How long do lice live on a person's head?

Lice are species-specific parasites that live only on the human body and feed only on its blood. This means that they do not parasitize other species, such as dogs or cats. That is, it is impossible to catch lice from pets; they are transmitted only from person to person. Moreover, you can become infected without direct contact with the carrier. This happens because lice outside a person's head can live for a while. They can live without a person and move outside of his body. However, without food they will die, so their time away from a food source is limited. Let's look at how long lice live outside the human body below.

Larval development

Immediately after emerging from the egg, the larva differs little from a nit, but is larger in size. As the larvae increase in size, they go through two stages of molting, each of which ends with shedding their chitinous shell.

The process of turning a nit into an adult takes 16 days. At the end of development, the larva has formed a reproductive system and the louse is ready for reproduction. The ability of the parasite to be active increases under favorable conditions. The adult size is 2-4 mm, males are slightly larger than females. Every day an adult female lays 5-8 eggs. At low temperatures, lice reproduction slows down. But if nothing is done, lice multiply at tremendous speed.

Stories from our readers

Anna: “The hair was falling out terribly, and at the same time there was flakes of dandruff and terrible itching... in general, the complete set. For a long time I went to a trichologist, checked my thyroid gland, took tests, bought special shampoos, ampoules...whatever happened! But it was all to no avail. Perhaps now I would be left with three hairs on my head if I had not come across this article. Anyone who is concerned about hair loss, itching, dandruff should read it!” Read the full article >>

Conditions of survival

A temperature of +10 C° is an unfavorable condition for lice when the insect hibernates. At high temperatures, parasites die, but only if the heat exposure lasts a long time.

The total lifespan of the insect is about 46 days. To support life, they require blood nutrition. Without a food source, insects can live no more than two days, but usually die within 24 hours. Nits can live longer, up to four days.

The human body temperature is ideal for the establishment and reproduction of parasites. But lowering the air temperature, even significantly, will not help get rid of lice. They will die only if they are separated from their habitat in the cold.

Specifics of the method

Pediculosis is a disease characterized by the presence of blood-feeding parasites on the hair of the human body. Most often, this problem occurs in childhood. Can adults get lice? Of course they can. There is an opinion that hair dye can help adults get rid of pathology.

Features of the pathology

You can become infected with head lice from a carrier in several ways:

With direct contact. Therefore, if a child has lice, then his parents may also have them.
When using the wearer's personal belongings. For example, you cannot use another person’s combs, towels, or hats.
When visiting public places. Infection often occurs in hairdressing salons, beauty salons, swimming pools, saunas and other places.

Therefore, it is quite easy to become infected with lice. It is enough to touch the host or use his personal item and the insect ends up on the hair of a healthy person. What kind of parasite is this - a louse? This is a small parasitic organism that settles in human hair and feeds on his blood. It has a short life cycle of about 6 weeks. During this period, the individual lays several hundred eggs (nits).

There are several types of lice depending on their location:

cephalic - settle on the hair growing on the scalp;
facial - live on the coarse hair of the face - mustache, eyebrows, eyelashes;
pubic - live in the groin area;
clothes - they settle on clothes and move onto a person’s skin to bite him.

If an infection has already occurred, then the question arises of how to kill the lice. One of the means to combat pathology is called hair dye. Is it so? Do lice die from hair coloring? The answers to these questions are ambiguous and depend on which product was chosen, because not every hair dye kills lice and nits.

Composition of the product

To kill lice with paint, it must contain aggressive toxic substances that kill the parasites. That is, gentle products are not suitable in this case; lice do not die from this type of paint. Each hair dye contains a dye and an oxidizing agent. The first contains coloring pigments that do not in any way affect the viability of lice. The second one can be quite toxic. If it was decided to remove lice with hair dye, then it should contain the following components (oxidizing agents):

Ammonia. If hair dye for lice contains ammonia, then the parasitic organisms die from poisoning by chemical fumes. This oxidizing agent also has the ability to destroy the adhesive that attaches lice eggs to hairs.
Hydrogen peroxide. This is an active chemical that has the ability to destroy complex organic molecules. If it comes into contact with a louse, penetrating through its shell, it affects the respiratory organs of the parasite with toxic fumes.

