THE LOUSE - also called the Body Louse - Pediculus Humanus, one of the most common sucking lice, found wherever human beings live. There are two sub-species of the common human louse: Pediculus Humanus Capitis, the Head Louse, and P. Humanus Humanus, the body louse, or cootie. The body louse is an important carrier of epidemic typhus; other louse-borne human diseases are trench fever and relapsing fever.

Smaller and much tougher than the body louse, the head louse attaches itself to the hair or scalp by means of claws on its legs, that grab around the shaft. Young lice are sometimes called red backs because of their blood-red color after feeding; they are called black backs, or gray backs, after digestion has taken place. Head lice are sensitive to heat and cold; they pass from host to host by direct contact. 

Whilst Head Lice will live on any head, the easiest way to get rid of them is to keep the hair and scalp clean and to use a fine-tooth comb frequently. In earlier times, when such hygiene was not commonly practiced, heads were shaved and wigs worn in an effort to get rid of head lice. The wigs were put into ovens to dry the lice out, this killed them.

The Body Louse is larger than the head louse and ranges in color from white to brown. It lives in the seams of clothes but is not dependent upon clothing. The species is prolific; the female lays her eggs, which hatch in about a week, in underclothes. The body louse is transferred by direct contact. It is sensitive to heat and cannot survive hot temperatures; therefore, ordinary laundry procedures will kill it.

 Head LICE 

   COOTIES    

 Pediculosis Humanus Capitis 

  What are head lice

Head Lice, or Nits, Cooties or even, Pediculus Capitis,  are tiny parasitic insects deftly adapted to live and survive on human heads and is one of our most formidable pests. They reside mainly on the scalp of their human host; found most commonly behind the ears and near the neckline at the back of the neck. Their six notable legs have evolved to firmly grasp thin hair shafts, and this provides a striking example of biological propensity, that is, evolving to suit one's environment. 

Particular to only humans, desiccated head lice have been found in prehistoric mummies. Pediculosis Capitis, commonly known as Head Lice or just Cooties, occur worldwide, and historically date back to the time of the ancient Greeks. Aristotle, even mentioned them in his writings, but they probably have lineage going back over 500 million years.

	The classic picture of the Head Louse. This is what you are looking for, crawling on your child's head.
This is a Pubic Hair Louse - Please note the difference.

Head lice are an equal-opportunity parasite; they do not worry about socio-economic class, they will make their home on any head. The fact that they prefer clean heads is disputable, but their existence does not indicate a lack of hygiene or sanitation practiced by the family of their host. There are easily 10 million cases of head lice in the USA alone. 

Head lice are mainly caught by close head-to-head contact with a person who is already carrying the insect. But may quite often, especially in families, be transferred by sharing combs, brushes, hats and other things associated with hair. The Head Louse, can also remain on bedding, especially the pillow, or upholstered furniture for around 24 - 36 hours, where it might be picked up. Neither able to fly or jump, the head louse is unlikely to wander far from their preferred habitat. Lice and their eggs are unable to burrow into the scalp.

The Nits or eggs are clued to the base of the hair shaft, and are hard to remove. After treatment the egg might be dead, but it will often remain stuck to the hair shaft and grow along with the hair.

In the West, children are more regularly infested than adults, but this is because children play together in closer quarters, touching heads etc. Caucasians more frequently come under the effect of this parasite, than any other ethnic group. The head lice prefers straight hair shafts, and they are harder to see in hair that is fair.

Bacteria  - Microscopic single-celled organisms found wherever life is possible. Generally 0.0001–0.005 mm long, they may be spherical (coccus), rodlike (bacillus), or spiral-shaped (spirillum) and often occur in chains or clusters of cells. True bacteria have a rigid cell wall, which may be surrounded by a slimy capsule, and they often have long whip-like flagella for locomotion and short hair-like pili used in a form of sexual reproduction. A few bacteria can use simple chemical substances, including carbon dioxide from the atmosphere, to manufacture their own nutrients, but most require a source of carbon derived from living organisms (i.e. organic carbon) plus other nutrients for growth. Some bacteria can reproduce every 15 minutes, leading to rapid population growth.

