The Impact of the COVID-19 Vaccine on Spread of Disease
Paul A. Offit, MD, comments on spread of the COVID-19 virus in children who are vaccinated.
William J. Muller, MD, PhD: We went through some of the arguments in favor of vaccinating children, the most important one being that even though the risk is low, it’s not zero, and that it’s important for protecting themselves. I don’t know that there’s necessarily a lot of data on this, but it certainly seems to be rational to consider that these vaccines may also decrease the risk of spread. Was there any discussion of that at the review committee meeting or any data presented at the review committee meeting, that discussed whether or not we can start to get some information on whether or not we can also decrease the spread of disease within the population?
Paul A. Offit, MD: It’s a short incubation period, respiratory mucosal virus, so it’s really hard for a vaccine to dramatically reduce, say spread associated or shedding associated with asymptomatic infection. That’s a lot to ask it. For the longer incubation period diseases, like measles, smallpox, German measles, that’s much more doable than it is here. Hence, there are studies that clearly have been done that have shown in an adult population that if you look at somebody, for example, who was vaccinated, who has mild disease, and compared with someone who wasn’t vaccinated, who has mild disease, and then you do the right kind of study, which is you don’t do antigen detection, you don’t do a PCR, you do infectious virus titers. And, when you do that, you see that those who were vaccinated do shed far less virus for a shorter period of time. Thus, I think they are less contagious, but that you’d still be contagious even though you’re vaccinated. I think, even if the entire world were vaccinated, you would still have spread of this virus, and you will still have mild disease, and that’s something we’re going to eventually have to get used to.
William J. Muller, MD, PhD: I think that’s the expectation. And I think that’s what a lot of people are, hopefully, understanding that, the bar for efficacy depends on what you’re using to define as efficacy. If we’re trying to keep people out of the hospital, these vaccines are very good at that. If we’re trying to keep people from getting severe disease and dying, these vaccines are very good at that. We’re trying to keep people from getting an infection whatsoever, even asymptomatic infection, that’s really, I think a very difficult requests to make of any medical intervention, particularly a vaccine. Thus, in the in-between space, there might be some variability, but that’s maybe not the goal that we’re trying to achieve here. Maybe the goal we’re trying to achieve here is to decrease the amount of disease in the community, so that we can allow more normal life to go on.
Paul A Offit, MD: And I think probably the best current example of where we are in this pandemic is Dr Anthony Fauci. Dr Fauci now has a mildly symptomatic COVID-19 infection. He’s been vaccinated 4 times. But what happens is, is that it’s very hard, especially with these Omicron subvariants to have protection against mildly, so he’s a mild illness, that’s a win. Here’s a man who’s in his 80s, who certainly had high risk of severe disease, who doesn’t have severe disease, because he’s been vaccinated. That’s the future, that’s what you want; you want to protect those who are most vulnerable, in his case, the elderly, from getting severe disease, and that’s a vaccine that’s working well. The media often doesn’t carry it that way, but that is the vaccine that’s working well.
Transcript Edited for Clarity
Study shows dengue vaccine is safe and effective
October 11th 2024Overall, 2 doses of TAK-003 successfully induced the production of neutralizing antibodies against all 4 dengue serotypes in at least 90% of adults, children, and adolescents, regardless of whether they were seronegative or seropositive at baseline.
