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How to Avoid Catching Head Lice

What Am I Looking For?

Even if there are no known outbreaks of lice that you are aware of, it's still a good idea to watch for signs of head lice on a weekly basis. No one is immune to getting infested with these mites. Make sure to check all family members for lice and nits (lice eggs). But what are you looking for exactly?
 
Lice are reddish-brown wingless insects. They do not jump or fly, but can crawl rather quickly. Nits are always oval-shaped and are grayish-white. They will be found glued at an angle to the side of the hair shaft.
 
It may be easy to confuse nits with white specks of dandruff or other hair debris. However, dandruff can be dusted off the hair shaft easily, while nits will be securely fastened to the hair shaft. In some cases, clumps of dandruff may stick to the hair shaft. They may look like a nit. However, these clumps may be irregularly shaped or elongated segments that are encircling the hair shaft. The way to tell the difference between hair debris and nits is that the hair debris will be dislodged easily; the nits are always an oval shape and are not easily dislodged.
 

Understanding the Characteristics of Lice

Understanding how lice live and spread is the first step in knowing what to look for. Head lice, or Pediculus humanus capitis, are parasitic insects. They can be found on the head, eyebrows, and eyelashes of humans (animals, such as dogs and cats, will not aid in the spread of head lice). They feed on human blood several times a day and live close to the scalp.
 
Head lice have three forms, which include:
 
  • The egg (also called a nit), which takes about eight to nine days to hatch.
     
  • The nymph, which is the immature louse that hatches from the nit. It matures into an adult about 9 to 12 days after hatching.
     
  • The adult, which is about the size of a sesame seed. It has six legs and is tan to grayish-white in color. It can live about 30 days on a person's head, but dies within 1 or 2 days if it falls off the head. The females can lay about six eggs each day.
 
The surest way to determine if anyone in your family has lice is to find a live louse on the scalp or hair. Lice are quite small, move quickly, and avoid light, making them challenging to find. Using a magnifying glass and a fine-toothed comb can help in the search.
 
Even if you do not find any live lice, you may discover nits. These are usually found strongly attached within a quarter-inch of the base of a hair shaft. If no live lice are found but nits are firmly attached within a quarter-inch of the base of a hair shaft, it is likely that the person is infected and should be treated.
 
However, if nits are found attached more than a quarter-inch from the base of the hair shaft, it is most likely that they are dead or already hatched. If there are no live lice and the only nits found are more than a quarter-inch from the scalp, the infestation is probably old and no treatment is likely needed.
 
A Dose of Reassurance for Parents of Picky Eaters

About Head Lice

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