- Head lice are small insects with six legs. They are often said to be "as large as a match head"; in fact, they are often not much bigger than a pin head, and rarely bigger than a sesame seed (the seeds on burger buns).
- They live on, or very close to the scalp, and don’t wander far down the hair shafts for very long.
- The louse’s mouth is like a very small needle. It sticks this into the scalp and drinks the blood.
- They can only live on human beings; you can’t catch them from animals.
- Nits are not the same thing as lice. Lice are the insects which move around the head. Nits are egg cases laid by lice, stuck on to hair shafts; they are smaller than a pin head and are pearly white.
- If you have nits it doesn’t always mean that you have head lice. When you have got rid of all the lice, the nits will stay stuck to the hair until it grows out.
- You only have head lice if you can find a living, moving louse (not a nit) on the scalp.
- Anybody can get head lice but they are much rarer in adults.
- Head louse infection is a problem of the whole community, not just the schools.
- Infection is common during school holidays as well as during term time. Parents start to worry more about lice when children go back to school because they think the lice are being caught there.
- A lot of infections are caught from close family and friends in the home and community, not from the school.
- It’s not just children who have them; adults get them too.
- It’s often said that head lice prefer clean, short hair. In fact, they probably don’t much care whether hair is dirty or clean, short or long. Short hair may make it easier for them to get from one head to another.
- Head lice can walk from one head to another when the heads are touching for some time.
- You are very unlikely to pick up head lice from brief contact with other people. The longer you have head to head contact with someone who has lice, the more likely it is you will get them too.
- They can’t swim, fly, hop or jump. The idea that they can jump may have come from the fact that, when dry hair is combed, a head louse caught on the teeth of the comb is sometimes flicked off by static electricity (this is one reason why detection combing should be done with the hair damp).
- You don’t get them from objects such as the chair back. Although it’s just possible that a louse might get from one head to another if a hat is shared, this is very unlikely. It’s not the way infection is usually caught.
- If you catch one or two lice, they may breed and increase slowly in number. At this stage, most people don’t have any symptoms and won’t know they have lice unless they look very carefully for them.
- For the first two or three months, there is usually no itch, but then the scalp may start to itch badly. This is due to an allergy, not to the louse bites themselves.
- Most people only realise they have head lice when this itch starts. By then they’ve had lice on their head for two or three months without knowing it.
- In most infections, there aren’t more than a dozen or so lice on the scalp at any one time.
- Some people never get the itch, including adults. They may have a few lice on their heads for years without knowing it, and can pass them to other people.
- Louse droppings may fall on to the pillow during the night. Pillows may then get dirty more quickly than usual.
- Combing is an important part of good personal care, but head lice are not easily damaged by it. Good hair care may help to spot lice early and so help to control them. There is no evidence that the old slogans "Break its legs, so it can’t lay eggs" or "A legless louse is an eggless louse" have any truth in them.
- The best way to stop infection is for families to learn how to check their own heads. This way they can find any lice before they have a chance to breed. They can then treat them and stop them going round the family.
- The way to check heads is called "detection combing". It can be done as often as families want to. The way to do it is in the sheet "Have you got head lice? Detection combing - how to do it."
- If a living, moving louse is found on one of the family’s heads, the others should be checked carefully. Then any of them who have living lice should be treated at the same time.
- You should only ever treat someone for head lice if you have found a living, moving louse.
- The best treatment is to use lotion (NOT shampoo) from the chemist or your local doctor’s surgery.
- The way to use the lotion is given in "Head lice: how to treat them - notes for families"
- If you are sure you have found living lice after proper treatment, don’t keep putting more lotion on; ask advice from the local chemist, the health visitor, your family doctor, or the school nurse.
- The problem may not be head lice at all. Often we think there are lice when there aren’t really any there. We all start to itch as soon as head lice are mentioned.
- There are other causes for itching of the scalp. Using head louse lotion can make these worse.
- Using lotion over and over again can cause dermatitis, which itself makes the head itch.
- When living, moving lice are found, they can almost always be cleared by using the right lotion. This will only work if enough of it is used, if it is put on in the right way, and if any other family members who have lice are treated properly at the same time.
- A day or two after using the lotion, you sometimes find little lice still there. These have hatched out of the eggs since you put the lotion on, and will be killed if you put the lotion on again after seven days.
- When you have got rid of the lice, you might still itch for two or three weeks. This doesn’t mean you still have lice. Check the head carefully. Remember, you don’t have head lice if you can’t find a moving living louse.
- When you have got rid of all the lice, the nits (empty egg cases stuck on the hairs) will still be there. This doesn’t mean you still have lice, and you shouldn’t treat again no matter how many nits there are if you can’t find a living louse.
- People who think their children keep on getting head lice may have made the mistakes listed above, and may keep on "treating" lice which have long since been cleared, or were never even there in the first place.
- If children do really keep on having living lice, this is most likely to be due to not doing the treatment properly and not treating all those close contacts who have also been found to have lice. Remember, if infection really does keep on happening, it is almost always from a member of the family, or a close friend. It is rarely from other children in the classroom except from a "best friend".
- If you still have problems, ask your family doctor, health visitor, local chemist, or health visitor if a wet-combing method to remove the head lice might help.
- Schools must remember that most lice are caught in the family and the local community, not in the classroom.
- "Nitty Norah" head checks will not help, but the School Nurse can advise and support parents to check their own families.
- "Alert" letters should not be sent out. These can cause an "outbreak" of imaginary lice.
- Children who may have lice should not be excluded from school; if they do have lice, they will probably have been there for weeks already. The School Nurse can help the parents to make sure whether there really are lice there, and how to get rid of them if they are.
- The school should give information on lice for parents and staff including regular detection combing and how to do it. This should be on a regular basis, not just when there is thought to be an "outbreak", and should be done with the School Nurses.
- Talks for parents by the School Nurse can be helpful.
- Make sure that all family members know about good hair care, including regular, thorough combing.
- The only way to control head lice which works is for the family to check their own heads.
- Check all the family’s heads every now and then with a special plastic detection comb from the chemist’s shop. Read "Detection combing - how to do it".
- All the family means everyone (adults as well as children) in the same household.
- Only if you are sure you have found living, moving head lice in your family, tell your relatives and close friends so that they can check their own heads. Treat any of your family you are sure have lice at the same time. Ask the at the chemist’s, the surgery, or the School Nurse which lotion you should use.
- Remember, never use the lotions unless you are sure you have found living, moving head lice (not nits).
- Try not to worry too much about head lice. They are unpleasant, but they rarely do any harm other than causing an itchy scalp.
(This document was originally appendix 7 of Head Lice: a report for Consultants in Communicable Disease Control (CCDCs).)
It is one of three appendices written for families:
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