Pediculosis Pubis, which is commonly known as “Crabs” or “Crab Lice” is an infestation of the pubic hair by Phthirus pubis, the crab louse. The lice, which resemble crabs, are a millimeter in length, feed off human blood and multiply rapidly. They use their claws to hold onto the public hair and this is where the female louse lays her eggs. The eggs can hatch anywhere from 5 to 10 days into nits, or baby lice. The nits develop into full grown lice in the same amount of time, 5 to 10 days.

A louse cannot live without blood for more than 24 hours; with blood they can survive for up to 6 weeks. Crabs are not deadly and do not damage the health of their hosts – the person they are infecting. However, Crabs are extremely irritable and the symptoms that come with having crabs are very bothersome.

Crabs can be transmitted from person to person by oral, anal or vaginal intercourse. Anywhere an infected person’s pubic hair comes into contact with another’s, chances are the Crabs will spread. During oral sex, Crabs can be transferred to one’s eyelashes, eyebrows, face, chest hair, or scalp. In addition, bed linens, towels and clothing are susceptible to infestation. It has been reported that the spreading of Crabs can be a result of poor hygiene.

Symptoms of Pediculosis Pubis

Symptoms of Crabs can show up one week after exposure or for up to four weeks after exposure.

The most indicative sign of Crabs is itching in the pubic hair area. While this does not occur all of the time, most people that have an infestation experience itching symptoms. The lice inject saliva into their host when feeding. This is the cause of most of the itching that occurs.

The nits or lice can be spotted on a person, or a person may be able to spot them on his or her partner. The louse is silver or black in color and the nit is oval-shaped and very shiny. They are usually attached to the base of the hair shaft. Sometimes the areas where the Crabs bite the skin are visible as tiny blue sores, or maculae ceruleae.

It is common to notice the lice while bathing, especially if you use white towels to dry off with as some of the insects can get rubbed off onto the surface of the towels.

Diagnosing Pediculosis Pubis

Diagnosing Crabs is quite easy. Once the patient is aware of the itching, the doctor can examine the patient to confirm the existence of the insects. Lice and nits can also be viewed under a microscope to make sure they do in fact exist.

Treatment for Pediculosis Pubis

A variety of medicated lotions, topical creams and powerful shampoos can be prescribed to eliminate the Crabs. Permethrin cream rinse is used and applied all over the infested area: the pubic hair, under and inside the fold of the buttocks, and the entire groin area.

The scalp can be treated with Lindane shampoo. It is a 10-minute leave-in shampoo that kills the lice. However, Lindane is slightly controversial because of its many side effects that include: neurological damage, cancer, poisoning, and environmental contamination.

Infestations of the eyelashes can be treated with a petrolatum ointment. Sometimes doctors do not use this ointment on children, and instead pluck the insects out one by one. Pregnant women are not advised to use the ointment, and are recommended to use Rid, a medicine that kills all forms of lice, including common head lice, and their eggs.

A metal comb with very specific bristles can be used to filter out lice from the hair manually. This method is recommended by the National Pediculosis Association. Some other non-traditional home remedies that have been used are mayonnaise and tea tree oil.

Because the lice can survive on bed linens, towels and clothing, all of these items should be washed in very hot water. If this is unable to be done, wrapping blankets and other clothing items in plastic bags and storing them away can rid the lice. Without blood, the Crabs cannot live for more than 24 hours.

Everyone who has been treated for Pediculosis should have a follow-up about a week later to make sure that the Crabs have been eliminated. Otherwise, a re-infestation can occur.

What Happens if Pediculosis Pubis Goes Untreated?

Pediculosis poses no real health threat. If untreated, the lice can move to other parts of your body, making itching worse and even unbearable. It can damage the quality of life and makes the person who is infested with them suffer from relentless itching and sleepless nights.

If diagnosed with Crabs, the best option is to get the lice treated right away. They can become extremely bothersome as they multiply rather quickly.

Preventing Pediculosis Pubis

Abstaining from sexual intercourse is the best way to prevent an infestation of Crabs or transmitting the lice to someone else. Sexual intercourse is not 100 percent safe even with condoms as the lice live on the pubic hair. During intercourse, the lice can reach areas on the pubic hair that is not protected by a condom and transmission can easily occur.

Getting tested for sexually transmitted diseases (STDs) can prevent the spread of Crabs or prevent any unnecessary irritation by Crabs.

If you have Crabs, all sexual partners must be notified immediately in order to get them tested and, if needed, treated right away.

Who Is at Risk for Contracting Pediculosis Pubis?

The following includes those people that are at a higher risk of contracting Pediculosis Pubis:

  • Anyone engaging in sexual intercourse, protected or not
  • People with new sexual partners
  • People with more than 2 partners
  • People not using any method of protection
  • Individuals abusing drugs or alcohol before engaging in sexual intercourse
  • Living or having sexual relations with someone who is infested
  • Sharing bed linens, towels, and/or clothing with someone who is infested
  • People lacking a good hygiene routine

Individuals who are not getting tested on a regular basis for STDs and other infections/infestations

Statistics about Pediculosis Pubis

The following are some important statistics about Pediculosis Pubis:

  • Over 3 million new cases of Pediculosis Pubis occur every year
  • Approximately 1 in 90 people get Crabs each year
  • Nits stay alive for up to 14 days after removed from the host
  • A female louse lays about 40 nit eggs at a time

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