(Cleveland) - Back school also means back to your kids possibly being exposed to lice.

They may sound gross, but lice are not dangerous and are actually very common among children 3 to 12 years old.

And kids who end up with them are not dirty, or avoid washing their hair, lice are simply contagious.

Dr. Emma Raizman is a pediatrician at Cleveland Clinic Children’s. She says one of the first things parents should know about lice is how it spreads.

“What really will spread lice is very close contact, so being head to head, sharing hair accessories that type of thing, but just being in a classroom with a child that has lice does not spread it,“ says Dr. Raizman.

Dr. Raizman says if your child seems to be scratching their head a lot you should check their scalp. If you spot something try to determine if it’s an active lice infection.

A mild infection would consist of 1 or 2 lice, but a severe infection could involve 100-200.

In either case, Dr. Raizman says, your child should not be held out of school for any length of time.

“If it’s a mild infection, really the school nurse should call the parents, let them know, but they should stay in school. If it’s a severe infection we may want to actually send them home, get them treated, but then they should come right back,” says Dr. Raizman.

Dr. Raizman says over-the-counter lice treatments are very effective. She says after it’s applied, a lice comb is used to comb out the “nits.” Once that’s done, start washing your child’s bedding, hats, clothing, and anything else their head may have come into contact with.

Use hot water that’s at least 130 degrees and for anything that you can’t wash you should “bag it up.”

“Anything that you can’t wash you want to just put in a trash bag and let it sit for about two weeks because that’s pretty much the life-cycle of the lice and so, if there are any eggs that will take care of it as well.”

Dr. Raizman says one treatment usually does the trick, but sometimes a second one is applied 7 to 10 days after the first.

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