Lice and their guides are unpleasant, but quite common. The insect is a small wingless ectoparasite with three pairs of tenacious legs. With them, it reliably attaches to human hair, on which it places its eggs - nits. They are easy to see on close inspection of the head. The time interval during which the development of eggs and the appearance of adults occurs is called the incubation period of lice and nits in humans.
Ectoparasites feed on blood, piercing the skin of their victim. They are carriers of dangerous infectious diseases, including typhus. The phenomenon associated with the appearance of pests on the hairy areas of the body is called head lice and requires immediate treatment.
How does the infection take place
Lice are wingless insects, they cannot fly, and they jump a very short distance, therefore infection occurs through direct contact with a sick person... Children aged 3 to 10 are most susceptible to head lice, since in kindergartens and schools they have close contact with other children.
You can get lice:
- in public transport, if there are a lot of people and everyone is close to each other;
- in changing rooms, swimming pools, gyms, etc .;
- in kindergartens and schools;
- using personal hygiene items of an infected person (comb, hairpins, towel);
- putting on someone else's clothes;
- during intercourse with a patient with head lice.
It often happens that lice remain on the bedding and then crawl from there onto the head of a healthy person.
Important! Nits (lice eggs) can remain on even the smallest hair clip, so it is not recommended to take such things from other people.
There is an opinion that head lice is characteristic of those who do not follow the rules of personal hygiene, but in fact, lice rarely settle on a dirty head, they are comfortable living in clean hair.
Reference! Pets cannot infect a person with lice, since these insects do not live in animal fur.
The body louse does not live directly in the hair of a person, it prefers folds of clothes and bites a person when he wears these clothes.
Life cycle of parasites
The life cycle of all three types of lice is almost identical and differs only in some minor nuances. On average, a louse lives 30-40 daysand then dies. In such a short period, one individual can lay a large number of eggs, but this number is different for each species:
- the head louse lays 70 to 150 eggs;
- pubic - 40-50 eggs;
- The body louse is the most fertile and lays up to 300 eggs per life.
The entire life cycle of a louse can be divided into 6 full stages:
- nit;
- larva;
- nymph of the first age;
- nymph of the second age;
- nymph of the third age;
- an adult.
The complete process of transformation from a nit into an adult takes on average only 16 days and can take up to 30 days if the conditions for the development of the insect are unfavorable.
Between the stages of development, an average of 4 to 6 days pass, and as soon as a sexually mature insect is born, it can immediately begin to lay eggs.
Reference! Lice are insects with incomplete transformation, i.e. they do not have the typical larva stage.Most other insects have this stage when the larva differs from the adult both in appearance and in the type of feeding.
During the transition from one stage of the life cycle to another, the chitinous membrane is discarded, or molt. This is necessary for lice due to the fact that with the growth of the insect itself, its hard shell remains the same in size. On average, the duration of one molt takes only 3-5 minutes, after which the louse can immediately begin to feed on human blood.
Such a rapid development of this species is due to the fact that they actually live on their food source and never starve.
At the first stages of insect development, it does not have any sexual characteristics, they appear later, depending on which insect sex is not enough.
Duration
The delay in the onset of symptoms depends on the type of lice, environmental conditions. Similar factors affect the rate at which nits develop. Head lice, body lice, develop from an egg to an adult insect in about 20 days (favorable conditions are required). In the pubic species, the process proceeds somewhat faster: about 18 days.
The incubation period of lice (the appearance of noticeable symptoms) is highly dependent on the conditions characteristic of the development of the insect offspring. Lack of food is rare for lice. It is typical, mainly, for the wardrobe (it is necessary to change the linen by the wearer). For this reason, the slowdown in development, death is rare.
Incubation period
The incubation period of the disease in medicine is considered to be the time that passes from the moment of infection until the first signs of the disease appearbut this does not quite fit the description of the incubation period. When infested with lice, this period is considered the period of development of lice eggs.
Lice begin to bite a person as soon as they hit his head, but in most cases there are only a few individuals and the bites are not felt. If the scalp is thin and sensitive, then the patient will feel a slight itching, but is unlikely to pay attention to it.
But, since lice multiply very quickly, after 3 weeks the second generation of insects will appear and their number will be enough to bring a lot of trouble to their owner in the form of itching, abscesses, spots and allergies. That is why the incubation period of head lice is considered to be 21 day.
The development of body lice can take 50-60 days, depending on how often a person changes clothes and bedding. For example, if he walks in the same clothes all the time, then the nits will very quickly go through all the stages of growing up.
