While You're Away: Tick-Borne Diseases
For many years, ticks were the Rodney Dangerfield of the insect world... they didn't get any respect! But since the discovery of Lyme disease in Connecticut in the mid 1970's, they have finally gotten the attention they deserve. Though they are not responsible for as much morbidity or mortality as mosquito-borne infections such as malaria, ticks transmit a greater variety of organisms than any other group of arthropods.
Tick-borne diseases are ubiquitous. They are of concern to the New England backpacker (Lyme disease, Babesiosis), the couple on safari in South Africa (African tick typhus), the student spending the summer in the forests of Eastern Europe (Tick-borne encephalitis) and even the golfer in South Carolina (Erlichiosis). More than twenty-five different infections are passed worldwide by these innocent looking insects.
Ticks, much like ice cream, come in two varieties - hard and soft. They differ from each other mainly in appearance and their feeding habits. In temperate climates, ticks do their feeding from spring through fall, so the incidence of many of these diseases is seasonal.
When it comes to lunch, ticks can usually be found feeding on their animal hosts, such as dogs, deer, birds and rodents. It is when we veer off the beaten path in pursuit of mountain streams, big game or lost golf balls that we tend to end up as a tick's aperitif.
The skin is often the first site of a tick-borne infection. In Lyme disease, a bullseye-shaped lesion usually appears at the bite site. In Africa, a black "eschar" is often found. Fever and other flu-like symptoms are common to most tick-borne infections. Encephalitis, kidney failure, bleeding disorders and chronic arthritis are other potential and occasionally fatal complications. In travellers, these infections may mimic other tropical illnesses such as malaria, typhoid, dengue, and meningococcemia.
Ticks and the gifts that they bear can be avoided. If one must walk through wooded areas where ticks travel, cover up. Wear long pants and tuck them into your socks. Light coloured clothing is recommended. Insect repellents containing DEET should be applied to the skin, and permethrin containing repellents (Permanone) can be sprayed on clothing. This product may not be readily available in Canada. At the end of your day in the woods, examine yourself; or your friends, from bottom to top for embedded ticks.
Should you discover a tick having dinner by your ear, don't panic! It usually takes a couple of days of attachment before any infection is transmitted. Try to grab her (the tick) with a pair of curved forceps right at skin level, and apply gentle traction to extricate the tick from your skin. Be careful not to squish it in your bare fingers. A vaccine is available for the prevention of tick-borne encephalitis, a viral infection prevalent in Eastern Europe during the spring and summer months.