Pest Resources

Where Do Lice Come From?

Head lice and nit combs have been found in the tombs of Egyptian mummies so they have been around for a long time, thousands of years in fact! 

Head lice infestations are spread through head to head contact, adult lice live on the scalp and feed on human blood up to 5 times a day!

Thankfully head lice do not spread disease or bacterial infections. They do not pose a serious risk to a human head but the itching can be irritating.

A head lice infestation affects children mostly, due to the close interaction they have with each other. However, anyone can be infected with headlice, and it is not down to poor personal hygiene, the hair of an infested person can be dirty or clean.

People should not think just because they skipped a shower that is why they have head lice.

According to the centers for disease control and prevention around 6-12 million people in the United States can be affected at any one time.

You may be thinking where do lice come from in the first place? In this article, we will answer this question and a few other frequently asked questions about this highly contagious insect.

Male human head louse

What are head lice?

Head lice (Pediculus humanus capitis) are a highly contagious blood-sucking parasite.

Head lice have six legs, that have claws on them to grip tightly to the hair shaft.

Head lice do not have wings so are unable to fly, they simply crawl along the human scalp and hair shafts.

They are very small in size about the size of a sesame seed, and difficult to spot as they move quickly and avoid light if they can. However, they are visible to the naked eye.

Lice eggs (nits) are even smaller. Empty nits eggshells are easier to see as they are a lighter color.

A head louse can be brown, white or tan in color.

The life cycle of a head louse

The life cycle of a head louse is fairly straightforward. The life cycle below will give you an idea of the stages and what to expect and when.


Eggs (nits) are head lice eggs, they are often confused with dandruff, and hair spray. The female louse lays eggs (nits) and attaches the eggs to the hair shaft, with a substance produced by the female louse, this substance makes removal very difficult.

Eggs are around 0.3 mm to 0.8mm in size, oval-shaped and white.


When a nymph hatches the shell becomes more visible and remains attached to the hair shaft.

The nymphs are the size of a pinhead and look like an adult in form only smaller. The nymphs will molt three times to get to adult size. This will take 7 days in total.

Adult head lice

The female head lice tend to be larger than the males. Both males and females live for 30 days on average.

The females lay the eggs, up to 8 nits a day can be laid.

One of the frequently asked questions is how long do head lice live without feeding on blood? If they do not have human blood they will die after 1 or 2 days.

Types of lice

The most common types of lice are head lice, body lice and pubic lice.

Head lice

Head lice cannot live without a human host. They can only survive for a couple of days away from the human head. To survive head lice need blood and warmth from human hosts.

Head lice can be found anywhere on the head, but most commonly you will find them around the ears and at the back of the neck where it is nice a warm, due to more hair being there.

Head lice will not live, feed, and breed on dogs, and cats, or other animals, so your pets are safe.

Body lice

It is thought that body lice evolved after humans started to wear clothes, the fibres being thicker than a human hair.

Body lice behave differently to head lice, the body louse will lay eggs and live on clothing rather than a person’s hair.

The body louse will crawl onto the human host to feed on blood.

Body lice can spread disease

According to the centers for disease control and prevention body lice are the only louse known to do so.

The diseases include:

  • Relapsing fever.
  • Trench fever.
  • Louse borne Typhus.

Pubic lice

Pubic lice have large front legs and this species resembles a crab because of the large front legs. Because of their appearance, they have been nicknamed crabs.

Pubic lice are the smallest species of lice and are not passed on by head to head contact but by direct contact during sexual activity.

They live in pubic hair and can be found in eyelashes and eyebrows of the host and will like head lice cause itchiness.

