PUBIC LICE


PUBIC LICE (CRABS)

History

The most common parasites that infect humans are lice (Pediculosis pubis or pubic lice) and mites (Scabies). Pediculosis pubis, commonly named ‘crab lice’ or ‘crabs’ occurs worldwide and dates back to the writings of the ancient Greek philosopher, Aristotle.

Pubic lice(Phthirus pubis, or the crab louse) infests areas of the body where hair grows, especially the groin, and are most common in adolescents and young adults. It has been of epidemic proportions across all age and socio-economic class groups since the 1960s.

An estimated 3 million people with new cases of the infestation are treated each year in the United States.

The most common areas affected are:

  • abdomen
  • anus
  • groin

Cycle

  • An adult louse gets onto the skin and lays eggs
  • Eggs hatch 6-10 days later releasing baby lice, called nymphs
  • They attach their eggs, called nits, to the host’s pubic hair
  • Within 15 days these grow into adults and multiply again
  • Nymphs and adult lice feed on human blood

Other Facts

  • A louse lives for about 6 weeks but dies within 24 hours without a blood meal
  • Female lice lay 2-3 eggs daily which are fastened to shafts of body hair which hatch into nits within a week
  • The lice attach to hair, appear as tiny white/gray specks, are highly mobile and can crawl several inches in a day

Symptoms

  • Feeling run down
  • Inflamed skin and small red or bluish irritations caused by ‘crab’ lice bites and defecation
  • Intense itchiness at the infected area, usually more intense at night (begins about 5 days after infestation)
  • Irritability
  • Mild fever

Public lice can also infect:

  • eyebrows
  • eyelashes
  • hair
  • underarm hair

Transmission

These parasites are transmitted by:

  • an infected parent to children through close contact
  • intimate contact
  • sexual contact

Contact with contaminated items, such as:

  • bedding
  • clothing
  • toilet seats
  • towels
  • upholstered furniture

Persons engaging in oral sex can be infected in the hair of the:

  • chest
  • eyebrows
  • eyelashes
  • face
  • scalp

Risk Factors

  • Avoid close contact with others if you have scabies or pubic lice
  • Some people do not itch so do not know they are infested

Diagnosis

Diagnosis is made with the naked eye, a magnifying glass, or under a microscope, from observation of the shape of the louse and/or eggs.

Pubic lice:

  • look like tiny pale gray crabs
  • darken in color when swollen with blood
  • display six legs, four of which are crab-like claws used to grasp the hair of the host

If you think you have been exposed to pubic lice or scabies see your doctor or health practitioner immediately to determine whether or not treatment is required.

Treatment

Treatmentis with anti-parasite medication, the most effective treatments being shampoos and creams containing Lindane, Permethrin or a related compound.

Procedure

  • Always follow directions carefully as these chemicals are quite toxic
  • The infestation may be stubborn, and you may need to repeat the treatment if symptoms continue or recur

Note

  • Decontamination of all bedding and clothing with hot-water machine washing or dry cleaning is essential to avoid re-infection
  • Everyone exposed to pubic lice should be treated at the same time
  • The home should be thoroughly vacuumed
  • Quilts or blankets can be stored away from other clothing and bedding for a month as, without blood, the lice and any nits that hatch will die during this time

Caution

  • Pregnant and breastfeeding women are advised not to use this drug and to use a product safe for these conditions, such as Rid, a liquid pediculicide, which kills both lice and eggs.
  • Recommendations for use in infants and small children should be followed carefully

Other Treatments

  • Bathe or shower before treatment
  • An application of 1% gamma benzene hexachloride ointment or lotion is left on for 12 hours

Natural Treatments

Scalp Infestations

  • Lindane shampoo left on for 10 minutes
  • Rinse thoroughly

Eyelash Infestations

  • White petroleum jelly ointment for 10 days
  • Nits and parasites in the lashes of children can be carefully pulled out by tweezers

Prevention

Risk Factors

  • Condom use does not prevent crab infection because infected pubic hair and skin comes into contact with other pubic hair and skin
  • Contact with infected individuals
  • Multiple intimate sexual contacts

Help Factors

  • Dry-clean or wash materials that may carry scabies or pubic lice in very hot water (125 degrees Fahrenheit)
  • Know your partner’s sexual history
  • Pubic lice and eggs can survive for 1-2 weeks in bedding or clothing so it is important to thoroughly clean anything that may be infested

Preventive Treatment

Anyone an infested person has come into close contact with should be treated to ensure that the lice have been eliminated, including:

  • close friends
  • family
  • sex partners

Follow-up Procedure

  • Abstain from sexual contact for 48 hours after treatment
  • A follow-up examination is recommended after one week to determine if any live nits remain
  • Anyone you have had close contact with or who has shared your bed linen, clothes, or towels should be treated, even if they do not have an itch or rash
  • Household members should be treated if symptoms emerge

Prognosis

  • Lice have been known to spread diseases such as typhus.

Because the skin has been irritated and needs time to heal itching may persist even after the lice have been eradicated. Temporary relief may be obtained by using a soothing lotion, such as: