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.
A sample network and several stages of an outbreak. Nodes begin susceptible (small circles), become infected (large open circles), possibly infecting others along edges, and then recover (large filled circles). The outbreak finishes when no infected nodes remain.
