Guest : Prof Marc Mendelson | Head Of Infectious Diseases at University of Cape Town |

Imagine you develop an infection -- anything from a typical urinary tract infection to

tuberculosis. Now imagine there's nothing doctors can do.

The discovery of antibiotics changed medicine in the 20th century. Today, they're

widely used to treat infections caused by bacteria. More than 150 million prescriptions

are written for antibiotics in the U.S. each year. But bacteria are starting to adapt to the

drugs and are becoming harder to kill. That's called antibiotic resistance.