Ask a Specialist: COVID-19 Vaccine with Prof. Sibrandes Poppema (Part 1)
11:33PM Jun 7, +0000
Speakers:
Raihan Rahman
PC Gan
Prof. Sibrandes Poppema
Keywords:
vaccine
astrazeneca
vaccinated
people
virus
immune response
antibodies
dose
clotting
called
professor
question
doses
instance
malaysia
infected
protection
clinical trials
herd immunity
coagulation
Hi and welcome to another episode of the live Homage Web Series. Thank you for joining us in this session and today we'll be talking to Professor Sibrandes Poppema. Professor Poppema is currently the President of Sunway University and Advisor to the Chancellor. Previously, he was also the president of the University of Groningen, a global top 100 University. He is also a specialist in Immunopathology, and is in the top 2% of the most cited authors in the world in the field of Immunology. Today, he's here to discuss the science of vaccines, her d immunity and answering some lingering questions regarding the COVID-19 vaccine. So without further ado, let's hear from our anchor PC Gan and our very esteemed guest, Professor Poppema.
Good morning, selamat.
Hello, Professor, thank you so much for taking the time and speaking to us. So I think for the general viewers out there, thank you for tuning in. We also want to let you know that this health information is provided for general information, and this video only representative speakers view on COVID-19, and its vaccine. Okay, so without further ado let's jump quickly straight to the first question, right. Professor if you can just let us know what does vaccine means, and if it means 100% protection.
Yes, that's, that's a good question or both are good questions.
A vaccine, is basically anything that is mimicking the real virus in case of a viral infection, and that is intended to produce an immune response, just like the immune response that would happen when you would be infected. And of course the idea is that when you have been vaccinated, the immune response would already be there at the moment where you would get infected. So it would protect against the actual infection. So it's called vaccine. After a Latin word Vacca, which is the word for cow. And the reason for that is, is that the first vaccinations that were being done, were somewhere in the 18th century about around 1794 or so where people were using parts of a cow pox to vaccinate, particularly children for smallpox. So that's where the word vaccine come from, and it's a very typical example because they would take weakened, a weakened virus the cow pox virus would be similar to the human virus but in humans, much weaker. Now, if we look at COVID, and we look at a different vaccines, we may all remember that a year ago when people started to talk about this vaccine that we said, oh, this will take a long time. This may take up to five years you know that the best results we ever have of getting a new vaccine but after five years. And what we know now is that we had a whole range of different vaccines, after one year. And that is really a great achievement by science, and the types of vaccines that have been made range from traditional to very novel approaches. The traditional approach is the one that for instance Sinovac has been using. And that's the approach where you take the virus, grow up the virus, and then denature. In other words, deactivate a virus, and use that to vaccinate somebody. So you inject the virus but the virus is dead, the virus cannot increase in number, but the immune response will happen. So then when next time when you meet the real virus you already have immunity.
There's other examples for instance the AstraZeneca vaccine is an example of where they've been using a different virus, and adenovirus that can give you some cold symptoms, but is not very dangerous for people, and then they put a little bit of the DNA of the coronavirus in there. And that little bit of DNA is coding for one of the proteins of the Coronavirus and particularly for that part of the Coronavirus that makes the cells, enter that makes the virus into human cells. So that's another approach. And then there is the third major approach, There's many different ones but the third major approach which was using messenger RNA. So those are the vaccines of Pfizer and Moderna. So a year ago, we had no idea what would work best. We knew that the traditional one, The one that Sinovac is using probably would work, because that's done many times, the one with the adenovirus had been used a few times had been used for Ebola virus, for instance, we knew it was active there but whether it would work here, we didn't know. And finally, the messenger RNA one. We were not sure at all, because that one had been developed over a number of years so people think it was very quick that's not quite true. People have been working on this technology for about 20 years. And the idea was to make vaccines for cancer. But once the Coronavirus came around the scientist got very quickly the idea that this might also work for this so they started working on this micro RNA on this messenger RNA. And when these messenger RNA does is it's entering our own cells, and then makes our cells produce the viral protein again, and then the immune response will appear. So in all cases, the idea is that our body will make an immune response against the virus or parts of the virus.
