Barbara Schroeder wasn't overly concerned when her daughter Julia, then 2, spiked a fever for a few days. "She said her head and body ached, and she slept a lot, but kids get viruses," Schroeder says. Julia improved, but then months later her knees became so swollen and inflamed she could barely walk. Because the family lives in York, Pennsylvania, an area with a high incidence of Lyme disease, a bacterial infection that's spread by certain ticks, Julia's pediatrician gave her a blood test for it. The test was negative, yet Julia's knees continued to ache, throb, and swell every few months. When she was 4, doctors believed she had juvenile rheumatoid arthritis. "But Julia didn't have the classic symptoms of juvenile rheumatoid arthritis," says Schroeder, who decided to take Julia to another doctor for more testing. By this time, she was 6, and the results left no doubt: Julia had Lyme disease.
"I never saw a tick or a rash," says Schroeder, referring to the reddish, bull's-eye-shaped rash called erythema migrans that's an initial telltale sign of the disease. But not all Lyme sufferers develop a rash -- and diagnostic tests for the disease aren't always reliable. In fact, Lyme is plagued with ambiguities.
No one's sure exactly how many people get infected with Lyme disease each year, though experts agree rates are going up. For decades, the Centers for Disease Control and Prevention (CDC) counted only confirmed cases of Lyme, but in 2008 broadened its criteria to include probable cases. As a result, the incidence of Lyme in adults and children skyrocketed 77 percent from 19,931 cases in 2006 to 35,198 cases in 2008. Even then, the actual number of people being treated for Lyme may be up to 10 percent higher. Doctors don't always report patients to their state health department, perhaps because diagnosis is so problematic. Lyme disease has become more of a problem over the years because the number of ticks, and the deer they feed on, have been increasing. Knowing which ticks cause problems -- and which symptoms to watch for -- is key to keeping your child healthy.
Ticks To Look Out For There are more than 800 species. But only black-legged ticks in the Northeast and upper Midwestern black-legged ticks along the Pacific carry the Lyme bacteria, called Borrelia burgdorferi, which they secrete into a child's bloodstream when they bite. Both kinds of black-legged ticks are commonly called deer ticks because they hitch rides and feed on deer; but they also feast on small animals like mice, which is where they tend to pick up Lyme bacteria. Your child's odds of being bitten by a Lyme carrier depend on where you live and where you visit. Half of the deer ticks in high-risk states (Connecticut, Delaware, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island, and Wisconsin) are infected with Lyme, compared with only 2 to 4 percent in Pacific states like California and Oregon. Very few black-legged ticks in the South are Lyme carriers because the bacterial infection isn't as widespread among mice in the region. Lyme-carrying ticks are most active in May, June, and July, according to the CDC, though you can get Lyme year-round.
Unfortunately, the ticks most likely to spread Lyme are incredibly hard to spot. Adult female deer ticks are red and black and about the size of an apple seed; males are black and a bit smaller. But during their nymph stage (what we might consider the teen years), they are brownish and tiny -- about the size of a poppy seed or a pinhead. "I tell parents to look for 'freckles' or 'moles' that weren't on their kids before -- that's how small these ticks are," says Penelope Dennehy, M.D., director of pediatric infectious diseases at the Hasbro Children's Hospital's Pediatric Lyme Disease Clinic, in Providence.