Wanted to address this one-dose, two-dose vaccination question. NO ONE to my knowledge is suggesting that one dose only be given; suggestion was whether 2nd dose could be given later to allow current supplies of 1 dose to vaccinate more. What would be evidence for this?
In the AstraZeneca/Oxford trial, Lancet paper did not mention this but the data presented to UK showed that extending time between doses led to MORE immunogenicity. Here is slide below (12 weeks >9 weeks >6 weeks) 
Known in vaccine world that we don't want too short of an interval between doses, okay to give booster shots after a long time (which is why - if childhood vaccines have gaps- we just start where we left off, not repeat). Why 2 doses better than one? To build memory immune system
Okay so you will say - but trial design of Pfizer/BioNtech was 3 weeks between doses; Moderna was 4 weeks between doses; AztraZeneca was supposed to be 4 weeks but ended up going LONGER (12) in the half dose/full dose group. Indeed, longer interval implicated for more efficacy in
the half dose/full dose group (not the half dose thing). The 3 week/4 week interval in Pfizer/Moderna is not because that led to more immunogenicity but because shortest interval chosen because trials understandably in a HURRY! Lives depended on those trial results.
Extending interval not only likely harmless, could lead to more immunogenicity like in AztraZeneca trial. In terms of "resistance", immune system is not like a bacteria confronting selective drug pressure from a lower dose of an antibiotic. It will respond to the foreign protein
• • •
Missing some Tweet in this thread? You can try to
force a refresh
