JUDY WOODRUFF:

The arrival of spring is a most welcome sight to many of us, but it also brings a serious health problem, ticks. They can lead to Lyme disease in humans, which can be a serious chronic condition.

Many suburban areas are trying to figure out just how to deal with an increasing number of ticks, which some blame on the growing population of deer in the U.S.

Researchers are enlisted in this battle as well.

Miles O'Brien has the story for our weekly segment on the Leading Edge of science.