Besides sunburn and dehydration, there is another thing for hikers and parents to worry about this summer.

Michigan has confirmed that a child has been diagnosed with the state’s first case of Rocky Mountain spotted fever (RMSF) since 2009.

RMSF is a tick-borne illness caused by the Rickettsia rickettsii bacterium. Its most distinctive symptom is a red, spotted rash that doesn’t itch.

However, not every person who comes down with the infection will get a rash. Other early symptoms include headache, abdominal pain, fever, and confusion.

People who receive prompt treatment usually make a full recovery. Untreated, RMSF can cause serious damage to internal organs such as the kidney and heart.

Three different types of ticks carry the R. rickettsii bacteria: the American dog tick, the Rocky Mountain wood tick, and the brown dog tick.

RMSF is considered a rare disease, but according to Dr. Dana Hawkinson, an infectious diseases physician at the University of Kansas Hospital, rare is a matter of where you are.

“We in the Midwest are always concerned about tick-borne illnesses,” Hawkinson told Healthline.

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Not Always Noticeable

Ticks do not cause pain when they bite you. This makes it more likely that you will not notice when they do.

Most tick-borne illnesses have symptoms that are commonly associated with other conditions. RMSF is easy to treat, but people who don’t know they’ve been bitten might not suspect they’ve been infected.

“The main issue is getting evaluated and getting the correct medication.” Hawkinson said.

Doctors in states such as Missouri and Oklahoma, where RMSF cases are more common, are on the lookout for patients who may have been bitten and are experiencing symptoms related to a tick-borne illness.

RMSF is usually treated with the antibiotic doxycycline, which is also used to treat many other conditions including Lyme disease. Most people who receive treatment recover without any complications.

However, people who wait to start treatment are more likely to experience serious complications. The bacteria can cause blood vessels to leak or develop blood clots. This can lead to inflammation in the brain, heart, or lungs.

The Centers for Disease Control and Prevention (CDC) notes that most people who start doxycycline within five days of noticing symptoms see improvement within 24 to 72 hours. Since doxycycline became the first line of treatment for RMSF, Hawkinson says, “We have been able to prevent quite a bit of mortality.”

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When and Where

Tick-borne illnesses like RMSF are more common in the warmer months when people are more likely to be participating in outdoor activities.

People who are infected with RMSF often don’t develop symptoms until several days after being bitten. Ticks do not always leave noticeable bite marks on humans, but ticks burrow into their hosts and may stay attached for hours or days. Most people discover a tick has bitten them when they find it buried in their skin.

Ticks prefer to bite people in warm or moist areas, in particular the armpits, groin, or scalp.

Ticks are often found in places with overgrown grass or brush. You can prevent tick bites by avoiding areas with overgrown trees and grass.

If you are unable to avoid these types of areas, wear long sleeves and pants. You can also spray your skin with insect repellant that contains DEET, or treat your clothes with permethrin.

If you’ve spent time in a wooded or grassy area, you should wash the clothes you were wearing and take a bath or shower as soon as you get home. This will make it more likely that you will catch any ticks that have hitched a ride on your clothes or body.

You should also check any pets that spend time outside, as they can be bitten or bring ticks into the house.

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