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Lice Facts and Treatment

Friday, August 21, 2015

Invasion of the Mutant Lice! It sounds like a bad sci-fi movie but it has been this week’s medical headline.  Researchers at a meeting of the American Chemical Society in Boston reported they found lice in at least 25 states that have developed resistance to permethrin and pyrethrin, the active ingredients found in many over-the-counter remedies suggested by doctors and school nurses.   This is not the first report of its kind.  As early as the 1990s, there were reports of lice resistance.  
This latest study simply confirms that lice are developing gene mutations that may make them resistant to over-the-counter shampoos and rinses.  
It is important to note four things:  
1) This study was partially funded by a pharmaceutical company that makes prescription treatments for lice,
2) the study has not been reviewed by other scientists yet,
3) there are still treatments and
4) this was expected.  
Indeed, this is not at all unusual. Especially in areas where over-the -counter lice shampoos and rinses have been used a great deal, we can expect genetic mutations.  “When these insecticides are used a lot, the naturally resistant, probably rare, lice have a survival advantage. Just like how bacterial populations can become resistant to antibiotics, these lice take over the population,” says Richard Pollack, a public health entomologist at Harvard University.  
So what does this mean to the average parent out there?  First of all, it is important to note that these “new” lice are basically harmless.  They do not pose a significant health risk.  Dr. Bernard Cohen, a professor of pediatrics and dermatology at the Johns Hopkins Children's Center in Baltimore, states, “No serious medical conditions are transmitted by the lice.” So bottom line while head lice are a great big nuisance, they are common, still treatable, and relatively harmless.  Your child will not get sick from lice but you may get sick of treating and cleaning!
According to the Center for Disease Control and Prevention, an estimated 6 -12 million lice infestations occur each year in the United States among children 3 to 11 years of age.  If you think your child has head lice, don’t panic.  First of all, realize head lice infestation has nothing to do with poor hygiene or lack of a clean house.   Head lice infestation happens because these pesky critters are good at hopping a ride from person to person. 
Here are few ways, lice catch a ride:
  • By contact with an already infested person. Contact is common during play at school and at home (slumber parties, sports activities, at camp, on a playground). 
  • By wearing and sharing infested clothing, such as hats, scarves, coats, sports uniforms, or headbands. 
  • By using infested combs, brushes, or towels. 
  • By lying on a bed, couch, pillow, carpet, or stuffed animal that has recently been in contact with an infested person. 
These wingless parasites live on the scalp, and require human blood to survive.  They may hitch a ride on a pet, but contrary to common thought, they do not live on the family pet.  Head lice are tiny, about the size of a sesame seed.  They hatch from eggs attached (glued) to the shafts of hair about, ¼ inch up from the scalp. The eggs or nits as they are commonly referred as, take about 7 – 10 days to hatch, and at that time, the lice are colorless.  Once they start feeding, the lice become reddish-brown in color. The lice are mature in 7 – 10 days, and start laying eggs.
If you or your child has lice, the New York Statewide School Health Services Center recommends the following treatment plan:
Step 1: Treat the infested person/any infested family members
  • Consult your doctor and determine the best treatment.  Some of these treatments are not recommended for certain weights, ages, or pre-existing health conditions.  It is important to find out which treatment is best for you or your child.
  • Follow the directions exactly and thoroughly.  Pay attention to warnings such as eliminating hairdryer use.  If repeat treatment is recommended, do so. 
  • All persons with active head lice in the household should be treated at the same time.  
  • Take the time to remove nits from the hair shafts.  Special nit combs can be purchased for this purpose.  Be sure to put any nits removed into a sealed plastic bag for disposal.
  • Contact your school to find out your district’s lice/nit policy. 
Step 2: Treat the household
  • To kill lice and nits, machine wash all washable clothing and bed linens that the infested person touched during the 2 days before treatment. Use the hot water cycle (130o F) to wash clothes. Dry laundry using the hot cycle for at least 20 minutes 
  • Store all other non-washable items such as stuffed animals or large comforters in sealed plastic bag for two weeks. 
  • Soak combs and brushes for 1 hour in rubbing alcohol, Lysol, or wash with soap and hot (130o F) water.
  • Vacuum the floor and furniture.  Dispose the vacuum bag immediately or empty the vacuum container into a sealed bag and dispose of it.  Do not use fumigant sprays; they can be toxic if inhaled. 
To learn more about head lice and treatments, go to: , click on the A-Z index on the left side of the page, click on H for head lice or visit  
Lorraine Wichtowski is a community health educator at Noyes Health in Dansville.  If you have questions or suggestions for future articles she can be reached at or 585-335-4327. 

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