Important! The incubation period may also change depending on the conditions for the development of lice. For example, if an infected person lives in a country in a cold climate and often wears a hat, but takes it off in a well-heated room, then insects develop faster. But in people who live in temperate climates and walk with their heads open, lice develop much more slowly.
Destruction of nits
Lice drink blood, nits are unable to do this. For this reason, many people think that adults are the most dangerous.
In fact, it is much more difficult to kill nits than hatched larvae and adult lice. Even after the most careful processing, the eggs are able to survive. Soon, new individuals hatch from them, and the disease returns.
Shampoos, aerosols and emulsions
To fight the disease use pediculicidese shampoos, aerosols and lotions... Healing shampoos are used in the same way as ordinary shampoos, but they are left on the hair for a while for effect. Aerosols are sprayed onto dry curls. The emulsions are diluted with water and also applied to the hair, left on for 40 minutes and washed off. Then, with the help of special combs, the dead bloodsuckers and their eggs are combed out.
A number of pediculicides are sold in pharmacies that are designed to get rid of lice.
All of these tools are pretty easy to use. Most contain insecticides such as permethrin. It does not affect warm-blooded animals, but it is the strongest poison for insects: it affects the nervous system, paralyzing them. Then the parasite suffocates.
With adults, all these tools cope very well. Unfortunately, they are powerless against nits. Insecticides affect the nervous system, and eggs are not yet fully formed. Nits remain alive and new individuals appear on a clean and clean head.
The incubation period of nits is on average a week. Therefore, pediculicidal shampoos and aerosols will have to be reused after 8-10 days. This is necessary to kill the hatched larvae. This must be done before they grow up and begin to reproduce themselves.
Exposure to temperatures
It is believed that nits can be killed by exposure to low or high temperatures. If the body temperature drops to + 23 ° C and below, the eggs die within 40 minutes. But even if you spend an hour without a hat in a severe frost, you will not be able to reach this limit.
When eggs are heated to + 50 ° C, they quickly die. For these purposes, you can use a hairdryer. Unfortunately, before all the eggs die out, there is a high risk of heatstroke from the hair dryer.
The method can be used as an additional one, for a safety net, but not as the main one.
Guaranteed Ways
Only a mechanical method - combing eggs - is able to give a 100% result. For these purposes, special combs with metal teeth tightly fitting to each other are used. This is a painstaking and time-consuming method, but the most effective one.
Plastic prongs are not suitable as they bend easily and nits can pass through them. Short prongs won't work either. There are also electronic combs on sale that combine the function of a vacuum cleaner.
When starting the combing procedure, you need to know some of the nuances:
- Combing is carried out only after shampooing on wet hair. Before that, the hair must be treated with a medicated shampoo, emulsion or aerosol.
- Brushing out can be made easier by applying a little balm, olive oil, or tea tree oil to your hair. This will greatly facilitate the sliding of the ridge.
- Prepare a bright lamp in advance.
- It is recommended to comb the hair over a light-colored cloth to see any parasites or fallen nits. At the end of the procedure, carefully wrap the cloth so that insects and their eggs do not fall to the floor. Put everything in a plastic bag and throw it away.
- Prepare a bowl of water in which you want to clean the comb.
- Those nits that are strongly attached to the hair and cannot be removed should be cut off with nail scissors.
- The water from the bowl should be flushed down the toilet periodically.
- At the end of the procedure, wash your hair with regular shampoo. Boil the comb.
There is another way that is guaranteed to get rid of nits and lice. This is shaving your head. The method is really radical, but it works. It is not quite suitable for women, but men may well use it.
Shaving your head is a proven and radical remedy for head lice.
Treatment of head lice should be started as soon as the insects are found. Adult parasites will be destroyed by insecticides, and nits can be removed mechanically. While there are not many of them, this is easy to do. The more the disease is started, the more difficult it will be to destroy all the nits.
How to identify the disease in time
It is very difficult to detect head lice in the first days after infection, since the bites of several individuals are almost invisible. It is much easier to find lice eggs on the hair, for this it is necessary to periodically examine the head for prevention.
Nits can often be confused with ordinary dandruff, as they have the same size and are similar in color, but the eggs are tightly attached to the base of the hair, and it can be difficult to remove them, unlike dandruff. When pressed, the nit bursts with a characteristic cracking sound.
You can detect the presence of insect eggs on the head with a comb with very fine teeth; when combing, the nits will remain between them. In this way, even an adult louse can be detected if the hair is wetted first. Lice remain immobile in wet hair.
