Scabies: an epidemiologic reassessment.

Scabies is a highly contagious parasitic infestation whose exact nature is unknown. A reassessment of epidemiologic data questions accepted ideas such as that scabies is a sexually transmitted disease; 30-year cycles of scabies epidemics exist; changes in the immune status of the host population (herd immunity) are epidemiologically significant; fomite transmission is rare; and blacks are resistant to the mite. Scabies epidemics are due to several factors and improved surveillance is needed before the disease can be better controlled.