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.

"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.

Is it possible something good can come from a Covid infection? Chicago area medical experts think so. A new study led by researchers at the Northwestern Medicine Canning Thoracic Institute and published in the Journal of Clinical Investigation has revealed a connection between COVID-19 infection and cancer regression.