ECTOPARASITES

Ectoparasites live on the outer surface of the body. Most ectoparasites are arthropods (insects or arachnids).

Lice

small wingless insects which suck blood
cling to body covering - feathers in birds, hair in mammals, clothes in humans. Their feet are adapted to fit what they have to cling to

eg. Head lice have small claws and can only hold onto head hair.
Pubic lice have much larger claws to hold onto the thicker pubic and armpit hair

Fleas

small wingless jumping insects which live on the body as adults, sucking blood.

Mites

tiny arachnids - smaller relatives of ticks
Scabies is caused by mites burrowing into the skin
Demodex is a normally harmless mite which lives in the hair follicle of the eyelash - may lead to styes

Some ectoparasites, like other biting arthropods may also transmit other diseases

   eg.   Body Lice - transmit Typhus (bacterial disease which causes a fatal fever)
            Fleas - thought to have transmitted the Bubonic
            Plague from rats to humans

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