Meet Your Bacteria: The Hidden Communities that Live in Your Gut and Other Organs

We are a society obsessed with cleanliness — but is this a healthy obsession? Do we use antibacterial products correctly? Should my child wash her hands after playing in the park? Why does my doctor insist that I finish the bottle of antibiotics even though I feel better? What is Lactobacillus? And superbugs?

The human body plays host to trillions of bugs — living microorganisms too tiny to see — in...