The most important role of bacteria is in decomposing dead plant and animal tissues and releasing their constituents to the soil (see carbon cycle). Nitrogen-fixing bacteria in the soil or sea convert atmospheric nitrogen gas to nitrites and nitrates, which can then be used by plants (see nitrogen cycle). Cheese making and fermentation reactions depend on bacteria. Bacteria also play an important part in animal digestion, especially in ruminants. However, certain (pathogenic) species may cause disease while others, such as Salmonella, can cause food poisoning.

All or most six-legged insects have a Four-Stage Life-Cycle. Eggs ; Larvae; Pupae and the Imago - the adult.  The Head Louse lives for about a month.

Lice are sometimes referred to as cooties, the eggs as nits, and infested people as being  lousy. Sometimes, being infested quite badly, can make us feel lethargic, hence the expression, . . .  I am feeling lousy.

Head lice infestation can be psychologically disturbing, and also be quite scary to a young child, and adult alike. Even the scratching can be psychologically produced; a teacher might start scratching for no reason just because some of her students are infected. However, head lice are not a health hazard, and generally not responsible for the spread of any diseases.

The infestation by head or other body lice is termed as pediculiasis and chemical treatments or insecticides, directed against lice are formally called pediculicides. Those that kill the adult imago, and nymphet-lice are sometimes called less formally, lousicides. Those that kill the developing embryo within the egg are ovicides, and this is the most common attack, breaking the life-cycle. 

Head lice derive nutrient by blood-feeding once or up to fives times each day, and cannot survive for more than 24 - 36 hours, without feeding on a person's blood, and must live at around room temperature. It pierces the skin, injecting irritating saliva, and sucking blood. Lice do not become engorged like Bedbugs, but their color changes to a reddish brown after feeding. Head lice hold onto the hair with hook-like claws found at the end of each of their 6 legs. Adult lice are active and can travel quickly. 

A female head-louse may deposit more than 100 eggs in a lifetime, at a rate of about six eggs each day. A young female must feed first, and of course mate. Only those eggs deposited by inseminated female lice will hatch. A nymphal louse, or larva, hatches from its egg after about 8 days of development, and begins to feed, grow and develop, until it attains the adult stage after about 9 -12 days subsequent to hatching. 

In the West due to better grooming, an infested person may have fewer than 15 effective lice on the scalp at any time, but there may be hundreds of viable, dead and or hatched eggs or nits. Egg casings are well adhered to the shaft of the hair, and generally can only be removed with a rake through with a Nit-Comb. Otherwise, they just grow out with the hair. With enough magnification, the developing nymph can be seen moving within the egg; hatched eggs though are nearly transparent.

Treatment should be only be considered when living and active lice or viable eggs, can be seen and confirmed, as the chemicals used for treatment are quite perilous to human health. A child who has been affected and treated on several occasions, may build up dangerous levels of the insecticide in their bodies, causing liver problems and other complaints.

How Does Your Body Fight Infection?

Immunity   -  The resistance of the body to infection, especially resistance due to antibodies. Babies have passive immunity from antibodies transferred from the mother’s blood through the placenta. Active immunity involves the formation of antibodies after exposure to an antigen - bacteria that invade the body during an infection are antigens. The two different kinds of immune response produced by antibodies involve: white blood cells called T-lymphocytes - produced by the thymus, which produce cells with antibody properties bound to their surface and are responsible for such reactions as graft rejection; B-lymphocytes, which produce cells that release free antibody into the blood.

Leucocyte - lymphocytes - or white blood cell. A colorless cell found in large numbers in the blood. There are several kinds, all involved in the body’s defense mechanisms. Granulocytes and monocytes destroy and feed on bacteria and other microorganisms that cause infection -  see also phagocyte. The lymphocytes are involved with the production of antibodies.

