Without germs, we're nothing

by Nikki Tundel, Minnesota Public Radio

Sure, bacteria can make us sick. But they also make us who we are. And we couldn't live without them.

St. Paul, Minn. — Bacteria outnumber us a trillion to one. So it's a good thing most of them are friendly.

Gerald Callahan, the author of Infection: The Uninvited Universe, talks about why we need bacteria to survive.