Wellcome Image of the Month: Busting Bugs
The 31st of January is the first of three National Bug Busting Days this year, followed by 15 June and 31 October. Bug Busting days aim to increase awareness, detection and treatment of head lice and nits to reduce their spread in the community.
This scanning electron micrograph was created by Garry Hunter with David Randall at the School of Biological Sciences, University of Sussex, and forms part of his Small World series of work. It shows a head louse (coloured yellow) clinging onto three strands of human hair (coloured red). Adult head lice can be up to 4 mm in length which is roughly equivalent to the size of a sesame seed. To prepare the sample for imaging, the head louse was first pickled in various strengths of alcohol solution to prevent the exoskeleton from collapsing. It was then dried, sprayed with a fine gold dust, and imaged under vacuum by firing electrons through the sample at the required depth. This image received a 2005 Wellcome Image Award of Excellence.
Head lice or Pediculus humanus capitis are insects which live in close proximity to the human scalp and feed on human blood. They lay eggs (nits) which are white or yellow in colour and firmly attach to the hair shaft near the scalp. They do not have wings nor can they jump. Instead they are most commonly spread by close head to head contact. They are not known to spread disease. Head lice bites and secretions on the scalp can cause itchiness, and treatment is either with chemicals (to kill the lice) or using physical methods (to remove the lice) such as repeated combing with a fine-toothed comb.
Founded in 1988, Community Hygiene Concern is a not-for-profit charity that raises awareness of common parasites found in the UK.
References and Further Information
Image credit: Garry Hunter, Wellcome Images
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