Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.
Chickenpox is a disease caused by the varicella zoster virus, also known as Human herpesvirus 3 (HHV-3), while smallpox is caused by the variola virus.
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