In 1980, Bob Gallo declared he had found a retrovirus causing cancer. It was fake!

https://www.facebook.com/profile.php?id=100089297392494 -- The Foundation for the Truth About AIDS

In 1980, three years before Robert Gallo announced the cause of AIDS had been found, he had stood up in front of the world and declared he had found a viral cause for cancer (leukemia) and had been laughed out of the room. Why? Because a group of researchers at the National Cancer Institute had found his ''retrovirus'' particles in healthy people without leukemia. It was none other than Dr. Peter Duesberg who had led Gallo into this research, who later went on to become Gallo's biggest critic. By the time of 1983 and the famous Gallo press conference with the White House, before anyone had reviewed his papers, his cancer-causing virus was not ancient history. Although now nobody remembers. Even though the viral cause for cancer was declared to be fake and not even Gallo believes it anymore, nobody seems to have gotten the memo because they still speak of retroviruses as if they are real. This is not the first time in science that something that later is roundly accepted as a fraud goes on to create new frauds and nobody gets the memo after the fact.
https://www.facebook.com/profile.php?id=100089297392494 Foundation for the Truth About AIDS