Welcome to the forum Rob20. You may have noticed a frosty reception to your arrival here. There have been a few trolls recently so bear that in mind.
The article you posted was in Portuguese so I can't understand exactly what they are claiming. The study they cite seems to come from Butantan, the largest vaccine manufacturer in Brazil. I've not found the original study they published so am unable to comment much about it.
The clinical trial in Chile is the only one I'm aware of that subdivided age groups older than 60 and I believe the effectiveness was 65% for the 80+ age group.
That was before emergence of newer variants though and the effectiveness of any vaccine tends to be poorer in that demographic.
Thank you very much for the welcome,
sincerely I had not seen the Chilean study and its inclusion of people over 70 years of age, for what it says, the vaccine offers good immunity, and is a good contrast to what was published in Brazil
Why the study that you linked is outstandingly alone from studies from other countries, namely China, Turkey, Chile, Indonesia and Philippines? Back in school, if a student got a different result than everybody else, the first thing to do is to re-examine oneself's calculation, and 99.99% times it was his/her fault.
I was not aware that there were other studies that included people over 70 years old, apparently there is another in Chile in this regard ... I was only curious about the low efficacy in older people
Trying to investigate a little more than what was published in Brazil, I have realized that one of those who has carried out the study is a researcher from FIOCRUZ who in Brazil is the one who produces the Astrazeneca Vaccine, it is probably not such an impartial study how was believed
On the other hand, it only talks about the general efficacy against symptomatic cases, there are no data on effectiveness for severe cases.