FRESNO, Calif. (KFSN) -- The head of the valley's Catholic Diocese has expressed ethical concerns over how he believes COVID-19 vaccines are being developed.
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As anticipation builds over the rollout of vaccines to combat COVID, Bishop Joseph Brennan of the Fresno Diocese urged valley Catholics not to jump on the vaccine bandwagon.
Brennan said, "I must tell you that there's some very serious problems with a number of the vaccines including the Pfizer vaccine that is being promoted as we speak."
Brennan said he gets his flu shots but couldn't get a shot he believed is morally unacceptable.
He explained, "I won't be able to take a vaccine, I just won't, brothers and sisters, and I encourage you not to, if it was developed with material derived from stem cells of a baby who was aborted. Or material that was cast off from artificial insemination."
Pfizer has said that is not the case with its vaccine.
Kevin McCormack of the California Stem Cell Agency in Oakland added some companies have developed synthetic proteins to make COVID vaccines.
McCormack explained, "The most impressive ones that we've seen recently, the Pfizer and the Moderna ones, those are using what's called 'messenger RNA'. So these are made from genetically tweaked proteins so they have nothing to do with embryonic tissue or fetal tissue."
McCormack said embryonic stem cells used for medical research come from in-vitro fertilization clinics. Couples will usually destroy extra eggs or donate them to scientific research. But again, he said none were used to develop COVID vaccines.
McCormack continued, "I think the bishop was wrong because embryonic stem cells were used in the development of some of these vaccines but they were mouse embryonic stem cells."
He added embryonic stem cells were currently being used in clinical trials to treat spinal cord injuries and diabetes.
The Fresno Diocese serves over a million valley Catholics.
Bishop Brennan, we're told, was out of town and unavailable to comment on our story.
Fresno's Catholic bishop expresses concerns over COVID-19 vaccines, experts say he's mistaken
Experts have explained that the vaccines by Moderna and Pfizer are made from proteins that do not come from embryonic or fetal tissues.
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