How do lice look on the head, where do they come from, and is it possible to get them from pets or in the pool

Louse - a blood-sucking parasite that lives on the body of mammals, including humans. In nature, there are several varieties of insects, but each species can parasitize only in its habitat. For example, a human louse will never settle in a dog’s coat.

What lice and nits look like

How to initially understand which dead and how to identify and recognize which louse is living? For the prevention and treatment of parasites, it is important to know how lice are transmitted from person to person, to have an idea of ​​the appearance and lifestyle of pests.

Species of parasites

A person can be “attacked” by three types of lice:

• head - parasitizes in the hairline;
• pubic - lives on the pubic hair, sometimes on the armpits, less often on the eyebrows and eyelashes;
• wardrobe - "lives" in the folds and seams of clothes, bedding.

What are the differences

The head louse parasitizes in human hair, and nits are often wound up. Some believe that nits are a separate species of parasites that suck blood, others say it's the same thing. Such points of view are erroneous. To effectively combat parasites, you need to know how lice differ from nits.

A louse is a gray-brown bug with a size of 0.4-6 mm, with six legs. Nits - a louse egg coated with a special shell. The "cocoon" has a fusiform shape and a "lid" through which a ripened larva emerges from the capsule. Below is a belt wrapping an egg and hair to which it is attached. The length of the nits is 0.7-0.8 mm, the diameter of the capsule is about 0.4 mm.

Insect life cycle

The life cycle of head lice, which lives in human hair, consists of four stages.

Fertilization and egg laying

Louse is capable of giving offspring, whose age is about two weeks. After fertilization by the male and “meal”, the female lays eggs. It happens like this.

• Egg ripening. While the louse moves upward through the hair, the egg descends through the oviduct in the body of the insect, passing through the glands that cover it with a special composition.
• Egg yield. By secretion, the egg, leaving through the anus, is attached to the hair at a distance of 2-3 cm from the root.
• Attachment to the hair. After a few minutes, the shell becomes so strong that it is not even possible to remove the nits from the curl with nails.

Larval development

In a cocoon, the larva develops in five to eight days. Ripening time depends on environmental conditions.The most favorable temperature for nits is 33 ° C. When the indicator drops to 22 ° C or rises to 40 ° C, the development of the insect stops.

At temperatures above 45 ° C, the larva dies, at 0 ° C it can last two to three months. However, even in winter, the temperature of the scalp in a person rarely drops below 25 ° C, so lice can successfully develop all year round.

Exit capsule

The ripened larva squeezes the lid of the cocoon and begins to breathe. Inhaled air passes through the esophagus and escapes through the anus and accumulates in the lower part of the membrane. Under pressure, the larva is expelled from the cocoon. The process of "birth" takes only a few minutes.

Converting to Adult

The larva emerging from an egg resembles an adult, but is smaller in size and is not able to give offspring. Within 14-16 days, the insect grows, during this period three molting occurs. After the latter, the pest is able to breed, which it does, almost immediately mating with an individual of the opposite sex.

What is dangerous pediculosis for a person

If louse parasitizes on a person’s head, we can talk about a disease such as head lice. Its danger to humans is associated with five factors.

1. Danger of contracting dangerous diseases. Pests are carriers of typhoid, trench fever, but in modern conditions this is rare.
2. Wound Infection Probability. Lice leave bite marks on the skin through which infection can enter the bloodstream.
3. Dermatological lesions. Traces of bites provoke the appearance of bluish spots, allergic reactions, sometimes - pustular formations and pyoderma.
4. Discomfort. Finding lice on the head is associated with constant itching and burning.
5. Difficult social contacts. When communicating with other people, a person who has lice in his hair feels awkward. In addition, it is dangerous for others, since there is a high risk of infection.

How can I "pick up"

How do people get lice and how do I know if there are lice on my head? Doctors have figured out where lice come from in a person, and how they crawl from a "sick" head to a "healthy" one. Two pathways of pediculosis infection were identified.

