Natural insensitivity and the effects of concentration on the repellency and survival of American dog ticks (Dermacentor variabilis) by DEET.

N,N-Diethyl-m-toluamide (DEET) is by far the most used repellent worldwide. When applied topically to the skin, the active ingredient has been shown to provide protection from a variety of hematophagous insects, including mosquitoes and flies. DEET's effectiveness against ticks is influenced by a variety of factors (e.

Rearing density and susceptibility of Rana pipiens metamorphs to cercariae of a digenetic trematode.

Cercariae of many digenean trematodes target particular developmental stages of their hosts. For some digeneans that are parasites of amphibians, infection appears timed to host metamorphosis. The success and timing of metamorphosis is itself affected by a number of factors, including host density.