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UPDATED: Everything You Need to Know About Catholics and COVID-19 Vaccines


Due to the recent drop in vaccine demand, it is now more possible to choose which brand of vaccine you wish to take. Visit Vaccines.gov/search and choose the brand you more comfortable with and enter your ZIP code.

There is a lot of uncertainty among Catholics about the safety, efficacy, and morality of receiving the COVID-19 vaccines that are currently available in the United States. Here are some of the best resources we have found to help answer all of your questions.


Dr. Michael Deem from Duquesne University joined Al and took your calls on COVID-19
Al Kresta addressed Ave Maria Radio’s coverage of the COVID-19 vaccines on Kresta in the Afternoon.
Al Kresta explains why he doesn’t interview some critics of the COVID-19 vaccines on Kresta in the Afternoon.
Kresta in the Afternoon, 17 Mar 2021, Segment 4-1
Kresta in the Afternoon, 31 Mar 2021, Segment 4-1


Are the COVID-19 vaccines safe?

We have heard from many people who have concerns about the Pfizer and Modern vaccines because they are not traditional vaccines. It is true that these are the first mRNA vaccines to be approved in the United States. However, it is important to note that mRNA vaccines have been used in clinical trials in the past with no long term side effects.

There are actually quite few ingredients in these vaccines. This video, produced by Duke University, explains the ingredients in mRNA vaccines and why they are safe.

Here are some quick answers to some questions you may have:

Did these vaccines skip clinical trials so they would be approved faster?
No. They progressed through trials much faster than normal because they much more funding from the government and other sources than other clinical trials. Some have claimed animal testing was skipped. This process was not; it was conducted simultaneously with Phase 1 clinical trials on humans. No steps in the process were skipped.

If I am pregnant or breastfeeding, can I still take the vaccine?
Yes. mRNA vaccines do not contain the live virus. The only cause for concern may be normal immune responses such as fever or nausea. There is no evidence to suggest the mRNA vaccine adversely affects a pregnant woman or unborn child.

Do the vaccines prevent me from getting infected with COVID-19?
Yes. New CDC data has shown that the Pfizer and Moderna vaccines are 80% effective at preventing infection (not just severe illness as previously thought) two weeks after the first dose and 90% effective two weeks after the second dose in real world conditions.

Does my parish, a business, or an employer have the right to ask me if I have had a COVID-19 vaccine?
Yes. Medical law experts and Supreme Court precedent (dating back to the early 1900s) say that it is legal for businesses or your parish to ask if you have a vaccine. Businesses, schools, employers, and parishes have an obligation to protect public health. This is why vaccine records are required to attend most schools in the United States.

Dr. Cameron Wolfe, Duke Health infectious disease specialist, explains the safety of mRNA vaccines.

Do mRNA vaccines change your DNA?
No. mRNA is essentially a piece of instructions for your cell. It never enters the nucleus where your DNA is.

I read on the internet that this is gene therapy. Is that true?
No. Gene therapy involves introducing DNA into your cells. The Pfizer and Moderna vaccines are mRNA vaccines. They do not include DNA. They do, however, include RNA which is essentially a piece of instructions for your cell. It does not alter your DNA.

Haven’t the vaccines caused some people to die?
No. Some have claimed without evidence that there have been deaths linked to people receiving the COVID-19 vaccine. The Vaccine Adverse Effect Reporting System (VAERS) has had many reports of some reactions. A report in VAERS, however, does not mean that the event was caused by the vaccine. All vaccines have many reports, including death. The CDC and FDA investigates these reports and have not found any pattern that calls into question the overall safety of the COVID-19 vaccines.

Is the COVID-19 vaccine the mark of the beast?
No, for many reasons. Jimmy Akin answered this on Catholic Answers Live.

What about all the doctors that say you shouldn’t take it?
Some listeners have written to ask to ask about specific doctors and why we do not have them on our show to share their opinions. The bottom line is that most of them are not qualified to talk about COVID-19 or vaccines. Al Kresta explained this on Kresta in the Afternoon (you can listen above).
It is important to remember to always discuss decisions about your health with your own doctor.

