An official website of the United States government
Here's how you know
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.
Neighbour-joining tree of Clostridium difficile RT231 isolates circulating in Sweden between 2006 and 2015. Samples are colour coded according to year of isolation: 2006 (blue), 2007 (green), 2008 (red) and 2009 to 2015 (black).