So, is it possible to remove lice using paint? Does it kill parasite eggs (nits)? The answer is simple - if you dye your hair with a dye containing ammonia or peroxide, the lice will die. But the nits will remain. Since these substances are not able to penetrate the egg shell. Therefore, they must be combed out using a special comb.

Many women are interested in whether lice grow on previously dyed hair? Immediately after the dyeing procedure, lice do not appear, since the ammonia smell repels them. After just a couple of days, when this unpleasant odor disappears, the parasite appears with the same probability as on ordinary ones. That is, if the hair is dyed, this does not fully protect against lice.

How long do lice live?

When the temperature drops to 20 °C degrees Celsius, lice slow down the speed of all life processes: the development of larvae stops, and females stop laying eggs; at this temperature, the parasite can survive up to 2 days. When the temperature drops to +10 °C degrees, the lice leave the host's body, since such conditions are unsuitable for their life. Lice can die when the temperature rises above 30 °C, which will take about 24 hours. Therefore, washing linen and clothes can be used as a disinfection method.

An excessive decrease in temperature is also detrimental to parasites. It is believed that -20 ° C is a value sufficient to destroy these insects. The death of lice in the cold occurs only if they are on clothing or objects. In hair, parasites can maintain their vital activity, since body heat maintains a constant positive temperature. In such conditions, one individual can live about 4-5 weeks and lay 4-8 eggs daily.

Question-answer section

It is not always possible to find an answer to non-standard questions. If a difficult situation arises, it is recommended to consult a specialist. Below are the most common questions that users ask.

How many lice and nits can be in the hair on your head at the same time?

Elena Knyazeva, Chelyabinsk, 41 years old “When my son came from his grandmother, I saw a lot of parasites. I wonder how many insects can be on the human body?” Expert opinion Evgeniy Igorevich Bragin Entomologist, 19 years of scientific experience. “Theoretically, up to 75,000 lice, including their offspring, can live on a person. However, there is a high probability that the patient will not survive due to severe complications. In addition, the psyche suffers greatly. It’s unlikely that you can safely tolerate even a smaller number of parasites, so don’t worry, it won’t come to that in your case.”

Can there be lice on short hair?

Lice feed on human blood. They need hair in order to move freely on the head (that’s how their body is designed) and lay their eggs on it - future offspring. And the length of the hair does not play any role in this case. Parasites will feel great in both a long braid and a crew cut with a hair length of 3 - 4 mm. Only complete hair cutting “to zero” can save you from insects and their offspring.

Is it possible to get lice without human contact?

The problem of lice is quite common, so many people are concerned about the question of whether it is possible to become infected with lice without human contact?

The answer to this exciting question is yes. Let's consider possible routes of infection:

Through body items, if they were worn before you by a person infected with lice.
Through the use of combs and other styling items (this is especially common in hairdressing salons).
Through scarves and hats previously worn by a person with lice.
Through the use of bed linen in trains and hotels.
Swimming in a river (the parasite lives in fresh water for up to two days).
Classes in the pool (if a person with head lice swam there before you).
Operation of common items in a kindergarten, camp or school.

Regardless of the habitat, under favorable conditions (air temperature, humidity), the development of nits ends with the appearance of a parasite larva.

Find out more about where lice come from and how you can get infected with them on our website.

Interesting fact. An adult louse covers a distance of 50 cm in one minute. This ability to move quickly helps parasites quickly move from one person to another, even without close contact.

There is an opinion that a person with short hair cannot become infected with lice. This is not entirely true. Even a bald person can become infected with lice . But the parasites very quickly leave such a host, since they simply have nothing to cling to and lay eggs.

The animal quickly becomes infected with fleas, picking up parasites from other animals on its fur, becoming infected through sand and water. An animal cannot transmit flea nits to a person.

Can nits live in pillows?

Veronika Belova, Moscow, 38 years old “I was removing lice for my child, and now I am afraid that they will end up on the bed linen and pillows. Can insects settle on these things?” Expert opinion Evgeniy Igorevich Bragin Entomologist, 19 years of scientific experience. “Capital lice is a disease that affects only the scalp.

