The Vatican says that it's "morally acceptable" to receive a vaccination for COVID-19, even if the vaccine's research or production involved using cell lines derived from aborted fetuses, given the "grave danger" of the pandemic.

The Congregation for the Doctrine of the Faith, the Vatican office charged with promoting and defending church morals and traditions, said in a document released Monday that "when ethically irreproachable Covid-19 vaccines are not available ... it is morally acceptable to receive Covid-19 vaccines that have used cell lines from aborted fetuses in their research and production process."

Pope Francis approved the text on Thursday, Vatican News reported.

The statement said that "all vaccinations recognized as clinically safe and effective can be used in good conscience with the certain knowledge that the use of such vaccines does not constitute formal cooperation with the abortion from which the cells used in production of the vaccines derive. It should be emphasized, however, that the morally licit use of these types of vaccines, in the particular conditions that make it so, does not in itself constitute a legitimation, even indirect, of the practice of abortion, and necessarily assumes the opposition to this practice by those who make use of these vaccines."

The U.S. Conference of Catholic Bishops released its own statement last week, which said: "In view of the gravity of the current pandemic and the lack of availability of alternative vaccines, the reasons to accept the new COVID-19 vaccines from Pfizer and Moderna are sufficiently serious to justify their use," as it deemed these vaccines' connection to abortion "very remote."

The U.S. conference said that receiving one of the vaccines "ought to be understood as an act of charity toward the other members of our community" and "considered an act of love of our neighbor and part of our moral responsibility for the common good."

NPR reached out to Pfizer, Moderna and AstraZeneca for comment but did not receive a reply by time of publication. The Vatican statement did not cite by name any COVID-19 vaccines now in use or development.

Cells derived from elective abortions have been used in the manufacture of vaccines since the 1960s, Science magazine reported, "including current vaccines against rubella, chickenpox, hepatitis A, and shingles. They have also been used to make approved drugs against diseases including hemophilia, rheumatoid arthritis, and cystic fibrosis."

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