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Executive Summary

The utilization of abortion-derived cell lines in COVID-19 vaccines raises important ethical questions. The NCBC recognizes ethical distinctions among available COVID-19 vaccines based on their utilization of abortion-derived cell lines when all other considerations are equal. Vaccines that do not use abortion-derived cell lines in any phase of design, manufacture, or testing are the best ethical choice if they are reasonably available, safe, and effective. Vaccines that utilize abortion-derived cell lines in a more limited manner, such as for confirmatory testing, are preferable to those that utilize abortion-derived cell lines in more than one phase of development and, in particular, in the manufacturing process. For grave reasons, people could decide in good conscience to accept vaccines that utilize abortion-derived cell lines to protect their own lives and health and that of others in the absence of any satisfactory alternative. Being vaccinated can be an act of charity that serves the common good. An ethically problematic vaccine, however, should be accepted only “under protest.” A person who decides to take such a vaccine should make known his or her opposition to abortion and to the use of abortion-derived cell lines in vaccines. People may also legitimately decline to use a vaccine with some connection to abortion. The Catholic Church neither requires nor forbids the use of ethically problematic vaccines, but instead urges people to form their consciences and to carefully discern the moral and prudential issues involved.

Over the past year, unprecedented progress has been made to create safe and effective vaccines to mitigate the COVID-19 pandemic. The National Catholic Bioethics Center (NCBC) provides these points to consider to help Catholics and others respond to ethical questions raised by COVID-19 vaccines, in particular by the use of abortion-derived cell lines in someCOVID-19 vaccines.

Abortion, Ethics, and COVID-19 Vaccines: Sorting Out the Issues

Background: The Connection between Some Vaccines and Abortion

For over two hundred years, and in particular since the 1950s, vaccines have helped millions of people avoid the toll of sickness and death from diseases ranging from polio, measles, and chickenpox to Ebola. However, these scientific achievements came under scrutiny in the 1990s as evidence emerged that a number of childhood vaccines were being manufactured using human diploid cell lines obtained from elective abortions (abortion-derived cell lines).[1] As people became aware of this connection, many began to ask if their use of these vaccines would be unethical, since it appeared to involve them in the efforts of others to perform and to benefit from abortions.

Traditionally, moral theologians have assessed ethical questions about involvement in the wrongdoing of others in terms of the principle of cooperation. It has been widely recognized as unethical behavior for someone (a cooperator) to intend or affirm the goal of a person performing a morally evil action (a principal agent) or to become closely involved in the principal agent’s action by providing specific assistance that the principal agent needs to perform a morally evil action. What has been judged to be morally tolerable, at least in the short-term if there are legitimate goods that someone needs to obtain, are acts that do not involve sharing an immoral goal or intent and that do not involve close or essential involvement in immoral actions being performed by others. Debate about the ethics of accepting vaccines produced by utilizing abortion-derived cell lines has taken place for years in these terms.

The teaching authority of the Church rarely intervenes in cases involving cooperation because the issues can be complex and detailed. Nevertheless, given the importance of this issue, the Church has issued authoritative and advisory guidance on four occasions since 2005, including a Note from the Congregation for the Doctrine of the Faith (CDF) on December 21, 2020.This guidance, read in the context of other important teachings of the Church, provides a resource that people can employ to avoid moral evil and to witness to the gospel of life.

Guidance from the Church

Dignitas personae (2008), an Instruction from the CDF, contains the most authoritative magisterial teaching on this topic. The CDF first notes a key consideration beyond the immorality of abortion itself, namely that the bodies of human embryos and fetuses must be treated with respect after death and not exploited as mere biological material. Next, Dignitas personae points out the duty for scientists to remove themselves from areas of research and development using abortion-derived cell lines even if they were themselves not involved in any abortions or in obtaining human tissue. Finally, the CDF addresses people who need medicines already developed with the use of these cell lines of illicit origin. Dignitas personae notes that, given these serious needs, “danger to the health of children could permit parents to use a vaccine which was developed using cell lines of illicit origin, while keeping in mind that everyone has the duty to make known their disagreement and to ask that their healthcare system make other types of vaccines available.”[2]

In 2017 the Pontifical Academy for Life (PAV), an advisory body to the Holy See, issued a joint statement with two Italian organizations. This statement highlighted the urgent need for people to accept vaccines to protect the health of others who would benefit from herd immunity. The PAV further argued that clinically recommended vaccinations could be used with a clear conscience because the use of vaccines does not entail morally relevant cooperation with voluntary abortion.

