For what it's worth some other countries are now looking to extend the period between doses [Link] due to the data coming in regarding the success of the first dose. As you rightly say there are unknowns in diverging from the dose regimen of the study (where time was of the essence!).

In some quarters there have been concerns that delaying the second dose could increase the likelihood of resistant strains [Link]

Emerging data, at least with the AstraZeneca vaccine, points towards a longer period between doses increasing efficacy [Link] . Of course this is only one study though, and who knows if it's applicable to other vaccines - Pfizer etc.

(Interestingly, in the Oxford study they initially thought that half dose - full dose made the vaccine more effective, before later factoring in that there was a longer period between dosing in that sub group [Link] )

The second Pfizer dose increases antibody levels very significantly accordingly to their data and real world studies [Link] . While one dose appears to be very effective against covid-19, it would appear that the South African variant for instance may make it 2/3 less effective [Link] . With that in mind, and the fact that they currently have little idea of what level of antibodies are actually required to fend off the virus, I can certainly appreciate concerns in having to wait. It's feasible that it may end up being a good call (due to these new strains not currently being as widespread, plus 'possibly' increased efficacy with a longer wait). It's a tricky balancing act no doubt. Lots of unknowns, with a government somewhat winging it in the decisions that they make on our behalf.

Edited by BlueJay (18 Feb 2021 5.40pm)

That’s alright then. He is so credible

Yes, I can see why as the weeks tick by some would start to be concerned about the various unknowns at play. Especially those without a second appointment lined up so far. Hopefully they haven't over extended themselves with this first dose push across groups to the point where there are even delays even beyond 12 weeks.

As you rightly say, there are knowledge gaps and a degree of flying blind. Fingers crossed that through fortune as much as anything else the roll out ends up providing as much protection as is possible, putting us in a much better position going forward.

Got my first jab tomorrow I just turned 60 so I am delighted.

One more point

Good news from Pfizer hopefully this will help the roll out.

[Link]

One more point

Just read that israel are going to vaccinate 100k Palestinians who work in israel. We could see some unexpected benefits from this sad moment in time.