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Medical Term:


Pronunciation: smawl'poks


An acute eruptive contagious disease caused by a poxvirus (Orthopoxvirus, a member of the family Poxviridae) and marked at the onset by chills, high fever, backache, and headache. In 2–5 days these constitutional symptoms subside and an eruption appears as papules, which become umbilicated vesicles, develop into pustules, dry, and form scabs that, on falling off, leave a permanent marking of the skin (pock marks). The average incubation period is 8–14 days. As a result of increasingly aggressive vaccination programs carried out over a period of about 200 years, smallpox is now extinct.

Synonym(s): variola major, variola

[E. small pocks, or pustules]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.