Parasites do not live outside the human body. They can only survive for a short time without blood, so they deliberately do not leave their victim. Insects accidentally end up on the pillow, for example, if hair falls out, and along with them, parasites. But in this case, the lice will soon die or find a new owner who will lie down on the pillow where the louse is located. Don’t worry, insects won’t live in your pillows all the time.”

Can lice live on animals?

There are several types of lice in animals:

Sucking louse - feeds exclusively on blood;
Biting louse - feeds on skin particles.

Cats can be infested with lice. For many, this reality was astonishing. But it is so. Lice, or they are also called lice-eaters, live on animals in the fur and feed not on its blood, but on the skin. Therefore, one of the symptoms of infection will be bald patches or lack of hair on parts of the body.

Dogs are also susceptible to this disease. Parasites cling to hairs and attach to the skin. They feed on the blood, sebaceous glands and skin of the victim. The pet suffers from itching and loses its fur.

Pediculosis can cause more serious illnesses. Such as wasting or tapeworm. Therefore, animals need urgent treatment.

Can you get lice from contact with animals? No! The lifestyle of these parasites is significantly different. They are adapted to higher body temperatures than humans.

Do lice live in colored hair?

Marina Inina, Krasnoyarsk, 33 years old “Tell me, if you use hair dye, lice won’t appear later?” Expert opinion Valery Aleksandrovich Galanin Acarologist, research institute employee, specializing in arachnids “The likelihood of this, of course, remains. Parasites are attracted to hair as a habitat, in any form: dyed, unkempt, and so on.

If insects appeared on the head after applying the paint, then they can calmly exist here and further, nothing will interfere with them. But it’s another matter when lice were already on your hair, and you decided to change the color. In this case, insects may die under the influence of chemicals, but the effectiveness of this method (if the paint is used as a remedy for lice) is low.” Pest eggs are found at the very roots of the hair

Do head lice live on clothes?

Valeria, Svobodny, 34 years old “I saw some kind of insect on my daughter’s things, and at that time we were just removing lice for her. Can these parasites spread, move to other parts of the body or clothing?” Expert opinion Evgeniy Igorevich Bragin Entomologist, 19 years of scientific experience. “Don't worry, it was a different insect. Lice do not leave the scalp. If they were head parasites, of course. Only body lice live on clothes. They don't live in hair, so in your situation, where head parasites have already been detected, I wouldn't worry about them spreading. You saw some other insect. Get well!"

Can lice live under the scalp?

Elena, Stary Oskol, 43 years old “My head is constantly itching, but upon examination they didn’t find anything on me. Are there subcutaneous lice?” Expert opinion Valery Aleksandrovich Galanin Acarologist, research institute employee, specializing in arachnids “I understand your concerns, but itching is a symptom that manifests itself with the development of various diseases. Among them is scabies, caused by subcutaneous mites. Visit a doctor, you need to be examined and tested. Then it will be possible to judge what caused the itching. You can write to me about the results later.”

How many days do lice live without food after treatment?

Olga, Ufa, 28 years old “Tell me, how many times do you need to treat parasites in order to remove them?” Expert opinion Evgeniy Igorevich Bragin Entomologist, 19 years of scientific experience. “Lice die quickly after contact with the poison. One procedure is enough if everything is done correctly, namely: remove insects with a comb, and it is important to ensure that no nits remain. Treatment with chemicals does not affect the ability of parasites to feed. They will either survive or they won't. If you are wondering how long a louse lives, then on the second day without food it will die. To do this, the parasite must lose its food source – humans.”

How long do lice live outside the human head?

Lice can live outside the host's body. However, this is an unusual state in which they can maintain their vital functions for a certain period. This type of insect can move on any surface. A louse can move at a speed of 20-30 cm per minute. The high risk of developing head lice in close contact with the carrier is explained precisely by the fact that these parasites crawl quite quickly.

Lice can stay outside the hairline or genitals for only a limited period. Therefore, in the absence of a host, the parasite will strive for a food source, since the lice needs human blood at least 4-5 times a day. The parasite can live without food for a maximum of about 4 days, but in most situations this period is about 2-3 days.

When the ambient temperature drops below +10 °C degrees, the lice will be able to maintain vital activity for about 24 hours. If the temperature drops below zero, this period is reduced to 2-3 hours.

How to get rid of lice?

