Rocky Mountain Spotted Fever

What is Rocky Mountain spotted fever?

Rocky Mountain spotted fever is a disease that you can get from a tick bite. Sometimes it causes a very severe illness and can be fatal. Prompt treatment is important.

How does it occur?

This infection is caused by a type of bacteria called Rickettsia rickettsii. It is spread from the bite of an infected tick. It can also be spread by contact with a crushed tick or tick feces. The infection usually does not spread from a tick to you until after the tick has been attached and feeding on your blood for several hours.

Most ticks are not infected with the bacteria. Even in areas where there are a lot of infected ticks usually only 1 to 3% of the ticks are infected. This disease occurs throughout the United States during the months of April through September. You can also get the disease in southern Canada, Central America, Mexico, and parts of South America. Although this disease was reported most often in the Rocky Mountain area early after its discovery, relatively few cases are reported from that area today. Many more cases are seen in the Carolinas in and around the Blue Ridge Mountains. Oklahoma, Missouri, and Arkansas also have more cases than the rest of the US.

What are the symptoms?

The first symptoms may include:

• fever
• nausea and vomiting
• severe headache
• muscle pain
• lack of appetite.

A few days later you may start having a rash on your wrists, forearms, and ankles that is pink or red and spotted. You may also have:

• abdominal pain
• joint pain
• diarrhea.

The rash may spread to the palms of the hands, soles of the feet, and the trunk and abdomen. Although the rash is common, in 10 to 15% of cases there is no rash.

How is it diagnosed?

Rocky Mountain spotted fever can be hard to diagnose in its early stages. Your healthcare provider will ask about your symptoms and medical history, including recent exposure to ticks. He or she will examine you. You will have blood tests. There are specific tests to confirm the diagnosis but they take several days to complete. Treatment should not be delayed while your provider waits for results from these lab tests.

You may have a skin biopsy. Your healthcare provider will give you a shot of numbing medicine in an area where you have the rash. When the skin is numb, a small piece of skin with rash will be removed and sent to the lab. It may take several days to get the results of the skin biopsy, so treatment must be started before you get the results.

How is it treated?

You will probably stay at a hospital for treatment. You will be given antibiotics to kill the bacteria. Treatment for your symptoms (such as diarrhea) may include intravenous (IV) fluids and pain medicines.

This disease does not spread from person to person, so your family and friends do not need to be treated.

How long will the effects last?

If you are treated with antibiotics within the first 4 or 5 days of the infection, the fever and other symptoms usually start to get better after 2 or 3 days of treatment. If you are more severely ill or you were sick for a longer time before you got treatment, it may take longer to recover. Without prompt treatment the disease can be fatal.

How can I take care of myself?

Follow your healthcare provider's advice and take your medicine as prescribed.

How can I help prevent Rocky Mountain spotted fever?

To avoid getting Rocky Mountain spotted fever, follow these measures:

• Be aware of the areas where ticks live. Do not walk, camp, or hunt in the woods of tick-infested areas without precautions.
• In areas of thick underbrush, try to stay near the center of trails.
• When you are outdoors, wear long-sleeved shirts tucked into your pants. Wear your pants tucked into your socks or boot tops if possible. A hat may help, too. Wearing light-colored clothing may make it easier to spot the small tick before it reaches your skin and bites.
• Use approved tick repellents on exposed skin and clothing. Don't use more repellent than recommended in the package directions. Don't put repellent on open wounds or rashes. Don’t put it on your eyes or mouth. When using sprays for the skin, don’t spray the repellent directly on your face. Spray the repellent on your hands first and then put it on your face. Then wash the spray off your hands.
  • Adults should use products with no more than 35% DEET. Children older than 2 months can use repellents with no more than 30% DEET. DEET should be applied just once a day. Wash it off your body when you go back indoors.
  • Picaridin may irritate the skin less than DEET and appears to be just as effective.
  • Products containing permethrin are recommended for use on clothing, shoes, bed nets, and camping gear. Permethrin-treated clothing repels and kills ticks, mosquitoes, and other insects and can keep working after laundering. Permethrin should be reapplied to clothing according to the instructions on the product label. Some commercial products are available pretreated with permethrin. Permethrin does not work as a repellent when it is put on the skin.
• Treat household pets for ticks and fleas. Check pets after they've been outdoors.
• Brush off clothing and pets before entering the house.
• After you have been outdoors, undress and check your body for ticks. They usually crawl around for several hours before biting. Check your clothes, too. Wash them immediately to remove any ticks.
• Shower and shampoo after your outing.
• Inspect any gear you were carrying.
• Remove an attached tick with tweezers by gripping the tick as close to your skin as possible and gently pulling it straight away from you until it releases its hold. Don't twist the tick as you pull, and don't squeeze its body. Thoroughly wash your hands and the bite area and apply an antiseptic such as rubbing alcohol.
• If you spend much time hiking, you may want to include a pair of tick tweezers in your first-aid kit. The tweezers are available at many sporting goods stores.

For more information visit the Centers for Disease Control (CDC) Web site: http://www.cdc.gov.