The FDA panel voted unanimously to authorize the J&J vaccine. Good. Note, however, that the single-shot J&J vaccine is quite comparable to the first dose of the Pfizer and Moderna vaccines. Yet, few people are demanding that J&J be required to offer a second shot at all, let alone in 3-4 weeks (What about vaccine escape! How long does immunity with a single-shot last! What about the children!). It really is scandalous how these objections to a single-shot have disappeared. This is evidence of what I call magical thinking–an undue focus on the clinical trial design as having incantatory power.
Why did J&J focus on a single-shot? Was this because of “the science”, i.e. something unique about their vaccine? No. J&J focused on a single-shot vaccine for the same pragmatic reasons that I favor First Doses First.
J&J representatives said they chose to begin with the single shot because the World Health Organization and other experts agreed it would be a faster, more effective tool in an emergency. (emphasis added).
My view is that it would be good if the J&J vaccine was followed by a booster–perhaps of some other vaccine–but that it’s individually fine and in fact socially beneficial to get more people protected quickly by delaying the booster for at least 12 weeks to when vaccines are less scarce. I don’t currently see a reason for thinking differently about the Pfizer and Moderna vaccines.