Cat Scratch Disease

Cat Scratch Fever may sound like a good rock band name, but the disease itself is less than sensational. Produced by the bacteria Bartonella henselae, it causes swollen lymph nodes, fever, lack of energy and a host of other signs in humans. But where does it come from and how can humans get it?

What is the risk of acquiring Cat Scratch Disease?

With 100 million pets in the USA, we are always concerned about possible bugs that can transfer from cats and dogs to humans. In the United States, the risk of acquiring Cat Scratch Disease is about 1 in 10,000, so it’s an important disease to consider.

Do all people exposed to Bartonella spp. become ill?

Bartonella spp. infection does not always result in recognized illness in people. It’s common for mild cases to go unnoticed and resolve on their own, and many people can be exposed to the disease but not get sick. The prognosis for Cat Scratch Disease is usually favorable for healthy people, but those with compromised immune systems may require additional care.

What about my cat?

Since most infected cats show no signs of sickness, it’s hard to say if Bartonella spp. causes diseases in cats. It may be a factor in some illnesses, but it’s not understood if the bacteria alone can cause disease. However, fleas are known to accelerate and transfer Cat Scratch Disease, and we all know fleas can cause other problems as well!

So how do cats and people get the disease?

Exposure to fleas or flea feces is the most important consideration for transmission of Bartonella spp. between cats. In one test by the Colorado State Veterinary College, fleas from 92 cats from around the US were tested for Bartonella spp., and 20% of the cat fleas had the bacteria.

As a result, ingesting fleas or flea dirt can cause infection in cats. They may contaminate their claws and mouths with flea dirt during grooming. Fighting cats may have blood contact and can also transfer Cat Scratch Disease. Infected cats can then share with other cats or humans through bites or scratches (which is why it’s called Cat Scratch Disease!). Exposure to cat saliva can also spread the disease to humans.

How do we avoid the disease?

Fleas are nasty, dirty creatures! Preventing fleas year round on your cat and keeping them indoors is the most important prevention to this disease. Avoid bites and scratches when you’re playing with your cats, and wash your hands after handling any cats with fleas. There is no vaccine for Bartonella spp., so preventing fleas is the key to preventing Cat Scratch Disease.

Recommendations from the American Academy of Family Physicians:

  • Flea control should be initiated and maintained year-round.
  • If a family member is immunocompromised and a new cat is to be acquired, adopt a healthy cat that is over 1 year of age and free of fleas.
  • Immunocompromised individuals should avoid contact with cats of unknown health status.
  • Cat claws should be trimmed regularly, but declawing of cats is generally not required.
  • Scratches and bites should be avoided (including rough play with cats).
  • Cat-associated wounds should be washed promptly and thoroughly with soap and water and medical advice sought.

The materials, information and answers provided through this website are not intended to replace the medical advice or services of a qualified veterinarian or other pet health care professional. Consult your own veterinarian for answers to specific medical questions, including diagnosis, treatment, therapy or medical attention.

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