|Subspecies:||P. h. humanus|
|Pediculus humanus humanus
The body louse (Pediculus humanus humanus, sometimes called Pediculus humanus corporis) is a louse that infests humans. The condition of being infested with head lice, body lice, or pubic lice is known as pediculosis. Body lice are vectors for the transmission of the human diseases epidemic typhus, trench fever, and relapsing fever. The body louse genome sequence analysis was published in 2010.
Life cycle and morphology
Pediculus humanus humanus (the body louse) is indistinguishable in appearance from Pediculus humanus capitis (the head louse) but will interbreed only under laboratory conditions. In their natural state, they occupy different habitats and do not usually meet. In particular, body lice have evolved to attach their eggs to clothes, whereas head lice attach their eggs to the base of hairs.
The life cycle of the body louse consists of three stages: egg (also called a nit), nymph, and adult.
- Nits are louse eggs. They are generally easy to see in the seams of an infested person's clothing, particularly around the waistline, under armpits or even in body hair. They are oval and usually yellow to white in color. Body lice nits may take 1–2 weeks to hatch.
- A nymph is an immature louse that hatches from the nit (egg). A nymph looks like an adult body louse, but is smaller. Nymphs mature into adults about 9–12 days after hatching. To live, it must feed on blood.
- The adult body louse is about the size of a sesame seed (2.5–3.5 mm), has six legs, and is tan to greyish-white. Females lay eggs. To live, lice must feed on blood. If separated from their hosts, lice die.
The body louse diverged from the head louse at around 100,000 years ago, hinting at the time of the origin of clothing. Body lice were first described by Carl Linnaeus in the 10th edition of Systema Naturae. The human body louse had its genome sequenced in 2010, and at that time it had the smallest known insect genome. Other lice that infest humans are the head louse and the crab louse The claws of these three species are adapted to attachment to specific hair diameters.
- Buxton, Patrick A. (1947). "The Anatomy of Pediculus humanus". The Louse; an account of the lice which infest man, their medical importance and control (2nd ed.). London: Edward Arnold. pp. 5–23.
- Hoffman, Barbara (2012). Williams gynecology. New York: McGraw-Hill Medical. p. 90. ISBN 9780071716727.
- Bonilla, DL; Durden, LA; Eremeeva, ME; Dasch, GA. "The biology and taxonomy of head and body lice--implications for louse-borne disease prevention" (PDF). PLOS pathogens. PLOS. Retrieved 27 March 2017.
- Pittendrigh BR; et al. (2006). "Proposed sequencing of a new target genome: the human body louse, Pediculus humanus humanus". J. Med. Entom. 43 (6): 1103–1111.
- Kirkness EF, Haas BJ, et al. (2010). "Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle". Proceedings of the National Academy of Sciences. 107 (27): 12168–12173. doi:10.1073/pnas.1003379107. ISSN 0027-8424. PMC . PMID 20566863.
- "Body lice: Biology". Centers for Disease Control and Prevention. Retrieved 15 July 2016.
- Ralf Kittler; Manfred Kayser; Mark Stoneking (2003). "Molecular evolution of Pediculus humanus and the origin of clothing" (PDF). Current Biology. 13 (16): 1414–1417. doi:10.1016/S0960-9822(03)00507-4. PMID 12932325.
- Stoneking, Mark. "Erratum: Molecular evolution of Pediculus humanus and the origin of clothing". Retrieved March 24, 2008.[permanent dead link]
- "...Lice Indicates Early Clothing Use ...", Mol Biol Evol (2011) 28 (1): 29–32.