Patient education: Rocky Mountain spotted fever (The Basics)

What is Rocky Mountain spotted fever? — 

This is an infection that typically causes a fever and a blotchy rash. 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? — 

Symptoms usually start within 2 weeks of being bitten by an infected tick. They include:

●Fever (in almost all cases)

●Headache, which can be severe

●Flu-like illness

●Muscle and joint pain

●A skin rash

●Darker skin around the bite

●Nausea, with or without vomiting

●Belly pain (especially in children)

●Bleeding more easily than normal

●Confusion, or changes in behavior

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 then spreads to the rest of the body. Over time, the blotches form tiny bruises.

The rash takes a few days to show up, so it's not always obvious right away that Rocky Mountain spotted fever is causing the other symptoms.

Is there a test for Rocky Mountain spotted fever? — 

Yes, a blood test 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 the 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. 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? — 

Tell your doctor. This might change which antibiotic you get.

When should I call the doctor? — 

Call your doctor or nurse right away if:

●You were bitten by a tick, and develop any of the symptoms listed above.

●Your symptoms do not start to improve after 1 day of taking antibiotics.

Call for advice if you have a fever and a rash, even if you were not bitten by a tick.

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