Fetal cells and Covid-19 vaccines: Can Thomas Aquinas help?

Ethical concerns have been raised about aborted human fetal cells being used in the creation of some Covid-19 vaccines. Should this preclude their use?

Vaccines developed from fetal cells lines are not new. Pharmaceutical companies have found fetal cell lines to be perfect for growing vaccines. These fetal cell lines were originally derived in the 1970s and 1980s from two elective abortions that were not performed for the purpose of vaccine development.

Fetal cell lines have already been used to create vaccines for diseases such as hepatitis A, rubella, and rabies. Only two fetal cells lines are being used: HEK-293 – a kidney cell line that was isolated from a terminated fetus in 1972; and PER.C6 – a retinal cell line that was isolated from a terminated fetus in 1985. No other fetal cells from aborted fetuses have been used and no new abortions have been carried out since in order to obtain new fetal cell lines.

No vaccines of any kind contain aborted fetal tissue and of the various Covid-19 vaccines, only live attenuated or inactivated virus vaccines and viral vector vaccines have used fetal cell lines in their production. Some of these have used animal cell lines while others have used human fetal cell lines. Examples are AstraZeneca, CanSino, Gamaleya (Sputnik V), and Janssen. Other DNA, RNA and Protein vaccines do not require fetal cell lines for their development. Examples of RNA vaccines are the Pfizer and Moderna vaccines. For a full list see: COVID-19 Vaccine Candidates and Abortion-Derived Cell Lines.

For those who are concerned about the moral implications of using vaccines produced using aborted fetal cells, the RNA, DNA, and Protein vaccines will not be a problem. It is only with live attenuated or inactivation vaccines that a potential problem arises.

I believe that Thomas Aquinas, one of the greatest theologians of the church offers some wisdom on this issue. From Thomas Aquinas, we learn of the principle of natural law, the principle of totality, and the principle of double effect.

The principle of natural law states that the ‘Natural Law consists of first judgment that good should be pursued and evil avoided’. It means that all moral actions should seek the greater good and not greater harm. What is a vaccine for the greater good? It will give some protection for the vulnerable and those at high risk, especially older people, those with other chronic medical conditions, and those whose immune systems are weak. It will also aim to create herd immunity to protect those who have not yet been infected. Under natural law, we should aim to do good, not evil.

In his second principle, the law of totality, Aquinas noted that ‘the body may be changed only to ensure proper functioning of the whole body’. He pointed out that it is our duty to be responsible stewards not only of our own bodies but also of our neighbours’ bodies. Such vaccines will strengthen the body’s defences against the virus. Aquinas was not aware of vaccination but he was aware of plagues and pestilences.

Aquinas’ third and final principle is double effect. Aquinas taught that ‘the act must be good or at least morally neutral. The moral agent must intend only the good effect and bad effect must not be the means of bringing about the good effect. The good and the bad effect must be proportional.’ He was saying that sometimes a given action may have two outcomes, one good and one bad.

For example, in ectopic pregnancy, where the embryo is implanted not in the uterus but in a fallopian tube, life threatening haemorrhage may ensue and a doctor may have to remove the fallopian tube containing the embryo to save the mother’s life. The baby cannot be saved in any circumstance and without an operation, both mother and embryo will die. The principle of double effect decrees that as the intention was to save the mother’s life in circumstances where the fetus could not be saved, the action was admissible. Another example might be where strong pain relief, which may impair respiration, is given with the primary intention of relieving pain. Suppression of respiration is not intended but it may be foreseen as a risk of adequately easing pain.

This is very different from saying that the end of saving life through vaccines in some way justifies the means of taking early life through abortion. That would be saying that the end justifies the means and that is unethical.

But if a morally wrong act (abortion) can later be turned for good (the making of vaccines) by someone who was not complicit in or approving of the original act that is morally different.  

Aquinas’ teaching may have an impact on how we think about fetal cell lines. These fetal cells line were derived from two abortions done 30-40 years ago. Yet these fetuses have provided a legacy to ensure that others keep on living.

Ultimately, the choice is yours. As I have mentioned, not all Covid-19 vaccines are made from human fetal cells. What is essential is that enough people need to be vaccinated both for their own individual and their neighbours’ protection.


For the Vatican’s directive, see: CONGREGATION FOR THE DOCTRINE OF THE FAITH, Note on the morality of using some anti-Covid-19 vaccines (21 December 2020)

Dr Alex Tang is a Paediatrician and Practical Theologian from Johor Bahru Malaysia. This article is reproduced with permission from his website.

3 Comments

  1. Maria Cowan on 29 March 2021 at 7:24 pm

    I think it is terrible to try to save the lives of old people using the lives of the unborn who have not had the chance to be born. This has created an industry of producing babies to be aborted in order to create vaccines specially for old people. What a terrible crime. Old people have had at least the chance to live; to see flowers, to enjoy the sun, to drive a car, etc. How unhuman ir is to Kill babies with the excuse to make vaccines to save lives. A horrendus crime!

    • Kellee on 5 September 2021 at 1:35 am

      In total agreement!

    • Cornelia Staehelin on 19 October 2021 at 9:41 pm

      No abortions are done to create vaccines ! Please read the article again and please try to accept that your preset idea is wrong. This correct: no abortions were EVER performed in order to create vaccines!

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