Is it a violation of HIPPA and other privacy laws if someone asks I have had a vaccine?
No. As one medical law expert explained well, “HIPAA only governs certain kinds of entities – your clinician, hospital, or others in the health care sphere. It does not apply to the average person or to a business outside health care. It doesn’t give someone personal protection against ever having to disclose their health information.”

Read more: COVID-19 Vaccine Fact Vs. Fiction: An Expert Weighs in on Common Fears – University of California San Francisco

Read more: Anti-Vaccine Activists Peddle Theories That Covid Shots Are Deadly, Undermining Vaccination – Kaiser Health News

Read more: Who Has a Right to Ask if You’re Vaccinated? – University of Michigan Health


Are the COVID-19 vaccines moral?

This question is a little bit more complicated but the bottom line is this: the Church has said Catholics can take the vaccines that are currently approved in the US (this currently includes Pfizer, Moderna, and Johnson and Johnson). However, when a choice is given, one should choose the Pfizer or Moderna vaccines.

But I thought these vaccines were connected to abortions?

The Pfizer and Moderna vaccines did not use any cell lines connected to an abortion in their development. However, they both used the HEK-293 cell line, duplicated from an abortion in the 1970s, in their confirmatory testing. This is why the USCCB has said that these vaccines have a “very remote” connection to abortion.

(Read the USCCB Dec. 2020 statement on vaccines and the CDF Dec. 2020 statement on vaccines.)

The Johnson and Johnson vaccine used the PER-C6 cell line, which was duplicated from an abortion in the 1980s, in both its production and testing. This is why the Bishops have said that the Pfizer and Moderna vaccines are better options for the faithful. However, if you are not given a choice when receiving a vaccine, you may receive the Johnson and Johnson vaccine.
(Read the USCCB Mar. 2021 statement on the J&J vaccine.)

Due to the recent drop in vaccine demand, it is now more possible to choose which brand of vaccine you wish to take. Visit Vaccines.gov/search and choose the brand you more comfortable with and enter your ZIP code.

What about vaccine mandates?

We have had a number of questions regarding requirements to get a vaccine by public and private organizations. We have also received questions about “vaccine passports.” President Biden has said that he will not require vaccine passports as part of a national program. Other countries, however, might and that is their right to do so. This is also a fairly common practice now. For example, many countries require yellow fever vaccinations before a person can enter the country and American travelers must show a vaccine card from the CDC to prove they have had that vaccine.

It is possible that some private organizations may require vaccines. The Equal Employment Opportunity Commission has said private organizations can require their employees to be vaccinated. That being said, it is not likely most employers will do so since most employers do not want to be heavy-handed with their employees. Some large colleges, including Notre Dame and the University of Michigan, are requiring their students to be vaccinated before they return to campus. This is also legal and a regular practice. Most colleges and universities require meningitis vaccines.

As mentioned above, medical law and privacy experts have explained that asking if you have been vaccinated is not a violation of HIPPA or other privacy laws.

Is allowing vaccines connected to abortion a new development from the Vatican?

No, the Congregation for the Doctrine of the Faith released the document Dignitas Personae in 2008 and in it the CDF says there are certain instances when receiving a vaccine that has a remote connection to an abortion is morally acceptable.
(Read Dignitas Personae.)

The most common example of this is the Rubella vaccine. This vaccine used cell lines derived from an abortion in the 1960s. However, the suffering caused by complications from Rubella in children who contract the virus is serious. So, to promote the common good and to keep Rubella from spreading, parents can vaccinate their children with this vaccine.

(Read the National Catholic Bioethics Center article about abortion and vaccines.)

