For the sake of argument, let’s assume that the effectiveness of j&j and moderna/pfizer are 66% vs 95%, respectively, and this effectiveness comes in at the same time.
I think it’s important to also point out that this assumption is not true. All of these vaccines seem to have similar effectiveness for the first 3 weeks after the first dose and the major divergence happens after the second dose (and I suspect there would be a smaller divergence if we did two doses of J&J, but of course we have “no evidence” of that).
From a wanting-to-end-the-pandemic-faster perspective, my preferred solution is to get one dose of J&J now and a second dose of something else* once we inevitably “discover” that vaccine boosters work in cases that weren’t specifically studied too.
I suspect a second dose of a non-adenovirus vaccine would be more effective than a second dose of an adenovirus-based vaccine due to the risk of adenovirus immunity.
I think it’s important to also point out that this assumption is not true. All of these vaccines seem to have similar effectiveness for the first 3 weeks after the first dose and the major divergence happens after the second dose (and I suspect there would be a smaller divergence if we did two doses of J&J, but of course we have “no evidence” of that).
From a wanting-to-end-the-pandemic-faster perspective, my preferred solution is to get one dose of J&J now and a second dose of something else* once we inevitably “discover” that vaccine boosters work in cases that weren’t specifically studied too.
I suspect a second dose of a non-adenovirus vaccine would be more effective than a second dose of an adenovirus-based vaccine due to the risk of adenovirus immunity.
There is also a risk of PEG immunity which will make one immune to lipid nanoparticle vaccine.