Tick Bites

Ticks are nasty, blood-sucking critters that can transmit a variety of illnesses when they attach themselves to humans and bite. Over several days their body engorges itself with blood until they get so large that they detach themselves or fall off. Their bite is painless and often goes unnoticed until a lump is felt.

Ticks are a notorious transmitter of serious diseases. The three best known and most common are: Rocky Mountain Spotted Fever, Ehrlichiosis and Lyme Disease.

Rocky Mountain Spotted Fever (RMSF)

The only "Rocky Mountain High" in this illness is the degree of fever. Although first described in the Rocky Mountains, this illness occurs in any wooded area, and, in fact, most cases occur in the Southeastern United States. The germ transmitted by the tick is a rickettsia, a special type of bacteria. These organisms have a life cycle that involves an animal species as a host, and we are accidental victims.

Symptoms usually begin about a week after a bite from a tick carrying this bacteria. The illness starts abruptly with fever, aches, chills, nausea and vomiting. Affected individuals look and feel seriously ill. Several days later the characteristic rash appears. Classically, the rash is first noticed around the wrists and hands and spreads to involve the whole body within hours. Although initially flat red bumps, the involved areas become bumpy as the disease progresses. More serious involvement includes the presence of tiny pinpoint hemorrhages called petechiae. Characteristically, the rash involves the palms and soles.

This very serious disease can last weeks. Involvement of the nervous system, heart, lungs and other vital organs is frequent. Shock and death can result.

Ehrlichiosis

Ehrlichicsis exists in two forms in humans. The first documented form is called Human Monocytic Ehrlichiosis (HME) and was discovered in the late 1980s. The germs causing these illnesses (Ehrlichia) are related to rickettsiae. They only live in animal cells, and we become accidental victims when ticks infected with this organism bite.

Human monocytic ehrlichiosis infection is usually symptomatic. The most common symptoms one to three weeks after the tick bite are fever, headache, body aches, vomiting and lethargy, similar to a viral flu-like infection. A variable appearing rash occurs in 30-50 percent of infections about one week after symptoms begin. This form of Ehrlichlosis is usually much milder than Rocky Mountain Spotted Fever and lasts one to two weeks before disappearing. Occasionally much more serious illness, including life threatening problems, occurs. Laboratory diagnosis is difficult. Specific antibiotic therapy appears to be helpful.

Lyme Disease

First noted in the Lyme, Connecticut region in the 1970s, this bacterial infection has now been reported in 48 states. Most cases are reported in the Northeastern United States, forested Midwest and forested West Coast. Once again we are accidental victims of an infected tick. The tick's usual host is the white footed mouse. It spends its immature development on this rodent. This is the tick stage most likely to transmit Lyme Disease. The adult ticks preferred host is the white-tailed deer although human transmission can occur in this stage.

Infection with this bacteria (called Borrelia burgdorfen) is generally divided into two stages: early disease and late-stage disease. Early disease is itself divided into two overlapping stages.

The early stages of Lyme disease is usually marked by one or more of the following symptoms:

• fatigue
• chills and fever
• headache
• swollen lymph nodes
• a characteristic skin rash, called erythema migrans (EM)**.

**Erythema migrans (EM) is a red circular patch that appears usually three days to one month after the bite of an infected tick at the site of the bite. The patch then expands, often to a large size. Sometimes many patches appear, varying in shape, depending on their location. Common sites are the thigh, groin, trunk and the armpits. The center of the rash may clear as it enlarges, resulting in a bulls-eye appearance. The rash may be warm, but it usually is not painful. Not all rashes that occur at the site of a tick bite are due to Lyme disease (i.e. an allergic reaction to tick saliva at the site of the bite which can be confused with the rash of Lyme disease). Allergic reactions to tick saliva usually occur within a few hours to a few days following the tick bite, but usually do not expand and normally disappear within a few days.

