If you were interested in proving the poster wrong, you could have just mentioned that HPV is linked to certain cancers. It's true and commonly known. If they doubted it, they can check for themselves.

Instead you posted AI spam that we're going to completely ignore.

The funny part is you and it are still completely wrong. Gizortnik said that cancers aren't viruses. You said "cancers are related to virii." You changed the claim to give an answer, that wasn't even your own, that didn't refute anything he said.

ALSO "virii" is not not the plural of virus. Even in Latin, it wouldn't be virii.

Here, in case this helps you:

Copilot:

What is the plural of virus
The plural of "virus" is "viruses." Some people wonder if it should be "viri" or "virii," but those forms aren't correct in English.
"Viruses" is the standard and widely accepted plural form.

Is cancer a virus
Cancer itself is not a virus, but certain viruses can increase the risk of developing cancer.

If you actually wanted to contradict him, you'd want to focus on prophalactic vs. therapeutic vaccines, because vaccines aren't specifically preventative and aren't specifically for viruses.