Head Lice Fact Sheet

30 June, 2020

head lice fact sheet

Lice Prevention and recommendations

Help Control Head Lice

What Are Head Lice?
Head lice are small insects that live on the scalp. Anyone can get head lice. They are common in classrooms and day care centres because children play closely together.

Head lice are not dangerous and they do not spread disease, but they are contagious and can be a very pesky problem. Having dirty hair does not cause head lice. Head lice cannot fly or jump and you cannot get them from your pets.

While they may be found anywhere on the head, they prefer to live on the scalp along the neckline and behind the ears. When lice bite the scalp, they cause itching.

How Can I Tell If My Child Has Head Lice?

Children may say they have a tickling feeling on their head or may be very itchy on their scalp.

The only way to be sure a person has an active case of lice is to find live lice. Children can have a few nits (lice eggs) without actually having an active case of head lice. Usually children have no more than 10 to 20 live lice.

Lice are not easy to see and can be hard to find. They are about the size of a sesame seed. They are usually greyish white or brown.

Nits are small, oval and blend into the color of the hair. Each nit is firmly attached to a hair. They cannot be washed out or flicked off like dandruff. Finding nits does not mean the individual has a current infestation and they should not be treated based on finding nits.

Pictures courtesy of CDC/Dr. D D JuranekHow Do I Check for Lice?
Apply ample hair conditioner to dry hair, enough to soak from the scalp to the end of the strands.
Remove tangles with a regular comb.
Start behind the ears and comb the hair section by section. Separating the hair with hair clips is helpful.
Place the lice comb against the scalp and pull to the end of the hair.
Check the comb for lice after each pull.
Wipe the comb with a tissue each time and look for lice.
Place the tissue in a bag.
Check all the hair over the entire head.
Repeat combing for every part of the head at least 5 times.
Once finished, tie the bag with the soiled tissues and throw it in the garbage.
If lice are detected and treatment is required, make sure that all conditioner is washed from the hair prior to treatment.

What is the Treatment for Head Lice?
Overtreatment and misdiagnosis are common. Individuals with live lice in their hair should be treated. Do not treat anyone with a head lice product unless you find live lice. The presence of nits indicates a past infestation that may not be active.

Check everyone in the home for head lice.

There are a number of very effective treatments for head lice. Most contain an insecticide that kills the lice. They are pyrethrin (found in R&CTM shampoo/ conditioner) and permethrin (Nix® or Kwellada-P®).

Non-insecticidal treatments include:
isopropyl myristate/ cyclomethicone (ResultzTM) has been approved for use in Canada for individuals 4 years of age and older. It works by breaking down the waxy exoskeleton (‘skin’) of lice. The lice get dehydrated and die.
Dimeicone solution (NYDA) affects the insect’s breathing apparatus and suffocates the insect. It is not recommended for children < 2 years of age.

All of the above products require a second application 7 to 10 days after the first treatment.

Tell the pharmacist if anyone needing treatment is pregnant,
breastfeeding, under four years of age, has allergies or a serious health problem.
A pharmacist, doctor or public health nurse can help you choose the best product for you.

If live lice (not nits) are found in the hair 24 to 48 hours after a treatment with one product:
Treat right away with a different treatment product;
Repeat this treatment 7 – 10 days later.
The presence of nits indicates a past infestation that may not be currently active;
Head lice are common among young children;
Head lice do not spread disease;
Cases of head lice are often misdiagnosed;
Children can have head lice for several weeks with no symptoms.
Examine all of the household members for head lice every day for 3 weeks after the first treatment.

Do Other Treatments Work?
Many home recipes and products sold in stores are based on mixtures of essential oils (eucalyptus, lavender, tea tree, etc.), salts or other natural substances. Some people have used oils like mayonnaise, olive oil and Vaseline or hair gels to try to smother lice. There is no proof that any of these work.

How Can I Help the Treatment Be More Effective?
Each product is different and has detailed directions for use. For example one product might say it should be put on dry hair while another should be put on wet hair. Each will say how long it should be left on the hair before rinsing out.
It is very important to read and follow the package directions carefully.
Home treatments, such as vinegar rinses, should not be used as they may make the treatment less effective.
Avoid unnecessary contact with the product since it can be absorbed through the skin.
Children with head lice should be treated and can attend school or child care as usual.

‘No-nit’ policies that keep children with head lice away from school are not necessary because:How Can You Prevent the Spread of
Head Lice?
Teach your children how head lice are spread - by direct contact with the head of someone with an infestation and to avoid this kind of activity.
It is a good idea to teach your children not to share brushes, combs or head gear such as hats, bandanas, etc.
Check your child’s head for live lice once a week all year long and daily during an outbreak.
Head to head contact may be less if long hair is braided or tied back.
All personal hair care items such as combs, barrettes, etc. Repeat this daily until the lice are gone.
Items that have been in prolonged or intimate contact with the child’s head (bedding, hats, etc.) at the time of first treatment.

What Cleaning Needs to Be Done?
Lice cannot live for more than 2-3 days away from the scalp so excessive cleaning is not necessary.
Choose the best method to clean the following items (washing in hot water for 15 minutes or running through a drier on the hottest setting):

For items that cannot be washed they should be placed in a sealed plastic bag for two weeks or for 48 hours
at -10° C.

There is no need to vacuum or wash floors, carpets or furniture.

Do not use household sprays or lice sprays. They do not work and may be harmful to people.

For more information contact your local public health office, your physician, nurse practitioner OR HealthLine at 811.

References: Infectious Diseases and Immunization Committee, Canadian Pediatric Society (2016); Kids Health (2015); Harvard School of Public Health (2014); American Academy of Pediatrics (2015); Nova Scotia Public Health Services (2008)

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