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.
Schematic representation of the sequence of events that occurred each time symptoms consistent with influenza developed in a health care worker during the pandemic (H1N1) 2009 outbreak, Hospital das Clínicas, São Paulo, Brazil, May–October, 2009.