Is it 100% protective? Ideally, yes, but it's not the case. So basically you can take that in two different parts is one, will it protect everybody who is vaccinated. And the answer is no, even the best example. So the Pfizer vaccine is protecting for about 90 to 95%. So there's still 5%-8% of the people that do not have protection, and also when we talk about the protection itself. It's not the same in everybody. So in some it will protect so they will not even get infected. You know that's ideal. But in general, what it does is that it makes sure that people that otherwise would have gotten very sick might have even died or ended up in intensive care or on the ventilator or ended up in hospital are only very mildly sick and you know that's the main goal is to make sure that the infection is not as serious as it otherwise would have been. And the reason that that is happening is that the vaccine has made that already you have an immune response, and the immune response is in two parts. So, we are reading a lot about the antibodies and people are being worried whether the antibodies are still there after half a year or one year or whatever, but the antibodies is just one part of the immune response. The most important part, in fact, is what's called the cellular immune response which are the T lymphocytes, which recognize the viral proteins and next help other lymphocytes the so called B lymphocytes to make these antibodies. So the antibodies are important because the best ones are those, the so called neutralising antibodies can actually make sure that the virus is not even entering our cells, but the cellular immune response also makes sure that when cells are infected those cells are being killed, etc. So, what we know is that in the vast majority of people, there is a good cellular immune response, and also that cellular immune response stays around for a very long time. So when in time we will meet a virus, again, the immune response can be ramped up very quickly, and then help the B cells to produce new antibodies and take care of this infection. So that's really the goal.
Okay, well I have so many questions in my mind right now, so maybe the first one that's right on top is that so while my body is still trying to produce the antibody. That means that there's still a chance that I can contract the COVID-19 virus, and I can still be a carrier?
Yeah carrier is maybe not the right word, but basically yes you can still be infected. And the reason for that is, is that when somebody's breathing the virus in the air, and you breathe it in. Of course you are still infected, and the virus may still be present in your nose or in your throat, and if that is the case, you may still breathe it out. It's much much much reduced in comparison to somebody who is not vaccinated, but it is still possible. That also is why we require people that have been vaccinated. At this time, when only few people have been vaccinated, to still wear a face mask so they cannot infect other people if they will become infected themselves. So that's why we are still very careful. The thing is that although you may be infected. You will not get seriously sick anymore, because you have the immune response that will keep the virus in check in your body.
Okay, got it. So then Professor is there a difference between some vaccine who has got only one dose and dose that have two doses, and does that mean that the ones with two doses, is, you need, is less potent than the one with one dose?
Yeah, that's, that's, that's, again, an interesting question. So basically, let's talk about these three types. The ones that are. So the denatured virus, the Sinovac for instance, in general, what we do in Immunology, is you immunise, And it takes about seven or eight days before this, an immune response that will produce antibodies. And then we know that when we wait for about two weeks, or you can also wait somewhat longer, and we give it again, that the immune response will become much stronger. So that's called a booster, it makes the immune response, much stronger. The second time around. So basically, for most of these, the case is that after one doses, you know the protection would be let's say 30% or 50%, and after the second one, it would go up to 70 or 80% So that's why it's done that way. The, the two exceptions are the Johnson & Johnson and Johnson one and the one of I think it's Sinofarm, one of the Chinese ones, which are one dose. What they have in common is that both of those have been produced by the adenovirus technology where they put DNA of the Coronavirus into the vaccine and into the adenovirus and it may be that, in that situation, the adenovirus stays around for somewhat longer time in the individual. And so the immune response is also for a longer period. That may be why there's a difference between those, in general, a two dose regimen is the normal approach, because that second boost will really help and the third boost would probably even help more. The one, the one shot is really helpful, particularly when you are dealing with people that are difficult to reach, where you are not sure they would show up for a second dose, etc. So particularly for such groups of people, it's very interesting to have this one dose regimen. It's not like that one dose regimen is better than the other ones.
Okay, got it. So Professor I'm the type of person, if let's say I'm unwell and if the doctor were to prescribe. Okay, you need to have this three times a day, I will make sure that I'll take 24 hours divided into three. So, same thing with this vaccine right. The recommended duration between the first dose and the second dose is about 12 weeks. Now what if I mean, you know, given that, right now, things are so chaotic. What if it's not done within this recommended period, and if it's much longer see maybe, example, four months to six months later, what will this mean to my body?
