EDMONTON, Alberta — When a vaccine is available to treat or prevent COVID-19, it is OK to take it.

That’s the message from the bishops of Alberta and the Northwest Territories in a pastoral letter to the faithful as they navigate for Catholics a path through a moral dilemma presented by COVID-19 vaccine development. It echoes messages from the Vatican and bishops’ conferences in the U.S. and Britain.

While many of the possible vaccines are synthetic and have no relationship to abortion in their production, several contenders were developed using cell lines descended from cells originally derived from aborted fetuses or embryonic stem cells.

Even if a vaccine is sourced from cell lines distantly derived from aborted human fetuses, which is an evil act according to Catholic teaching, the bishops say taking that vaccine is morally permissible given the remoteness of the recipient from the original act of abortion, the scarcity of ethical alternatives, and the grave threat that COVID-19 poses to public health.

While physicians and families should seek out ethical vaccines, the bishops say that use of previous cell lines is so prevalent in research that there may not be an ethical alternative accessible during the current COVID-19 pandemic.

“Making use of abortion to create cell lines for research and development is an affront to human dignity and cannot be morally justified,” the bishops write. “Sadly, such cell lines are so widely used in the biopharmaceutical industry that a vaccine that has not been ethically compromised in its production and/or testing by their use may very well not be available for employment against COVID-19.

“With respect to someone simply receiving the vaccine, the degree of connection with the original evil act is so remote that, when there also exists a proportionately grave reason for vaccination, such as the current, urgent need to halt the COVID-19 pandemic, then the church assures us that it is morally permissible for Catholics to receive it for the good of personal and public health.”

The bishops’ letter is in keeping with statements from the Pontifical Academy for Life, which studies issues of biomedicine and law. The academy has addressed this issue in statements in 2005 and 2017.

The chairmen of the U.S. bishops’ doctrine and pro-life committees issued a similar statement Nov. 23, adding: “Some are asserting that if a vaccine is connected in any way with tainted cell lines, then it is immoral to be vaccinated with them. This is an inaccurate portrayal of Catholic moral teaching.”

On Dec. 2, the Pfizer & BioNTech vaccine was approved for use in the United Kingdom. A statement from the Catholic Bishops’ Conference of England and Wales said: “Each of us has a duty to protect others from infection with its danger of serious illness, and for some, death. A vaccine is the most effective way to achieve this unless one decides to self-isolate.”

It, too, gave similar background on development of the vaccine and said: “Catholics may in good conscience receive any of these vaccines for the good of others and themselves. In good conscience, one may refuse a particular vaccine but continues to have a duty to protect others from infection.”

Dr. Moira McQueen, executive director of the Canadian Catholic Bioethics Institute, who was part of a group advising the bishops on the vaccine letter, told Grandin Media in the Archdiocese of Edmonton: “The official teaching is saying then, if ethical (synthetic) vaccines are truly not available, then take this vaccine. … The level of moral cooperation by people in 2020 is what the church would call ‘remote.’”

“Here we are talking about a pandemic. The idea is because of two factors — lack of personal responsibility for an original action yet facing serious illness and needing to protect yourselves and your children — church teaching says, and I think it’s reasonable, that in these circumstances taking any vaccine is justified. They won’t say the action is right in the fullest sense, but they do say it’s justified. If an ethical vaccine comes along, you have to choose to use that one.”

McQueen was part a group of Catholic medical, legal and theological experts who wrote to Prime Minister Justin Trudeau early in the pandemic, pressing for any vaccine to be ethically sourced.

The Moderna and Pfizer vaccines are both Messenger RNA vaccines in which molecules are chemically synthesized. However, the Oxford and AstraZeneca vaccines are sourced from cell lines that were originally abortion-derived, according to the Lozier Institute, a pro-life institute based in the U.S., which studied a range of vaccines under development.

Dr. David Evans, professor of medical microbiology at the University of Alberta, is quick to note that the vaccines are sourced differently and the bishops’ letter shouldn’t be used as justification to refuse to be immunized. Evans, who was a part of an advisory group to the bishops, leads a team that has studied the coronavirus extensively.

Still, McQueen expects some Catholics and others to refuse a vaccine as a matter of conscience.

“It may seem acceptable to some people not to take the vaccine and say they will stay at home and never leave. But I don’t see how people could reasonably take a stance like that and then go out into society, as they must at some point and perhaps they are carriers,” she said. “There’s very much the reality of an individual conscience decision, which should always be respected. But that person always has to be thinking too about her or his responsibility to everybody else.”

Catholic teaching on the common good is also a factor in making a good conscience decision, McQueen said.

Evans noted that any government-approved vaccine will be safe and effective; however, it’s not yet known how long the immunity will last. Patients may have to be inoculated again with a “booster” after weeks or months.

Ehrkamp is editor of Grandin Media, based in Edmonton, Alberta.