Presented by: LEE KIAN CHOY

IntroductionIt’s an ectoparasites that feeds on blood and sensitive

toward the light

Mostly occurs in school-aged (5-11 y.o) children (girls more prevalent than boys)

Infection are commonly characterized by pruritis caused by feaces antigen or lice’s saliva (weeks to develop)

Chronic scratching can lead to excoriation can lead to secondary bacterial infection

Nits are normally found in behind ears and neck

Life-Cycle of Head Lice:Able to live up to one month on human heads but can

only survive for up to 2 days away from humanAn adult female can produce an average of 56 eggs

once fertilizedEggs will hatched in 7-10 days of incubation (1cm

from scalp)Hatchlings will molts 3 times (9-12 days) to become

an adult

Mode of Transmission:Mostly by close contact as head lice are unable to

jump or fly, hence, they clawed/trapeze their way to others hair

Example of transmission route:a)Making social contacts (parent-child interaction)b)Shared combs, brushes, towels, clothing, beds and

closets

Note: Head to head contact is by far the most common route of transmission

Insecticide Treatment: Permethrin: causes electrochemical abnormalities across the

membranes of excitable cells, leading to sensory hyperexcitability, incoordination and collapse

Caution: hypersensitivity towards permethrin (chrysanthemums): if there is wound on the head: child < 2 y.o (safety has not been demostrated)

pregnancy (category B)

Direction to use: Wash the hair with normal shampoo rinse and towel dry until the hair is still slightly damp. Apply permethrin to the hair and scalp (avoid contact with eyes). Leave for ten minutes, then wash out thoroughly with water and towel dry. Use a fine toothed plastic comb to remove nits. One application is usually sufficient to kill those lice. To ensure complete eradication examine the scalp after seven to ten days and reapply to clear hatchlings

Insecticide Treatment:Pyrethrin: disrupt nerve impulse transmission in lice

resulting in paralysis and death (additional of piperonyl butoxide ONLY potentiate pyrethrin activity)

Caution: hypersensitivity towards permethrin (chrysanthemums): if there is wound on the head: child < 2 y.o (safety has not been demostrated)

pregnancy (category B)

Direction to use: Wash the hair with normal shampoo rinse and towel dry until the hair is still slightly damp. Apply pyrethrin to the hair and scalp (avoid contact with eyes). Leave for ten minutes, then wash out thoroughly with water and towel dry. Use a fine toothed plastic comb to remove nits. One application is usually sufficient to kill those lice. To ensure complete eradication examine the scalp after seven to ten days and reapply if necessary.

Insecticide Treatment:Malathion (lotion): Irreversible cholinesterase

inhibitor which is vital for nerve impulse transmission

Caution: contain flammable alcohol (avoid heat): not recommended for kids < 2 y.o: hypersensitivity towards insecticides

pregnancy (category C)

Direction to use: Apply lotion to dry hair & wash hair after 8-12 hours. Use fine-tooth comb to remove dead lice, repeat the procedure after 7 days

Insecticide Treatment:Benzyl alcohol 5% lotion: act by closing their

respiratory spiracles results in asphyxiation

Caution: if there is wound on the head: child less than 6 months old: hypersensitivity towards insecticides

pregnancy (category B)

Direction to use: Apply lotion to dry hair, using enough to completely saturate scalp and hair (avoid contact with eyes); rinse off with water after 10 min; repeat treatment in 1 wk

Insecticide Treatment:Gamma Benzene Hexachloride 0.1%: stimulates

nervous system of parasite, causing seizures and death

Caution: if there is wound on the head: not safe to be used in children: history of seizures

pregnancy (category C)

Direction to use: Apply to dry hair and surrounding areas (avoid contact with mouth or eyes); allow to set for 4 min, then lather for 4 min and rinse; repeat after 7 days when necessary

Manual Treatment:10 Day Hair Conditioner Treatmenta)Apply plenty of conditioner until saturated and comb

with normal hair comb to remove tangleb)Section the hair to four direction (forward, backward,

left & right) with fine-tooth nit comb (one section at a time)

c)Wipe the comb with tissue paper and look out for lice or nits (rinse hair after combing)

d)Repeats steps above every other day for 10 dayse)Check reinfestation once a week for four weeks after

the 10 days treatment

Practice Points:The following individual should NOT use insecticide

head lice treatment:a)Baby under 2 years of ageb)Patient with insecticide allergiesc)Scalp hypersensitivityd)Pregnant/breast feeding women

All insecticides does NOT 100% eradicate head lice eggs

Wet combing with vinegar can help in removing eggs that are attached to the hair

Note: Home remedy such as vaseline, mayonnaise & suffocation-based pediculicide lotion has been advocated but insufficient scientific research has been done

Self-Management:Check among family members to ensure others are not

affected & treat concurrently if affected

Comb and hair comb/brush should be treated concurrently with pediculicides or soak in hot water

Bedding should be laundered in hot water and dry clean

Isolate school-aged children from attending school until they are properly treated

Avoid over treating the head lice which can cause resistance

Note: Disinfecting the furniture is NOT necessary

Self-Management:Prevention:To avoid re-infection of head lice make sure affected

family members are treated

Comb the hair with hair gel or tie long hair together

Remind child of school age to avoid head to head contact

Shaving the hair can be considered as the most direct way of eradicating head lice (cosmetic unacceptable)

Thank You

Reference:http://www.public.health.wa.gov.au/cproot/473/2/Head%20Lice%20Fact%20Sheet.pdf

http://emedicine.medscape.com/article/785248-overview

http://pediatrics.about.com/cs/conditions/a/head_lice.htm

Australian Medicines Handbook (2007)