New mathematical model predicts more virulent microbes

Microbes and humans interact in myriad ways, sharing a long history. Many of the most successful microbes are those that inhabit but do not kill their host. Cheaters lose. Tuberculosis settles into the lungs. Helicobacter pylori, the microbe causing ulcers, burrows into the stomach where it thrives on acids. And Salmonella typhi takes up residence in the gallbladder. All of these organisms can persist in our bodies for decades. What explains their success?