The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is a novel betacoronavirus that likely emerged late last year from an animal reservoir in China. There is little to no pre-existing immunity against it in the human population. The clinical picture for the disease it causes, coronavirus disease 2019 (COVID-19), ranges from very mild to fatal. The virus is highly transmissible and has spread globally.
While the development of a vaccine is critical for its successful administration at scale, just as critical is the creation and execution of infrastructure necessary for widescale vaccination to greater than 1 billion people.
The WHO defines vaccine efficacy as follows:
Vaccine efficacy: % reduction in disease incidence in a vaccinated group compared to an unvaccinated group under optimal conditions
When will 1bn people have been vaccinated with any vaccine candidate(s) that have demonstrated an efficacy rate >60% in a n>500 RCT?
This question resolves as the date when the first credible article is published that presents the claim that at least 1 billion people have been administered vaccines that had been shown to have an efficacy rate exceeding 60% in a randomized controlled trial with at least 500 participants. This may all be from the same vaccine, for from multiple vaccines. A vaccine is considered "administered" to a person if they receive all the doses as prescribed.
If this does not resolve before 31 December 2023, it resolves as >31 December 2023.
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