Head lice: how to treat them and stop the spread

February 20, 2013, 1:41 pmYahoo!7

What are head lice, how do they spread and, most importantly, how do you treat head lice and stop the infestation. Here’s everything you need to know.

Head lice: how to treat them and stop the spread
Toddler + Preschooler
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What are head lice?


Head lice are parasites that live on the hair and scalp and need human blood to survive. Head lice, or climbers, are the actual insects. They’re red-brown in colour and about the size of a sesame seed. They make a characteristic ‘pop’ when you squeeze them between your thumb nails. Nits are head-lice eggs. They attach firmly to the hair shaft

and hatch into nymphs about seven days after the egg is laid.

How do they spread?


Head lice are wingless, so they can’t fly or jump. They have six legs with a claw at the end of each, which they use to grab onto passing hair strands to hitch a ride. Head lice are spread by head-to-head contact. Contary to popular belief, lice can’t be passed on by sharing hats and hairbrushes.

How do I spot an infestation?


Head lice expert Professor Rick Speare says finding nits in your child’s hair doesn’t necessarily mean she has head lice. “A nit can be an egg with an embryo that is going to hatch or an already hatched egg,” he explains. “Nits are difficult to remove from the hair shaft and grow out with the hair, so the eggs may still be there from when your child was

previously infected.”

An active infestation is happening if you find live lice and the only reliable way to find them is to look. “Scratching isn’t reliable because only 25 per cent of head lice are itchy,” says Professor Speare. “Poking around in the hair isn’t effective either as lice tend to run from disturbances.” The best technique is to use hair conditioner and a nit comb (see the box on the right). This stuns the lice and they stop running. When done thoroughly, up to 95 per cent of lice will also be removed with this method, so it’s a great way to start treatment.

I’ve found them! Now what?


If you find head lice, your little one’s hair should be treated. There are all manner of treatments on the market, and which type you choose comes down to personal preference and a bit of trial-and-error. Research has found, though, that silicone-based compounds called dimethicones and cyclomethicones are changing the treatment of head lice.

“These are the most effective group of head-lice treatments because they kill lice and embryos in the eggs in one treatment,” says Professor Speare. “They seem to physically interfere with the lice’s process of water loss.”

Other bug-busting treatments include:

Insecticidal products: These can be shampoos, sprays or gels that contain chemicals such as pyrethrin, permethrin, bioallethrin and malathion. If you use an insecticide, the best approach is usually two treatments, seven days apart (but always be sure to follow the instructions on the packaging). Many insecticide products don’t penetrate the eggs, so the first treatment will kill the live head lice and the second will kill the ones that hatch after the first treatment.

Herbal remedies: These treatments are popular, particularly with parents wanting to avoid chemicals. But unlike insecticide products most haven’t been clinically tested, so the evidence supporting them remains anecdotal.

Nit combs: The narrow space between the teeth of these combs drag lice out of the hair, but they’re not very effective when removing eggs unless the teeth have been specially crafted. Using the conditioner and comb method daily for at least seven days, though, is an effective approach.

Zapping combs: The comb teeth are electrically charged, so when a louse gets caught between the teeth it gets electrocuted. Some people do risky things to get rid of head lice, “but under no circumstances should you be using pet or tick treatments, bug spray, insecticidal surface sprays or kerosene,” says Professor Speare.

How do I know they’re gone?


How well your treatment has worked comes down to your choice of product, how you’ve used it and insecticidal resistance in the lice. After the treatment, comb your child’s hair with a nit comb and wipe the combings onto white paper towels to look for signs of life.

If the treatment has been effective the lice won’t move anything, including their legs or antennae. If they can move, the treatment hasn’t been successful and if some are dead

and some are still alive, they may be partly resistant to the product and you’ll need to try a different treatment. “High percentages of head lice in Australia are resistant to products with pyrethrin and permethrin, and less to malathion,” Professor Speare says. “Resistance against dimethicones is unlikely as they work differently to insecticide products.”

Did you know...
  • A recent survey found 75 per cent of kids have head lice at least once in a 12-month period.
  • Head lice become more of a problem when your child starts school.
  • Head lice don’t discriminate. They like clean and dirty hair.
  • Head lice can't survive for too long off the head so there’s no need to clean everything in sight if someone in your family has them.
  • They can’t be caught from dogs or cats: they only survive on human blood.

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