Cat Scratch Disease: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Cat Scratch Disease?
A primary care doctor usually treats cat scratch disease. People with severe or unusual cases may need an infectious disease doctor, a doctor who treats infections. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is cat scratch disease?
Cat scratch disease (CSD) is a bacterial infection caused by Bartonella henselae bacteria. It is also called cat scratch fever. People usually get it after being scratched by domestic or feral cats, especially kittens. The bacteria are often carried by fleas, and a scratch can carry flea waste that holds the bacteria. Cats can also spread the bacteria by biting or by licking an open wound.
Most cases of CSD are mild and go away on their own. But it can be serious in people with weakened immune systems.
Symptoms
Signs usually show up 1 to 3 weeks after contact with a cat. Common signs include:
- A small raised bump (a papule) or a bump with pus (a pustule) where the skin was scratched. This is often the first sign.
- Swollen, tender lymph nodes, which are small glands that fight infection, near the scratch or bite.
- Low-grade fever.
- Fatigue, headache, or general discomfort.
Some people also have loss of appetite, a sore throat, or weight loss. Rarely, the infection can spread to the eye, liver, spleen, brain, bones, or heart valves. Some of these rare infections happen mostly in people with weakened immune systems.
Causes and who gets it
The cause is infection with Bartonella henselae bacteria. Cats most often pick up the bacteria from flea bites. Many healthy cats carry it in their blood without getting sick, and some studies have found it in up to 1 in 3 healthy cats, especially kittens. Stray cats are more likely to carry it than pet cats.
CSD is most common in children under age 15, though people of any age can get it. People with weakened immune systems, such as those with advanced HIV, are at higher risk for severe disease.
How doctors diagnose it
Doctors can often diagnose CSD from the signs and a history of cat contact. No lab test is usually needed. A blood test for Bartonella antibodies can help in severe or unusual cases. Results are read along with the medical history, other lab work, or a biopsy. A lymph node biopsy is sometimes done to rule out other causes of swollen glands.
Treatment
Most cases get better without treatment. Antibiotics may help swollen lymph nodes improve faster, so a doctor may offer them based on how bad the symptoms are. Antibiotics are recommended for everyone with a weakened immune system. In rare spread-out infections, such as eye or heart valve disease, longer courses with more than one antibiotic may be needed, with an infectious disease expert guiding care.
When to see a doctor
See a doctor if you have swollen lymph nodes and you have been around a cat. Rarely, the infection can spread to the brain and cause encephalopathy, a loss of brain function. Call 911 if you or your child has confusion or unusual behavior, a seizure, trouble breathing, fainting, or a sudden change in vision.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Such a doctor can examine the scratch and swollen nodes, follow the illness over time, and coordinate care with an infectious disease doctor if the case is severe.
Common questions
Can a cat have the bacteria without being sick?
Yes. Most cats that carry Bartonella henselae simply have it in their blood without getting sick. Kittens are especially likely to carry and pass it. Testing and treating a healthy cat for the bacteria is not recommended.
How is cat scratch disease prevented?
Avoid cat scratches, bites, and licks, especially from kittens or stray cats. Wash your hands after handling cats, and clean any scratch wound with soap and water. Ask your veterinarian about flea control for your cat, and keep cats indoors away from stray cats.
Do I need antibiotics for cat scratch disease?
Usually not. Most cases clear up on their own. Antibiotics may help reduce lymph node swelling faster and are recommended for people with weakened immune systems.
Is cat scratch disease serious?
Usually no. It is often mild, and people with healthy immune systems should recover fully without treatment. It can become serious, though, in people with weakened immune systems. Rare infections of the eye, liver, spleen, brain, bones, or heart valves can occur.
Sources
- MedlinePlus Medical Encyclopedia - Cat-scratch disease
- CDC - About Cat Scratch Disease | Bartonella Infection
- CDC - Clinical Overview of Cat Scratch Disease
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