Mechanical methods

Typically, mechanical methods mean hair cutting, shaving and combing out parasites with a comb, but they can also include thermal treatment with a hair straightener or tongs. Hair cutting at the root is the cheapest and most effective treatment method, but it is not suitable for everyone. Women and girls will not want to lose their hair, and not all men are ready to go bald.

Chemical and mechanical methods must be combined. Just treating with a drug from a pharmacy will not be enough; you need to comb out dead lice and their larvae from your hair. The fact is that most drugs are not capable of destroying nits; their shell reliably protects the offspring from chemical exposure.

Don't expect to get by with a regular comb. Nits must be combed out with a special comb with very frequent teeth located almost close to each other.

Chemicals

There are a large number of modern drugs for head lice; they differ in cost, consistency and method of application. The most common types of medicinal formulations can be distinguished:

Shampoos are the most popular, inexpensive and quite effective products when used correctly and following all the procedures specified in the instructions. Here are some of them: Hygia, Paranit, Lavinal. Shampoos specifically designed for children are sold separately.
Sprays are more effective than shampoos, but are more difficult to use, are difficult to wash off and can cause unwanted allergic reactions. Usually a comb is included. The most famous: Paranit, Lavinal, Nyuda, Para Plus.
Aerosols used to treat contaminated clothing. Someone even uses Dichlorvos against lice.
Creams are less common than shampoos and sprays, but they are not inferior to sprays in effectiveness. Among them: Nix, D-95.
Combs - designed for combing out bloodsuckers. They differ from ordinary ones in that they have very frequent teeth that detach the nit from the hair using mechanical pressure. But this is an auxiliary product used in combination with chemicals, most often included with the product.

Linen lice are removed by thoroughly washing and ironing bedding or clothing. Temperatures above 60 and below -10 °C are destructive for parasites.

Traditional methods

Although folk remedies can be recommended by most representatives of the older generation, they cannot be called particularly effective. Their main advantage is accessibility, but they can cause harm or, at the very least, be useless. Here are some common folk remedies for lice and nits.

Kerosene - smear it on your head, wrap it around your hair and leave it for 2 hours. After treatment, the substance must be washed out for a very long time, besides, it damages the hair and can leave a chemical burn on the scalp.
Cranberry juice has a depressant effect on lice and detaches nits from the hair, as the acid dissolves the adhesive. All that remains is to comb them out with a fine comb.
Vinegar 6 or 9% acts similar to cranberry juice. Take three tablespoons of vinegar per 300 ml of water and apply the mixture to the scalp. The composition dries out the scalp greatly.
A mixture of pomegranate juice and mint decoction, in a ratio of 1 glass to 3 tablespoons, is boiled for more than 10 minutes. Moisten the hair with a warm decoction and rub it into the skin.
Hair coloring will not prevent lice. Only very caustic and harmful paint can kill 40-80% of parasites. This method cannot be considered effective

All folk remedies involve wrapping the head in a towel for up to two hours. But in children it is necessary to check the condition of the skin every 30–40 minutes to avoid burns.

We do not recommend resorting to traditional recipes if it is possible to purchase a safe and effective medicine at the pharmacy.

If after one wash with an insecticidal agent and combing the insects survive, you should treat your hair again after a week. And comb out again, since initially some nits may not be combed, and larvae will hatch from them.

Prevention of lice is to follow the rules of hygiene: use only your own things, swim in the pool with a cap and avoid untidy people.

How long do lice live on clothes and linen?

The development cycle of the parasite from the larva to a healthy individual lasts 20 days, and the life expectancy of an adult insect is from 27 to 46 days. Without food, they can maintain their viability for a much shorter period:

• Death of the human louse occurs on the second day. When the temperature drops, the fasting period can increase to 10 days.
• The flies can support life outside the host’s body for about 8-9 hours, and in water for no more than 2 days.

How dangerous are parasites?

Insects do not carry dangerous diseases that are transmitted through blood. We are talking about AIDS, hepatitis and others.

However, diseases spread by human head lice include typhus. In the stomach of parasites, favorable conditions are created for the growth and further reproduction of individual microorganisms. These include the causative agents of typhus and relapsing fever. They are not transmitted to humans by a bite, as many people think. Infection occurs through excrement or when an insect is crushed. If there are small wounds and other injuries on the skin, the likelihood of developing typhus increases several times. Also, infection cannot be ruled out if the pathogen gets on the mucous membranes.

