Fig. 1.
Household-wise distribution of primary cases and household contacts (co-primary cases, non-susceptible contacts, secondary cases, and uninfected susceptible contacts).
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.