FAQ - Lice
Q: Can lice jump, fly or swim?
No, they cannot. They do not have wings or strong enough legs for flying. They move by crawling along the hair shaft. They are often seen to "jump" but actually static from combing dry hair causes this flicking of the louse.
Q: Do they prefer dirty hair to clean hair?
No, they have no particular preference.
Q: Will a short haircut prevent a louse infestation?
No, they can live on 1cm of hair.
Q: Can they be caught by sharing hats, combs, earphones or bedding?
No, once a louse has dropped off the hair it is either injured or too weak to crawl back onto the host and will therefore die.
Q: Who is most affected by head lice?
7 to 11 year olds appear to be more likely to catch head lice, females generally show higher prevalence.
Q: Should you treat the whole family if one member is found to have head lice?
Check everyone with a plastic lice comb and only treat if a live louse is found. The use of insecticidal products on a regular basis will not prevent head lice transmission and may result in insecticidal resistance.
Q: How can the spread of head lice be minimised?
The average time a child in Britain has had head lice before detection is between 3 and 4 months, during which time she/he has been transmitting the infection to other people. Head lice are always caught from direct head to head contact with someone who has them. Spread can be minimised in the following ways:
- By encouraging families to check their hair regularly using a fine toothed plastic detection comb. This will help detect cases early.
- By careful "contact tracing" i.e. when head lice are found all the people that the subject has been in contact with over the previous months should be informed, checked, and treated if a live louse is found.
- By raising public awareness that this is a community not just a childhood or school problem.
Q: What is the advantage of lotions over shampoos?
Lotions deliver a high concentration of insecticide to lice and eggs, which can be up to 1,000 times higher than that of a shampoo. The contact time with the hair is much longer for lotions, the optimum time being 12 hours.
Q: Are the 2-hour lotions as effective as the 12-hour products?
The question of treatment time is often raised, especially by parents, some of whom dislike the idea of leaving insecticide on a child's head overnight. Laboratory evidence is that the 2-hour treatments with alcoholic lotion kills lice and eggs, but field experience indicates that the 12-hour treatments are more effective.
Q: When should there be a repeat treatment?
All head lice products need a second treatment a week later. The first treatment will not kill all of the eggs laid by the louse so some eggs will hatch. This second treatment is to ensure that any newly emerged nymphs are killed.
Q: How effective are alternative treatments?
If you would rather not use an insecticidal lotion it is possible to use a fine-toothed detection comb on damp hair. Conditioner may help the comb to move through the hair but it is not necessary, oil can also be used to ease the removal of the egg cases. Dry combing will be just as effective but electrically charged dry hair can cause the lice to be propelled off the hair due to the static charge. There is no scientific evidence that combing will work and it takes quite a long time to achieve a cure - at least half an hour per person every three days for two weeks or longer. The length of time will depend on how long the infection has gone unnoticed and how heavy it is as a result.
Some people prefer to use herbal remedies such as tea tree, lavender, neem and other essential oils but so far these have proven to be ineffective at clearing head lice infections. Only specially formulated insecticidal lotions are effective against head lice, other treatments may provide temporary relief but will not cure the problem.