How long do nits live?

After the female louse has laid larvae on a person’s hair, the eggs must go through 3 phases of developmentname=”anchor44″>. A nit is a cocoon containing a future louse. During maturation, it does not need nutrition, so if for some reason it leaves the host’s body, it will be able to maintain its vital functions for about 8 days before hatching from the egg. If a small louse cannot immediately find food, it dies within 24 hours

For the maturation of nits, the most important is the temperature regime. If the nit is in hot conditions, the louse may hatch after 4-5 days. This is possible when wearing hats in winter, since a kind of greenhouse conditions are created under it. Therefore, after combing your hair, you need to thoroughly disinfect the entire room.

What do parasites look like and their symptoms?

A head louse is an insect whose average size reaches 1.5 - 3 mm .
It has an oblong body of gray, white, yellow or brownish color, the intensity of which depends on the degree of satiety of the parasite. The body of the louse includes 3 sections: a diamond-shaped head with a piercing-sucking apparatus and a pair of simple eyes located on it, a trapezoidal chest with three pairs of legs and an oval oblong abdomen, on which there are genitals. IMPORTANT! The opinion of those who believe that lice freely jump from head to head is erroneous. This is not so: the speed of movement of the insect does not exceed 23 cm per minute. Therefore, the parasite can get from one person to another only through prolonged close contact of heads and hair or through environmental objects, for example, a shared comb. Learn more about what a louse looks like

When it gets on the scalp, the louse begins vigorous activity, but for the first days after infection the host does not notice anything . Insect feeding does not cause any discomfort in humans. But this is for the time being...

Each louse bite is accompanied by the release of a special enzyme into the scalp, which has an irritating effect on the host : while the bites are single, the disease is asymptomatic, but with an increase in the number of parasites, numerous enzyme releases make a person feel constant itching on the head. The desire to constantly scratch your head is the main symptom of the disease.
Sometimes a person, in a desire to get relief from itching, scratches his head to the wounds , which can quickly begin to fester if infected . The presence of scratching on the epithelium of the scalp is one of the signs of the disease.
The main sign of insect damage is the presence of tiny translucent eggs on the hair, which can easily be confused with dandruff. Only you won’t be able to shake them off like dandruff: they are firmly attached by the “caring” female with a special adhesive solution.

Effective treatment

Dimethicone, which belongs to silicone oils, is widely used not only in cosmetology, but also in dermatology. This component is used to ensure that creams, serums and balms have a plastic consistency and are comfortable to apply to the skin; it also creates a protective film that helps retain moisture.

This low-hazard component has a detrimental effect on insects that parasitize humans. Lice have 4 pairs of spiracles on the lateral surfaces of the body, through which air penetrates. The larvae have the necessary supply of nutrients inside the shell, and receive air from the outside.

Dimethicone and mineral oil, which are the basis of Paranit products, are easily distributed along the entire length of the hair and tightly clog the spiracles of nits and adults. To achieve maximum effectiveness, you need to generously lubricate each strand and hair roots. The line of anti-pediculosis drugs includes a form that can be used to treat 1-year-old children and pregnant women. "Paranite" is available in the form of lotion, spray and shampoo. The oily consistency of the product allows you to apply it evenly over the entire length of the hair.

An important advantage of this drug is the lack of resistance in parasites when it is used repeatedly. The physical effect of the drug, based on the cessation of oxygen access, does not allow parasites to develop resistance. Therefore, “Paranit” will help you easily get rid of insects and keep your hair healthy.

When using medications to get rid of lice, it is worth remembering that during combing, they can fall on the floor or other surfaces and then be picked up by other family members. Therefore, it is important to use all methods of protection and get rid of lice with special care: it is better to use a comb and pediculicides in the bathroom, which can then be thoroughly washed and/or disinfected.

Getting rid of lice

Pediculosis can be cured in both humans and animals at any stage of its progression. To do this, you need to start active treatment immediately after detection of the disease. Use special shampoos and ointments; pharmacies and veterinary pharmacies offer a huge range. Or use traditional medicine.