In 2005 the Pontifical Academy for Life issued advisory guidance in the form of Moral Reflections at the request of the CDF.[3] The substance of these reflections was confirmed in a 2007 letter from the prefect of the CDF to the president of the United States Conference of Catholic Bishops. The PAV noted that end users of vaccines, such as doctors and parents, were only remotely and passively involved in relation to voluntary abortions. However, public authorities, health systems, and those involved in marketing and distributing vaccines derived from aborted fetal cell lines were more intensively involved and hence more responsible. The PAV also described a grave responsibility to advocate for and to use alternative vaccines to end this unethical situation as soon as possible. Moreover, the PAV recognized that it could be right, under certain conditions, to refuse to use such vaccines.

On December 21, 2020, the CDF issued a Note on the use of vaccines for COVID-19 which reaffirms the guidance just outlined above. In addition, the CDF clarifies three important points: (1) the decision to accept a vaccine must be voluntary; (2) if people refuse a vaccine, they should take great care to avoid transmitting COVID-19 to protect the vulnerable and to serve the common good; and (3) there is a moral imperative for governments, pharmaceutical companies, and organizations to help make COVID-19 vaccines available to poor countries.

Taken together, this guidance makes clear that it was wrong for those responsible to create abortion-derived cell lines. Nevertheless, serious reasons may permit people to use vaccines produced with abortion-derived cell lines to protect their own lives and health and those of others if no effective alternative vaccines are available. Beyond stating what is and what is not morally permissible, this guidance outlines additional duties to advocate for and to use alternatives whenever possible and also recognizes that, in some cases, people may decide in good conscience to forgo any vaccines connected with the use of abortion-derived cell lines.

COVID-19 Vaccines and Aborted Fetal Cell Lines

Hundreds of vaccines for COVID-19 are in development. While there is a great variety among these vaccines, for the purposes of this statement, they can be divided into three groups based on a resource produced by the Charlotte Lozier Institute:[4]

Those that do not use abortion-derived cell lines in any phase of design, manufacture, or testing; Those that do not use abortion-derived cell lines in the manufacturing process but used an aborted fetal cell line at one point in development, such as confirmatory testing (e.g., Pfizer–BioNTech); and Those that use abortion-derived cell lines in more than one phase of development and, in particular, the manufacturing process.[5]

NCBC Assessment

People must carefully discern in conscience whether or when to be immunized against COVID-19 and which vaccine to accept. Based on the moral principles, Church guidance, and facts outlined above, the NCBC holds that none of the vaccines currently in development or use is excluded or forbidden in principle. However, the NCBC holds there are significant differences among vaccines based on their connection with abortion-derived cell lines when all other considerations are equal. Those vaccines in group 1 are the best ethical choice because they do not rely on abortion-derived cell lines in any phase of design, manufacture, or confirmatory testing. Vaccines in group 2 are preferable to those in group 3, using the logic of choosing the lesser evil, because the former are less reliant on abortion-derived cell lines in key respects. Finally, people could discern in conscience, for grave reasons and in the absence of satisfactory alternatives, to use the vaccines in group 3 to protect their own lives and health and that of others.

In the United States as of the date of this statement, there are no vaccines currently or imminently available that fall into group 1. COVID-19 vaccines from Moderna and Pfizer-BioNTech fall into group 2. The Janssen (Johnson & Johnson) vaccine falls into group 3. Of note, the abortion-derived cell line Janssen uses in its manufacturing process, PER.C6, was created in 1995, decades after other abortion-derived cell lines, and has been promoted for use in biotech products based on its human derivation.

Those who use a vaccine linked to abortion-derived cell lines should do so only “under protest” and have a duty to make known their opposition to abortion and to the use of abortion-derived cell lines. Beyond the issue of these cell lines, there are other important factors to consider in making a decision—which may justify choosing a vaccine with a greater connection to abortion-derived cell lines in certain cases. These factors include:

First and foremost, our belief that “Life and physical health are precious gifts entrusted to us by God [and that] we must take reasonable care of them, taking into account the needs of others and the common good” (Catechism of the Catholic Church, #2288).

