Tame your tick phobia

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Free yourself from fear of Lyme disease

Red alert: As you read this, an army of tiny eight-legged parasites is spreading a mysterious disease and causing widespread panic. Don't go outside, lock up the kids and cancel the picnics. This warning seems like it could come right out of a bad 1950's sci-fi movie. But it actually reflects the way Lyme disease--an inflammatory illness spread by ticks--is often perceived by the public. But the fact is, most of us have little to worry about when it comes to contracting this illness. "The actual risk of getting the disease as perceived by most people is far out of proportion to their real risk," says Robert T. Schoen, M.D., co-director of the Lyme disease clinic at Yale University School of Medicine. "Many people are needlessly anxious and frightened about an illness when they really shouldn't be."

That's because Lyme disease is no common cold. To be at risk, you must be in a specific part of the country at a certain time of the year and come into contact with a specific type of tick that's carrying a certain kind of bacteria. That's a lot of maybes.

Still, let's say you meet those requirements. "Even people who are bitten by ticks known to carry the Lyme disease bacteria are at low risk. How low depends on how long the tick has been attached," says David T. Dennis, M.D., from the Centers for Disease Control and Prevention, Division of Vector-Borne Infectious Diseases, Fort Collins, Colorado. One study, in an area where Lyme disease is endemic, showed a risk of less than 5 percent in people who identified and removed the tick (New England Journal of Medicine , December 17, 1992).

"The risk of infection is low as long as you find and remove the tick. Studies (on mice exposed to ticks that fully feed) have shown that if the tick isn't found and removed within 36 hours--which happens in most cases of Lyme disease--it will transmit the bacteria, and the risk jumps to 20 to 30 percent," says Durland Fish, Ph.D., associate professor of community and preventive medicine and director of the Lyme-disease center at New York Medical College in Valhalla. And if it's not cured early, it could turn from a relatively mild infection into something far more serious.

The point is this: Although there's no need to get yourself into a tick tizzy, you should be tick smart. "The most potent tool for avoiding Lyme disease is knowledge," says Dr. Dennis. "A heightened awareness of how and where it is spread, along with knowing how to avoid exposure, will greatly help to reduce your chances of getting the disease."

Here we offer simple, straightforward answers to your toughest questions concerning this illness. If you want to know your true odds of getting Lyme disease in various situations, how to prevent it or cure it if you ever do get infected, read on.

Where is Lyme disease a problem? Wherever you're most likely to find the ixodes tick, the tick responsible for spreading the disease. Lyme disease is caused by a bacterium called Borrelia burgdorferi, carried by two main ixodes ticks: the blacklegged tick (commonly known as the deer tick) in the East, and the western blacklegged tick. (By the way, these buggers aren't just found on deer, but also on rodents, other small mammals, some birds and even reptiles.)

You'll find the real tick-rich states along the northeast and the upper north-central regions of the United States--Connecticut, Delaware, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, Rhode Island and Wisconsin. A few cases have been reported now by nearly every state, and experts believe it is spreading. (See the state-by-state case reports on page 90.) More than 50,000 cases have been reported since 1982.

If you live in one of these riskier states but spend most of your time in a downtown high-rise, your risk may be close to zero. If you live, work or hike in wooded areas, you may be tramping through tick heaven. Ticks thrive in humid, deeply wooded, densely brushed areas. Because the tick population varies depending on the time of year, so does risk. Roughly 80 percent of Lyme-disease cases occur from May to August, when nymphal ticks are active.

How many ticks actually carry the bacterium? The percentage varies. In northeastern states heavily populated with black-legged ticks, 25 to 50 percent of these ticks may be infected. Less than 5 percent of the western blacklegged ticks carry the bacteria in West Coast states.

"One hot spot for Lyme disease is Westchester County, New York, where populations of ticks and people are high; 25 to 50 percent of ticks there have the organism," says Dr. Fish.

But in many areas, the chance that an ixodes tick is infected is considerably less--in the range of 1 to 3 percent. In southern regions, tick infestation is localized along the coast and offshore islands of Georgia, Florida and coastal areas of North Carolina and Virginia. "The risk is much lower there because the tick infection rate is generally under 2 percent and the number of ticks is considerably smaller," says Dr. Dennis.

