Head Lice Information
As we head back to school, we have to be on the look out once again for
Head Lice. Head lice affecting the scalp (Pediculosis capitis) is a very
common problem, especially in school children. There are various treatments,
but whatever approach is used they can be a persistent or recurring nuisance.
Causes
The cause is a tiny insect which lives on the scalp. It feeds by sucking
blood through the skin. The head louse grips on to the hair with its six
tiny claws.
The female lays its eggs (nits) in sacs which are glued to a hair. These
take seven to ten days to hatch. The lice then take seven to fourteen days
to become mature and ready to reproduce. The total numbers of lice thus rise
very quickly.
Head lice do not jump, fly, or swim. They spread by direct contact, "walking"
from one hair or head to another. They happen in the best circles, and do
not mean that you or your child are unclean or dirty, in fact some people
say that head lice prefer clean heads.
Head Lice only affects humans, and cannot be passed on to, or caught from
animals.
Symptoms
The main symptom, if noticed by the individual, is an itchy scalp. This
is sometimes especially so behind the ears.
Diagnosis
Approximately half of the children affected will notice itching of their
scalps which draws attention to the problem. The lice themselves are small,
about the length of a match head, and may be difficult to see, as their colour
is often close to the hair colour.
Newly laid eggs are usually close to the scalp (about 1.5cm or about 0.5in)
and as the hair grows this, and subsequently the empty sac, once it is hatched,
will move further from the scalp.
When the egg is still in the sac it is small and rather dull in colour,
and difficult to see. Once the egg has hatched, (7-10 days) the sac is white,
and easier to see.
The best way to check on the presence of lice, if you are not sure, is
to use the following lice detection regime:
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Wash the hair as normal.
-
Apply conditioner liberally, including the full length of long hair.
-
Lay out white tissues over which you will comb the hair.
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Comb the hair through with a normal comb first, to get rid of any knots.
-
With a fine tooth comb ("nit comb"), starting from the roots of the hairs,
comb out along the complete length of the hair. After each stroke check the
comb for lice and wipe it clean. Work systematically around the whole head
of hair.
-
Rinse the hair as normal.
Treatment
Firstly, don't panic! Most times you can make the diagnosis and start
the treatment yourself. If in doubt, or if the lice seem resistant to treatment,
consult the pharmacist or doctor.
There are various treatments available. The chemical treatments fall into
a number of groups:
-
Pyrethrins.
-
Synthetic pyrethroids (permethrin and phenothrin).
-
Organophosphates (malathion).
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Carbamates (carbaryl).
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Herbal.
Of these, the one which best stands up to scientific scrutiny is permethrin
1% creme rinse, but the lice can become resistant to any of the treatments,
and if a correctly applied treatment does not work, it is wise to use an
alternative on the subsequent occasion. You should not use a different
formulation of the same chemical.
Usually, you will be advised to treat once, and repeat seven days later.
Each time you wash your hair it is important to make sure the application
covers ALL the hair, and it is worth combing through the hair with a fine
tooth comb, over tissue paper, after 20 minutes.
By this time the lice should be coming out dead (not moving) and this
helps to confirm the effectiveness of the treatment. If live, mobile lice
are found at this stage, they are resistant to that treatment, and an alternative
is likely to do better.
The treatment does not kill the eggs, and the second treatment is because
any remaining eggs should have hatched, and the young lice should now be
killed. If lice are found after the second treatment it is wise either to
repeat the treatment after another week, or at least to check the hair again,as
above, using conditioner.
Treatments all have the potential for unwanted side effects, and you should
discuss the pros and cons with the pharmacist, or doctor. In addition to
unwanted side effects there is an increasing problem with lice which are
resistant to the effects of the treatments.
Only those with live lice or viable eggs should be treated. Each person
(adults as well as children) within the home should be inspected to determine
if live lice are present. All those found to be infested should be treated
simultaneously.
Cleaning the Environment
While lice don't infest the environment, they can survive off the scalp
for up to 2 days. Nits can survive even longer -- about 10 days! As a result,
it is important to give attention to items and surfaces in the environment.
Vacuum floors, furniture, cars, backpacks, etc. Do not leave the vacuum
bag in the vacuum cleaner. Seal and discard the vacuum bag.
Disinfect combs and brushes by soaking for 15 minutes in very hot water.
(Boil the water, turn off, then put in the combs and brushes.)
Machine wash clothing, hair ties, towels and bed linens in HOT water cycle
(130 degrees or more). Dry items in a HOT dryer for 20-40 minutes.
Store non-washable personal items in sealed plastic bags for 2 weeks,
dry clean, or vacuum such items thoroughly.
It is not advisable to use pesticide sprays, even the sprays that say
they are for use in the home and car. Such sprays are ineffective, poisonous,
and may contribute to the development of resistant strains of head lice.
Prevention
It is probably worth checking your child for lice weekly, and undertaking
treatment if any are found. Teaching your children not to share combs, brushes,
sports gear, sweaters, hair ties, hats, baseball caps, hair accessories,
etc. is also a good idea.
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