In the case of COVID-19, the Holy See and the USCCB argue that receiving the vaccine promotes the common good by curbing the spread of the virus. While it is true most people will not die from COVID-19, there are many of our brothers and sisters who are at high risk for severe illness. Recent studies have shown that the vaccines are helping to reduce the spread of COVID-19. That being said, Catholics are not morally obligated to get a vaccine, but those who refuse a vaccine must participate in other measures to help prevent the spread of the virus.

What about the Catechism’s teaching about cooperation with moral evil?

It is true that the Catechism of the Catholic says, “One may never do evil so that good may result from it” (Paragraph 1789). The Catechism, however, is not the end of the Church’s teaching. As the CDF December 2020 document explains, obtaining a COVID-19 vaccine is a material cooperation with evil, not a formal cooperation with evil. This distinction dates back to St. Alphonsus Liguori (1696-1787). Dr. Michael Deem, a bioethicist from Duquense Univeristy, explained in an article for the Pillar what the difference is between material and formal, and why is more significant than the other.

(The answer is quite long so we put in a drop down menu. Click on the + sign to expand the answer.)

Is the distinction about cooperating with evil rationalization of sin?

The formal-material distinction in Catholic moral thought dates back at least to St. Alphonsus Liguori (1696-1787), a Doctor of the Church and one its greatest moral theologians. However, the distinction appears to operate tacitly in magisterial teaching as early as Pope Innocent XI’s 1697 bull, Sanctissimus Dominus.

St. Alphonsus’s development of the distinction in his Theologia Moralis seems to have most influenced the Church’s moral teachings on cooperation with evil (in much the same way that Aquinas’s discussion of double effect influenced the Church’s moral doctrine). 

Understanding this distinction is critical to understanding the CDF’s and USCCB’s rationale for justifying acceptance of the COVID-19 vaccines.  The Archdiocese of Philadelphia has developed a useful chart for conceptualizing the formal/material distinction.

Cooperation in evil can be formal, where one contributes to the carrying out of a morally bad action either through sharing the intention of the principal agent, voluntarily and knowingly contributing to the carrying out of the principal agent’s willed action, or commissioning a morally bad action. For example, if I endorse or encourage someone’s intention to murder, or I intentionally act so as to contribute to the completion of the act of murder (e.g., by knowingly and willingly supplying the weapon used to carry out the murder, whether or not I shared the intention to murder), or I commission someone to perform murder (e.g., murder-by-hire), then I formally cooperate in the evil of the murder. Even though I do not perform the act of murder itself, I share moral responsibility. Thus, the Church holds that formal cooperation in evil is always morally wrong.

But cooperation in evil can also be material, where our actions do not bear on the intention or will of the principle agent, but rather contribute to or participate in the bad action itself. Material cooperation might range from directly or indirectly enabling another’s bad action – say by, to doing no more than merely participating in some distant manner in the outcomes of that bad action. The degree of one’s moral responsibility consequently co-varies with the degree of one’s cooperation in evil: formal cooperation entails full moral responsibility for the action in question, but moral responsibility diminishes as one’s material cooperation becomes causally more distant from the principle agent’s bad action – from immediate (we provide directly or indirectly the means for the bad action), to proximate mediate (we contribute in a non-necessary way to the principle bad action), and to remote mediate (we participate in the action or action’s effects).

The CDF, PAL, and USCCB have consistently maintained that acceptance of vaccines developed utilizing fetal cell lines is remote material cooperation in the evils of abortion and the posthumous injustice of using aborted fetus’s bodies for research. According to moral doctrine of the Church, while there is a moral duty to avoid evil – including cooperation in evil – there may be serious moral reasons that are proportional to (i.e., either roughly equivalent in gravity or outweighing) the duty to avoid remote material cooperation. In such cases, remote material cooperation in evil is permissible.

Find more helpful information here:

The ultimate Catholic coronavirus vaccine morality explainer – Pillar Catholic

Clarity for Catholics: It’s OK to get Johnson & Johnson COVID-19 vaccine – if it’s the only one available – USA Today

Bishops and vaccines: Why’d you have to go and make things so complicated? – Pillar Catholic

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