Some symptoms and signs of Lyme disease may not appear until weeks, months, or years after a tick bite:

• Arthritis is most likely to appear as brief bouts of pain and swelling, usually in one or more large joints, especially the knees.
• Nervous system abnormalities can include numbness, pain, Bell's palsy (facial paralysis which usually occurs on one side) and meningitis (fever, stiff neck, and severe headache).
• Frequently, irregularities of the heart rhythm occur.
• In some persons the rash never forms; in some, the first and only sign of Lyme disease is arthritis, and in others, nervous system problems are the only evidence of the disease.

Lyme disease is often difficult to diagnose because its symptoms and signs mimic those of many other diseases. The fever, muscle aches and fatigue of Lyme disease can easily be mistaken for viral infections, such as influenza, infectious mononucleosis or chronic fatigue syndrome. Joint pain can be mistaken for other types of arthritis, such as rheumatoid arthritis, and neurologic signs can mimic those caused by other conditions, such as multiple sclerosis. At the same time, other types of arthritis or neurologic diseases can be misdiagnosed as Lyme disease.

Diagnosis of Lyme disease depends upon:

• Exposure to ticks, especially in areas where Lyme disease is known to occur. If your child has been bitten by a tick, always save it - correct identification and testing can confirm the presence or absence of the Lyme disease spirochete within the tick.
• Symptoms and signs as described above.
• The results of blood tests used to determine whether the patient has antibodies to Lyme disease bacteria. These tests are most useful in later stages of illness, but even then they may give inaccurate results, because laboratory tests for Lyme disease have not yet been standardized nationally.
• Consultation with your child's doctor.

Treatment

Lyme disease is treated with antibiotics under the supervision of your child's doctor. Several antibiotics are effective. Usually they are given by mouth but may be given intravenously in more severe cases. Children treated in the early stages with antibiotics usually recover rapidly and completely. Most youngsters who are treated in later stages of the disease also respond well to antibiotics. Rare, indirect deaths from Lyme disease have been reported.

Prevention

Prevention of Tick-borne illness include:

• Removing leaves and clearing brush and tall grass around houses and at the edges of gardens may reduce the numbers of immature ticks. This is particularly important in the eastern United States, where most transmission of Lyme disease is thought to occur near the home.
• A relationship has been observed between the abundance of deer and the abundance of deer ticks in the eastern United States. Consequently, removing vegetation that attracts deer and constructing physical barriers may help discourage deer and attached ticks from coming near the house.
• Applying acaricides (chemicals that are toxic to ticks) to gardens, lawns, and the edge of woodlands near homes is being done in some areas, but questions remain regarding its effectiveness and environmental safety. Application to residential properties should be supervised by a licensed professional pest control expert.

Personal protection

• Avoid tick-infested areas, especially in May, June and July (many local health departments and park or extension services have information on the local distribution of ticks).
• Wear light-colored clothing so that ticks can be spotted more easily.
• Wear long pants and tuck the pant legs into your socks or boots-, wear a long-sleeved shirt and tuck it into your pants; and use a hat for added protection.
• Tape the area where pants and socks meet so that ticks cannot crawl under clothing.
• Spray insect repellent containing DEET (products shouldn't contain any more than 30 percent DEET) on clothes, or treat clothes (especially pants, socks, and shoes) with permethrin, which kills ticks on contact. Remember that these products should be used with caution.
• Walk in the center of trails to avoid overhanging grass and brush.
• After being outdoors, remove your clothing and wash and dry it at a high temperature.

Inspect your child carefully and remove any attached ticks. For tick removal: grasp the tick with fine tweezers as close to the skin surface as possible, pull straight up with a slow, steady force and avoid crushing the tick or slipping off the body. Ultimately you do not want to force any material from the tick into your skin. Clean the area of tick attachment with disinfectant. Ticks (saved in a sealed container) can be submitted to certain local health departments for identification.

These tick bite associated illnesses are all serious. They are also treatable if diagnosed early in the disease. However, since many of the initial symptoms resemble common flu or viral infections, the history of a preceding tick bite, or even the history of having been in a forested area during tick season, could be important in making the correct diagnosis. Therefore, if your child becomes ill in the weeks after a tick bite, make sure you tell this crucial information to your physician.