With hundreds of millions of people now vaccinated against COVID-19, the coronavirus outbreak should begin to die down in places where a large chunk of the population has been inoculated. But that isn’t happening everywhere.
Instead, two paths are emerging: In countries such as Israel, new COVID-19 cases are declining as vaccinations spread, while in other places like the Seychelles — which has fully inoculated more of its population than any other nation — infections continue to increase or even reach new highs.
One reason for that may be the different types of vaccine being used. Evidence derived from the expanding global inoculation rollout indicates that the messenger RNA shots developed by Moderna Inc. or Pfizer Inc. and BioNTech SE are better at stopping people from becoming contagious, helping reduce onward transmission — an unexpected extra benefit as the first wave of COVID-19 vaccines were intended to stop people from becoming very sick.