Yeah, another question where perhaps we may not even have the full answer. Why do we say normally two weeks because initially it's two weeks is because we know that when we give a boost after two weeks it will really work well. What we also know is that if we wait somewhat longer six weeks, 10 weeks, 12 weeks. It also works very well. And in fact, it's been shown that after 12 weeks, the level of the antibodies would be higher than with a boost after two weeks, so 12 weeks is good, why don't we say, longer because it's really not been tested, so we don't have the answer it's quite possible that it would work well as well, but we simply don't know. But there's another side to this coin, you know most coins have two sides, and this one also has two sides. So, the side of the coin that's that's good for a longer period, let's say 12 weeks instead of two weeks, is that one, We can immunise more people, a first time, and give them some protection. So that's good. The second thing is that when you do it later, the amount of antibody, generally, is somewhat higher than when you do it earlier, so that's, you know, the two good sides of this coin. The downsides of waiting is that it's been shown that when you have only one dose. Your protection for instance again some of the variants, the South African variant for instance, is not very good yet so it's maybe only 33% protection. And then you really would not want to wait till 12 weeks because those 12 weeks, you would still run as severe risk of contracting the South African variant. So basically that's why it's better to stick to the three weeks as we are doing in Malaysia now rather than doing longer periods. So it's these two sides and both have to be taken into account, but since we now also have the South African variant in Malaysia. It is better to keep the period between the first and the second short shot to about three weeks.
Okay, so I guess maybe because I'm a little bit more worried because I think there are a lot of people were saying that I can't even get my first appointment so I , me being the first batch that's being vaccinated, I'm also a bit worried like: Will I even get my second dose before we reach the herd immunity, so maybe then the next question that I have is does herd immunity means everyone getting at least the first dose, or is it the second dose, Or what is herd immunity?
Yeah, well herd again, coming from cows, right. So, this is also going back a long time, where people noticed that, you know, when you had a herd of cows, where many had already had the disease that they would be more protected than when you had a herd where no one had had the disease. So here also herd immunity can be achieved in two different ways one is a herd of people that had the disease and survived. And when it would be enough, this would be called herd immunity, that's not an option in COVID Because way too many people would die to be acceptable. So that's why, in, in, in all countries, basically, the government has said no we have to avoid that you know we cannot just let the virus go, we have to have all sorts of protection. The second way to achieve herd immunity of course is through vaccination. And we need to achieve both doses of the vaccine in 70, 75-80% of the population so why am I giving a range that also has to do with which variants we have how infective these variants are, you know, there's the original virus then there's now they've got a new name so now they got two Greek letters, but originally you know we call the the UK one which is now alpha and the South African one which is now beta, and the Brazilian one which is now gamma and so on. So, but basically, If they are more infected, we will need a higher proportion of people that are fully vaccinated, and the herd immunity only comes after the second dose. So we need to have sufficient people that have had both doses.
Okay, got it. So maybe for the audience, if you have any questions, please put in the chat, so that we can address them. So that Professor can address them. So, while we wait for the questions to come in Professor I have one more question. So because there are two doses, and I personally took AstraZeneca. I think at one point of time KJ mentioned that we can actually choose which vaccine we want. So does that mean that. Or rather, is it okay for me to choose another vaccine, if I have really taken the first one with AstraZeneca and second one with. I don't know, maybe Sinovac?
The thing is that, theoretically, it's fine. I'm a scientist. So the problem for me is to say that many of the things have not been tested, you know, when we start out with a new vaccine. We go through all of these clinical trials for safety for efficacy and so on, we want to do certain numbers we want to know how it goes exactly for this. Theoretically, it would work fine, because basically what you do is you get the first, first vaccine, the immune response is against the virus, you would get another one. And, and you would get a response, maybe against a little bit different part of the riders and theoretically this should work well. The problem is no real trials have been done with these combination. So I would advise people to take the same one, because that's scientifically proven. If there are good reasons why somebody should not take the second dose of one type, let's say somebody would have shown a strong response, or an allergic response against, for instance the AstraZeneca, it would be safe enough to take, let's say Pfizer for the second one, that would not be a big problem, but the thing is that doctors don't really like to do it, because it's not a scientifically proven combination.
And I suppose. Also it's because it's tested in different environments have different ways of testing so to have two different types of vaccine in the body, it. Yeah, so it's not actually proven how the body would react if it's two different vaccine I suppose
It simply, you know the experiments have not been done. As I said, theoretically it should work fine. But for medicine we are used to doing a trial and making sure it's fine.
Okay, sure. So, we have got a question here. I suppose we are, we there's just so many information out there on the internet. We've heard about the blood clot we have heard about, actually we have not heard about any side effects for the other vaccine so I suppose this this question here on does the brand really matter.