•The significance of the U.S. Food & Drug Administration’s (FDA) current Emergency Use Authorizations (EUAs) for vaccines in use.[6] For example, someone might judge that an EUA, while legal, does not provide for him or her sufficient evidence of long-term safety and so postpone accepting a vaccine until standard FDA approval is granted.

•Relevant information in the FDA’s fact sheets on each vaccine.[7]

•One’s own health needs and underlying conditions, such as certain allergies. For example, the Janssen (Johnson & Johnson) vaccine does not include polyethylene glycol, a substance used in the Pfizer and Moderna vaccines that can cause severe allergic reactions in some people. On the other hand, the Janssen (Johnson & Johnson) vaccine utilizes polysorbate 80, which makes it contraindicated for those with polysorbate allergies, and this is not in the Pfizer or Moderna vaccines.

•General and personalized guidance about the disease and the vaccines from reliable and trusted health care professionals.

•The influence of external pressures either to vaccinate or to refuse vaccination must not take away the voluntary character of this decision. The Church and the NCBC hold that it is unacceptable to put pressure or to mandate that a person violate a well-formed judgment of conscience.

•One’s responsibility for the health of others, and other circumstances related to family and community life or line of work, including one’s ability or willingness to take appropriate precautions to limit transmission in the absence of immunization.

•Issues of safety, efficacy, and reasonable availability among the vaccine options.

Beyond these essential conclusions, however, there is more to address and to do.

Beyond Moral Minimums: Witnessing to the Gospel of Life

The duties and exigencies of Christians regarding the use of vaccines and other therapeutics produced with abortion-derived cell lines cannot be addressed by the principle of cooperation alone. Christians are called in a particular way to witness to the Gospel of life. Beyond our duty to avoid moral evil, we are called to protect and promote moral goods. As Pope St. John Paul II noted in Evangelium vitae, “Enlightened by this Gospel of life, we feel a need to proclaim it and to bear witness to it in all its marvelous newness. . . . [This includes] the affirmation of the inseparable connection between the person, his life, and his bodiliness . . . [and] the presentation of human life as a life of relationship, a gift of God, the fruit and sign of his love.”[8]

Regarding the ethically significant issue of using the bodies of humans killed in elective abortions to promote biotech research and development, Christians must “go to the very roots of life and love” to renew our witness to the sanctity of human life and our determination to end the use of abortion-derived cell lines.[9]

The effort needed to successfully demand safe and effective alternatives to abortion-derived cell lines will require courageous and dedicated witness for three reasons. First, pharmaceutical companies and researchers have come to rely on these lines. Change will require strong pressure to justify the investment of time and resources that will be needed to replace problematic cell lines with ethical ones. Second, the evil practice of benefitting from abortion is older and more extensive than many people realize. Some people mistakenly think that only a few abortions in the 1960s and 1970s were necessary to produce the aborted fetal cell lines now in common use (such as WI-38, MRC-5, and HEK-293). However, physicians began to exploit the practice of abortion to advance research as early as the 1930s.[10] And scores of abortions were necessary before abortion-derived cell lines could be successfully produced.[11] Third, scientists, doctors, politicians, and advocates increasingly have cited the benefits of using abortion-derived cell lines in vaccine production to justify even more unethical biotech research and development. For example, in 2001 a group of Nobel laureate scientists appealed to the public acceptance of producing vaccines with aborted fetal cell lines in urging President George W. Bush to provide federal funding for human embryonic stem cell research. In 2009, scientists cited this same precedent to justify President Barack Obama’s decision to provide the federal funding that President Bush had denied. And more recently, after the 2015 video exposé on Planned Parenthood’s sale of body parts from aborted children, scientists claimed that tissue from elective abortion was indispensable for curing diseases and again appealed to the precedent set by using abortion-derived cell lines to produce vaccines.

