More than a dozen tick-borne diseases from a variety of ticks
have been identified in the US alone. Some you’ve heard of—Lyme disease
and Rocky Mountain spotted fever—while some are less
familiar—babesiosis, anaplasmosis, and Heartland virus.
The most common is Lyme disease, caused by a spiral-shaped bacterium,
or spirochete, called Borrelia burgdorferi. While the incidence of Lyme
disease is rapidly growing, the good news is that most tick bites can
be prevented or treated.
What kind of ticks should I watch out for?
Black-legged Ixodes ticks carry the Lyme disease bacterium and like
to feed off various animal hosts. The highly infectious young nymphs
prefer the white-footed mouse while the larger, less infectious adults
have a predilection for deer. Since these animals live in wooded areas
with tall grass, you should avoid these places.
How do I prevent tick bites?
The first step is to avoid wooded areas, but if you’re a hiker or
camper, minimize your risk by walking in the middle of paths and trails.
Use insect repellent containing 20 to 30 percent DEET on all exposed
skin and clothing, tuck pant legs into your socks, and wear long-sleeved
shirts. Clothing treated with 0.5 percent permethrin, another
repellent, will stay effective through several wash and dry cycles. And
don’t forget your pets. Not only are pets susceptible to many diseases
from ticks, they can also bring ticks into your home. Talk to your
veterinarian about monthly flea and tick repellent treatments and if you
have a yard, treat it with acaricides. One spraying in late spring will
reduce the number of nymphs, and another in October will reduce adult
ticks.
Don’t miss Protect Yourself from Poison Oak, Poison Ivy, and Poison Sumac.
What if I find a tick on my skin?
Don’t panic—not all ticks are capable of spreading Lyme disease.
Ixodes nymphs are the size of a poppy seed and have black legs while
adults are much larger, often a half inch long. The good news is that
because the Borrelia spirochete lives in the midgut of the tick, and it
takes at least 36 hours for the spirochetes to migrate to the tick’s
salivary glands. Therefore, it’s very rare to get Lyme disease unless
the tick is attached to your skin for at least 36 to 48 hours. In most
cases of Lyme disease, the evidence suggests that the tick was attached
for at least 72 hours.
No matter how long the tick has been attached, you want to get it
off. Use tweezers or small forceps (or your fingers if no other tool is
available), grasp the tick close to the skin and pull up firmly with
steady pressure—no squeezing or twisting, which could push more saliva
into the wound. Disinfect the skin and wash your hands with soap and
water. If it looks like parts of the mouth are still in your skin, don’t
worry—these aren’t dangerous and your body will expel them.
What do I do after I’ve been bitten?
If you know the tick has been attached for less than 36 hours, you
have little concern. If it has been longer or you’re not sure, there are
a couple of options:
Antibiotic Therapy
In carefully prescribed situations, you can take a single dose of doxycycline (200 mg), an antibiotic. This can significantly lower the risk of Lyme disease, but only makes sense if all of the following conditions are met:
- The tick is a nymph or adult Ixodes tick
- You know it has been attached for more than 36 hours and you can take the doxycycline within 72 hours of it being removed
- At least 20 percent of ticks in your area are infected with the Borrelia spirochete (this is the case in much of New England, the Mid-Atlantic states, Wisconsin, and Minnesota)
- You don’t have any conditions that prevent you from taking doxycyline (no other antibiotic will work)
Watch and Wait
More commonly, even in persons who meet all the criteria above, a
watch and wait approach is fine. For the next 30 days keep an eye on the
bite site for a rash and any flu-like symptoms (fever, muscle aches,
etc). The typical Lyme disease rash, called erythema migrans, is usually
painless and expands slowly over several days to resemble a bull’s-eye.
A simple, small red lesion at the site of a tick bite is normal and
doesn’t necessarily mean you have Lyme disease.
What do I do if I think I have Lyme disease?
If a rash or flu-like symptoms develop, see your healthcare provider.
But don’t worry—diagnosed at this stage, Lyme disease is essentially
100 percent curable with antibiotic therapy.
Not every Lyme rash has all the classic features, so don’t hesitate to have your healthcare provider check it out if you’re unsure.
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