First, it is a mortal sin if you did this with full conscience of its graveness. Second, if you did this with full freedom. But I think the overwhelming majority of Catholics who accepted the vaccine do not have full freedom because of the continuous pressure of the environment, even from their pastors and from the Pope.
The Pope continuously says, “Please take the vaccine”, and even the bishops. For me, this diminishes people’s freedom and it also diminishes the full conscience of the moral gravity of these vaccines. The Vatican issued documents saying that you can do this. There are some priests, even traditional priests, priests from the Society of Pius X, and priests from the Fraternity of St. Peter, who told everyone that it is okay to take these vaccines because of the theory of cooperation, and so on.
So, in this case, in my opinion, these people did not commit mortal sin because they followed this unfortunately erroneous advice. They can simply confess if their conscience troubles them but they can still go to Holy Communion. Of course, just like how we confess our venial sins, it is okay to confess these sins in confession.
We should also confess our imperfections and not just our mortal sins. Maybe the lack of concern to study these vaccines beforehand is an imperfection. In any case, I do not consider this a mortal sin but if they keep receiving these vaccinations then I think they are more conscious and more responsible for it now than they had first received it.
Dear visitors of Gloria Dei and all who have already written or who will write a personal message to me. I am grateful for your attention, your kindness, for your spiritual support and especially for your sacrifices and prayers for me. God may reward you!
