Episode #30 - Vaccines-when and why?

VGS   Hello and welcome to Science in 5, WHO's conversation in science. I'm Vismita Gupta-Smith, and today we are continuing with our conversation about vaccines. Answering some of your concerns is WHO's chief scientist, Dr. Soumya Swaminathan. Welcome, Soumya.

SS   Hello, Vismita.

VGS   So Soumya, one of the questions we get often is when am I getting my vaccine?

SS   What we need to understand is that the vaccine development and manufacturing process is very complex. The fact that we have, you know, 8 to 10 vaccines now that are currently being used at scale itself is a huge achievement. Now to manufacture 12 to 14 billion doses to cover the entire world's population - that is a challenge. So this is where we can do some things to help. Firstly, there are a lot of raw ingredients that go into vaccines that are sourced from different places in the world.

Now, we need to make sure that there is a free flow of these ingredients happening between countries, that there are no export bans and other impediments to these global supply chains. That's the first thing. The second is we can encourage companies, which have the capacity to manufacture, which have the bulk product, to explore with companies which might have some spare capacity to do what is called "fill and finish" where you take the bulk product and then you put it into vials. And the third approach, which may take a little bit longer, but it's really looking ahead to the future, is about improving the capacity, increasing capacity to produce vaccines in all parts of the world by technology transfer.

VGS   Soumya, the other question we hear often is that since we are still gathering evidence about how long immunity will last from vaccines and there are so many variants now, why should I get vaccinated now? Why shouldn't I wait?

SS   Yes, you're right. We are learning something every day . We're also learning from all the different clinical trials of the vaccines that have been undertaken, especially the vaccines that are now approved for use, as well as from the rollouts that countries are doing in their populations and they are actually studying the impact that these vaccines are having on their populations.

And so what we've seen so far is that the majority of the vaccines are extremely effective at preventing severe disease, hospitalization and death. And that's true across all of the vaccines that have been studied so far. So that is really important. And that's what we want. We must also remember that the more people get vaccinated and build up their immunity against the virus, the less the chances of the virus replicating, growing, increasing and spreading from person to person and thereby we're actually reducing the chances of more mutations and more variants.

VGS   The question that is being asked and we hear most is: what about these side effects? I'm hearing about side effects and it's concerning me. What can you tell us about that?

SS   There are always some risks associated with any drug or vaccine. Nothing is 100% percent safe. But the risk may be that one in a million people get a certain complication, particularly if they are already prone to it, or one in a million people get a severe allergic reaction to the vaccine. Now, these are risks that if you understand, you can anticipate and you can inform people and you can prevent that from becoming a problem. There is a huge effort being put into collecting the adverse effects or the side effects of these vaccines.

So what we need to see is, is the vaccine linked in any way to this event? And so you need to very carefully look into the individual cases and try to find whether there's a link. Is there a scientific explanation for the vaccine and its ingredients and what we are seeing happen? And is that a difference in the rates of these events between those who are vaccinated and what would occur in the general population anyway. And by looking at this data very carefully, groups of scientists and experts come to the conclusion of whether a particular product is safe or unsafe.

And if at all, we find anything that's of concern with any of the vaccines, we will put out an advisory so that governments can then take action, depending on on what needs to be done.

VGS   Thank you Soumya. There you have it. That was Science in five today. Don't forget to share and subscribe to our social media channels so that you are the source of evidence based scientific information. Until next time, then stay healthy, stay safe and stick with science.