Overview of Fleas, Ticks & Mites

Fleas, ticks, and mites are ectoparasites, parasites that live on or burrow into their hosts' skin. Parasites live at least part of their life cycles at the expense of host organisms. They can cause blood loss, skin irritation, allergies, and disease.

Some parasites live continuously on a single host, and others live intermittently on their host. Many parasites spend as little as 10 percent of their life actually feeding (i.e., living) on a host. Some live on different host species at different stages of their life cycle—for example, ticks that carry Lyme disease live on white-footed mice as larvae, and on deer or other mammals as adults. Some can live on various host species, and others are restricted to a specific host species, often to a single area of the host's body. For example, demodectic mange is caused by a hair follicle mite and is usually found only on the head or legs.

Hosts provide a number of essential resources for parasites, such as:

  • Food (sweat, blood, tears)
  • A warm, moist, protected environment
  • Transportation and transmission to another host (some parasites' life cycles require several hosts)

Publication Review By: the Editorial Staff at HealthCommunities.com

Published: 01 Aug 2001

Last Modified: 15 Dec 2014