Head lice or head lice

Head lice are called head lice. They are one of the subspecies of human lice. As the name implies, they live in the hair of a person, but sometimes crawl onto a beard, eyelashes and eyebrows. Head lice are small and inconspicuous. Finding them in your hair is extremely difficult. In addition, they lead a sedentary lifestyle and spend most of their time clutching a hair in their claws and freezing.

The appearance and development of insects

Head louse is a strictly specialized parasite. In the process of evolution, he adapted to life on a certain part of the human body - the head. It has an elongated body shape that helps to move freely along the hairline and tenacious paws ending in sharp hooks resembling claws of a claw. All this contributes a lot to his life and prosperity of the species.

Appearance and structure

What do lice on the head look like? Outwardly, these are rather small brown insects, not exceeding 4 mm in length. They have tenacious paws and a piercing-sucking-type oral apparatus adapted to pierce the skin and pump blood into the abdomen of a bloodsucker. Lice have no wings. They lost them as unnecessary, but instead got sharp claws at the ends of the legs and spines located on the entire surface of the body. They help the parasite to stay on the hair and not fall when moving.
The body of the head louse is elongated. This form does not interfere with the parasite during movement and helps it hide between the hairs. The eyes are simple, dark in color, located on the sides of the head. Below are two pairs of short jointed antennae that perform the function of a tactile organ.

Interesting fact! The head louse is able to move quite quickly. In a minute they are able to cover a distance of 35 cm, which is a pretty impressive result for such a small insect.

Development and reproduction

Head lice are synanthropes. The development cycle of these insects is closely related to humans and has the following stages:

• egg
• larva
• adult insect.

Head eggs lice (nits) - about 0.8 mm in length. They have a whitish color and are clearly visible to the naked eye. Outwardly, they look like very small white droplets and are one of the main signs indicating that head lice are wound in the hair. The incubation period of the embryo highly dependent on ambient temperature. In favorable conditions, at 37 ⁰With high humidity and it is able to develop in 4 days. At 26 ⁰With the development period increases to two weeks or more.

The larva or nymph is very similar to an adult insect, but inferior in size to it. The average body length of the larva is from 1 to 2 mm. For all the time of its development, the nymph throws her skin three times, each time noticeably increasing in size. In total, the period of the larval stage takes from 10 to 14 days.

An adult louse is capable of procreation a day after molting. She mates with the male and begins to lay eggs. A female is capable of producing up to 4 eggs per day. In total, in her entire life, which is 27 to 30 days, she deposits about 150 nits.

Interesting fact! Head lice enhance hair growth. The itching provoked by them causes a desire to scratch. A kind of massage, according to scientists, causes a rush of blood to the hair follicle and, accordingly, a better supply of it with nutrients.

Symptoms of Pediculosis

Lice in the hair are almost invisible to the human eye. This is facilitated by their microscopic dimensions and masking color. However, there are still symptoms by which pediculosis can be determined even in the early stages of development.

Symptoms of the disease:

• severe itching on the scalp;
• scratches, scratches;
• traces of bites in the form of small red spots;
• nits on the hair;
• adult insects and their larvae.

You should be wary already with the appearance of the first sign - itching. It is caused in response to skin irritation by the saliva of the parasite, which it excretes during a bite. Itching is sometimes so severe that it leads to scalping of the skin on the head. Pathogenic microflora gets into the wound, which in turn can cause serious inflammation and the formation of pustules.

Nits and live insects are a clear sign of illness. You can find them by careful examination of the head or combing hair with a thick comb. At the same time, the nits are clearly visible to the naked eye, but they are almost impossible to comb out. Adult insects, on the contrary, are almost indistinguishable in the hair, but are clearly visible on a light sheet of paper, which should be put under the head before combing.

For a more detailed description of the symptoms of pediculosis, as well as complications that may develop against its background, look in the article: What are the symptoms of lice?

Interesting fact! Pediculosis most often affects nervous, emaciated people. Well-off and calm owners do not like insects for something. There is information that lice disappeared by themselves after some time, after a person’s life returned to normal.

Causes and ways of infection

How are head lice transmitted? This occurs in case of direct contact with an infected person or through personal hygiene items. The spread of the disease also contributes to some factors related to human living conditions.

Causes of head lice

Factors contributing to the spread of pediculosis are:

• low living standards;
• lack of awareness of the ways of infection and methods of treating the disease;
• unsanitary living conditions;
• crowding and unwillingness to wash.

Pediculosis, or lice, is entomosis. In some cases, it can be complicated by the addition of a bacterial infection, a viral disease, and nervous diseases. Contributing factors greatly aggravate the course of the disease.

Lice Transmission Routes

Head lice can be transmitted in the following ways:

• in contact with an infected person;
• through personal hygiene items - combs, hairpins, towel;
• when resting on a pillow on which a person with a head lice slept;
• through clothes and hats;
• when swimming in public water.

The main transmission method is direct contact. Other pathways of infection become possible only if insects enter the external environment shortly before contact. This is because, as a rule, the life span of head lice outside the human body does not exceed 2 days. That is how much the parasite can withstand without food.