Courageous and creative efforts on the part of individuals, organizations, and communities will be required to overcome this history and these ideological commitments. Some individuals may decide to provide witness by declining any vaccine that uses abortion-derived cell lines in one or more phases of development or production. Such a decision can be made in good conscience; however, such individuals must also take care to protect their own health and that of others as much as possible. Individuals and groups can band together to create petitions or engage in fundraising to facilitate the creation of alternatives. Finally, Catholic organizations have a crucial role to play in making alternatives available. Catholic universities with research programs should help to create alternatives. Catholic health care organizations should do all they can to preferentially purchase and distribute ethically sound vaccines that have no connection to abortion. Catholic organizations, from dioceses to nonprofit organizations, can join in these efforts.

An Existential Challenge

Even in the face of a devastating pandemic, it is not ethical to engage in moral evil for the sake of good motives or hoped-for results. Based on the ethical principles and Church guidance outlined above about remote material cooperation or remote benefitting from evil, people in this grave situation may discern in conscience to accept COVID-19 vaccines that utilize abortion-derived cell lines under protest or reject them. We should all be intensely aware of the moral evils it took to obtain the abortion-derived cell lines now in use. It is our grave duty to oppose any effort to justify, much less to extend, the actions of those who seek to benefit from the taking of innocent human life. At this significant moment of existential challenge, which also holds the potential for real scientific progress, we should redouble our demand for efforts to create alternatives to vaccines that utilize abortion-derived cell lines. Together, with courageous witness and hard work, we can help build a culture of life.

The Ethicists of The National Catholic Bioethics Center

Updated March 30, 2021

1 It is important to note that these are cells taken from fetal tissue isolated and grown independently. The abortion-derived cell lines do not involve human embryonic stem cells. When vaccines are grown in these cell lines, the cells are filtered out when the vaccine is extracted. Tiny fragments of DNA from the abortion-derived cells or other cells used are in the vaccine doses produced in this way. https://www.chop.edu/centers-programs/vaccine-education-center/vaccine-ingredients/fetal-tissues

2 Congregation for the Doctrine of the Faith, Dignitas personae (September 8, 2008), n. 35, emphasis original.

3 Pontifical Academy for Life, “Moral Reflections on Vaccines Prepared from Cells Derived from Aborted Human Foetuses,” reprinted in Linacre Quarterly 86.2–3 (May 2019): 182–287, doi: 10.1177/0024363919855896.

4 See Charlotte Lozier Institute, Update: COVID-19 Vaccine Candidates and Abortion-Derived Cell Lines, https://s27589.pcdn.co/wp-content/uploads/2020/12/COVID-19-Vaccine-Candidates-and-Abortion-Derived-Cell-Lines.pdf

5 For years many vaccines have been produced by growing weakened or altered versions of a virus in a cell culture— including abortion-derived cell lines—before collecting and distributing the virus through injectable doses. Some vaccines for COVID-19, including the Janssen-Johnson & Johnson and AstraZeneca–University of Oxford vaccines, are being produced by growing the SARSCoV-2 virus in an abortion-derived cell line.

6 See U.S. Food & Drug Administration, “Emergency Use Authorization,” March 4, 2021, https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization , which includes numerous links to additional information, including fact sheets and other information about each vaccine; U.S. Department of Health and Human Services, Emergency Use Authorization of Medical Products and Related Authorities: Guidance for Industry and Other Stakeholders (January 2017), available at https://www.fda.gov/media/97321/download .

7 U.S. Food & Drug Administration fact sheets for each vaccine available as of March 5, 2021 are hyperlinked here: (1) Pfizer-BioNTech, (2) Moderna, (3) Janssen (Johnson & Johnson).

8 John Paul II, Evangelium vitae (March 5, 1995), nn. 80, 81.

9 John Paul II, Evangelium vitae, n. 87.

10 Albert B Sabin and Peter K. Olitsky, “Cultivation of Poliomyelitis Virus in Vitro in Human Embryonic Tissue,” Proceedings of the Society for Experimental Biology and Medicine 34.4 (April 1936): 357–359, 10.3181/0037972734-8619C.

11 Just the creation of the WI cell lines, necessitated over 19 abortions. See M. Wadman, The Vaccine Race (Viking, 2017), at 59-85. The RA 27/3 cell line is named after the 27th abortion studied. Plotkin et al, Attenuation of RA 27/3 Rubella Virus in WI-38 Human Diploid Cell, 18 Am. J. Diseases of Children (Aug. 1969).