"The HEK293 cell line was used in the design, development, and production stages of that vaccine, as well as for confirmatory testing," said Rhoades and Naumann. The two compared the AstraZeneca vaccine to the current rubella vaccine, which also was reliant on "morally compromised cell lines."
In the case of the rubella (German measles) vaccine, explained the bishops, the risk posed to an unborn child and the community at large by the illness outweigh the morality concerns related to the development of the vaccine.
"In such a situation, parents are justified in having their children vaccinated against rubella, not only to avoid the effects of rubella on their children, but, secondarily and just as importantly, to prevent their children from becoming carriers of rubella, as the spread of rubella can lead to the infection of vulnerable pregnant women, thereby endangering their lives and the lives of their unborn children," said the bishops.
Rhoades and Naumann acknowledged that while Catholics should avoid the AstraZeneca vaccine in preference for one of the other two, it may not be possible for someone to do this without putting society at risk from the coronavirus. If this were to happen, a Catholic would be permitted to receive that vaccine.
"It may turn out, however, that one does not really have a choice of vaccine, at least, not without a lengthy delay in immunization that may have serious consequences for one's health and the health of others," said the bishops.
"In such a case, just as accepting a vaccination for rubella with a morally compromised vaccine is morally permissible because of the lack of alternatives and the serious risk to the public health, so it would be permissible to accept the AstraZeneca vaccine," they said.
A person who refuses to be vaccinated, said the bishops, has "a moral responsibility to undertake all the precautions necessary to ensure that one does not become a carrier of the disease to others, precautions which may include some form of self-isolation."
While the vaccines for coronavirus are permissible to receive despite their moral flaws, it is imperative that Catholics "must be on guard so that the new COVID-19 vaccines do not desensitize us or weaken our determination to oppose the evil of abortion itself and the subsequent use of fetal cells in research," they said.
"For our part, we bishops and all Catholics and men and women of good will must continue to do what we can to ensure the development, production, and distribution of a COVID-19 vaccine without any connection to abortion," said the bishops.