Does anyone have a simple explanation of the differences in physiology between say a 55 and 65 year old that makes AZ unsafe for the younger person but safe enough for the older. (Is there any other medications that have such distinct age distinctions)
Yes. Dr Norman Swan explained this on the recent coronacast. Basically as you get older your immune system response is weaker and you are less likely to clot although the mechanism is not fully understood. However he said it's a sliding scale with continuous variable of risk that declines as your get older ... there is no hard and fast age where you are safer getting or not getting it. They have to pick an age as a cutoff and therefore they went for age 60.
He discusses it here about 6:40 in.
I've had my first Astra shot. What now? - ABC listen
The national vaccine rollout has suffered another setback, with the federal government now saying that only people over 60 years should get the AstraZeneca vaccine. It's likely to set the date to full vaccination back even further as Pfizer vaccine supplies are limited and it'll be months...
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