Geography Is Important

Deadly Triangle: Deer, Mice, And Ticks
The Lyme disease organism has been found in about 50 species of birds and 30 kinds of animals. However, white-footed mice are major reservoirs of the causative Borrelia organism. White tailed deer are important as blood sources for adult ticks (hence the name Deer Tick), but the deer are not major reservoirs of the Lyme disease organism itself. Nevertheless, the fewer deer there are in an area, the fewer the ticks, and the lower the incidence of Lyme disease. As the deer become more abundant, deer ticks follow, and this is a major cause of the rise in Lyme disease cases.

You should be concerned about deer ticks and Lyme disease if all 3 of the following conditions prevail:

1. You live in either of the two regions where deer ticks are prevalent.

2, Deer are common within a mile of your home, or you visit areas, such as woods, parks or meadows, commonly frequented by deer; and

3. It is the right time of year (April to August) for most deer tick contacts.

Where Deer Ticks Live
While Lyme disease has been reported in 47 states, 85% of all cases of Lyme disease caused by deer ticks are clustered in two regions: the Northeast, from Pennsylvania to Massachusetts, and the upper Midwest in Wisconsin and Minnesota. New York has the highest incidence of deer ticks and Lyme disease of any state in the country, and in Westchester and Suffolk counties 30% to 80% of the deer tick population may be infected with Lyme disease bacteria.

Deer ticks are usually picked up when dogs or people roam into woods, brushy areas, or meadows with abundant seed-producing vegetation that feeds mice and other rodents that are common tick hosts. Ticks seem to prefer areas where green cover is available year round, such as honeysuckle, conifers, and pachysandra. Adult ticks are commonly found in the spring in their waiting positions on grass and low brush. Nymphs wait on the undersides of leaves or in leaf litter on the ground, where they attach themselves to passing mice and other small animals. Vegetable gardens are suspect because they attract deer; in heavy tick areas, vegetable gardens very often have ticks. Mowed lawns on the other hand seldom are home for ticks.

How to Find Deer Ticks
If deer ticks are so darned small, how can you find them before they find you? Easy—“flag” them down! Attach a 1-square-yard piece of white flannel cloth to a stick or dowel that is 4 to 5 feet long, so it looks like a white flag. As you move along the borders of your yard in high-risk areas such as paths, brushy borders, high grass, woodlot edges, and so forth, brush the “flag” against the vegetation ahead of you as you walk, moving it slowly up and down from ground level to about waist level. Alerted by movement, the nymphs will jump onto the cloth. Check your flag for hitchhiking ticks every few minutes. Pick the ticks off the cloth and drop them into a jar of soapy water or rubbing alcohol to kill them, or, if necessary, dump the whole flag into a container of soapy water instead. Later, launder the cloth to clean it for the next use. Be sure you are dressed protectively for the job, as we explain later in this file. Remember that “flagging” does not control ticks, it is only a way to discover if your area is tick-infested.

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