Head Lice: Symptoms, Treatment and Prevention

Infestation with head lice (linden disease) means colonization of hair by head lice (Pediculus humanus capitis) and it generally affects only the head or scalp of the human host. Head lice feed on human blood. The itching caused by lice bites is a common symptom of this condition. The treatment involves the application of local insecticides, such as pyrethrin or permethrin, or various naturally occurring remedies commonly used.

Infestation with lice, commonly called pediculosis or linden disease, occurs in several species of mammals and birds. The term pediculosis capitis, or short pediculosis, is sometimes used to refer to man-specific pediculosis caused by P. humanus capitis (infestation with head lice). People can also be hosts of two other species of lice - corpus lutes and crab lice.

In general, infestation with head lice is an endemic condition, especially in the case of children. This generates some concern for public health, although unlike the lice, the head is not the carrier of other infectious diseases.

It has been suggested that in the past, head lice infection was a beneficial condition for both sides, contributing to the defense against the body louse, much more dangerous due to the illness it can carry.

Head Lice: Symptoms and Signs

The most common symptom of infection is itching at the head, which normally intensifies 3-4 weeks after the initial infestation.

The bite reaction is not very strong and can barely be seen among the hairs. Bites can be seen especially in the neck area, in the case of long-haired individuals when the hair is tight up.

Very rarely, itching can lead to a secondary infection with impetigo and pyoderma. Seldom lymph nodes and fever may occur. As far as we know, head lice do not transmit pathogenic microorganisms.

Head Lice: Causes

Usually head lice are transmitted by direct contact at the head with an infected person, forwarding as a consequence of the use of bedding or clothing such as, for example.

Hair-to-hair transmission is much less common but possible.

Body lice spreads through direct contact with the body, clothes, or other personal things of a person infested with lice.

The pubic lice are often transmitted by sexual intercourse with an infected person.

Head lice do not affect pets or other animal species. They have no wings and can not jump.

From each egg or linden can hatch a larva that will develop into an adult lice. At maturity, the lice have the size of a sesame seed. The lice feed with blood around 8 times a day by pricking the skin with their tiny mouthpieces, similar to the needles. The lice can not penetrate under the skin.

Head and body lice have a similar look, although the head lice are usually smaller. Instead, pubic lice look quite different. The body is smaller and has claws like pliers observed at crabs. Unlike other forms of lice, the head lice do not transmit diseases.

Heads Lice: Diagnosis

Combing wet hair using a comb for lice and balm for diagnosis and treatment. Head lice can be seen in the foam.

Diagnosis depends on the presence of lice or their eggs in the hair, its setting being facilitated by the use of a luff or by combing the baby's hair.

In unsafe cases, the child can be referred to a doctor. However, in this case, an excess of positive diagnoses is recorded, with inactive infestations being confused with some active.

Consequently, lice killings are often used on uninfected children. Using a comb against lice is the most effective way to detect living lice. In cases where children have long hair and/or curled or wrinkled hair, an alternative diagnostic method is examining the head by dividing the hair into strands at 2 cm intervals to discover lice that travel to the scalp.

In both methods, special attention should be paid to the area near the ears and the neck.

The examiner should examine the scalp for at least 5 minutes. Using a magnifying glass to examine the material collected between the comb teeth could avoid making the wrong diagnosis.

However, the exclusive presence of lindens is not a clear indication of an infestation with active head lice.

In the case of children who have lindens in hair, the possibility of being infected with living lice and eggs is around 40%.

If lice are detected, the whole family should be checked, especially children up to 13 years of age, using a louse comb and those who are infected with active lice should be treated.

If no living lice are detected, the child should not be diagnosed with head lice. As a result, the child should only be treated with a special insecticides only if there are living lice in his hair, not if he has dead lice or inactive linden eggs or if it has itching at the scalp area.

Head Lice: Prevention

Examination of the child's head at regular intervals using a comb allows the diagnosis of infestation with lice from an early age.

Early diagnosis makes treatment easier and reduces the risk of infecting other people.

In periods and areas where lice infestations occur frequently, the weekly examination of children, especially of those between 4 and 15 years of age, by parents helps to keep the infestation under control.

Clothes, towels, bedding, combs, and brushes that have come into contact with the infected person can be disinfected either by leaving them out for at least 2 weeks or by washing at 60 degrees Celsius (140 F) for 30 minutes.

Adult lice can survive for only 1 or 2 days without blood and are extremely dependent on the warmth of the human body. Home and furniture disinfection is not required.

Head Lice: Epidemiology

The number of cases of infestation with human-specific lice (pediculosis) has increased worldwide since the mid-1960s, reaching hundreds of millions annually.

Despite improvements in medical treatments and human disease prevention in the 20^th century, lice infestation continues to spread with obstinacy.

In 1997, 80% of scholars in the first years reported at least one louse epidemic in low-developed countries.

During the same period, the number of cases of lice infestation was higher than that of chickenpox.

In the United States alone, about 6 to 12 million people, most children aged between 3 and 11 years are treated annually against lice. Also, high levels of lice infestations have been reported across the world, including Israel, Denmark, Sweden, Britain, France, and Australia.

It has been shown that the number of children in a family, the sharing of beds and cupboards, the behavior of hair washing, local habits and social contacts, medical services in a certain area (eg school) and social and economic status are factors that are essential for infestation with head lice.

Girls are four times more infected than boys. Children between 4 and 14 years of age are the most affected group.

In the US, low rates of infestation are among children of African-American origin.

According to the National Health Service of the United Kingdom and many American health agencies, lice prefer pure hair because it is easier for them to attach their eggs and cling to the hair. However, this is often contested.

Infestation with head lice is more common among children aged 3 to 10 years and their families. Female sufferers are twice as affected as men, and among African Americans infestation occurs very rarely due to the texture of the hair. However, the children of these people may have lindens, and the lice can be transferred from one child to another.