"The war against bacteria is not something that can be won by humans," Sulakvelidze says. "If you try to wipe them out, they will always return. Only they will be stronger."
If the problem is classic Darwinian adaptation, the solution might lie in the very same process. Thus, Sulakvelidze, Morris, and others have turned their attention to bacteriophages, which have evolved over eons to destroy bacteria. This approach to fighting infection lets nature do the lab work usually carried out at tremendous expense, and with high failure rates, by the pharmaceutical industry. In contrast to engineered drugs, phages are as numerous and varied as the bacteria they attack. What's more, they evolve along with their prey, matching bacterial adaptation step by step.