Latin: Pediculus capitis
Lice belongs to the group of parasites that suck blood on various mammalian hosts. In humans, there are three different types of lice that have adapted to us, and the head lice (Pediculus capitis) has gradually become a true classic that most people have become acquainted with during their lifetime.
Appearance
The head lice are a flat little insect with an oblong oval shape. They are quite small, and an adult louse grows only between two and three millimeters long. As it is often the case in the insect world, the male is slightly smaller than the female.
A head louse is equipped with three sets of legs in front of the body, and each leg ends in a kind of claw. This claw is designed to be ideal for gripping a strand of hair. The head lice have no wings and can therefore neither fly nor jump. Their head is equipped with a pair of antennae and small eyes.
The mouth parts of the lice are built to bite and suck blood. Their appetite for blood has a visible effect on the color of the head lice, as the lice can appear much darker right after it has ingested blood, where the usual color may otherwise be almost transparent grayish white.
The head lice’s eggs are approximately 0.8 millimeters long and are located on a kind of “stem” that is attached to the hairs at the very bottom of the scalp. The small newly laid eggs can therefore be difficult to spot when they are firmly attached to the scalp.
When the lice are fully developed inside the egg, it pushes a small lid off the top of the egg. The newly hatched lice are quite small and measure just between 0.5 and one millimeter. When the lice leave the eggs, they stay out on the hair shaft, where they grow out with the hair and at the same time become more visible. These eggs are whitish. However, dark-colored eggs can also appear on the scalp, and this type of egg usually contains dead lice embryos. As a rule of thumb, eggs that sit more than an inch from the scalp will usually be hatched eggs or eggs with dead lice embryos.
Biology and behavior
The head lice prefer temperatures around 30 ° C, easy access to food and high humidity, and here the scalp is ideal. For the lice, it does not matter if the hair they are in is clean or dirty. For them, it is all about having an inexhaustible source of blood that they can use several times a day.
The temperature and conditions in the scalp are also optimal for the lice to lay eggs, and the process from egg to small nymph will be able to take place within 6-9 days under these favorable conditions. As soon as the little lice has come out of the egg, it will immediately start sucking blood from the scalp. If it cannot do this, it dies within quite a few hours. The nymph manages to change skin three times before it is fully grown.
The life cycle of a head lice is quite short. From the moment a head lice female comes out of the egg, until she dies, it takes about three weeks. Already after 9-12 days after the female lice have hatched, she can even start mating and laying eggs. And until her death, she can lay between five and eight eggs a day.
As described, lice can neither fly nor jump. But that does not mean that they cannot move quickly around the hair. For this purpose, they use their claws, which they use to hold on to the hair strands. Should the lice risk falling off its host, it can survive for about 48 hours before dying.
It is not because they are leaving their homes voluntarily. But they can easily find a way to move on to a new head if the opportunity presents itself. Therefore, it is also close contact between people that is the reason why the infection with lice spreads. At the same time, studies show that long-haired people are at greater risk of contracting lice than short-haired people.
Damage
Getting lice can be associated with some form of taboo for many people. But there is nothing to be ashamed of. Lice are not a sign of illness, lack of cleaning or poor hygiene. For lice, as described, are just as happy with freshly washed hair as dirty hair. On the other hand, it is important to talk openly about a possible attack, so that you can best solve the problem and launch a thorough fight against lice.
But even though lice cannot transmit diseases or are dangerous, there is no doubt that they can be a rather annoying acquaintance. The lice spit a special secretion into the wound when they suck, which can cause itching and irritation of the scalp. And if you are repeatedly hit by lice, it can lead to wounds and infections of the scalp. In such cases, you should consult your doctor.
Prevention and pest control
Prevention against lice is most effective if you regularly comb your hair with a comb. Like once a week. If you find signs of lice, you should start treatment as soon as possible and inform the nearest circle of friends you have had contact with, in case they may also be at risk of being infected. Lice are controlled with a lice repellent and / or a comb. There are various lice remedies on the market that can be purchased at the pharmacy, so be sure to read the instructions for use thoroughly before starting treatment.
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