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.
An increase in redness represents a stronger migratory signal. Red asterisk indicates significant major sources of viral migration. Viral migration patterns were inferred using the Slatkin-Maddison approach on 100 iteration of random subsets of equal number of sequences per location (see Methods for details).
