Cat Scratch Fever in Cats: Understanding, Treating, and Preventing Cat-Scratch Disease

Playful pets may harbor unseen bacteria, so hygiene helps safeguard cats and owners.

By Medha deb

Created on Aug 29, 2025

Playful pets may harbor unseen bacteria, so hygiene helps safeguard cats and owners.

Cat scratch feverâalso known as cat scratch disease (CSD)âis an infectious disease primarily caused by the bacterium Bartonella henselae. This disease is most commonly transmitted to humans and other animals through scratches, bites, or even licks from infected cats. Though often mild, CSD can occasionally become serious, especially in people or pets with compromised immune systems. Here’s everything you need to know about cat scratch fever in cats: its causes, symptoms, diagnosis, treatment, and prevention.

What Is Cat Scratch Fever?

Cat scratch fever is an infection caused by the bacterium Bartonella henselae. The disease mainly affects humans who are scratched, bitten, or licked by an infected cat, but cats themselves can be carriers and occasionally display symptoms.

Cats often contract B. henselae via flea bites or fights with other infected cats.
The bacterium is carried in catsâ bloodstreams; most cats show no obvious signs of illness.
While most human infections are mild, some can develop serious complications if untreated, especially in people with weakened immune systems.

How Do Cats and Humans Get Cat Scratch Fever?

Cats become infected with B. henselae primarily through fleas. Fleas transmit the bacteria between cats, and the bacteria multiply in the catâs blood.

Cats rarely get sick from B. henselae, but they can shed the bacteria in their saliva and on their claws.
Humans usually contract the infection when a cat:

Scratches or bites deeply enough to break the skin
Licks an open wound or broken skin

Cat scratch fever is not spread from person to person.

Who Is at Risk?

Anyone in contact with cats can get cat scratch fever, but certain groups are at greater risk:

Childrenâespecially those under 5, as they often have closer contact with kittens
People with weakened immune systems (due to illness, age, or medication)
Individuals who work in animal shelters, veterinary clinics, or rescue organizations

Signs and Symptoms of Cat Scratch Fever

In both humans and (less commonly) cats, cat scratch disease manifests with several telltale symptoms:

Primary lesion: Within 3â14 days of exposure, a small bump, blister, or pustule appears at the scratch or bite site.
Swollen lymph nodes: Usually develop 1â7 weeks after the initial lesion, near the site of the scratch (e.g., in the armpit if the scratch is on the arm).
Pain and tenderness: Affected lymph nodes may be painful and can grow up to 6 cm in diameter.
Mild fever: Not uncommon, especially in children.
Fatigue, headache, and general discomfort: May accompany the above.
Rarely, serious complications can affect the brain, eyes, heart, or other organs, particularly in immunocompromised people.

Table: Typical Progression of Cat Scratch Fever Symptoms

Time After Exposure	Symptoms
3â14 Days	Small bump, blister, or pustule at site of injury
1â7 Weeks	Swollen lymph nodes, mild fever, headache, fatigue
Months (in rare cases)	Serious complicationsâneurological, ocular, cardiac

How Do Veterinarians Diagnose Cat Scratch Fever?

Diagnosis in cats (and humans) relies on a combination of history, physical examination, and, when needed, laboratory testing:

Veterinarians will inquire about any recent scratches, bites, bites received by owners, or exposure to stray or feral cats.
Physical exams focus on identifying lesions, swollen lymph nodes, fever, or unusual behavior.
Blood tests (serology or PCR) can confirm the presence of B. henselae in cats. However, most cats do not exhibit signs, so testing is rarely done unless the cat is ill or used in research.
In suspected human cases, doctors may use blood tests to detect antibodies or, in rare cases, sample lymph node fluid.

Treatment for Cat Scratch Fever

Most cases of cat scratch fever resolve on their own within a few weeks to several months, both in cats and humans. Specific treatments are reserved for severe or prolonged cases, or those involving at-risk populations.

For healthy individuals:
- Treatment is often supportiveârest, pain relievers (like ibuprofen or naproxen), and warm compresses for swollen nodes.
For severe or prolonged symptoms, or in immunocompromised individuals:
- Antibiotics may be prescribed, such as:
- Antibiotic course typically lasts 5â14 days, depending on the medication and the severity of the case.
- In some cases, swollen lymph nodes may be drained to relieve pain.
For cats:
- Healthy cats rarely require treatment unless they show signs of illness.
- Cats showing symptoms or those with compromised immune systems may receive antibiotics under veterinary supervision.

