Pope Francis approved a note released by the Congregation for the Doctrine of Faith on Monday, condoning the use of coronavirus vaccines that have an indirect connection to abortion, saying it is "morally acceptable" to receive the vaccine.

"It is morally acceptable to receive Covid-19 vaccines that have used cell lines from aborted fetuses in their research and production process," the CDF wrote. "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."

The letter was signed by Cardinal Luis Ladaria Ferrer, the Vatican prefect, and Archbishop Giacomo Morandi, Vatican secretary. Pope Francis approved the text on Dec. 17 and released the note Monday.

The Pfizer-BioNTech and Moderna vaccines were involved in a commonly employed "confirmatory test" that relies on HEK293, a cell line derived from a human embryonic kidney cell from a fetus that was aborted in the 1970s. Because of this, some Catholics have expressed concerns about the ethics of getting the vaccine, with some calling for Catholics to "reject a vaccine which has been produced immorally."

The papal notice follows a similar missive from bishops in the United States who sanctioned getting the vaccine despite concerns from members of the Catholic community. One Texas church leader, Bishop Joseph Strickland, said that he "urge[d] all who believe in the sanctity of life to reject a vaccine which has been produced immorally."

"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, despite their remote connection to morally compromised cell lines," the committees wrote, referring to the use of HEK293-derived tests. "Being vaccinated safely against COVID-19 should be considered an act of love of our neighbor and part of our moral responsibility for the common good."

The CDF's note continues a trend in previous pronouncements, according to Vatican News. As recently as 2017, the Holy See said the value of vaccines and their distance from contemporary abortion practices "lead us to exclude that there is a morally relevant cooperation between those who use these vaccines today and the practice of voluntary abortion."

"The morality of vaccination depends not only on the duty to protect one's own health, but also on the duty to pursue the common good," the CDF said. "In the absence of other means to stop or even prevent the epidemic, the common good may recommend vaccination, especially to protect the weakest and most exposed."