Bedbugs, lice, fleas and mites are blood-sucking ectoparasites whose bites cause allergic skin reactions. Diagnosis of bites is based on the morphology of the skin eruptions and the pattern of involved skin areas. Confirmation of the diagnosis often requires detection of the causal parasite. The main reservoir for ectoparasites (e.g., bedbugs, fleas, lice and scabies mites) are humans, but animals are also known to harbor ectoparasites (e.g., certain fleas and mites). Fleas, body lice and certain mite larvae in the tropics can transmit infectious diseases, but bedbugs, headlice, pubic lice and scabies mites cannot. Therapy is primarily directed against itching and bacterial superinfections. Pediculosis and scabies are additionally treated with t0pical insecticides. In order to kill freshly hatched larvae, topical treatmentmust be repeated after one week. In the case of pediculosis, people who have come into contact with symptomatic individuals also need to be treated, whereas with scabies, all contact persons must undergo treatment in order toprevent further transmission. Topicalinsecticides, in combination with anti-itch treatment, is usually sufficientto immediately relieve the symptoms and promote permanent healing of the skin lesions.