Stryper singer Michael Sweet says he regrets receiving COVID-19 vaccinations, which he says were required for the band to perform at some venues during the pandemic. He has speculated about a possible connection to his retinal detachment and thyroid cancer, while acknowledging that he cannot prove the vaccines caused either condition; the article notes that there is no credible evidence supporting such a link.

Sweet says his retina detached after his first vaccination and that he was diagnosed with papillary thyroid cancer several years later. He had surgery to remove part of his thyroid in December 2023 and had his third eye operation in August 2022 after a retinal-detachment diagnosis in November 2021; papillary thyroid cancer accounts for about 80% of thyroid cancers and generally has a favourable prognosis when treated early.