There is a suggestion in the media that giving the Astrazeneca vaccine to the over 65s doesn’t work very well and so some Continental Europeans won’t be using it…So Good news for the Youngers who are less at risk as there will be more to go round, but nothing for the retirees…
Seems the New Headline is : No work No vaccine, sadly if means less options for some of our parents in BartsMS parents. However, most of you are not over 65 so no need to wory and if you are over 65, no need to worry. In the trial there were 56/15,980 =0.350438% and it seems 2/660 over 65 get disease = 0.303030%. Were old people less susceptibile that young people or is it that older people weren’t mingling as much?
The numbers are to day to say anything about efficacy except do more studies.
According to the MHRA website
“The level of protection gained from a single dose of COVID-19 Vaccine AstraZeneca was assessed in an exploratory analysis that included participants who had received one dose. Participants were censored (removed) from the analysis at the earliest time point of when they received a second dose or at 12 weeks post dose 1. In this population, vaccine efficacy from 22 days post dose 1 was 73.00% (95% CI: 48.79; 85.76 [COVID-19 Vaccine AstraZeneca 12/7,998 vs control 44/7,982])”.
So this is based on about 16,000 people.
Overall, among the participants who received COVID-19 Vaccine AstraZeneca, 94.1% of participants were 18 to 64 years old (with 5.9% aged 65 or older); 60.7% of subjects were female; 82.8% were White, 4.6% were Asian, and 4.4% were Black. So few old people and few non-white people got the vaccine
Indeed MHRA say there “were only 660 participants ≥65 years old were too few to draw conclusions on efficacy” as only two people had got COVID, so you have 1 and 1 in each group or 2 and 0. So if this group does not get vaccinated in Germany/EU if the news is correct. They are doing what the European Medicines agency do and say “the data isn’t good enough”. We won’t approve it. That is fine. This what the EMA (or should I say countries in the EU) have done and I guess the FDA in the States may do. More trials may be in order and are planned
This will delay access to this vaccine mean more for countries like: UK, Hungary, Argentina, El Salvador, Dominican Republic, India, Bangladesh, Mexico, Nepal, Pakistan, Brazil, Saudi Arabia, Iraq, , Thailand (Who have approved the Astrazeneca vaccine (RAPS.org vaccine tracker).
However, the biological effect of the vaccine young and old does not suggest much difference between over and under 65s
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32466-1/fulltext Ramasamy et al. VOLUME 396, ISSUE 10267, P1979-1993, DECEMBER 19, 2020
This shows that the level of antibodies increase for a month after the first dose and then it plateaus. But if you get the second dose the antibody levels increase further. There is very little diffference if you are over 70 or 55-69years old
If you look at the viral inhibition it is very similar between young and old
Now the T cells… the T cells are activated after the first dose and there is not alot of difference between the 18-55 to the over 70years
So the over 70s are a bit lower but not that much lower. So if there is a reduction in protection in the oldies it suggests it is not because of the adaptive immune system. As I have said many time the important cell types getting rid COVID-19 virus are cells from the Innate Immune system. The macrophages are the important cell types and this is why MS DMT do not affect Covid-19 very much. Macrophages are less effective as we age, which is why we don’t repair as quick. However immunology 101 says if you have an immune response it is likely that you will get rid of the virus quicker than not having an immune response against it.
High seroconversion (developing an antibody response) rates were observed in older adults (more than 65 years) after the first (97.8%; N=136) and the second recommended dose (100.0%; N=111).
Adverse reactions were generally milder and reported less frequently in older adults (≥65 years old).