Head Lice Fact Sheet

posted Sep 19, 2017, 10:55 AM by St. Philip School

Head Lice Fact Sheet


Head lice are small insects that live on the scalp, cause itching and spread by head to head contact. They do not spread disease and anyone can get them. They are more common in children as their heads often touch when they play together. They may also be spread through objects like scarves, brushes, head phones, hats and helmets. A full course of treatment and avoiding close head-to-head activities are recommended. There is no medical reason for excluding a child with nits or live lice from school or child care.


What to look for:

Head lice:

·         Tiny wingless insects

·         Crawl and do not jump or fly

·         Size of a sesame seed and can be difficult to see

·         Greyish-brown in colour

Nits (eggs of the louse):

·         Nits attach to the hair shaft very close to the scalp

·         Size of a grain of sand

·         Brown in colour when alive, white when dead or hatched

·         Do not come off easily. Hatch in about seven days.

·         Nits more than 1 cm from the scalp are dead or hatched, or may be dandruff.


Where to look:

Lice or nits are found close to the scalp, particularly around the ears, at the back of the neck and forehead. Use a bright light and magnifying glass if available. Part and comb wet hair into small sections to help you see lice and nits better. If you only find nits, look closer for live lice. If lice and nits are present, act quickly and treat both.


How to get rid of head lice


Head lice treatment


Start lice treatment if live lice are found or if nits are less than 1cm from the scalp. Your pharmacist can help you choose a head lice product. You do not need a prescription. Read the list of ingredients and use only as directed. Most products require two treatments. The first will kill the head lice but not all nits. The second treatment, given 7 to 10 days after the first, will kill the nits that have hatched. Do not use conditioner or a 2-in-1 shampoo after treatment. Daily nit removal between treatments and hair combing are essential to get rid of head lice successfully. If you see live lice 48 hrs after the second treatment, contact your physician.


Nit treatment


Daily nit removal and hair combing are keys to getting rid of head lice. After head lice are treated, removing the nits can help to prevent a new infestation. Even with careful nit picking some live nits can be missed. Children may return to school or child care facility even if nits still remain in their hair. To remove nits, use a bright light and part hair into small sections. With a fine-toothed nit comb or your fingernails pull the nits from the hair strands starting at the roots down to the tips. This is easier when hair is wet. Wipe the nits onto a tissue and place in a bag for disposal. After treatments, wash your hands with soap and water and soak the comb in hot water.

Alternative head lice treatment

Household products such as mineral oil and vinegar, petroleum jelly, mayonnaise and hair gel have been used to treat head lice. These methods have not been proven to work. Applying these products is thought to plug the holes through which the lice breathe. These products may be even less effective if only nits are present. If used, leave the product on the head overnight. After these treatments, wash and rinse hair with regular shampoo several times. As per the Canadian Paediatric Society, using flammable, toxic and dangerous substance like gasoline or kerosene to treat head lice or using products intended for treating lice in animals are not recommended under any circumstances.


Check all close contacts.

If one person in the family has head lice, it is possible that other family members will also have them. Tell your child’s school, day-care, and children’s groups (i.e. sports, clubs, etc.) so other parents can check their children’s hair. An untreated source among close contacts is a common reason for getting head lice again.

It is important that all individuals who have head lice be treated at the same time.


Cleaning personal items

Head lice do not survive more than 3 days away from the warmth and humidity of the scalp. Nits will hatch in 7 to 10 days. Wash combs, brushes and hair accessories with hot, soapy water until all lice or nits are removed.  Then soak them in very hot water for 10 minutes.  Wash clothing, bed linens and towels in hot soapy water then put them in a hot dryer for 15 minutes.  Items that you cannot wash such as blankets, coats and stuffed animals, can be put in a plastic bag for 14 days. Avoid sharing hair brushes while undergoing treatments. Extra housecleaning is not needed. Do not use insecticide sprays.


Consult your doctor about treatment if:

       you are allergic to any of the ingredients

       you are pregnant or breastfeeding

       treating children under two years of age

       treating someone with a seizure disorder

       treating lice on eyebrows, eyelashes or beard

       the skin of the scalp is broken or infected

       the head lice infestation persists after the first two treatments


How to prevent the spread of head lice

       Check your child’s head daily during lice outbreaks when advised by your school or child care facility.

       Teach your child not to share personal items that are used on their head such as brushes, combs, barrettes, headbands, elastics, towels, hats, helmets, toques, and scarves.    


More information: parentinginottawa.com or http://www.caringforkids.cps.ca/handouts/head_lice


If you have further questions about head lice, call Ottawa Public Health at

613-580-6744 and speak with a Public Health Nurse.