In the Soviet Union, western antibiotics couldn't make it past the Iron Curtain. So Eastern Bloc doctors figured out how to use viruses to kill infectious bacteria. Now, with antibiotic-resistant bugs vexing doctors, that eerie yet effective method might come our way. In post-antibiotic world, infection cures you!
The technique actually dates back thousands of years, in a very rudimentary form: people observed that the water from certain rivers could cure infectious diseases like leprosy and cholera. In the early 20th century, scientists figured out that these waters contained very specific types of viruses, which killed the bacteria that caused the infections. No bacteria, no infection.
You already know this from high school biology (of course), but a virus works by injecting its DNA into a living cell, hijacking the cell's replication machinery to make more viruses. When the cell can't hold all those replicated viruses any more, it explodes, releasing the baby viruses to continue the cycle again—and of course, killing the cell.
Bacteriophages are a type of virus that targets, you guessed it, bacterial cells. Starting in the 1920s, scientists in both the U.S. and Georgia (the country, not the Peach State) began purifying bacteriophages and using them to treat bacterial infections. But right around WWII, western medicine latched on to the miraculous power of antibiotics, leaving the Soviet Union to perfect what's now called "phage therapy."