At-Home Care for Humans

Keep affected area clean and covered
Apply warm, moist compresses to swollen glands
Use over-the-counter NSAIDs to reduce pain and swelling
Monitor for signs of worsening condition or complications (e.g., persistent fever, spreading lymph node swelling)

Complications of Cat Scratch Fever

While most cases are mild, cat scratch fever can occasionally cause complications, especially in those with weakened immune systems:

Parinaud oculoglandular syndrome: Swelling of the eye and nearby lymph nodes
Neuroretinitis: Inflammation of the eye affecting vision
Encephalopathy: Rare brain infection, causing confusion or seizures
Endocarditis (heart infection)
Severe, widespread infection requiring hospitalization

Prompt veterinary and medical attention are recommended if complications are suspected.

How to Prevent Cat Scratch Fever

Prevention focuses on reducing risk of exposure to B. henselae for both cats and people:

Flea control: Regular flea prevention for all household cats is key, since fleas spread the bacteria among cats.
Safe play: Avoid rough play with cats that might lead to scratches or bites.
Hand hygiene: Always wash hands with soap and water after handling cats or cleaning litter boxes.
Wound care: Promptly clean scratches, bites, or licked wounds with soap and water.
Trimming claws: Regular nail trimming reduces the likelihood of deep scratches.
Keep cats indoors: This limits their exposure to fleas and infected animals.
Avoid stray or feral cats: Especially important for children, the immunocompromised, and the elderly.
People with weakened immune systems should consider adopting adult cats rather than kittens, as kittens are more likely to carry the bacteria.

When to See a Veterinarian or Doctor

Seek veterinary advice if your cat develops signs of illness, wounds, fever, or lethargy persisting beyond a few days.
Consult your doctor if you, your child, or anyone in the household develops:

Swollen, tender lymph nodes that last longer than two weeks
Persistent or high fever
Difficult-to-heal lesions
Unusual symptoms (vision changes, confusion, chest pain)
History of immune deficiency and possible exposure

Living with Cat Scratch Fever: Prognosis and Outlook

Most cases of cat scratch disease are mild and resolve without intervention. However, some cases require antibiotics or further treatment. Prognosis is excellent in healthy individuals and cats.

Symptoms may last from a few weeks to several months, with bumps or blisters healing in 1â3 weeks and swollen lymph nodes potentially taking 2â4 months to subside.
Severe, prolonged, or complicated cases may require more intensive medical care but generally have good outcomes if detected early and treated properly.

Frequently Asked Questions (FAQs) about Cat Scratch Fever

Q: Can my cat get sick from cat scratch fever?

A: Most cats infected with Bartonella henselae do not develop noticeable signs of illness. However, some may experience mild fever, swollen glands, or lethargy. If your cat appears ill, consult your veterinarian for evaluation and treatment.

Q: How long does cat scratch fever last in people?

A: Most people recover within a few weeks to several months, depending on the severity and immune status. Swollen lymph nodes can persist for 2â4 months, and rarely up to a year.

Q: Can cat scratch fever be fatal?

A: Cat scratch fever is rarely fatal in healthy individuals. The risk of severe complications increases in people with weakened immune systems, but with proper medical care, the prognosis remains good.

Q: Should I get rid of my cat if someone in the family gets cat scratch disease?

A: No. With good hygiene and flea control, most people and cats can safely live together. Those at higher risk should practice extra precautions and discuss options with their healthcare provider and veterinarian.

Q: How can I reduce my cat’s risk of carrying Bartonella?

A: Keep your cat indoors, maintain regular flea prevention, and schedule routine veterinary exams. Avoid allowing cats to hunt or contact unknown, outdoor, or feral animals.

Key Points for Cat Owners

Cat scratch fever is caused by Bartonella henselae and is spread mainly via flea-infested environments and cat-to-cat contact.
Cats rarely show illness, but can carry the bacteria and transmit it to people through scratches, bites, or licks.
Prevention focuses on flea control, safe handling, and basic hygiene.
Inform your doctor and veterinarian if anyone in your household is immunocompromised or if your cat shows sudden signs of unexplained illness.

Summary Table: Cat Scratch Fever (Cat Scratch Disease)

Aspect	Details
Cause	Bacterium Bartonella henselae
Transmission	Flea bite to cat; cat scratch, bite, or lick to human
Symptoms (humans)	Skin bump, swollen lymph nodes, fever, fatigue, rare severe complications
Symptoms (cats)	Usually none; rarely, fever or swollen glands
Treatment	Often self-resolving; antibiotics for severe or prolonged cases
Prevention	Flea control, safe handling, good hygiene, keep cats indoors

References

This article synthesizes current evidence and guidelines from reliable sources, including pet health organizations and infectious disease experts, to provide an accurate and informative overview of cat scratch fever in cats. For further reading, consult your veterinarian or physician.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

Read full bio of medha deb