From the article (and presumably from the data in the peer reviewed study), the vaccine is 92% effective at preventing confirmed infection of its recipients starting 7 days after the second dose, with lower effectiveness at prior times. For instance 60% during the time between doses. So, short answer: yes, the vaccine does appear to be effective at reducing transmission of the virus and not just effective at preventing illness or death from it.
Sorry, I quoted the wrong number for the time between doses; it’s 47% effective with one dose, not 60%.
Thanks. I see that but its worded funny. “preventing 92% of confirmed infections”. Usually these things are worded differently, such as “reduced risk of” or in the case of therapeutics for other ailment “improved in X% of patients who received”. Preventing confirmed infections, in my mind anyway, sounds like a rhetorical device.
I think the important question is: Does it prevent those who get the vaccine from spreading it to others? Confirmed infection doesn’t necessarily mean no infection, could just mean very low (unconfirmed/undetectable) viral load. Which is good of course, but not necessarily what we are looking for during this period of roll-out as it will take many many months or even the whole of 2021 before everyone who wants the vaccine to be able to get it.