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Typical Smallpox Vaccine Reaction

Typical skin reaction at the site of a smallpox vaccine injection

Source: U.S. Centers for Disease Control and Prevention (CDC). Available online: http://www.bt.cdc.gov

The pictures show a typical reaction to the smallpox vaccine. First, a small bump (papule) forms at the vaccine site 3 to 5 days after vaccination. This becomes a pus-filled area (pustule) a few days later. The pustule dries up and then forms a scab by about 14 days after vaccination. The scab finally falls off at about 21 days after vaccination.

Current as of: May 1, 2026

Author: WebMD Ignite Staff
Clinical Review Board
All WebMD Ignite education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: May 1, 2026

Author: WebMD Ignite Staff

Clinical Review Board
All WebMD Ignite education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.