To be honest, not really. I think that all the vaccines that have been approved in Malaysia, and have been approved by WHO, which are you know the Moderna, and the Pfizer and the AstraZeneca and the Johnson and Johnson and Sinovac and Sinopharm and so on, all have been shown to be effective, and to be safe. So those are the two important things. And yes, there have been some side effects, particularly was AstraZeneca but also with Johnson and Johnson. They are extremely infrequent. And if you compare the risk of Coronavirus infection, with the risk of this, there is such a big advantage in taking the vaccine that you really have to say that any vaccine is good right now. There is some hesitancy in young women, particularly with AstraZeneca, and many companies have decided not to use AstraZeneca in young women. But again, even in that group, you know, it's your chances of winning the lottery, are much better than the risk of getting those side effects.
But on the topic of women who are, I think, expecting and also breastfeeding I think we have also been getting different messages. I think at one point of time, it was mentioned that it's not okay to take AstraZeneca and then suddenly there's a turn around to say that it's okay, what's your opinion, Professor?
Yeah. Okay, so the thing with both pregnancy and breastfeeding, actually, is that why was it initially not advised quite simple, because the experiment had not been done. So there were no clinical trials looking in women that were pregnant, and no clinical trials and women that were breastfeeding. In the meantime, sufficient people have been vaccinated that were pregnant, knowing it or not knowing it, or were breastfeeding, and it is quite clear that there is no risk in pregnancy, and in fact that when you look at breastfeeding there's probably even an advantage. And the advantage is that the woman who is vaccinated while breastfeeding will produce antibodies that also will get into the milk and in a way, give what's called passive immunity to the child. So the child actually will be protected, also against the virus through the antibodies that the mother is producing. So, it's in fact, an advantage.
Okay. Yeah, it makes sense, it makes sense Professor. We have got another question. Is vaccine, AstraZeneca vaccine suitable for young people between 18 to 25 years? If I'm not mistaken UK use Pfizer for young people, instead of AstraZeneca.
Yeah, this all has to do with these findings in particularly some European countries that particularly younger women but younger is not just 18 to 25 but, you know would be also up to let's say 50 or so that they had a higher risk of developing this very unusual coaguation disease that when you look at older people, or you look at males, it's not a black and white difference, but the frequency is higher, it's still quite infrequent, so many countries are erring on the side of safety, and now not giving AstraZeneca to young people, they provide them with a different alternative, you know, in many cases, but I still believe that is much better to become vaccinated. Also to become vaccinated with AstraZeneca, than not getting a vaccine.
Yeah, yeah. Okay this one is interesting because I've read quite a bit about efficacy rates so maybe before we answer that question, Professor if you can help us understand what is the meaning of efficacy rate. And why is it different with the different vaccines out there.
Yeah, the efficacy rate basically is how well it works you know to make it quite simple, and the different vaccines. I tried to explain earlier that it is, of course, dependent on the vaccine, but it's also dependent on the situation, where you test the vaccine. So if you take a vaccine in the clinical trial and you take it in an environment in which there's a very high load of virus so this example of the clinical trial in Brazil, among healthcare workers during a tremendous epidemic in, In Brazil, so they were exposed to loads of doses, loads of virus, every day, and then the protection then was 50% in other words, 50% of them still were not necessarily getting sick, but they became positive, because they were exposed to the virus. So in that situation that's the most difficult situation in which you can test the virus, and test the vaccine. And then the result may like like that, if you test in a population where very few people are sick, you will find also that the protection is much higher, because the people are not exposed to the vaccinated people are not exposed to so much and not to such high doses of drivers. So that is one reason why in the clinical trials, there are some differences so for instance this difference between 50% in Brazil 80% protection was the same, same vaccine in Turkey. It all had to do with how much exposure, the vaccinated people have. So that's, that's one thing. The other thing that's very, very important concept is that there's a difference between what you see in a clinical trial, and real life experience, and real life experience actually is the most important thing. And so to still take the same cinovec vaccine in a small town in Brazil, near Sao Paulo, and a small town named Serrana. They've done an experiment, one can call it so they vaccinated, all adults in this town of 46,000 people with the Sinovac vaccine and what it showed was that the protection, not just for the people that had been vaccinated, but for the whole population, so including the children that have not been vaccinated, was 95%. So they have achieved herd immunity. And when you have herd immunity. That's the idea of herd immunity, you're not only protecting yourself, but you're also protecting others. So, a vaccine. And this was in the period in which the number of infections in Brazil were very high so in Sao Paolo, things went very bad. Whereas in Serrana, where they had been vaccinated, they were protected. So this real life efficacy, showing that when sufficient people are vaccinated. This protection for the vaccinated, but also for the people that are not are not yet vaccinated, so in that case children, for instance.
