In the race to develop vaccines and treatments for COVID-19, there have been some recent obstacles.
On Monday, Johnson & Johnson announced it had halted a large-scale trial of its COVID-19 vaccine candidate. US testing of a vaccine being developed by AstraZeneca is still on hold after that trial was paused last month.
Vaccine developers say these temporary halts show that the trials are being done properly and that such a timeline goes with the territory. The vaccine-skeptical public might view it differently.
For more on what all these pauses mean, The World's host Marco Werman spoke with Polly Roy, a professor and chair of virology at the London School of Hygiene and Tropical Medicine.
Polly Roy: Any vaccine candidates for any vaccine in a large-scale trial will see some people react. It is actually normal and it should show the vaccine is working. And it is good that during the pause they are trying to find out exactly what is the reason [for the apparent illness]. And it could be for any reason. So, it's not necessarily the direct fault of the vaccine itself.
It's the very same issue because they did a large-scale trial also, very carefully, step by step, and very transparent. And exactly the same thing happened. So, I don't find that it is a real issue.
It's totally normal. If you did not have any hiccup, that means your vaccine may not be really that good — it's not really working. It will have a different reaction with different people. The main thing is that the majority of people will not have any reaction.
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You have to convince them of how we got the vaccine to such a good place for smallpox, for example, or yellow fever. Of course, initially, there was a problem in convincing people. But they have to understand these fundamental issues. A vaccine is the key for stopping any infectious disease. And this is the time we can make it a safe vaccine, definitely, because the science is so advanced. And that's the key message everybody should understand. We are transferring knowledge for everybody to understand what's going on, to educate people properly about why we have a vaccine.
If you can explain for each vaccine what danger there could be, then people will understand. Not everybody has to be a scientist, but scientists have to make others understand how each of the vaccines are working and whether they do any harm in the body or not — and whether they have any future effects or not. But the main goal is that all these vaccines are trying to make strong antibodies without too many side effects. That is the idea, but you can address this sort of thing. You have to test with many people.
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What if I say which is my favorite? Because I am very much making vaccines also, I don't want to rush into anything. So, I stay in the background.
Of course. I'm not telling anybody I'm making a vaccine. I'm doing it out of my own interest because I'm a scientist.
Yes, because that's the case for most of the vaccines. Think about the polio vaccine. It's the same way [to the goal]. Because you start with what is the best available at that time. And then you improve with the different designs because they're learning every day. Once they do all these trials, we will know what is happening with side effects and what we should avoid.
This interview has been lightly edited and condensed for clarity.
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