Must confess to getting increasing concern about #sarscov2 #vaccine #effectiveness claims.
The real data we need to see is either prevention of infection or reduction in transmission risk in lee-vulnerable groups and/or effectiveness in vulnerable groups.

The former would require regular longitudinal monitoring/testing of vaccine recipients (difficult, but not impossible to do at scale), looking for direct evidence of infection (not symptom-reporting)

The latter would need a dedicated phase 2/3 trial specifically focussing on vulnerable groups, who despite shielding etc. are still getting exposed (as our hospital/ICU admission rates will testify)

My fear is that these important experiments, especially protection in vulnerable groups, might happen in real-time after licensing. That's not a problem provided people realise that the vaccine might not have been fully validated/proven in this group. Let's see