What are head lice?
Head lice are tiny wingless parasites that feed off human blood. Lice develop in three stages, nit to nymph to full-grown louse. The average size of a grown louse is 2-3mm, about the size of a sesame seed. Adult lice and nymphs (baby lice) are grayish white or tan in color. They are capable of changing color to camouflage in the hair. After a feeding, a louse’s abdomen fills with blood, giving them a brownish tinge in color. Nits (lice eggs) appear as tiny brown, tan, yellow or white tear-drops firmly attached to the hair shaft. The term nit refers to a louse egg, which may or may not contain a viable embryo. Nits appear darker if an embryo is within. An empty leftover shell will appear clear.
Who gets head lice?
Reports estimate that 10-12 million individuals are treated for head lice annually. Most cases are common, although not limited to, amongst school-aged children. Anyone who comes into head-to-head contact with an individual who already has a lice infestation is at risk. Personal hygiene and cleanliness in the home or school has nothing to do with getting lice. Head lice actually prefer clean hair.
What is the life cycle of head lice?
A mature head louse can lay 6-10 nits daily and up to 180 lice eggs throughout its lifespan, which is approximately 30 days long. Nits are generally laid within 1 cm of the scalp, as they need warmth to develop and hatch. A louse glues each egg to the hair shaft. The glue serves as a protective shell for the developing embryo. It takes approximately one week for a nit to develop into a nymph and an additional week for a nymph to develop into an mature adult louse and start the reproduction cycle all over again.
What are the symptoms of head lice?
Most people associate head lice with an itchy scalp. Contrary to most beliefs, head lice often produce no symptoms at all. Itching is actually caused by an allergic reaction to the parasites saliva. Roughly 50% of people will develop an itchy scalp. In many cases, individuals develop a rash behind the ears and at the nape of the neck.
How do head lice spread?
Head lice do not jump, hop, or fly – they crawl. Lice are spread mostly through direct head to head contact. It is possible, although unlikely, that head lice may spread through sharing hair accessories such as hairbrushes and hair clips, hats, scarves, pillows, blankets and other items, which had direct contact with the infested person.
How long can a louse survive without a human host?
It is possible for a healthy adult louse to live up to 2 days without a feeding. However, in most cases, lice will not live off of the head for longer then 12 hours.
Can my pet get head lice?
Dogs, cats, and other pets do not spread head lice. Just like humans can’t get fleas.. pets cannot get head lice as they only feed on human blood.
How long can a person have a case of head lice before realizing it?
It is possible to have head lice for years without knowing it, especially for those individuals that don’t experience itching. Generally, by the time head lice are discovered, the individual has had them for 2 to 6 weeks.
Are head lice dangerous to ones health?
Head lice are not known to spread disease. According to the Harvard School of Public Health, the greatest harm to children and adults associated with lice “results from the well-intentioned, but misguided use of toxic substances to eliminate head lice.”. However, secondary infections have been known to occur after scratching the scalp rigorously and introducing bacteria to damaged skin.
Can head lice go away on their own?
No, head lice cannot go away without corrective action. If left alone, head lice will continue to multiply and eventually infest your entire family.
Who should be checked if a case of head lice is discovered?
All close contacts should be checked so that re-infestation does not occur. This includes parents, siblings, babysitters, close family and friends. Close contacts are likely to have lice, especially if the infestation is severe. It is highly recommended that if a case of lice is discovered, all family members receive a thorough comb-out. Oftentimes another family member can have just a few nits or one louse, which can be easily missed without a comb-out. If left untreated, a full-blown infestation is likely to occur within a couple of weeks.
What is the quickest and most reliable method to get rid of head lice?
There are no shortcuts to ridding one of lice. Manual removal with a fine-tooth nit comb is the most effective method of eradicating head lice. This process is very tedious and time consuming, but must be done in order to guarantee complete lice removal.