It's Head Lice Season: Experts Offer Primer On Wiping Out The Head Invaders

Head-lice incidence peaks shortly after school starts, particularly among younger children.

“These tiny head invaders are most often found in preschoolers and elementary-school students because children that age tend to play together and have close head-to-head contact in closed spaces, which makes transmission easier,” says Bernard Cohen, M. D., a pediatric dermatologist at the Children’s Center.

Here’s how to deal with them:

First and foremost, make sure your child has lice, not another condition that causes an itchy scalp and mimics lice, Cohen says. Such conditions include contact dermatitis, an inflammation of the scalp caused by an allergic reaction to certain chemicals in hair products such as gels, shampoos or conditioners. Also keep in mind that conditions such as psoriasis and seborrheic dermatitis can cause grayish skin flakes on the head that can look like nits. Key difference: Nits latch onto the base of the hair and won’t come off easily.

If your child does have lice, try an over-the-counter insecticidal (anti-lice) shampoo, but make sure you follow the instructions closely. If this doesn’t work, your doctor can prescribe stronger products. Don’t use insecticidal products repeatedly because they contain strong chemicals and can irritate and inflame the scalp. Also, using them too often may lead to resistance in head lice, making them immune to the products. Don’t bother nit-picking the scalp after treating with insecticidal shampoo.

“As long as the nits and lice are dead, there’s no reason to remove the dead bodies one by one,” Cohen says.

Forget old wives’ tales of smothering lice with mayonnaise, olive oil and Vaseline. “There’s simply no data to show that any of these works,” Cohen says.

Should you check your child’s head regularly? Not unless the child is scratching and reports an itchy scalp. In case of infestation, it is more important to treat the child’s family members because they are at higher risk for getting lice, not so much the child’s classmates, Cohen says.

Lice don’t fly, hop or jump and are only spread through direct contact with an infected person or by using an infected person’s hat, bedding or hair brushes, where nits and lice can survive for up to two days. Head lice only live on human heads. Deprived of regular blood meals, they typically die within 36 hours.

Despite the persistent social stigma associated with head lice, they have nothing to do with poor hygiene and seem to prefer healthy, clean heads, Cohen adds.

Head lice cause between 12 million and 25 million infestations each year, mostly in children under 12 years.