"A million Americans have died. Close to 10 million worldwide have died because of this. I know the conspiracy idiots are telling you that it's not true - it is. So I got vaccinated twice, then had a booster, and I'm about to get another boost."
The 72-year-old singer has accepted it is going to be a "fact of life" getting a Covid vaccine every year.
He told iHollywoodTV: "This is gonna be a fact of life. Every year I go and get my flu vaccine — I get the shots.
"Because even though flu might not be life-threatening, I don't wanna deal with the headaches and stuff."
Last October, Simmons admitted he "felt nothing" when he had Covid-19, noting that he and his KISS bandmate Paul Stanley both had the virus, but he admits their experiences were markedly different.
He said: "Paul and I had completely different experiences. His [symptoms] were pretty mild. I felt nothing. I didn't know I had Covid.
"Out of respect for everyone, I quarantined, but my appetite was up, my energy was strong, no running nose, no nothing."