A friend of mine who is in the 65 to 69 age group got notification of his appointments today. Judging by the distance between the appointments I am pretty sure that he is getting the AstraZeneca vaccine. His wife, who came in the 60 to 64 age group, already received the AstraZeneca and other friends, who are in the 70 to 74 age group, are also probably due to get the AstraZeneca vaccine, again judging by their appointment spacing. All in the Chania area.
Generally Greece has stressed that it is following EMA advice. Initially it restricted AstraZeneca to under 65, even though the EMA approved it for all ages over 18. There was no concern about safety in the older age group but there was a small concern about efficacy. Efficacy in a trial is judged by how many people who were vaccinated caught COVID compared to how many who weren't vaccinated. If 100 people caught COVID, of which 98 had not been vaccinated and 2 had, then the efficacy is 98 %. In the trial too few people over 65 caught COVID at all to make such a judgement with a high degree of certainty. There was indirect evidence in that people over 65 had antibody tests done, which showed that they had developed a high level of antibodies, so the EMA approved it for over 65s on that basis but Greece decided to be a little cautious. Once a vaccine is approved and being administered the collection of data continues with a much bigger sample size than in the trial. That showed, with direct evidence, that the efficacy of the AstraZeneca vaccine was high and so Greece abandoned its cautious approach and started administering it to older people. The Greek decision did not delay the vaccination programme at all but moved some younger people slightly ahead in the queue.
It is worth stressing that all the vaccines seem to have around 100 % efficacy in preventing advanced symptoms, hospitalisation and death. It is often not clear if the few vaccinated people who still catch COVID do so either in the period before full antibody levels have developed or possibly because of a variant that is resistant to the vaccine.