Fig. 2.
Mass screening in the Attaouia Sector, Province of El Kelaa Sraghnas, Morocco, September 1979 Data collection for screening was not effective until 1980.
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.