Rocky Mountain spotted fever is a disease that you can get from a tick bite. Sometimes it causes a very severe illness.
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.
The first symptoms may include:
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:
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.
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.
You will probably stay at a hospital for treatment. You will receive antibiotics and treatment of your symptoms, which may include intravenous (IV) fluids and pain medicines. This disease is not spread from person to person, so your family and friends do not need to be treated.
If you are treated with appropriate antibiotics within the first 4 or 5 days of the infection, the fever and other symptoms usually begin to clear 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.
Follow your healthcare provider's advice and take your medicine as prescribed.
To avoid getting Rocky Mountain spotted fever, follow these measures:
DEET is a very effective repellent, but adults should use preparations with no more than 35% DEET, and children should use repellents with no more than 10% DEET. DEET should be washed off your body when you go back indoors.
Picaridin is another repellent recently made available in the US. It can be less irritating to the skin than DEET.
Some products containing permethrin are recommended for use on clothing, shoes, bed nets, and camping gear. Do not put permethrin on your skin.
For more information visit the Centers for Disease Control (CDC) Web site: http://www.cdc.gov.