Is There a Moral Obligation to Be Vaccinated for COVID-19?*

March 24, 2022
Feature Article

Jason T. Eberl, Ph.D.

As the COVID-19 pandemic surges with the highly infectious Omicron variant, while cases of the less infectious but deadlier Delta variant persist, debates concerning vaccination mandates have not subsided. The Catholic Medical Association (CMA) and the National Catholic Bioethics Center (NCBC) argue for exemptions for those who object to receiving a COVID-19 vaccine for religious or moral reasons.2 Yet, several Catholic prelates have instructed their priests not to sign religious exemption requests or have mandated vaccinations for diocesan employees, and Vatican City has instituted a mandate without allowing non-medical exemptions.3 I argue that principles of secular public health and Catholic social ethics justify such mandates. I further show why certain objections Catholics may have are ill-founded and conclude that there is no moral reason for a Catholic to refuse to be vaccinated for COVID-19; rather, it is a moral obligation.4

Ethical Principles Supporting COVID-19 Vaccination Mandates
The commonly-held principles of biomedical ethics — respect for autonomy, nonmaleficence, beneficence, and justice — are primarily applicable in the clinical and research contexts, in which the primary concern is the protection of individual patients or research participants.5 A complementary set of principles for the public health context primarily concerns the general welfare of society, which may be impacted by individuals' choices.6 The first principle stipulates that one's liberty may be restricted to prevent risk of harm to others7 — and there is ample evidence of the risks from lack of vaccination.8 If restriction of liberty is warranted, the least restrictive means should be used: one should start with education, then inducement, and, if such measures are not effective and the public health threat is sufficiently significant, coercive or punitive measure may be employed — we have witnessed each of these steps since the vaccines became available. Reciprocity demands that mandated vaccines be made freely available and also informs efforts to minimize the penalties for those who choose not to be vaccinated under a mandate — such as requiring regular testing or mask-wearing,9 or reconfiguring one's job (e.g., reassigning a nurse to perform non-patient-facing functions within a hospital). Finally, transparency demands that all stakeholders have a voice in the public deliberation and ultimate determination of public policy, which does not entail that all stakeholders will get their way.

These secular public health principles cohere with key principles of the natural law and Catholic Social Teaching. We begin with Thomas Aquinas's exhortation to exercise proper stewardship over one's body: "It is prescribed that a human being sustains his body, for otherwise he murders himself. … Therefore, one is bound to nourish his body, and we are bound likewise with respect to all other things without which the body cannot live."10 There is both a personal moral obligation to safeguard one's health and an obligation for public authorities to help cultivate this and other virtuous dispositions: "Legislators make men virtuous by habituating them to virtuous works by means of statutes, rewards, and punishments."11 Aquinas defines civil laws as those made by appropriate authorities, utilizing prudential reason to craft ordinances that serve the common good.12 Vaccination mandates that have been made by public authorities, and within Catholic health care and educational institutions,13 having reasoned through the relevant epidemiological evidence, are licit expressions of civil law serving the common good and fostering a more virtuous citizenry.

The common good is "the sum total of social conditions which allow people, either as groups or as individuals, to reach their fulfillment more fully and more easily."14 The Catechism further exhorts, "The dignity of the human person requires the pursuit of the common good. Everyone should be concerned to create and support institutions that improve the conditions of human life."15 Concerning the proper function of public authorities, the Catechism concludes, "It is the role of the state to defend and promote the common good of civil society"16 and that "it is the proper function of authority to arbitrate, in the name of the common good, between various particular interests."17 Insofar as vaccination mandates create a social condition — herd immunity18 — that allows people to reach their fulfillment more fully and more easily — and it is evident how the pandemic, particularly when lockdowns and social-distancing have been required, has inhibited such fulfillment in terms of the economy, education, and mental health19— the state is fulfilling its proper role to promote the common good and respect the dignity of the human person. Furthermore, the common good requires considering the "sum total" of relevant social conditions while also keeping in the forefront the Church's exhortation of a preferential option for the poor and vulnerable.20 Hence, the vulnerability of persons who cannot be vaccinated for medical reasons, the economic impact of lockdowns and quarantines, the amelioration of politically-created health disparities,21 and the particular vulnerabilities experienced by persons with disabilities22 should be taken into account.

