Even if you're careful, you can get lice. Playing with a friend's child can transmit the parasite to you. So can leaning against a theater headrest or borrowing a friend's headphones-although lice don't live for long away from a human host. Still, you can take steps to lessen your chances of getting lice.

Outbreaks of head lice are common in many elementary schools. You can't prevent your child from going to school or playing with other children. Even if you take every other precaution, your child may still get lice.

Lice can survive for two to three days away from a human body. It is easier for them to live on cloth than on hard surfaces such as metal or porcelain. You may catch lice from a carpet or chair; catching them from a toilet seat is unlikely.

Head lice can spread when people use each other's hats, brushes, or combs. Clothing, especially bathing suits and underwear, can spread pubic or body lice.

You can catch lice even if you use a condom or practice other safe sex habits. Having sex with people who have many partners raises your risk of getting lice.