Health Tips

Head lice eggs (nits) are brown or white (empty shells) and attached to the hair.

If you have been infected by head lice (singular form: head louse) as a child before, you know that it is not a pleasant experience. Not only you had this constant urge to scratch your scalp, you were also bothered by the social stigma surrounding the condition. Fellow humans, why do we always have to be so unkind to each other?

Anyway. Head lice can affect anyone, but infestation is more common in the following groups:

• children between the ages of 4 and 11 years (the peak is 7-8 years)

• girls than boys

• the start of the school year

• children with long hair.

Reason? Unknown. 

How does head lice come about?

The head louse, or Pediculus humanus capitis, is a parasitic insect that can be found on the head, eyebrows, and eyelashes of people. Ready for a cute portrait shot of an adult head louse? Don't say we didn't warn you –

Male human head louse, Pediculus humanus capitis. By Gilles San Martin - originally posted to Flickr as Male human head louse, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=11208622

But head lice do not look like this all the time. In fact, head lice have three forms:

1. Egg/Nit

2. 

Source: ©DermNet New Zealand via Creative Commons Attribution-NonCommercial-NoDerivs 3.0 (New Zealand)

Nits are lice eggs laid by the adult female head louse at the base of the hair shaft nearest the scalp. They are very small and hard to detect, and we are not exaggerating when we say they.are.sticky. Head lice nits usually take about 8–9 days to hatch.

2. Nymph

Meet the teenager of head lice, nymph. They are the immature louse that hatches from the nit. A nymph looks like an adult head louse, but is smaller.

3. Adult

Source: ©DermNet New Zealand via Creative Commons Attribution-NonCommercial-NoDerivs 3.0 (New Zealand)

Just like what you’ve seen in the image above, the fully grown and developed adult louse is about the size of a sesame seed, has six legs, and is tan to grayish-white in color. Adult head lice may look darker in persons with dark hair than in persons with light hair. Adult female head lice are usually larger than males and can lay about six eggs each day (omg!)

Actual size of the three lice forms compared to a penny. Credit: CDC Photo

Most people with head lice do not have any symptoms. Some people feel itching or skin irritation of the scalp, neck, and ears. This is caused by a reaction to lice saliva, which the lice inject into the skin during feeding. Because, well, the head lice actually feed on human’s blood to survive. Certainly did not expect real-life dracula to look like an insect. 

Head-to-head contact with an already infested person is the most common way to get head lice. Such contact can take place during play at school, at home, and elsewhere (sports activities, playground, sleepover parties, camp).

Myths Busted: Head Lice Edition

The thing is, not many people know the facts about head lice. There are many misconceptions about this condition, and we are here to bust them all.

Myth 1: Head lice can hop, jump, or fly.

The truth is that head lice can only travel by crawling. Head lice crawl around the scalp, staying as close as 1 cm in order to feed and gain warmth. It would be really scary if it can fly. 

Myth 2: Head lice can be easily acquired from sharing personal belongings such as hats, clothing, and hair brushes.

Although this is not impossible, it is very unlikely. Head lice are most commonly spread by head-to head contact in environments where children congregate such as schools and daycares. Congregation does not seem possible in the near future anyway, ‘thanks’ to the Covid-19 pandemic.

Myth 3: Head lice are a result of uncleanliness.

This is perhaps the source of all the social stigmas associated with head lice. Some people even think that head lice only affect those with a lower socioeconomic status or people with poor hygiene. The truth is all socioeconomic classes are affected regardless of the degree of cleanliness as hygiene does not play a role.

Myth 4: Head lice can live everywhere.

An adult head louse can live about 30 days on a person’s head but will die within one or two days if it falls off a person. So as tough as these little guys seem, they are pretty selective in where they live and cannot live everywhere other than the scalp. 

Myth 5: Head lice spread diseases.

Although a secondary skin infection can occur due to excessive scratching that resulted from the head lice, the lice themselves do not cause any infections or diseases. So no, don’t treat head lice like a plague.

Your children may feel upset when they find out about head lice. Keep reassuring them that it is not a big deal and there are effective treatments that can get rid of it.

How to detect head lice?

Not sure if what you or your child has are indeed head lice? Here are the steps you can take to examine the scalp. 

1. Prepare a fine-toothed comb. Alternatively, you can also buy a special nit combs from any nearby pharmacy to assist with the diagnosis.

2. Before using the fine-toothed/special combs, use a regular brush or comb to remove tangles. This can be done while the hair is wet or dry. If the hair is wet, apply hair conditioner to make the hair easier to comb.

