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Lice 101: The BugDoc is in

When a student comes home with that dreaded school note about lice, the effect is a little like the announcement of an epidemic: The family is quarantined and vigorously treated until the contaminated persons have been declared safe.

It’s a lot of fuss about a little insect that really doesn’t do much except live on our heads.

Most people know at least two things about lice: They live in hair, and you do not want them. At all. 

David Shetlar, professor emeritus of urban landscape entomology at Ohio State, knows a good deal more than that about the little pests. (He’s even known as the BugDoc.) He shares his insights here in time for back-to-school season.

How common are lice?

“Almost every family that I talk to, it’s probably a 50-50 chance that one of their children has come home with head lice,” Shetlar said.

Lice aren’t picky about whether their humans are fond of showers or have bad hygiene. “They are perfectly well adapted to deal with the normal body oils and greases, and soapy water doesn’t seem to have much of an effect on them,” Shetlar said.

Lice don’t respect social class either. “The lice don’t care how much money that you have; all they care about is that you’re alive and you’ve got blood.”

How do they spread?

Lice can’t live long when they’re away from a human host. That means the lice that appeared in your hair have been passed from person to person in a chain all the way back to prehistoric times, and now you’re the lucky host.

“About 20 to 30 percent of humans who get lice do not have a reaction to the bites,” Shetlar said. “There’s always some people out there that have lice that don’t even know about it until maybe they go to the barber.”

Lice can’t jump or fly. The way they move around is by contact — such as if you put your head together with a friend for a selfie, or you share a hat or scarf. Family members are likely to share personal items, so that’s why lice will spread within a family.

What do they eat?

There are two types of lice: biting and sucking lice.

The biting kind live mainly on birds, and sucking lice live on humans and other mammals. Human lice pierce the skin and feed on blood and blood byproducts.

Are they dangerous, or is it mostly the “ick factor” that bothers people?

Head lice have never been implicated in transmitting disease, Shetlar said.

“People who are allergic to saliva and get highly irritated skin can scratch the skin and get secondary infections, and that occasionally occurs. It’s not all that common on the scalp.”

Body lice can transmit serious diseases such as typhus, but this kind of lice — like their fellow pests the bedbugs — took a hit after insecticides such as DDT were developed. These lice do not live in hair.

“We almost never see them anymore,” Shetlar said.

Lice don’t care how much money that you have. All they care about is that you’re alive and you’ve got blood.

David Shetlar, Ohio State Professor Emeritus
What about the rumors about “super lice”?

That’s overblown, Shetlar said. So-called super lice are simply lice that have become resistant to common over-the-counter lice treatments, most of which contain natural pyrethrin, which is weaker than synthetic versions.

“It’s not a super louse in that it moves faster and reproduces faster and is super strong.”

Shetlar estimates that because of the way people have been using these treatments, more than 50 percent of lice are probably resistant. They’re the new normal.

What’s the best way to get rid of lice?

The days of humiliating kids by sending them to school with shaved heads are over. Shetlar recommends getting prescription treatments, which are strong enough to kill resistant lice. These may contain a systemic pesticide that is absorbed into the skin.

“When it’s used correctly, that’s not going to pose any danger to the people, but it’s extremely effective against the lice,” Shetlar says.

For those who are uncomfortable with using insecticides on their children, there are now organic de-lousing services. They use a lot of essential oils and old-fashioned lousing combs to remove lice and their eggs — nits — by hand, Shetlar explained.

(Yes, that makes them professional nitpickers.)

Having children at schools keep their hats and coats in separate personal spaces can also help prevent the spread of lice.  

“The most important thing is don’t be embarrassed (by lice),” Shetlar said. “Don’t completely try to do it yourself; reach out to your physician or nurse’s assistants and get a good prescription for the right material that’ll work, rather than trying to buy stuff over the counter.”