An official website of the United States government
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
LockA locked padlock
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Image Number K11077-1
E. coli, magnified about 7,000x.
Photo by Eric Erbe, Colorization by Christopher Pooley.
640 pixels wide: (k11077-1.jpg)