Ill-Founded Conscience-Based Objections to COVID-19 Vaccination
The primary basis for refusals to be vaccinated on the part of pro-life Catholics is a remote material causal link to abortion. The Johnson & Johnson/Janssen vaccine was manufactured using an immortalized cell line (PER.C6) that was developed from the retina of a fetus aborted in 1985; the Moderna and Pfizer/BioNTech vaccines were tested using a cell line (HEK 293) developed from the kidney of a fetus that either was aborted or had naturally miscarried in 1972.23 The Congregation for the Doctrine of the Faith (CDF) has ruled definitively that "it is morally acceptable to receive Covid-19 vaccines that have used cell lines from aborted fetuses in their research and production process."24 Without delving into the details of how the CDF arrived at this conclusion,25 it is evident that Catholics who seek an exemption from a vaccination mandate due to the remote — and, in the case of the Pfizer/BioNTech and Moderna vaccines, merely probable26 — material connection to past abortions are operating from a misinformed conscience that public authorities need not respect,27 especially since these cell lines have been used to develop other pharmaceuticals, cosmetics, and processed food additives with. no moral objections being voiced.28

The CMA and NCBC have centered their call for exemptions on the requirement for authorities to respect the right to express one's conscience, citing the Catechism:

Man has the right to act in conscience and in freedom so as personally to make moral decisions. 'He must not be forced to act contrary to his conscience. Nor must he be prevented from acting according to his conscience, especially in religious matters.'29

The Church's teaching on the nature of conscience, however, is nuanced in ways not explicitly appreciated by these organizations.30 For example, this quotation is derived from Vatican II's declaration on religious freedom, a document primarily concerned with totalitarian political regimes — primarily Nazism and Soviet-style communism — that inhibit the practice of religious faith, religious education, missionary outreach, etc. The above assertion does not directly entail that public authorities have no role to play in restricting certain behaviors — conscientious though they may be — that threaten the common good:

The right to religious freedom is exercised in human society: hence its exercise is subject to certain regulatory norms. In the use of all freedoms the moral principle of personal and social responsibility is to be observed. In the exercise of their rights, individual men and social groups are bound by the moral law to have respect both for the rights of others and for their own duties toward others and for the common welfare of all. Men are to deal with their fellows in justice and civility. … Furthermore, society has the right to defend itself against possible abuses committed on the pretext of freedom of religion. It is the special duty of government to provide this protection.31

[N]ot a few can be found who seem inclined to use the name of freedom as the pretext for refusing to submit to authority and for making light of the duty of obedience. Wherefore this Vatican Council urges everyone, especially those who are charged with the task of educating others, to do their utmost to form men who, on the one hand, will respect the moral order and be obedient to lawful authority, and on the other hand, will be lovers of true freedom-men, in other words, who will come to decisions on their own judgment and in the light of truth, govern their activities with a sense of responsibility, and strive after what is true and right, willing always to join with others in cooperative effort. Religious freedom therefore ought to have this further purpose and aim, namely, that men may come to act with greater responsibility in fulfilling their duties in community life.32

The Church's carefully balanced view eschews the subjectivism entailed by defending a right to conscience as an absolute and denying that just civil laws bind one's conscience.33 John Paul II echoes this concern:

The individual conscience is accorded the status of a supreme tribunal of moral judgment which hands down categorical and infallible decisions about good and evil. To the affirmation that one has a duty to follow one's conscience is unduly added the affirmation that one's moral judgment is true merely by the fact that it has its origin in the conscience. But in this way the inescapable claims of truth disappear, yielding their place to a criterion of sincerity, authenticity and "being at peace with oneself", so much so that some have come to adopt a radically subjectivistic conception of moral judgment.34

