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.

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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.

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

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.

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 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.

Appearance Features

You can see the body structure details common to all types of human lice; they do not differ significantly from each other.

Despite the lack of eyes, this insect is photosensitive. A well-fed parasite will try to hide from the light, but a hungry one, on the contrary, will come out.
The olfactory organs of lice are small antennae, with the help of which the parasites find their prey. Recent scientific research has shown an interesting fact. Household, human lice select a host based on their scent preferences, that is, by smell. Therefore, there are people who are not afraid of these parasites; lice are not attracted to their body odor.
Having sensed a suitable body odor, the parasite can feed all day long; day or night does not matter to them. They do not have a rest period, like bedbugs, which feed on human blood only at night.
The mouth of this parasitic insect is a small retractable proboscis, sharp enough to bite through the skin. The body of an insect can be roughly divided into the head and abdomen.
The species of these parasitic insects belongs to the winged insects, but in the process of evolution the wings became very small in size, because lice feel great without them.

We suggest you read: How many wings do cockroaches have?

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 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 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.

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.

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.

FAQ

To dispel doubts and prejudices, here are a few frequently asked questions to consider.

Lice and pets: is coexistence possible?

Finding out how long lice can live outside of humans, some believe that pests, in search of food, can move to domestic animals - dogs, cats. However, numerous studies have shown that this form of parasitism is impossible for a number of reasons:

lice eaters that live on dogs have longer stylets, specially adapted to bite through skin that is thicker than that of humans;
Cat lice choose this type of pet exclusively for their habitat.

It is important to remember that even if the lice eaters of one of the four-legged animals land on a person’s head, they will not stay there for long and at the first opportunity they will return to a more suitable source of food

Is the bed suitable for head lice?

Bedding, no matter what material it is made from, is not a habitat for lice. The reason for this is the inability to lay nits. Of course, sometimes you can see an insect, for example, on a pillow. But it got there by accident, falling from the head, and will leave it as soon as contact with a person is available

This is why it is so important to observe personal hygiene rules if one of your family members is found to have lice.

Can lice live on lost hair?

Some people, based on the fact that lice cling tightly to hair with their paws, believe that these insects can survive on dead curls. However, such a judgment is deeply erroneous.

Hair is not a source of food for insects. They cling to them solely to prevent them from falling while moving, washing, or combing. Accordingly, cut hair that has fallen out is not of interest as a source of replenishing energy reserves.

It is convenient for lice to lay nits exclusively on long hair. That is why they extremely rarely settle on mustaches, beards, and eyelashes. Such hair is of no interest even for pubic lice, since it is too sparse and removed from voluminous, large sources of nutrition - veins and arteries.

Knowing important points about lice, you can prevent infection, and if it does occur, you can quickly take measures to remove the parasites.

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.

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.

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.