Is Pubic Lice A Virus Or Bacteria?

by | Sep 5, 2022 | Blog, Sexual Health, sexually transmitted, STD, Traveling

Pubic Lice is a sexually transmitted disease and have become considerably rare now. In the past, two popular outbreaks of pubic lice were in the Israeli army between 1972 and 1999. However, the cases of pubic lice may still be more in regions of the world with a greater number of reported STDs; they still remain low in the United States. (1) This article explores whether pubic lice are viral or bacterial in nature, their transmission, diagnosis, and ways to eliminate them from the body.

pubic lice crabs


What are Pubic Lice?

It is a small insect resembling a crab. The adult pubic lice may range in size from 1.1 mm to 1.8 mm. It is different from the lice found on the head and body and is also known as a pubic crab. The pubic lice live on the skin and the thick hair near the pubic region and suck the individual’s blood – essentially making it a parasite.


Transmission of Pubic Lice

Pubic lice are most commonly found on the pubic hair and occasionally on the eyelashes and body hair found on other parts. The transmission of pubic lice occurs during sexual contact and is often observed along with numerous other sexually transmitted diseases. (2) (3) The diagnosis of pubic lice occurs through the identification of an adult’s lice on the pubic hair, along with the presence of its eggs on the hair shafts.


Is Pubic Lice Associated with a Bacterial Infection?

Pubic lice, also referred to as crabs, are often associated with a bacteria known as Acinetobacter baumannii. This opportunistic pathogen is becoming a public health threat, particularly in individuals admitted to the hospital. (4) Once the individual starts itching the area affected by the lice, it promotes a secondary bacterial infection. The bacterial infection worsens the symptoms and leads to conditions like impetigo and pyoderma.


Symptoms Of Pubic Lice

Individuals with pubic lice commonly present with constant irritation and intense itching in their pubic region. This is because of the presence of immune-mediated hypersensitivity reaction on the skin around their pubic area. After the first exposure to the pubic lice, it may take the individual up to 3 to 6 weeks to develop the symptoms. However, the symptoms of reexposure to pubic lice start much sooner. Individuals may report itching only 2 to 3 days after being re-exposed. These lice have the ability to transfer infections like relapsing fever, trench fever, and typhus from one individual to another – which is why it is important to refer to a doctor and get it treated as soon as possible. (5)


Diagnosis of Pubic Lice

For accurate pubic lice diagnosis, a thorough physical evaluation by the health professional is crucial. They may use a bright light or a magnifying glass to identify live adult lice to confirm the diagnosis. A lice comb can help identify a current infection. Only nits during the examination can’t confirm the diagnosis – it is important to find a live lice. In addition, a false diagnosis may occur in individuals with dandruff, dirt particles, or hair spray remnants on their pubic hair.


Treatment Options for Pubic Lice

In the past, the lice present on any part of the body were either removed by hand or, if that was not possible, shaving that area helped get rid of the lice. Later, the use of the lice comb became the most popular method for removing lice; however, it was still unable to remove the smaller-sized lice and the nits laid by the lice. Wet combing refers to the removal of lice using lice comb from moist hair. (6)

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Drug Therapy for Pubic Lice

Another approach that has become common in recent years for the removal of lice from various parts of the body is pharmacological treatment. This method of lice removal works on two principles:


  • Causing paralysis of the lice by inducing neurotoxicity
  • Suffocating the louse by using topical creams and ointments


While these methods are very effective for removing lice, they are not as effective for removing their eggs. Hence, topical pharmacological therapy may need to help with the complete eradication of the lice. The topical treatments for this purpose include malathion, lindane, and pyrethroids. (7)


On the other hand, if an individual may not want to opt for a topical treatment, they may opt for oral therapy for pediculosis. The oral drug most commonly given today for removing lice from the body includes Ivermectin. While Ivermectin is very effective at this, it has a risk of neurotoxicity in those consuming it for more extended periods. This is why, while it has demonstrated clinical effectiveness in a number of studies published over the past few years – it is not yet FDA approved. Hence, Ivermectin is typically considered a second-line treatment for pubic lice that are resistant to topical treatments.


The Bottom Line

Pubic lice infestation, also referred to as pediculosis, can be a great source of discomfort and concern for the individual affected by them and their partner. These resemble the appearance of a crab and are also referred to as pubic crabs. Having pubic lice can demonstrate symptoms like itchiness and redness, and scratching the area may put one at risk for bacterial infections. The pubic lice diagnosis is only made after visually detecting live adult lice on the pubic hair, after which a number may treat it of methods. The methods that are commonly used today include the use of topical creams, which help suffocate and paralyze the lice, after which they can be easily removed.





  1. Mimouni, D., Grotto, I., Haviv, J., Gdalevich, M., Huerta, M., & Shpilberg, O. (2001). Secular trends in the epidemiology of pediculosis capitis and pubis among Israeli soldiers: a 27-year follow-up. International journal of dermatology, 40(10), 637–639.
  2. Flinders, D. C., & De Schweinitz, P. (2004). Pediculosis and scabies. American family physician, 69(2), 341–348.
  3. Pierzchalski, J. L., Bretl, D. A., & Matson, S. C. (2002). Phthirus pubis as a predictor for chlamydia infections in adolescents. Sexually transmitted diseases, 29(6), 331–334.
  4. Perez, S., Innes, G. K., Walters, M. S., Mehr, J., Arias, J., Greeley, R., & Chew, D. (2020). Increase in Hospital-Acquired Carbapenem-Resistant Acinetobacter baumannii Infection and Colonization in an Acute Care Hospital During a Surge in COVID-19 Admissions – New Jersey, February-July 2020. MMWR. Morbidity and mortality weekly report, 69(48), 1827–1831.
  5. Powers, J., & Badri, T. (2022). Pediculosis Corporis. In StatPearls. StatPearls Publishing.
  6. Packer, H., & Heiberger, A. L. (2016). Getting Ahead of Head Lice: Treatment in the Setting of Resistance. South Dakota medicine : the journal of the South Dakota State Medical Association, 69(10), 468–470.
  7. Salavastru, C. M., Chosidow, O., Janier, M., & Tiplica, G. S. (2017). European guideline for the management of pediculosis pubis. Journal of the European Academy of Dermatology and Venereology : JEADV, 31(9), 1425–1428.

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