But looking back, every five or so years dating back to the 1800s, there have been reports in the medical literature of patients with terminal cancer coming down with a mild flu-like illness and miraculously recovering from their cancer. Sometime during the 1960s, somebody said, "Oh wait, what causes mild flu-like symptoms? Flu or flu-like organisms, which are viruses." And so people started looking around for various naturally occurring viruses that might cause cancers to regress. That's where the whole field was born—and since then, there's been this sequence of almost accidental discoveries leading to different viruses being tested to treat cancers.

How does this oncology therapy distinguish itself from other viruses used on the market today?

A lot of the viruses that are being worked on today are genetically engineered to target the cell and crank out a drug that will kill it. But in our case, we don't need a drug—this reovirus just does it all by itself. This is targeted therapy handed to you by Mother Nature.

Reovirus is an acronym for respiratory enteric orphan virus. Reovirus is, if not the most common environmental virus, one of the most common. It is found naturally in sewage and water supplies. But if you have ever walked through wet soil, you might have exposed yourself to it. By age 21, anywhere between 70 and 100 percent of the adult population will have been infected with a reovirus sometime in their life.

It infects the lining of the lungs and the bowels of all mammals. But it doesn't cause disease. The time it takes for the virus to kill those cells is the same time those cells are programmed to die anyway. The lining of your lungs sloughs regularly because it's constantly assaulted by oxygen, and so it's programmed to die and you get new cells. Your bowels are programmed to die because they're exposed to every nasty toxin that your body's trying to get rid of that doesn't go out in your urine. They slough off in the same way.

If the reovirus is that common, why have so few people heard of it?

Who studies a virus that doesn't cause a disease? The ones we've studied are the ones that are important to us medically, which until now have been negative. But actually, most viruses don't cause disease. Viruses that kill people are the environmental anomalies, not the other way around.

How does Reolysin work as a cancer tretment?

The reovirus needs the RAS pathway to be turned on to replicate. And turned on RAS pathways are most commonly found in cancer cells. In fact, about two-thirds of all cancers have an activated RAS pathway. It's a very common target. If you look at the aggressive cancers, pancreatic cancer is virtually 100 percent RAS-activated. Brain cancers, melanomas, the skin cancers—almost all metastatic disease—are all between 90 and 100 percent RAS-activated.

If the reovirus goes into a cell where the RAS pathway isn't activated, nothing happens. The cells have natural antiviral pathways and the virus just gets chewed up by the cell enzymes. If the virus goes into a cell that has a RAS-activated pathway, that's an enabling condition for it to grow. Every cell that it infects will break open when it dies, and infect the tissue around it and produce anywhere between 5,000 and 40,000 progeny virus particles. Those will replicate, and it'll kill the tumor within three days.

After the virus invades, the immune system also helps kill tumors. It's a one-two punch.

How accepted is the idea of ingesting a virus?

I'm a microbiologist, so I know virology really well. That part of it didn't bother me, which as it turns out, is the part that bothered most people. Infecting a sick or dying person with a virus, no matter how benign, has been the question with this drug.