What should I do if I find a tick on me? There's little risk involved if the tick is nabbed within 36 hours. After 36 hours of attachment, the risk jumps.

To remove a tick correctly, take a pair of tweezers with very thin ends, grasp the tick as close as possible to your skin (at its mouthparts) and slowly pull the tick straight out. "Pull straight back gently, but firmly, using an even, steady pressure," says James E. Keirans, Ph.D., curator of the U.S. National Tick Collection at the Institute of Arthropodology and Parasitology, Georgia Southern University, in Statesboro. Don't jerk or twist it. Be careful not to squeeze the body or you may inject the contents of the tick into your body. It's helpful to save the tick for later identification. If you become ill, be sure to tell your doctor you've been bitten by a tick so he can check for tickborne illness.

"You'll probably leave some mouthparts in your skin," says Dr. Schoen. "Some patients will come to see me after needlessly digging into their skin. Just treat it like a thorn and let it work its way out." After removal, disinfect the skin and wash your hands with soap and water.

How can I tell if I have Lyme disease? Because most infection-causing bites go unrecognized by the victim, you'll have to rely on symptoms. "Only about 20 percent of the people who get infected actually remember being bitten," says Dr. Dennis. That's because the tiny, nymphal ticks are doing most of the infecting, and they're hard to see and feel. (Although proportionally more adult ticks are infected, disease transmission rates are higher for nymphal ticks.)

Experts divide the disease into early and late stages--each with its own symptoms. The late stage is much more serious--that's why it's important to nab the disease early.

After the bite, it takes 3 to 30 days for the slowly replicating bacterium, also known as a "spirochete," to start causing symptoms. Your most noticeable symptom is a rash--characteristically a slowly expanding "bulls-eye" known scientifically as erythema migrans. (See page 90.)

These rashes occur in roughly 60 to 80 percent of Lyme-disease patients, most often accompanied by flulike symptoms--fatigue, fever, headaches, chills, stiff neck and aches in muscles and joints. Sometimes, however, you may have only the flulike symptoms, or no symptoms of early disease at all.

The later stages can begin within weeks to months. As the germ spreads, you may have pain in the joints, tendons, muscle or bone. Partial paralysis of the face, as well as heart palpitations, may occur. Arthritis--usually in the form of a swollen knee--can strike in intermittent attacks. The symptoms may come and go.

If the disease isn't caught and cured in the early stages, the symptoms may become chronic; they would include knee arthritis, which becomes more constant. This late stage may drag on for months or years.

If I don't get treated for early-stage infection, what are my odds for getting late-stage disease? Pretty high. Before there was a cure, 60 percent of the folks who had the initial rash and weren't treated in months or years would go on to develop the late-stage arthritis. About 15 percent developed neurologic signs--sometimes serious enough to cause cognitive problems. "That underscores the importance of early treatment. Lyme disease can cause serious and sometimes disabling problems if it's missed," says Dr. Dennis.

If I experience symptoms, and I think I have Lyme disease, what should I do? See your doctor first. He or she may have you undergo testing or refer you to someone who has more experience diagnosing the disease.

"It's important to ask your primary physician if he has seen a lot of Lyme-disease cases and has kept up on the current research," says Dr. Schoen. Just as important, because your blood must be sent off for an accurate diagnosis, your doctor should be working with a competent lab. "The doctor and lab go together," says Dr. Schoen. Because testing is new and hasn't yet been standardized, variability among labs exists. "That's why you should ask your doctor how much confidence he has in the lab he uses," says Dr. Schoen. "And if you live in an area where the disease is rare and your doctor has seen few, if any, cases, have him refer you to someone else."

How is Lyme disease diagnosed? The most commonly used laboratory test that doctors use to diagnose the disease is called the ELISA test (Enzyme-Linked Immunosorbent Assay), a blood test that measures the antibody (a type of protein) that the patient makes to fight the bacterium. Because the antibody response in Lyme disease starts slowly and increases over time, the test may be negative during the first several weeks of infection.