The Vatican II Fathers connect this concern regarding "individualistic morality" with safeguarding the common good, including "the protection of health":

Profound and rapid changes make it more necessary that no one ignoring the trend of events or drugged by laziness, content himself with a merely individualistic morality. It grows increasingly true that the obligations of justice and love are fulfilled only if each person, contributing to the common good, according to his own abilities and the needs of others, also promotes and assists the public and private institutions dedicated to bettering the conditions of human life. Yet there are those who, while possessing grand and rather noble sentiments, nevertheless in reality live always as if they cared nothing for the needs of society. Many in various places even make light of social laws and precepts, and do not hesitate to resort to various frauds and deceptions in avoiding just taxes or other debts due to society. Others think little of certain norms of social life, for example those designed for the protection of health … they do not even avert to the fact that by such indifference they imperil their own life and that of others.35

Carter Snead has rightly criticized the "expressive individualism" embodied by most public bioethics laws in the U.S.,36 but Catholics must be careful not to utilize the same foundation of the expression of individual autonomy — recast in the name of "conscience" — above other moral concerns, such as public health as partially constitutive of the common good.

Moral Obligation to Be Vaccinated for COVID-19
The CDF states that, while receiving the COVID-19 vaccines is permissible, "vaccination is not, as a rule, a moral obligation and that, therefore, it must be voluntary."37 On this basis, the CMA and NCBC defend exemptions to mandates. However, there are a couple key ambiguities in the language the CDF uses.38 First, there are two ways in which something could be a "rule": absolutely or prima facie. Understanding the CDF as asserting an absolute rule would contradict Pope Francis's exhortation, "I believe that morally everyone must take the vaccine. It is the moral choice because it is about your life but also the lives of others."39The Pope and the CDF would be in alignment if we understand "as a rule" in a prima facie sense, meaning that, under ordinary circumstances, vaccination is not a moral obligation; however, the current pandemic has arguably created a "state of exception" in which moral rules, though not abrogated, may be applied in different ways.40 In this case, another moral rule — the requirement to safeguard one's health and promote the common good — overrides the prima facie rule against vaccination being a moral obligation. Second, the term "voluntary" is inherently ambiguous as it could mean either that one should not be coerced in any way to be vaccinated or that one should not be held down and jabbed against their will. While mandates could be construed as "coercive," they are not forcing anyone to be vaccinated against their will.

I conclude that there is a moral obligation to be vaccinated based on epidemiological evidence that vaccination — except for those with medical contraindications41 — is the most effective means of fulfilling one's duty to safeguard their own health and promote the common good, which inherently respects the dignity of human persons, particularly those at higher risk of severe illness or death — including by attenuating the virus' potential to mutate into more infectious and deadlier forms. No countervailing moral reason of sufficient weight to forego vaccination has been provided by Catholic or secular critics of vaccination mandates.

Jason T. Eberl, Ph.D.
Professor of Health Care Ethics and Philosophy
Director, Albert Gnaegi Center for Health Care Ethics
Saint Louis University
St. Louis

[email protected]