Symptoms of head lice

A head lice infestation can have the following symptoms:

  • Itching. Itching is the most common symptom of head lice and occurs mainly around the ears, neck and scalp.
  • Tickling. A tickling feeling as the louse moves on the scalp.
  • Live lice or dead lice. Found on the scalp, they can be difficult to spot.
  • Lice eggs (nits) on the hair shafts. Nits are stuck in place to the hair shaft, when ready they will hatch into nymphs (baby head lice). This happens after a week or so.
  • Bites and sores on the scalp. When the head lice feed on the blood from a person’s head they secrete an anticoagulant which causes an allergic reaction, which leads to itching to occur. If bacteria gets into the wound this could cause an infection.
  • Head lice can leave a person feeling irritable and anxious, due to the itchiness keeping them awake and the worry of what other people think about them with head lice.

What attracts lice to humans?

Children who live in crowded conditions may be more susceptible to head lice, close contact and sharing the same bed can easily pass on a head lice infestation.

There are two ways a lice infestation can be passed on and that is direct head to head contact, children often play closely with each other, and through sharing hats, hair accessories such as hair ties, hair brushes and other personal items.

Body lice are spread through clothing and can be prevented by frequent washing of the clothes. It is best not to share clothes.

Lice treatment

Traditional lice treatment products are available either prescription medications from the doctor, natural remedies or over the counter treatments, lice head treatments that are natural products or alternatives have no recommendations by the centers for disease control.

Also, a holistic product not regulated by the Food and Drug Administration may carry risks, particularly in small children.

If you do not want to use chemicals you could try essential oils, such as Tea tree oil, Eucalyptus oil, Neem Oil, and Lavender oil.

Wet combing

  • Ideally, try this treatment first, use with conditioner, comb through the hair to collect live head lice. Comb through the hair to remove any tangles first.
  • As this process takes time sit the child comfortably with a book or a good film!
  • Apply conditioner to the hair, this makes it difficult for an adult louse to move through the hair.
  • Comb through the hair from the scalp to the ends, after each comb wipe it on a tissue and check for lice and eggs, they are more commonly found around the ears and back of the neck.
  • Comb through sections at least 5 times before moving on to the next section.

There are three steps to follow for lice treatment no matter which type of lice

  1. Kill the adult louse.
  2. Kill and remove the eggs.
  3. Treat affected areas and clothing.

The most commonly used product is pediculicide shampoo. Follow the instructions carefully.

Any eggs that are still attached to the hair shaft of an infested person can be removed with a nit comb.

Vacuum the entire house to remove any hairs that have eggs still attached and wash bedding, towels and clothing on high heat above 130 F, and seal up in bags any children’s stuffed animals for a week to ensure the lice have died.

Comb through the hair weekly with a fine comb to remove any adult lice and eggs (nits). Even one live head louse can start off another lice infestation.

Super Lice

Some lice treatments have not been effective due to head lice building up an immunity therefore they do not kill head lice.

In some areas of the United States, you can treat head lice, which are thought to be so-called super lice with lice medications that contain Ivermectin, this type of lice treatment requires a doctors prescription due to its strength to get rid of head lice.

Prevention of head lice

To date, there is not a product available to prevent the spreading of head lice.

Precautions can be taken:

  1. Avoid close contact with others.
  2. Do not share combs and hair brushes.
  3. Tie back long hair, head lice will find it more difficult to spread.
  4. do not share hats and hair accessories.
  5. Hats and scarves should be stored in a bag at school rather than on hooks to prevent spreading head lice.
  6. After treatment disinfect combs and brushes used by someone who has had head lice, soak in hot water with a temperature of 130 F for 5-10 minutes.

And finally,

So now you know where lice come from! Lice come simply from other people.

Remember that head lice are treatable, and it does not affect only dirty hair, head lice treatments require patience, stick with it and you should be lice-free very soon.

Please take a look at the rest of our website where you will find related links and advice and tips on various different pests.

Should you have any questions please feel free to drop us an email, we do our best to respond as quickly as possible.

Good luck!

Ronald has 25 years of pest control experience under his belt. He scrutinizes each pest control method, product and process. Each pest resource we list on our website goes through an in-depth fact checking process.

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