Microbiologists at Duke University have harnessed the polio virus and programmed it to attack cancer — just one of many efforts to turn harmful viruses and bacteria into disease-fighting warriors.

"All our tests indicate that we may have something at hand that may be effective in patients," said Dr. Matthias Gromeier.

Scientists genetically altered the polio virus before unleashing it in mice with life-threatening, cancerous brain tumors. The virus destroyed cancer cells, but left healthy cells intact.

"That polio virus had lost its ability to grow in healthy neurons in the brain, yet it still replicated in brain cancer cells and destroyed these cells within 5 to 7 hours after infection," said Gromeier.

The tumors completely melted away in just days, spurring hopes that the same technique could be effective in treating human cancers. In fact, researchers are looking to begin human trials in as little as 18 months.

"It's like shooting with a rifle instead of a shotgun," said Dr. Darell Bigner, associate director at the Duke Comprehensive Cancer Center.

"The new treatments are going to be more specific, they're going to be less toxic, and we believe they're going to be more effective," he said.

Brain cancer patient Jeanne Novak is the ninth person in a clinical trial that pumps a protein from a pneumonia-causing bacteria directly into her brain.

Scientists found that, like the polio virus, the genetically altered pneumonia protein only kills cancer cells, and was extremely effective in animal studies.

"A large number of the animals could actually be completely cured of their tumors by these same sort of infusions," said Duke researcher Dr. John Sampson.

Novak feels lucky to be a part of the human trial, and hopes its findings will help effect even more promising treatments.

"Cancer breakthroughs right now are just astonishing and I feel like I'm right on the edge on a lot of that," she said.