Chickenpox and Smallpox Rash Comparison

Source: The U.S. Centers for Disease Control and Prevention (CDC). Differences between chickenpox and smallpox Chickenpox Smallpox How initial symptoms differ 0 to 2 days of mild illness pass before the rash develops. 2 to 3 days of severe illness pass before the rash develops. Lesions first appear on the face or trunk...