Which Covid-19 Vaccines use Cell Lines derived from the cells of an aborted fetus? And how are those cell lines used? There are three possible answers to these questions:

A. Some vaccines do not use Aborted Fetal Cell Lines (AFCLs). They use AFCLs neither in making the vaccine, nor in research and development of the vaccine. However, every vaccine and medicine today relies on a vast amount information from past research studies, and some of those studies have used AFCLs. There are no vaccines that have zero relationship to AFCLs. But for the purposes of this article, a rating of “A” means the furthest possible relationship to AFCLs: not in manufacture, not in research, only in that some information is from past distantly related studies that used AFCLs.

B. Some vaccines use AFCLs only in testing the vaccine or in the development. For example, AFCLs might be used to see if a vaccine produces the Coronavirus Spike protein in the cells. This is necessary to determine, so that researchers can be assured that the vaccine works in that particular step. When a certain type of vaccine is injected, it has to cause the human cells to make the viral protein (Spike protein in this case). And then the immune system reacts to that protein by making antibodies. A rating of “B” means that no AFCLs were used in manufacturing the vaccine, but AFCLs were used in testing the vaccine in the lab.

C. Some vaccines, especially the Adenoviral-vector vaccines, use AFCLs to produce the actual vaccine. These vaccines need to deliver to the cells in your body the gene for the Spike protein, so that your cells will make that protein, and then your immune system will make antibodies to the Spike protein. And they use an adenovirus from chimpanzees to deliver the gene. This adenovirus causes colds in chimps. A similar adenovirus causes colds in humans. They use the chimp version, so that the vaccine will not give you a cold. They also remove certain genes from the adenovirus, so that the virus cannot replicate and thereby make too many Spike proteins. (A vector carries the Spike gene into the human cells.)

So how does this adenovirus-vectored vaccine work? They put the adenovirus-vectored vaccine in AFCLs that have the genes missing from the adenovirus, so that the virus can then replicate. Many copies of the virus are then made, each copy lacks the genes for viral replication, but has the Covid-19 Spike protein gene. This becomes the vaccine. Since the virus used as a vector cannot make copies of itself, the only way to make the vaccine is to use AFCLs with the adenovirus genes for replication. This means that Covid-19 vaccines of this type, and only of this particular type, are manufactured inside of AFCLs.

Is it possible that the vaccine contains some of these aborted fetal cells from the cell line? No. The cells are very large compared to the size of the virus. There are no cells in the vaccine. However, there could be some molecules from the AFCLs in the vaccine. This is demonstrated by the reason these companies use AFCLs and not cell lines from human cancer cells (the other type of human cells used to make cell lines). They are concerned that some of the genes from the cancer cells might make it into the vaccine, and thereby cause cancer — so they do NOT use cancer cells for manufacture of any vaccine. But this means that part of the cells used to make this type of vaccine might make it into the vaccine itself. The amount of material is very low, and it is only a possibility. But this makes this particular type of vaccine the one more closely connected to the AFCLs.

In my theological opinion, any of these types of vaccines are moral, given a circumstance where the good effects outweigh the bad effects. The mere fact that a cell line from an aborted fetus is used in some way does not make the vaccine immoral. Church teaching is that such vaccines are not intrinsically evil, but are evaluated under the principle of material cooperation. By definition, that is a matter of weighing the good and bad consequences in the circumstances. So even a type “C” vaccine can be justified in this way.

I should point out that all these aborted fetal cell lines are cells thousands of cell-generations (cell divisions) subsequent to the fetus. So none of these cells or molecules in the cells were even in a fetus.

Also, this type of moral evaluation is based on good and bad consequences, since the cooperative act is not formal cooperation in intrinsic evil, nor is it explicit cooperation (meaning the intention to cooperate in the evil act of, in this case, abortion). And when we evaluate circumstances, a mere physical and remote connection does not weigh as a bad consequence. If a former abortion clinic is now used as a free clinic, run by prolife doctors, for treating a wide range of illnesses in those without healthcare, the fact that the location used to be used for abortions does not make the clinic or its work evil. It is largely irrelevant. If a murder-victim is an organ donor, his organs can be used in medicine to treat those in need of a transplant.

However, it is possible with current medical technology (e.g. induced pluripotent stem cells from an adult human being) to make a new cell line that will replace these AFCLs. We just need laws to pressure companies to make these cell lines.

Please note that sometimes the distinction between B and C is difficult to determine as there are many experiments needed in R&D before making a vaccine. Personally, I think all of these vaccine types are potentially morally justifiable depending on the circumstances; even type C vaccines are justifiable, if you have no other vaccine option and it will save lives.

On the other hand, it is not a moral requirement for everyone to be vaccinated. Persons who might die from the side effects (possible in frail elderly persons); persons who have longcovid or ME/CFS should not receive the vaccine; persons who had Covid-19 and recovered do not need it; persons who are allergic to a component of the vaccine, or who have reason to think they will respond badly to the vaccination are not required to take it, morally. It is an evaluation of the circumstances. Consider the good of others and of society, as well as the risk/benefits to yourself and your family.

Sorry for the long introduction. Here are the vaccine ratings:
Note well that these ratings ONLY apply to the more or less remote relationship of the vaccine to aborted fetal cell lines. An “A” rating does not imply that the vaccine is the best vaccine, nor does it imply that the vaccine is most effective or most safe. Nothing is implied about these vaccines in their effectiveness or safety by these ratings, except relationship of vaccine to AFCLs

Novavax vaccine “A” (recombinant nanoparticle vaccine)
EpiVacCorona vaccine (peptide type) “A” made in Russia
Covaxin by Bharat Biotech in India “A” (inactivated virus)

Moderna mRNA vaccine “B”
Pfizer mRNA vaccine “B”
AstraZeneca vaccine “C”
Johnson and Johnson vaccine “C”

Sputnik V from Russia “C” — this is a non-replicating viral vector, which makes it likely that they had to use AFCLs to manufacture it. If not, then they would have had to use cancer cell lines. In either case, this vaccine would be a last choice for vaccination.

Sinovac (inactivated Covid-19 virus) A or B, not C – this type of vaccine is not manufactured using AFCLs, but there is not enough information to discern whether those cell lines were used in R&D. It was developed and is made in China. I trust the researchers and physicians in China, but not the government. If you live in China and it is your only option, it may be moral.