"It's incredible, and a big surprise, that the same infection that caused so much devastation can help create a cancer-fighting cell," said Dr. Ankit Bharat, chief of thoracic surgery and director of the Canning Thoracic Institute.

So, researchers at Northwestern started their journey to figure out why this might be happening. They discovered when someone gets badly infected with COVID, the virus can actually enter the bloodstream, shedding its RNA. That gets circulated and becomes a very common immune cell called monocytes.

New research from Northwestern Medicine shows that in some cases of severe COVID, the immune response actually killed cancer cells. Researchers are trying to harness that immune power into new cancer therapies.