Transmission Potential of the Human Head Louse Pediculus Capitis (Anoplura: Pediculidae)

Title: Transmission Potential of the Human Head Louse, Pediculus Capitis (Anoplura: Pediculidae).
Authors: Takano-Lee, Miwa1,2,3*
Edman, John D.1,2,3*
Mullens, Bradley A.1,2,3*
Clark, John M.1,2,3*
Source: International Journal of Dermatology; Oct2005, Vol. 44 Issue 10, p811-816, 6p
Document Type: Article
Subject Terms: · BLOOD substitutes
· LICE as carriers of disease
· PARASITES — Life cycles
Abstract: BACKGROUND: Millions of people are infested by head lice every year. However, louse transfer between hosts is not well-understood. Our goals were to determine: (1) which stages were most likely to disperse and why, (2) the likelihood of fomites transmission, and (3) if host blood gender affects louse development.

METHODS: Various life stages of lice at differing densities were permitted to cross over a 15-cm hair bridge placed between two artificial blood-feeding arenas. Louse transfer caused by hot air movements, combing, toweling, and passive transfer to fabric was investigated. The ability of lice to oviposit on different foreign substrates and the hatching potential of eggs intermittently incubated for 8h/night on a host were likewise investigated. Louse in vitro development following feeding on human female or male donor blood was compared.

RESULTS: Adult lice were the most likely to disperse. Neither population density nor hunger significantly affected dispersal tendencies. Lice were dislodged by air movement, combs and towels, and passively transferred to fabric within 5min. Females oviposited on a variety of substrates and 59% of eggs incubated for 8h/night hatched after 1416days. There was no survivorship difference between lice artificially fed on female vs. male blood.

CONCLUSION: Adult lice are the most mobile, indicating that they are most likely to initiate new infestations. Although head-to-head contact may be the primary route of transmission, less direct routes involving fomites may play a role and need further evaluation. Blood-borne factors do not appear to cause any gender-biased host preference. [ABSTRACT FROM AUTHOR]

Author Affiliations: 1Center for Vector-borne Diseases, University of California, Davis, CA.
2Department of Entomology, University of California, Riverside, CA.
3Department of Veterinary and Animal Science, University of Massachusetts, Amherst, MA.
Database: Academic Search Premier

*The author(s) cited above are not in any way affiliated with Rainforest Essentials. Their citation is offered solely for informational purposes and not to be construed as an endorsement of Lice Off!™ in particular or any of our products in general.