A well-known method of treatment is also combing; it allows you to completely get rid of both lice and nits. An interesting fact is that nits can survive on a person’s head, even after being cut bald. They attach to the bulbs, are able to develop and subsequently reproduce productively.

be careful

According to statistics, more than 1 billion people are infected with parasites. You may not even realize that you have become a victim of parasites.

It is easy to determine the presence of parasites in the body by one symptom - bad breath. Ask your loved ones if your breath smells in the morning (before you brush your teeth). If yes, then with a 99% probability you are infected with parasites.

In women: pain and inflammation of the ovaries. Fibroma, myoma, fibrocystic mastopathy, inflammation of the adrenal glands, bladder and kidneys develop. As well as heart disease and cancer.

We would like to warn you right away that you do not need to run to the pharmacy and buy expensive medications, which, according to pharmacists, will eradicate all parasites. Most medications are extremely ineffective, and they also cause great harm to the body.

We suggest you read: How to get rid of bedbugs in an apartment

Prevention methods

Preventing head lice is quite simple. It comes down to observing basic rules of personal hygiene. Those with long hair are advised to wear a ponytail or tuck their hair under a hat when using public transport. You should also not use extraneous hats, towels, hygiene items, or combs.

If infection cannot be avoided, it is necessary to prevent the further spread of head lice. Bed linen, towels, and hats should be boiled and ironed. How to treat an apartment for head lice? To do this you need to use special tools. They are sold in hardware stores.

After infection, it is important to undergo examination by a dermatologist, who will prescribe therapy, and notify contact persons in the garden, school, and relatives about the disease. The recovery process should be regularly monitored by a specialist.

Appearance and characteristics of the insect

The main danger that people face when coming into contact with lice is the risk of contracting typhus. Insects are carriers of this disease. In order to promptly determine the presence of parasites, it is necessary to understand in more detail their eating habits, behavioral characteristics, and study their lifestyle.

What does a head louse look like?

Special growths on the paws help the parasite move through the hair

Parasites are distinguished by a light brown body color, but are able to camouflage themselves with the surrounding conditions (the color of the host’s hair), and the color changes to a darker one. These insects are small in size: from 2 to 4 mm. The nit is much smaller - within 0.7-0.8 mm.

These formations are noticeable on the scalp due to their white color. However, they can easily be confused with dandruff. The head louse larva is called a nymph. Parasites at this stage of development are even smaller: from 0.7 to 2 mm. The larvae have a transparent body.

Number of paws – 3 pairs. The body is segmented, and there are antennae on the head. The paws are located closer to the head, for this reason the abdomen appears larger. Head lice are characterized by the absence of wings, which means they cannot fly, nor can they jump. However, these insects move quickly. This is facilitated by claw-like segments on the paws. After saturation, the body acquires a red tint.

These are small insects that spend most of their lives on the head close to the roots of the hair.

Lifestyle and eating habits

It is not by chance that people get lice. These parasites have adapted to living conditions on the scalp, which makes it difficult for them to move to other parts of the body. In addition, this is where the louse can easily hide in case of danger. These insects live closer to the skin. Nits are often found on hair.

The food source for parasites is human blood. To get it, head lice pierce the skin, and at the same time a blood vessel. The greatest difficulty for these insects is that the vessels are not equally accessible in all areas. However, during evolution, parasites have identified the most vulnerable places: in the neck area, behind the ears. This is where you should look first.

The parasite sucks about 0.5 mg of blood at a time and feeds every 4-5 hours.

The frequency of meals is every 4-5 hours. In this case, in one approach the insect sucks out 0.5 mg of blood. The process is facilitated by a special enzyme that the parasite introduces at the stage of piercing the human skin with its proboscis. Thanks to this feature, the rate of blood clotting is reduced. This is the cause of allergic reactions after a bite: redness, itching. Waste products are easy to notice on the scalp - these are small black dots.

How do lice reproduce?

Insects form oviposition on human hair. On average, an adult head louse can lay approximately 120 eggs in its lifetime. Considering that the lifespan of an insect is no more than 40 days, the female reproduces 3-4 eggs every day. The incubation period lasts 5 days, the nymph develops to an adult in 10-15 days, which is determined by living conditions. So, the lower the temperature, the longer the development process of insects takes.

Nits are white in color and due to constant hair growth, they become more noticeable over time.