<virology> A common highly infectious and contagious childhood viral infection that results in a generalised blistery red rash.

The name was meant to distinguish this weak form of the pox from smallpox (chicken being used, as in chickenhearted, to mean weak or timid).

Starts as an eruption of red papules (bumps) which become vesicles (blisters) than pustules. Other symptoms include malaise, weakness, sore throat, cough and fever. Incubation period is 14 to 17 days. There can be complications of chickenpox including pneumonia and encephalitis, particularly in adults but also sometimes in children, and reactivation of the same herpes virus is reponsible for shingles (zoster).

Synonyms: varicella

(18 Dec 1998)