1. From person to person. Most often, insects are transmitted in this way. This happens if people share the same bed, sit close to each other.
2. Through personal hygiene items and clothing. When sharing towels, combs, hairpins and rubber bands, pests also “travel” from head to head. You can get infected if you put on a hat, a jacket with a hood or other clothes that a person with lice wore.

"Risky" public places

You can pick up lice anywhere by close contact with an infected person or by using his personal belongings. Most often this happens in:

• schools;
• kindergartens;
• public transport;
• movie theaters.

Pediculosis can be infected even in places of public bathing, for example, in the pool. In poor areas of India, infection often occurs while swimming in the river.

Common myths

Some word-of-mouth information about lice is erroneous. Here are the five most common myths.

1. Lice can jump. Head-to-head lice do not jump, they can only crawl. Therefore, talking with a person at a distance of a meter, it is impossible to become infected with pediculosis.
2. Unsanitary conditions are one of the causes of lice. Insects cannot emerge from the dirt, uncleanliness only indirectly contributes to infection with head lice if hygiene rules are not followed. Absolute cleanliness in the apartment and shower twice a day do not guarantee protection against pests.
3. Head lice can be picked up only from children. Insects are also transmitted from an adult.
4. Pests can be infected by pets. Human louse does not live in animal hair, and dog or cat lice also cannot settle in people's hair.
5. Insects do not parasitize dyed hair. Most paints contain hydrogen peroxide, which is toxic to pests. However, the amount of substance is not enough to destroy or impede the viability of lice.

Incubation period

How many nits do lice come from? In biology, the incubation period of insects is the time for the development of lice eggs. In medicine, the incubation period of a disease is the period between infection and the onset of symptoms. For an entomologist, the incubation period of lice and nits is five to eight days, for a person who “picks up” parasites, three to four weeks.

How to detect uninvited "guests" ...

The very first sign of head lice is itchy skin. After a bite of a pest, a wound forms in which its saliva enters, causing irritation. When there are few lice, the itching is minor, it is rarely associated with the presence of insects. However, the more they become, the more intolerable these feelings are.

The appearance of itching does not mean infection with head lice, only the detection of insects and nits can confirm the diagnosis. Adult lice are quite difficult to see: they live on the skin and move quickly. Most often, nits are the first to be detected. You can see light capsules with eggs with the naked eye, they are especially noticeable on dark straight hair. Sometimes nits are mistaken for dandruff.

... and distinguish from dandruff

You can distinguish dandruff from nits on four grounds.

1. Amount. The amount of dandruff is always approximately the same, while the number of nits increases day by day.
2. Appearance. Dandruff flakes can be of various sizes, reaching 5 mm, the size of nits is approximately the same - not more than 0.8 mm. A closer look through the shell of the nits reveals a dark egg, the empty capsule has a yellow or gray tint. Dandruff is always uniformly white.
3. Sound. If you press on the nits, you can hear a characteristic click.
4. The quality of the "coupling". Dandruff can be easily brushed off with curls, while nits are firmly connected to the hair.

How to inspect the head

Detecting lice can be difficult, especially if the hair is blond and curly, or there are not so many pests. You can watch on the Internet from the photo how they appear. Pictures and photos may not always show how lice spread. The only sure way is combing with a special comb with frequent teeth. They can be white and black. What the nit looks like can be examined under a microscope. But it is advisable to entrust the examination to medical staff, but you can carry out the procedure at home.

How to act

1. Settle in a well-lit place.
2. Comb the hair with an ordinary comb, separating the tangled curls.
3. Comb one strand with a special comb with frequent teeth.
4. Immediately after combing, wipe the tool with a white cloth or cotton pad: lice and nits, if any, on the head will be noticeable on a light background.
5. To comb through several strands in this way.

Knowing what lice look like on your head, it’s easy to find them. The most difficult thing is to get rid of insects, and you need to do this immediately, because the fewer parasites, the easier it is to remove them.