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.
Specific symptoms per (a) virus and (b) age group. Here infection events (not positivity counts) are analysed. A viral event is considered positive for upper respiratory, lower respiratory or systemic symptoms if the individual reported at least one of the characterizing symptoms during the 7 days surrounding the test date.
