Validity of self-assessment of skin reaction after smallpox vaccination.

Objective: Smallpox vaccinees should be evaluated for the presence of a major skin reaction ("take") one week after vaccination, but this could prove to be logistically infeasible in the context of an emergency mass-vaccination campaign. We validated a tool for self-evaluation of the vaccination site for presence of take.

Methods: We conducted a prospective, double-blinded, paired-measurement validation study of 174 non-naive adult vaccinees and their physician evaluators.