"If you test a person at the time they have the rash, only 30 to 40 percent would be positive," says Dr. Dennis. In six weeks to two months, though, about 60 percent of the patients would test positive. "But because the rash is so characteristic of the disease, even if the test is negative we often treat patients based on that symptom alone," he says. In late stages of disease, the test has 90 percent accuracy.

ELISA is the most widely used test, but other tests doctors use may not be as useful. Because testing protocol varies across the country, the Centers for Disease Control and Prevention is working on standardizing testing along with other centers. "We're developing a two-step approach we expect many laboratories will be following soon," says Dr. Dennis.

The protocol begins with the ELISA. If that doesn't give an absolute yes or no answer, then a test called a Western blot is used for clarification. There the proteins of the bacterium are separated and the immune response to each one is determined. "We think this is a reliable, sensitive test that will overcome the variability that occurs in most labs," says Dr. Dennis. Look for this to become a regular practice within the year.

What is the treatment for Lyme disease? For early-stage disease, the treatment is almost always oral antibiotics--usually doxycycline (a form of tetracycline) or amoxicillin--given for two to four weeks. "The cure rate is 95 percent," says Dr. Schoen.

For the later stages, antibiotics are still the only treatment--given for three to four weeks, sometimes intravenously in the form of ceftriaxone or penicillin G. "Most patients can be treated successfully at this point--with 85 to 90 percent returning to normal function within a year," says Dr. Schoen. A small proportion may have illness afterward, which may not be due to the continuing infection, he says. Drug side effects are usually minor, but use of IV antibiotics may in some cases cause serious complications like bloodstream infection and gallbladder disease, says Dr. Dennis.

If your child becomes infected, the treatment is nearly the same. "Because tetracycline and doxycycline--standard treatments for early-stage disease--can stain the teeth in children nine years and under, though, doctors will substitute other antibiotics for those drugs," says Dr. Dennis. Doses would be smaller than for adults.

I've heard about patients who get antibiotics for a lot longer than one month. Is that safe? "There is no published research to back this treatment, and it shouldn't be done," says Dr. Schoen. Although some doctors use long-term antibiotics for months on end, treatment for late-stage disease should be stopped in nearly all cases after 28 days.

But aren't there times when some people don't respond to treatment? In a small percentage of people, antibiotic therapy may not kill off the germ completely, and retreatment may be necessary. But this is rare.

Misdiagnosis is the most common reason patients with presumed Lyme disease don't respond to therapy. In a study of 788 patients being treated for Lyme disease at one clinic, for example, only 23 percent had the active disease (Journal of the American Medical Association , April 14, 1993). There may be a strong chance, then, that the patient's lack of response may be due to misdiagnosis. "Misdiagnosis is a real problem for something as new as Lyme disease," says Dr. Schoen. Again, this underscores the importance of standardized testing, as well as seeking out a doctor who treats many Lyme disease cases and keeps up to date on the latest research.

Should I get treatment right after I'm bitten by a tick, before symptoms show up? The risk of Lyme disease is small after a tick bite, especially if the bugger is quickly removed. So in most tick-bite scenarios, most doctors employ a wait-and-see approach to see if any symptoms develop before giving treatment.

Doctors in high-risk areas, however, may decide whether to treat on an individual basis. "A lot of factors have to be addressed beyond the length of attachment," says Dr. Dennis. "For example: Was she able to retrieve the tick, and did we find out if this is the type that carries the bacterium? If so, is the tick from an area where a high proportion of ticks are infected?" If you meet these criteria, then your doctor might prescribe a short course of antibiotics.

In the meantime, how can I prevent tick bites? "The most important thing you can do is avoid places of tick exposure at times when they're most prevalent," says Dr. Dennis. If you're going on a picnic, a hike or a barbecue in an area where you will be exposed (it may even be in your own yard), here are some key steps you can take:

Clothing: Keep the colors light so ticks can be spotted when they get attached. Tuck your pants into your socks and wear long-sleeved shirts to make it tough for the tick to get to the skin.
Checking: Set up regular, daily tick checks for you and your family. Have each other check for ticks and promptly remove any that are found. "That will greatly reduce the risk of becoming infected even if you are bitten," says Dr. Dennis. You'll also need to recognize the tick. The blacklegged tick in its youngest, most dangerous stage is much smaller than the common dog tick or wood tick.
Landscaping: Reduce your risk by removing brush or shaded, leaf-littered and wooded parts of your property. Or just open those areas up to more sunlight. "That makes the environment less favorable for ticks and for the rodents that carry the Lyme disease germ," says Dr. Dennis. Most ticks get the germ from rodents. Any places that provide harbor for these critters--wood piles and rock walls--should be removed or pushed back on the property. Removing bird feeders may help as well. They also attract the germ-carrying mice.
What about repellents? If you're entering a tick-heavy area, skin or clothing repellents can offer protection. Permethrin (brand names: Permanone and Duranon) is an effective insecticide for clothing; repellents with deet (N,N-diethyl-meta-toluamide) are effective for both skin and clothing.

"For routine exposure to ticks, permethrin on your clothing is very effective, but it's not for use on skin," says Dr. Fish. You should follow the directions closely and immediately wash any skin exposed to the product.

"For occasional exposure--if you're hiking in the woods, for example--and you don't want to cover yourself completely with clothing, then you ought to use deet," says Dr. Fish. For long-term exposure in tick-heavy areas, deet plus a permethrin-containing formula may be the best protection. "Long-term studies strongly suggest these products are safe and nontoxic," says Dr. Fish. Permethrin for clothing, however, is still not approved for sale in California.

What about insecticides for lawns? Who should use them? Residential areas aren't hotbeds of tick life. But they can be. Take Westchester County, New York--one of the hubs of tick activity. The highest risk of exposure is on residential properties (lawns, gardens and woods) and their surrounding areas. One study reported that 36 to 60 percent of properties surveyed had infected ticks--suggesting that regularoutdoor activities like gardening or mowing the lawn may put these homeowners at some risk.

The decision to use insecticides, of course, greatly depends on where you live. "If you happen to live near the woods or have lawns adjacent to woods located anywhere from Maryland to Boston, you may be living with blacklegged ticks. If you see ticks on your clothing, on children or on pets, or if your neighbors are complaining about a problem, then the prudent course of action may be to apply lawn insecticide," says Dr. Fish.

Three insecticides have been found to reduce tick infestation by 70 to 97 percent: chlorpyrifos (brand name: Dursban) or carbaryl (Sevin), which are available in liquid or granular forms at garden-supply stores; the other type, cyfluthrin (Tempo), is an insecticide available only from professionals in pest control.

Granular forms of insecticides are the easiest to use and can be applied like fertilizer to lawns and ornamental ground where people walk.

You'll need only two applications each year to do the trick. "One spray the first of June will eradicate 90 percent of ticks in the nymphal stage and another spray in late September will lead to an 80 percent reduction in remaining adult ticks," says Dr. Fish.

But are they safe? For a pesticide to kill ticks, it must be toxic to the tick. But just because a substance can kill an insect does not mean it's harmful to us. The tremendous difference in body weight between ticks and other animals or humans ensures safety if you follow label directions carefully.

"The pesticides mentioned above have all undergone tests for long-term and acute toxicity and have been registered by the Environmental Protection Agency as safe when used according to their label directions," says Dr. Fish.

PHOTO: A woman walking in a field.

PHOTO: How do you know if a tick transmitted the bacterium? The most noticeable symptom may be a 'bull's-eye' rash that appears in 3 to 30 days.

MAP: Number of cases of lyme disease reported by states to the CDC in 1993*

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By Greg Gutfeld with Linda Rao

TICKS COMMONLY FOUND IN THE UNITED STATES
Ixodes scapularis, blacklegged tick Ixodes scapularis nymph Ixodes pacificus, commonly known as the western blacklegged tick
Rhipicephalus sanguineus, brown dog tickHaemaphysalis leporispalustris

Dermacentor andersoni, Rocky Mountain wood tick; carries Rocky Mountain spotted fever

Dermacentor variabilis, American dog tick

Amblyomma americanum, Lone Star tick

Ticks in red (bold) may carry Lyme disease

ILLUSTRATIONS: Showing size of the ticks and what they look like.

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