Casting out devils

Salmonella are regarded as bad guys. Hardly a summer passes without severe salmonella infections via raw egg dishes or chicken that find their way into the media. But salmonella not only harm us -- in the future they may even help to defend us against cancer. The bacteria migrates into solid tumors, and makes it easier to destroy them. Furthermore, in laboratory mice they independently find their way into metastases, where they can also aid clearance.