Wednesday, June 28, 2006

Lyme Q&A


Ah, summer. Time to get out of the house and into nature. And time to start watching for the tiny deer ticks that carry Lyme disease, says medical entomologist Richard Falco of Fordham University.

June and July are the peak season for Lyme disease because ticks are in their nymphal stage and are most active. Reporter Anita Manning interviews Falco and other experts who offer basic information on Lyme disease, a potentially dangerous illness:

Q: How do people get the disease?

A: The bacterium is transmitted by the bite of infected blacklegged ticks, also called deer ticks. It is not known to pass from one person to another, from a pet to a person, through blood transfusion or by eating infected deer or squirrels.

Q: Is the disease a concern only in the summer?

A: Lyme disease is reported year-round, but the majority of cases occur in the summer. The disease has been reported in nearly every state. About 20,000 cases are reported to the Centers for Disease Control and Prevention each year, a national average of nearly seven cases per 100,000. But in the 12 states where it is most common, the average was just over 27 per 100,000.

Q: What should I do to protect myself and my family?

A: If possible, avoid woods and tall grass. If not, the CDC advises using bug repellent containing DEET and doing frequent body checks. The nymphal ticks are tiny, about the size of a poppy seed, so it's important to look carefully, particularly on legs, arms and groin.

About 70 percent of Lyme disease infections are acquired around the home. "If you live in an urban area and go to the park once a month, you're likely be more diligent," Falco says. "But if you live in an area where there are ticks and there's risk just walking to the mailbox, it's difficult to take these precautions day in and day out."

Q: What can I can do around the house and yard to get rid of ticks?

A: Ticks need high humidity to survive, so remove leaf litter, keep grass short and cut back underbrush. In regions of high infestation, such as the Northeast, "chemical control is probably the least difficult and most effective way to control ticks in the suburban environment," Falco says. Spraying an insecticide in early June and again in the fall is "optimal."

Q: What are the symptoms, and how is the disease treated?

A: Symptoms vary, but about 70 percent of people develop a circular rash at the site of the bite after three to 30 days. The rash expands over days to as large as a foot in diameter, developing a bull's-eye appearance. Patients also have chills, fever, headache, fatigue, muscle and joint aches and swollen lymph nodes. Prompt treatment with antibiotics resolves most cases, but some people continue to have symptoms for months or years. Untreated, it can lead to chronic illnesses, including arthritis and neurological problems.

Q: Can my pets get it?

A: Dogs are very susceptible and can pick up ticks easily because they're low to the ground and love to roll around in grasses. Ticks apparently aren't as attracted to cats, so they're less vulnerable, says veterinarian Richard Ford of the College of Veterinary Medicine at North Carolina State University.

A dog carrying ticks poses a threat not only to itself but also to humans in the house. "The dog moved out of the doghouse a long time ago. People are sleeping with their pets," Ford says. Pet owners should apply topical tick repellent every month, and in areas where Lyme disease is common, dogs should be vaccinated each year.