Doctors have known about oncolytic viruses since the mid-1800s (since before they even really knew what a virus was), when they started reporting that tumors sometimes went into remission for a while following a bout of natural viral infection.
Sometimes it was infection with the measles, or the flu, and in at least one case, the chicken pox caused temporary regression of lymphatic leukemia.
In the 1950s and ’60s, the ability to propagate viruses in the lab instead of only in living organisms, made it possible for researchers to begin exploring the potential of oncolytic viruses to cure cancer.
Polio,herpes, measles, and mumps are among the so-called oncolytic viruses, which preferentially infect and kill cancer cells.
Although the medical community has known about oncolytic viruses for over a century, it’s only now that their power is being harnessed for viable cancer treatments.