Full text
PDFPage 2590
. 1990 Aug;56(8):2590. doi: 10.1128/aem.56.8.2590-2590.1990
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.