Patient education: Rocky Mountain spotted fever (The Basics)

What is Rocky Mountain spotted fever? — Rocky Mountain spotted fever is an infection that typically causes a fever and a blotchy rash of red spots. You can get this infection if you are bitten by a tiny insect called a tick. When a certain type of tick bites you, it can transmit the germ that causes Rocky Mountain spotted fever from its body to yours.

The ticks that can carry the germ that causes Rocky Mountain spotted fever are called the American dog tick, the Rocky Mountain wood tick, and the common brown dog tick (picture 1). These ticks normally feed on animals, including dogs.

What are the symptoms of Rocky Mountain spotted fever? — The symptoms can include:

●Fever (in almost all cases)

●Headache, which can be severe

●Flu-like illness

●Muscle and joint pain

●Nausea, with or without vomiting

●Belly pain (especially in children)

●A skin rash (described in more detail below)

The rash caused by Rocky Mountain spotted fever causes red blotches that turn white if you press on them (picture 2). The rash can be hard to see on dark skin. It usually starts on the ankles and wrists and spreads to the rest of the body.

The rash takes a few days to show up, so it's not always obvious right away that Rocky Mountain spotted fever is to blame for the other symptoms. Over time, the blotches form tiny bruises.

Should I see a doctor or nurse? — See your doctor or nurse right away if you were bitten by a tick and develop a fever and any of the other symptoms above. Even if you were not bitten by a tick, see your doctor or nurse if you have a fever and a rash.

Is there a test for Rocky Mountain spotted fever? — Yes, there is a blood test that can show whether you have Rocky Mountain spotted fever. But the results of the test take a long time. Doctors usually must diagnose the infection based on symptoms and begin treatment as soon as possible. Doctors can also look for the germ that causes Rocky Mountain spotted fever in a sample of skin. But that test can only be done after the rash shows up.

How is Rocky Mountain spotted fever treated? — It is treated with antibiotics to fight the infection. If there is a chance you have Rocky Mountain spotted fever, it is important to start these antibiotics as soon as possible. The infection can be deadly if it is not treated in time.

What can I do to try to avoid getting bitten by a tick? — You can:

●Wear shoes, long-sleeved shirts, and long pants when you go outside. Keep ticks away from your skin by tucking your pants into your socks.

●Wear light colors so you can spot any ticks that get on your clothes.

●Use bug spray to keep ticks away. On your skin, use bug sprays that have a chemical called "DEET." On your clothes and gear, use bug repellants that have a chemical called "permethrin."

●Check your body for ticks after being outdoors or with dogs. Be sure to check your scalp, waist, armpits, groin, and backs of your knees. If you have children, check them for ticks, too.

What if I am pregnant? — If you are pregnant, be sure to tell your doctor. This might change which antibiotic you get.

More on this topic

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Patient education: Lyme disease treatment (Beyond the Basics)