiotics.
There’s good news for people, too. Diamond and Wonnacott say most CSD cases get better on their own. But antibiotics might be needed for severe cases or for people with weak immune systems.
If left untreated, CSD can lead to rare but serious symptoms like:
- Brain inflammation
- Eye problems
- Bone infection
It can take weeks to months for CSD symptoms to go away. Fortunately, CSD is not contagious.
Is Cat Scratch Disease Preventable?
The best way to prevent Bartonella is to keep up with your cat’s monthly flea and tick treatments. Preventing flea infestations helps prevent CSD and protects your cat from other health problems like tapeworms.
Avoiding cat bites and scratches helps prevent infections. “We should never play with our cats using our hands, or roughly, even with kittens, and we should always give a cat space and choice around interacting with us,” Taylor adds.
Regularly clipping your cat’s nails can help prevent scratches and keep your cat comfortable. Never declaw a cat.
What To Do If a Cat Scratches or Bites You
If a cat scratches you, clean the wound thoroughly with soap and water.
Because infections are common on the fingers and hands, doctors usually prescribe preventative antibiotics for cat bites before signs of an infection appear.