Phagocyte   -  A cell that engulfs and then digests particles from its surroundings: this process is called phagocytosis. In vertebrate animals, phagocytes are a type of white blood cell that protect the body by engulfing bacteria and other foreign particles.

Immunization is the production of immunity by an injection containing antibodies against specific diseases e.g. tetanus and diphtheria, which provides temporary passive immunity, or by vaccination, which produces the longer lasting active immunity.

Antibody   -  A protein produced by certain white blood cells  - lymphocytes that reacts with a particular foreign particle e.g. a bacterium,  that has entered the body. The antibody helps to destroy the foreign particle, known as the antigen. If the same bacteria invade the body in future, many more of the same antibodies are produced, enabling the body to destroy the bacteria very rapidly and so resist infection. This provides the basis of  immunity. Antibodies are also responsible for the rejection of foreign tissue or organ transplants. See also monoclonal antibody.

Monoclonal antibody  -  A type of pure antibody that can be produced artificially in large quantities and used, for example, to distinguish the major blood groups. Mouse lymphocytes producing the required antibody are fused with mouse cancer cells; the resulting hybrid cells multiply rapidly and all produce the same type of antibody as their parent lymphocytes.

Whilst all this bodily protection sounds wonderful, the problem with MRSA, is that there is no defence to it, no answer to its attack.

TREATMENT   No matter where you buy your treatment, on-line, at a drug store or from your doctor. Treatment is with anti-parasite medication, designed for that particular parasite.  For Head Lice,  the most effective treatments are shampoos and creams. Follow your doctors directions and the directions that will come with the appropriate chemicals, as they can be quite toxic. Even so the Head Louse is hard to kill as it grows evermore resistant to these remedies. Repeat treatment maybe necessary, so be careful.

If you are pregnant do not use any insecticide treatment as this may damage the embryo / foetus. 

Get strict medical advise before treating children.                           

Itching of the scalp or the perception that something is crawling on the head, does not always necessitate treatment for head lice. Without close scrutiny and suitable experience, it is sometimes difficult to correctly distinguish from other material caught in the hair, such as dandruff, scabs, dirt, or even other insects, like the flea.

Itching is caused by the actual bite, as the scalp is quite sensitive but also to the reaction to the enzyme / chemical compound, that these blood-sucking insects inject into the wound via their saliva.  The chemical acts as a mild anaesthetic, but more importantly as an anti-coagulant. Chemicals like, chlorophacinone, stop the body's defences from carrying out their job.

In normal circumstances when the skin is sufficiently broken, the body's blood-pressure forces blood to the surface. If the flow is not too profuse, after about two and a half minutes the blood flow will gradually stop. Blood platelets, which tend to be sticky,  hang onto the sides of the wound as a clot, and build up, hopefully stemming the bleeding. Eventually these dry and form the reddish scab, that all children know well.      Anti-coagulants stop the blood from clotting, and therefore stopping the wound being sealed,  thus giving a good flow of nutrient to the parasite, and also facilitating digestion.

 

The Head Louse and the Pubic Louse, whilst obviously related they are NOT the same creature.

At least 90% of all Westerners have contracted or been affected by the Head Louse at one time or another. Most blood-sucking insects are or prefer to be host-specific. This means that the rat-flea prefers to feed off the rat, but will feed off other mammals if their specific host is not available. Pediculus Capitis, the head louse, will prefer to feed off the human animal, but will feed off another mammal, given that this is all that is available.  Lice, of today, have grown and evolved along side mammals and birds, and no doubt fed on dinosaurs, making their ancestry much longer than ours.

TREATMENT

Look around for recommended safe products, preferably NON-TOXIC. Ask your parents what home remedies they used on you. Ask friends and family, what experiences they have had. Ask the school what they would use.  Google Inc offers several ADS on this site, hand-picked to help you learn more.

If the problem gets too bad, your MD may be needed to help.

Remember. 

Don't Panic !!!!

There is no shame in catching any parasite, but they all tend to populate quickly so prevention, or quick action, is better than the cure.

    © Roy G Symonds BA [Law] 2009