What is Rocky Mountain spotted fever?

Rocky Mountain spotted fever is a bacterial infection that can be life-threatening if you don’t treat it early. People get this infection when bitten by an infected tick.

When and where do people get Rocky Mountain spotted fever?

Despite its name, Rocky Mountain spotted fever can occur many places in the U.S, most commonly in the central and eastern states, including Missouri, Arkansas, the Carolinas and Tennessee. It also exists in Canada, Mexico, and areas of Central and South America.

You can get Rocky Mountain spotted fever at any time of the year. However, most cases happen during the warm summer months, when people are more likely to be exposed to ticks.

What causes Rocky Mountain spotted fever?

Bacteria called Rickettsia rickettsii causes Rocky Mountain spotted fever. The bacteria is spread to people through the bite of a tick. The ticks that carry this disease include the Rocky Mountain wood tick, the American dog tick, and the brown dog tick.

What are the symptoms of Rocky Mountain spotted fever?

Rocky Mountain spotted fever causes symptoms including a headache, fever and rash. Symptoms usually show up 2 to 14 days after a tick bite.

These symptoms are common to many illnesses, including influenza and meningitis. If you develop these symptoms and have been bitten by a tick or spent time in areas where ticks live, it is important to see a doctor because the disease can get worse very quickly.

Though the name “spotted fever” suggests a rash, not everyone with Rocky Mountain spotted fever develops a rash and it may be difficult to see on people with darker skin. If a rash does develop, it usually appears 2 to 4 days after the fever starts. The red dots of the rash can look different in different cases. They can range from small dots to large blotches.

Symptoms of Rocky Mountain spotted fever can get worse soon after the initial symptoms appear. See a doctor if you experience more severe problems including:

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