  1. *This essay develops further arguments initially put forth in three previous essays:,, and, as well as a series of podcasts (Episodes 76-78) sponsored by the National Catholic Bioethics Center: All links throughout accessed 28 December 2021.
  2. See and
  3. See;;; (the Vatican City mandate allows for proof of previous COVID-19 infection in place of vaccination).
  4. I set aside legal debates regarding the constitutionality of governmental mandates or whether mandates by employers are discriminatory, as well as the disputed question of whether previous COVID-19 infection provides sufficiently robust immunity—equivalent to or better than the currently available vaccines in efficacy and duration of protection—to warrant an exemption from vaccination:
  5. See Tom L. Beauchamp and James F. Childress, Principles of Biomedical Ethics, 8th ed. (New York: Oxford University Press, 2019).
  6. See R.E.G. Upshur, "Principles for the Justification of Public Health Intervention," Canadian Journal of Public Health 93:2 (2002): 101-3.
  7. The historical root of this "harm principle" may be found in John Stuart Mill's seminal essay "On Liberty."
  8. Not only are the vast majority of COVID-related hospitalizations and deaths among the unvaccinated (, the mutation of the SARS-CoV-2 virus into new variants is correlated with lower levels of vaccination (
  9. Though such measures may be insufficiently effective against the Omicron variant. Vatican City's vaccination mandate previously allowed for regular testing as an alternative, but it recently disallowed this alternative as the Omicron variant has surged.
  10. Thomas Aquinas, Super secundam Epistolam ad Thessalonicenses lectura, cap. III, lect. 2; my translation.
  11. Thomas Aquinas, Commentary on Aristotle's Nicomachean Ethics, bk. II, lect. 1, §251; trans. C.I. Litzinger (Notre Dame, IN: Dumb Ox Books, 1993).
  12. Thomas Aquinas, Summa theologiae, Ia, q. 95; trans. English Dominican Fathers (New York: Benziger, 1948).
  13. See and
  14. Gaudium et spes (1965), n. 26:
  15. Catechism of the Catholic Church (1997), n. 1926:
  16. Ibid., n. 1927.
  17. Ibid., n. 1908.
  18. See
  19. See;;
  20. See
  21. See Daniel E. Dawes, The Political Determinants of Health (Baltimore: Johns Hopkins University Press, 2020).
  22. See, and Tom Shakespeare, Florence Ndagire, and Queen E Seketi, "Triple Jeopardy: Disabled People and the COVID-19 Pandemic," The Lancet 397:10282 (2021): 1331-3.
  23. See
  24. CDF, "Note on the Morality of Using Some Anti-COVID-19 Vaccines" (2020): (emphasis original). This position was recently reaffirmed by the Pontifical Academy for Life:
  25. Further justification of the CDF's position has been provided by prominent Catholic pro-life scholars:
  26. As Becket Gremmels suggested in correspondence, objections to HEK 293-derived vaccines (which also includes the AstraZeneca vaccine used outside the U.S.) may be expressions of rigorism or tutiorism, which demand 100% certainty that no directly intended abortion was involved.
  27. One who acts from a misinformed conscience may be excused from moral culpability if their conscience is misinformed due to invincible ignorance, but not if one's ignorance is caused by willfulness or negligence; see Aquinas 1948, Ia-IIae, q. 19, a. 6.
  28. See
  29. Catechism, n. 1782.
  30. See
  31. Dignitatis humanae (1965), n. 7:
  32. Ibid., n. 8.
  33. Aquinas 1948, Ia, q. 96, a. 4.
  34. John Paul II, Veritatis splendor (1993), n. 32:
  35. Gaudium et spes, n. 30.
  36. O. Carter Snead, What It Means to Be Human: The Case for the Body in Public Bioethics (Cambridge, MA: Harvard University Press, 2020).
  37. CDF 2020.
  38. For a similar interpretation of this statement, see Peter J. Cataldo, "Why the CDF Note on the Morality of Using Some Anti-Covid-19 Vaccines Suggests a Moral Obligation to Receive SARS-CoV-2 Vaccines" Health Care Ethics USA (Fall 2021):
  39. The Pope continues, "There is a suicidal denialism that I would not know how to explain but today people must take the vaccine." Francis reiterated his call to be vaccinated in a Spanish-language PSA with several other prelates: One could view this PSA as a form of public fraternal correction for the sake of the common good, which is a proper function of prelates; see Aquinas 1948, IIa-IIae, q. 33, a. 3.
  40. Other examples of "states of exception" include just war and circumstances of dire material scarcity; see Jason T. Eberl, "Unilateral Withdrawal of Life-Sustaining Treatment within Crisis Standards of Care" Health Care Ethics USA (Winter 2021):
  41. See

  • Jason T. Eberl, Ph.D.