Rocky mountain spotted fever (RMSF) is a widespread infection that occurs throughout the continental United States. It is caused by Rickettsia rickettsii bacteria. Although the name implies that the disease is related to the Rocky Mountains, it is most commonly seen in the southeastern and south central states. The disease is spread to humans through the bite of an infected tick. Most often, the infected tick is a dog tick, but sometimes it can be a wood tick. Cases tend to occur from April through September. The disease most often affects children and teenagers younger than 15 years, especially those who spend time outdoors or have pets that might carry the ticks.
Signs And Symptoms
Children infected with RMSF first have symptoms common to many other infectious diseases, including flu-like symptoms such as fever, muscle pain, severe headaches, vomiting, nausea, and loss of appetite. A rash develops in most cases of RMSF, typically before the sixth day of the illness. This rash tends to appear first on the wrists and ankles, but within hours it can spread to the torso. It can also spread to the palms of the hands and soles of the feet. The rash is red, spotted, and raised. Other symptoms may include joint pain, stomach pain, and diarrhea. In severe cases, the blood pressure can drop and the patient may become confused. As the infection spreads, many organs, including the brain, can be affected. Laboratory findings include low platelet counts and a low sodium level.
Symptoms usually appear about 1 week after the tick bite occurs. This incubation period, however, can range from 2 to 14 days.
When To Call Your Pediatrician
If your child has been exposed to ticks or you know she has been bitten by a tick, contact your pediatrician if your child develops any of these symptoms.
How Is The Diagnosis Made?
Your pediatrician will evaluate your child’s signs and symptoms and also use blood tests to confirm the diagnosis of RMSF. Laboratory findings that could help identify RMSF include decreased blood platelet count (thrombocytopenia), decreased concentration of sodium in the blood (hyponatremia), and increased level of liver enzymes (elevated transaminases).
If your pediatrician suspects that your child has RMSF, the doctor will prescribe a course of antibacterials to be started immediately. Most often, doxycycline is the drug chosen to treat RMSF. Treatment with this medication usually continues for 7 to 10 days or until the child’s fever has been gone for at least 3 days. Although doxycycline and other tetracycline antibiotics are not normally used in children younger than 8 years, in this case, the need for treatment of the bacteria outweighs the small risk of staining the teeth. The other antibacterial used to treat RMSF is chloramphenicol. This drug is avoided when possible because of possible side effects affecting bone marrow.
What Is The Prognosis?
With early treatment, almost all children will recover completely from RMSF. Even without antibacterial therapy, most children recover. However, the infection can become severe and overwhelming. Although rare, certain patients may have long-term complications that include nerve damage, hearing loss, incontinence, partial paralysis of the lower extremities, and gangrene that can lead to the amputation of toes or fingers. Some children may die from RMSF.
The best preventive measure is to keep your child away from areas where ticks are present, such as wooded areas and areas with brush and tall grass. If she spends time in tick-infested regions, apply an insect repellant containing DEET to her exposed skin, following product instructions. Do not use excessive amounts of DEET on children. Regularly inspect your child’s clothes and body for ticks, including the scalp and hair. If your child wears light-colored apparel, it will be easier to see ticks that may be crawling on her clothing. Don’t forget to check your pets for ticks. Ticks can be brought in to the house on the dog’s fur and spread to a child.
Antibiotics should not be taken as a preventive measure after a tick bite because the risk for infection is so low.