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Cat Scratch Fever: What It Is and How to Avoid It

Cat scratch fever is spread by fleas.

Cat scratch disease, more commonly known as cat scratch fever, is a bacterial infection that is spread from cat to cat and from cats to humans.

What Causes Cat Scratch Disease?

Cat scratch disease (CSD) is caused by the bacteria Bartonella henselae. In cats, CSD doesn't usually cause any signs of illness. However, in some cats, the bacteria can attack the heart, causing life-threatening complications.

Around 40% of cats will be infected by Bartonella henselae at some point in their lives, so it's a pretty common bacteria.

Kittens are more likely to be infected by B. henselae than older cats.

How Do Cats Become Infected with Cat Scratch Fever?

People are infected with B. henselae through flea bites or when flea droppings (flea dirt) contaminates a wound on their skin. They can also get it by fighting with other cats that are infected.

How Do People Get Cat Scratch Disease?

When cats scratch and bite at their fleas, they end up with flea dirt in their teeth and under their nails. If that flea dirt is contaminated with B. henselae, the cat can then spread cat scratch disease to humans when they bite, scratch, or lick a person's broken skin.

Symptoms of Cat Scratch Disease in People

People who are infected with CSD get red, swollen, pus-filled wounds at the site of infection. They usually get a headache, fever, become fatigued, and lose their appetite. The infection spreads to the lymph nodes, which become swollen and painful.

Some people can become seriously ill with CSD if the bacteria invades the heart, brain, or other organs. Young children, seniors, and people with compromised immune systems are more likely to suffer from these types of severe symptoms.

Most of the time, treatment isn't necessary for CSD, but your doctor will determine this.

Avoiding Cat Scratch Fever

People should always thoroughly wash any cat bite or scratch with soap and warm water, then visit their doctor right away.

Don't allow cats to lick broken areas of your skin.

Control fleas on your cat and in your home. Check with your veterinarian to determine the best flea preventative for your cat. Do not use over-the-counter flea products on your cat without checking with your vet first. Don't use flea products on a cat that are meant for dogs because they can cause severe toxic reactions or death.

Inspect your cat often for fleas and flea dirt.

Keep your cat inside to make flea infestation less likely and to keep your cat from fighting with other cats and potentially becoming infected that way.

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