You can determine head lice and the main features:
- debilitating itching in the scalp, especially above the ears and in the back of the head;
- multiple scratching, which contributes to the development of acute dermatitis;
- small spots of gray-bluish color on the head;
- the appearance of inflammation and papules at the bite sites.
With advanced head lice, the hair takes on a putrid odor and an untidy clumping appearance. At the same time, shampooing helps for a short period.
Conditions under which lice breed
The conditions for the development of nits of these insects have a very limited temperature regime. The optimum temperature for their rapid development is 30-32 degrees Celsius, but at temperatures below 22 degrees and above 45 degrees, their development completely stops. At the same time, eggs can be stored for up to 1-2 weeks without damaging the larva, since the outer shell protects them well from adverse conditions.
Lice cannot live for a long time without food, that is, without blood, but this period is different for each species:
- head and clothes can last up to 3 days without food;
- pubic lice without blood die after 10 hours.
But the lower the ambient temperature, the more time the lice can survive without human blood.
Preventive actions
Even when it became clear why the head may itch, if there are no lice, it is advisable to treat the skin to reduce discomfort. Prevention of causeless itching should be comprehensive and can be limited to folk recipes.
Ingredients:
- chamomile - 2 tablespoons;
- a series - 2 tbsp. l.;
- boiling water - 1 liter.
Boil over low heat for 1.5-2 minutes, leave for half an hour, then strain and rinse your hair in the morning and evening.
You will need:
- chopped Hercules - 0.5 tbsp.;
- boiling water - 1 tbsp.
After swelling, the gruel is applied to the scalp, left for half an hour and washed off with cool water.
A well-known soothing and regenerating agent that is added to water before rinsing. Be sure to pre-check if there is an allergy to the oil.
How to treat head lice
Previously, in most cases of infestation with head lice, people had to shave their heads, but now there are many ways and means to get rid of hair from lice and nits. Treatment can be carried out independently at home, or you can contact a specialist to prescribe medications.
Treatment of head lice with high temperatures
This method is very effective and ideal for self-treatment, since almost everyone has a hairdryer or an iron at home to straighten their hair. Due to the fact that lice die at temperatures over 50 degrees Celsius, thorough hair treatment with a hairdryer or iron can kill them.
To do this, you need to carefully process the strands one by one, not missing a single infected area. After treatment, it is advisable to wash your hair with a special shampoo.
Chemical treatment
Pharmacies sell a large number of products aimed at combating lice and nits. They are available in the form of balms, sprays, shampoos, creams, solutions, gels and ointments. These funds contain components that destroy the nervous structure of insects.But their effectiveness is not 100%, since they act directly on the lice, and not on the nits.
Means, which include dimethicone and cyclomethicone, act on a different principle, they envelop both lice and nits with a thin strong film that does not allow air to pass through, as a result of which insects die. These drugs are highly effective, but can cause allergies.
Before buying this or that medicine it is recommended to consult a doctor, especially if children under 6 years of age and / or pregnant women are being treated.
Treatment with folk methods
The people know dozens of ways to deal with annoying parasites, including:
- petrol;
- kerosene;
- dichlorvos;
- vinegar;
- hydrogen peroxide;
- laundry soap;
- decoctions of poisonous plants;
- and much more.
Most of these methods can harm a person, lead to burns, hair discoloration or complete hair loss, poisoning with poisonous vapors and allergies.
Important! It is not recommended to start treatment of head lice with folk remedies, since their effectiveness is much lower than the effectiveness of specialized drugsbut there are many more side effects.
In the modern world, head lice is not considered a disease of "dirty" and "sluts", since absolutely anyone can get it. Treatment should be started immediately, as soon as nits were found in the hair, since it is not difficult to remove them when there are few of them, but after 1-2 months a horde of insects will deliver a lot of suffering to their owner.
Recommendations for the use of pharmacy remedies for lice
First of all, you must follow the instructions. Only 1 drug should be used so as not to cause allergic reactions in the patient due to the high content of toxic substances. It is enough to apply the purchased product only once. If the affected areas are subjected to repeated treatment with the drug, then the risk of developing intoxication is high.
The room where there is a person infected with head lice must be regularly ventilated.
Before starting the treatment of the scalp, a bandage should be put on the patient to avoid getting the drug on the face and eyes.
It is forbidden to use ordinary shampoos or balms without first applying a medicinal product, since after their use a thin film forms on the skin, preventing the penetration of medicinal products onto the upper layer of the skin.
During the incubation period and during the treatment of the disease, it is not recommended to use a hair dryer to dry your hair.
