Originally Posted by
rsvman
I don't think this is discouraging at all, and I applaud a person at a company admitting that the vaccine might not walk on water, clean fish, and ball melons.
Vaccines, generally speaking, are designed to protect against ILLNESS, not to protect against INFECTION. Even wild-type infection doesn't usually prevent reinfection; for example, people who had chickenpox when they were little generally don't get chickenpox a second time, but mothers who had chickenpox as children do see a boost in their antibody titers when one of their children gets chickenpox. This is because the mother is getting infected, but not getting sick.
I would posit that not only do we not know whether the Moderna vaccine can prevent spread, we further don't know that it won't. Infections are obviously spread more easily when the virus is allowed to replicate to high titers. Vaccination should probably not allow that to happen, so that even if there is a POTENTIAL for spread, practically speaking it won't be a lot of potential. And if other people are protected from disease by vaccination, even if the virus spreads it won't cause illness. So, to my way of thinking, this is just another reason for as many people as possible to go out and get their vaccination.
Oh, and the Astra-Zeneca vaccine trial did report a reduction in asymptomatic shedding, too, so there is at least some evidence that their vaccine might also prevent spread.
Either way we are in a good place as soon as millions of vaccines become readily available and as soon as we can convince people that getting vaccinated is in their best interest. I know, both are huge "ifs."
I linked this article earlier, but didn't quote this key passage, which says the trials for the Moderna and Pfizer vaccines didn't use frequent testing, but the AstraZeneca trials did, which is an interesting difference:
On the other hand, it is also possible that people who received the vaccine may have been infected with the virus but had only mild or no symptoms, so they might not have been captured in the number of confirmed Covid-19 cases so far. Oxford-AstraZeneca conducted weekly swab tests of volunteers as part of its trial, which may have detected mild infections. But the Moderna trial and the Pfizer-BioNTech trial only reported people who experienced symptoms and were later confirmed to be infected.
“There are likely many more infections than there are disease events, and even more than that, there are many more exposures,” Janes said. “We will ultimately capture the infections that accrue in the trial, but it will be a while longer before we know anything about those.”
I agree that most of us shouldn't get too worried about this, unless we are in close contact with someone who can't mount an effective immune response. But it is something to keep in mind as people start getting vaccinated. Just because someone has been vaccinated doesn't mean they can't spread the coronavirus.
https://www.vox.com/21575420/oxford-...zeneca-results