Lice (louse in singular) are small (ranging from 0.5 mm or 0.019685 in. to 8 mm or 0.3149606299216 in.) parasitic wingless insects. They cling to their host’s hair with highly adaptive claws while feeding on skin secretions and blood. Lice eggs (nits) are attached with very adhesive, water-insoluble saliva to hair shafts and very close to the skin, which makes their separation extremely difficult. Lice vary in color from pale beige to dark grey while their eggs are usually white or yellowish.
A lice infestation in human beings is scientifically referred to as pediculosis and it very rarely results in a serious disease. However, there have been documented cases where lice were blamed for typhus, relapsing fevers and trench fever. For the most part, an infestation of lice is a bothersome itchy condition that may cause embarrassment under certain circumstances, especially where it is colloquially spoken of as “cooties.”
Types of Lice
Lice have been known to plaque mankind in huge droves since time immemorial and currently, an estimated several hundred million people around the world are nagged by their infestation. In the United States alone, there are six to twelve million cases of lice infestations every year and they appear in three very distinct forms which are caused by different types of lice:
1/ Head lice (Pediculus humanus capitis) is the most frequently occurring type of lice infestation and it has been known to appear in every socioeconomic group. The female head louse lives for about thirty days and lays between seven and ten dandruff-like eggs each day of her adult life. The eggs hatch after approximately eight days to become nymphs and ten days later they become fully grown adults. If not fed, head lice die of dehydration within two days.
Head lice are not contagious in the conventional sense of the word but they are easily transmittable by direct head-to-head contact or by sharing such items as hats, pillows, towels, headphones, and hair grooming gear (combs, brushes, clips, etc.).
Symptoms – mild to severe itching in regions of the scalp, neck and behind the ears.
2/ Body Lice – An infestation of body lice (pediculus humanus corporis) is usually found among the poor populace who live in overcrowded communities with inadequate personal hygiene. Although they are slightly bigger than head lice, body lice have similar physical characteristics with the following two main differences: a) body lice do not live on their hosts but rather on the clothing (usually at the seams) or bedding and linens, and b) body lice can live up to thirty days without hydration.
Symptoms – mild to severe itching where the seams closely touch the body.
3/ Pubic Lice (pthirus pub) are also known as “crabs” and they are transmitted from one person to another by intimate or sexual contact (not from toilet seats). Similar to crabs, pubic lice are rounded and have three pairs of legs on each side of their bodies. The female pubic louse lives about three weeks and produces three eggs each day of her adult life, and the eggs take about six to eight days to hatch.
Symptoms – Severe itching to the pubic area which tends to worsen at night.
Treating Lice Infestations
Lice infestations can be easily gotten rid of with lice combs, medicated shampoos, special washes and other over-the-counter products. However, if secondary infections or allergic reactions occur as a result of the bites or excessive scratching, medical advice may be required.