3. Place the fine-toothed/special comb at the top of the head, touching the scalp. Pull the comb through the hair from roots to ends. After each stroke, carefully examine the comb for lice or eggs.

4. Comb the entire head at least twice.

Note: Finding eggs (nits) without lice does not necessarily mean that there is an active infestation; nits can be found for months after lice are treated. Because lice lay eggs at the base of the hair shaft, the identification of nits within ¼ inch of the scalp suggests (but does not confirm) an active infestation.

If you are unsure whether your child has lice, make an appointment for your child to be examined before you start treatment. A doctor can examine the head under a special lamp, which causes nits to glow a pale blue color.

Treatment for Head Lice

There are several options for getting rid of head lice, including creams and liquids, combing, and oral medicine (pills). It is important to follow directions carefully to be sure that the treatment works.

If you are sure that your child (over age two years) has head lice, you can use over-the-counter lice treatments. If your child is under age two years, contact the child’s doctor for treatment advice.

Topical Insecticide

This isn’t your typical insecticide that is used in agriculture. A topical insecticide is a substance, usually a lotion or gel, that is applied to the scalp to kill lice. The most commonly used insecticide for head lice is permethrin (A-Lices) and dimeticone (Lice Clear, Nitclear), both of which are over-the-counter products you can find at any nearby pharmacy. Other insecticides also include malathion, benzyl alcohol, spinosad and ivermectin, some of which require a doctor’s prescription.

When using these products, do take note of the following:

• Many of these products are not suitable for young children. Consult a healthcare professional to find out more.

• You should also avoid use of hair conditioner or shampoo-conditioner combination products before application of the insecticide.

• Duration required to leave the product on the scalp: Formulations require between five minutes and eight hours before combing or washing out. Follow the manufacturer's instructions for applying the insecticide carefully.

• Many products should be applied to dry hair.

• Specific instructions on how to use the products. E.g. frequency of usage, duration of treatment

• Only use one insecticide at a time.

• Manage your expectation: A few live lice may be seen 8 to 12 hours after using an insecticide, and there is no need to immediately reapply the insecticide if they are moving slower than they were prior to treatment. However, if lice are as active as before treatment, the treatment may not be effective. 

A healthcare professional can provide guidance regarding the selection of an appropriate treatment.

Wet Combing

Does not fancy an insecticide? Your child is too young for topical insecticide? Consider wet combing.

Thanks for the polite permission of the Community Hygiene Concern, Joanna Ibarra, CC BY-SA 3.0 , via Wikimedia Commons

Wet-combing is a way to remove lice from the hair with careful and repeated combing. However, wet-combing is time consuming and must be repeated multiple times over a period of a few weeks. Here is how you do it:

1. Wet the hair and add a lubricant, such as hair conditioner or cream rinse, vinegar, or olive oil. 

2. Use a fine-toothed comb to comb through the hair, just like how we described above. A lice comb may be provided in the lice medication package, or a flea comb can be used. 

3. The combing session should take 15 to 30 minutes, depending on the length and thickness of the hair. Comb every three to four days for two weeks after you find any large, adult lice.

Wet-combing can help suffocating the head lice with the lubricant used. 

Preventing Head Lice Spread

Adults and children who live with a person diagnosed with lice should be examined for lice and treated if needed. Anyone who sleeps in the same bed should be treated for lice, even if no lice or eggs are found.

To thoroughly clean the environment,

• Clothing, bedding, and towels used within 48 hours before treatment should be washed in hot water and dried in an electric dryer on the hot setting. Dry cleaning is also effective. 

• You can use a vacuum to clean furniture, carpet, and car seats. 

• Items that cannot be washed or vacuumed can be sealed inside a plastic bag for two weeks. Items that the person used more than two days before treatment are not likely to be infested because head lice cannot survive off the body for more than 48 hours. 

• You do not need to have your home or belongings sprayed with insecticide. This is important! Using insecticide without professional help can cause toxicity and harm your health, okay?

A note from Doc2Us

If you have any questions related to head lice, you can consult our professional doctors and healthcare professionals on Doc2Us. Doc2Us is a mobile application that allows you to talk to a doctor or any healthcare professionals via text chat at any time and from anywhere. 

Download Doc2Us app on Apple App Store, Google Play Store and Huawei App Gallery; or use our web chat at https://web.doc2us.com/

Till then, stay safe and take care!

References

1. UpToDate - Patient Education: Head Lice (Beyond the Basics)

2. Pharmacy Times - Managing Head Lice

3. C+D - How to recognise and treat headlice

4. CDC - Head Lice FAQs

Written by

Ms Joyce Toh