Welcome to the Year of the Tick

Sunday, March 11, 2012  By Scott Shalaway Post-Gazette

Have you heard of an increase in the deer tick population this year?" writes Dave Fahrner of Pittsburgh. "Last fall my dog and I came home from several outings, and I picked many ticks from each of us. I haven't seen as many ticks in my entire life as I have recently. Have you heard similar reports?"

Yes, I've had several phone calls and emails about ticks. This is shaping up to be a big tick year, thanks to the unusually mild winter. A good hard winter usually controls ticks that overwinter in egg or larval form. This year we just have not had that prolonged big freeze.

The dog and deer tick life cycles require three hosts and can take several years to complete, depending on the supply of hosts. Adult females lay eggs in the fall. The eggs that survive winter hatch in the spring. Tiny six-legged larval ticks work their way to the tips of ground vegetation. There they wait, sometimes for months, and "quest" for a small mammal, usually a deer mouse.

The larval tick holds onto the grass with its rear legs and with its outstretched front legs waits for a mouse to wander by. When it hitches a ride, it quickly attaches to a thin piece of skin for its first blood meal.

The larva then drops to the ground and molts into an eight-legged nymph stage and waits for its next host, usually a medium-sized mammal, such as a raccoon or fox. After hitching another ride and enjoying another blood meal, the nymph drops off and molts into the eight-legged adult tick.

The adult then waits for a deer or human to wander by. This host provides the blood that enables female ticks to manufacture up to 4,000 eggs. After depositing the eggs on the ground, the female dies.

Fortunately, most eggs do not usually survive the winter, and most immature ticks fail to find all three required hosts, so they starve. Enough, however, survive to make life miserable for humans and dogs.

The black-legged or deer tick (Ixodes scapularis) carries the bacterium (Borrelia burgdorferi) that causes Lyme disease. It is smaller than the more familiar dog tick. The bacterium circulates harmlessly in the blood of deer and other mammals and can be transmitted to humans after an adult deer tick acquires it in a blood meal from a deer or an earlier host.

The best treatment for Lyme disease is prevention. Wear repellent. Tuck pant legs into socks and wrap them in duct tape. Do frequent tick checks. Shower after being outdoors.

If you find an attached tick, here's what the Centers for Disease Control and Prevention recommends: Use fine-tipped tweezers to grasp the tick as close to the skin's surface as possible. Pull upward with steady, even pressure. Do not twist or jerk the tick. If the mouthparts break off, remove them with the tweezers. Then clean the area with rubbing alcohol and soap and water. If after finding an attached deer tick, you discover a telltale bull's eye rash or develop symptoms such as fever, chills or achy muscles, see a physician.