Wow, so in such a big country, or like a vast country like ours example even Indonesia to reach to that herd immunity it's so difficult. I suppose it's you, we can only go by state or by town and slowly spread outwards, I guess.
Well, I think Malaysia right now. So, I think we had about one dose. Yeah, it's always important to know how many wonders how many two doses, but I think we have about 3 million people that at least had one dose. Now, what's important is that now the vaccination efforts is ramping up quite rapidly. So I think that the time is near where Malaysia will be able to do. You know, 1 million vaccinations per week. When we can do 1 million vaccinations per week. I think when we look at a population that's 18 or older, that will be of the 32 million or so Malaysians. I think this, at least 10% that are under 18. So you deduct those. So maybe we need to vaccinate 28 million people. So that would mean that. By October, or something like that, Malaysia, could have achieved. You know, a 70 to 80%, vaccination, you know, two doses spread, so I think. And that's what the government is aiming for. Now initially the aim was to have that done by February next year. Now we wish to have that done, somewhere in October, and I think that really would be very, very good. Now what was holding us back. It was not not willing, it was the difficulty of obtaining sufficient doses of vaccine, you know, because the first condition is, can you buy the vaccine? And that was very difficult because some countries, you know, and I'm sorry to say European countries, American country. They were basically hoarding vaccine. So they bought way too much vaccine for their own, which they are not all going to use you know I think Canada have three times as many vaccines reserved than they actually would need, so they could have given six shot to every Canadian that did not make any sense so now it's possible it's been shown possible also for Malaysia to buy enough of the vaccine, from different sources. So from Pfizer from AstraZeneca from Sinovac and so on. And so for the next month. Malaysia will have sufficient vaccines to go much quicker. It's already happening. Now you know some days now. Around 100,000 people already have been vaccinated per day and it's going up. And I think once we get to about a million per week we will be really doing well.
I think there's, despite the increasing number of cases, I think there's also that hope that we can race towards getting majority of Malaysians vaccinated, I think we all just need to be educated and be equipped with all this information. Thank you, Professor. The next question that we have here is, AstraZeneca safe for smokers. As the blood clot forming is more prominent in these groups of people.
Yeah. Interesting question. What is important is to know that the coagulation that is happening with the AstraZeneca vaccine is a very unusual type of coagulation of blood clotting. Totally different from the types of blood clotting that you see normally. So in fact, there is no relation between the type of blood clotting that you would see, and somebody who is smoking, which the type of blood clotting that you would see in somebody with the AstraZeneca vaccine. So there is no increased risk for them. What is known, of course, is that the risk. In general, is higher. That's true, but it's not increased by this, by AstraZeneca vaccine, because it's a different mechanism. The coagulation, with the AstraZeneca vaccine is a very unusual one because it is leading to the production of antibodies against platelets, and platelets are the, you know small blood cells that will lead the clotting and and when the antibodies bind to it. Then you get this clotting mechanism, and you get this very unusual situation where it seems like you have too few platelets, and still you have lots of clotting. And that's happening because of these antibodies. So that's a very different mechanism from other types of coagulation, that also is for instance why Heparin, which is, is generally used when you have a clotting disease is not working in this type of AstraZeneca, coagulation. No, short answer is, it's safe for smokers.
Or maybe they shouldnt be smoking
It's not safe to smoke though
Exactly my point too, maybe should just stop smoking altogether. Okay. The next question we have here are some people get side effects, but some others do not. How will we know if these vaccines are actually working.
Yes. Good question. Of course, the side effects, indeed, are a good indication so when you talk about the side effects of, like, you know, getting a bit of fever or a headache or feeling like you have a flu, etc, stiffness, it's a good indication that there's an immune response. But from the clinical trials that were carefully controlled we know that also the people that did not get the symptoms, still get a good immune response are still producing antibodies and so on. So, when you have the side effects, rejoice, because you know it's working well, when you don't have them, don't worry, Because we know you still get an immune response.
I suppose this question also pops up because there were also videos showing that they do not get that 0.5 though so I guess people are also worried, like, oh, how come I don't have side effects, And, yeah, you know, mind games.
I know. Okay, let me say the following that. So if you don't have side effects, it does not mean you did not, you know, as I said, you did not get a good response because you might have a good immune response. The story about not getting the full dose, in fact, is not so terribly, terribly important the dose we are getting is not like, you know, a black or white difference between whether it will be point, point, five or point four, you know, in both situations, you would get still a good immune response. Of course, the idea is to get a full dose. And I know that the concern came because people have to get a certain amount of doses out of one bottle sometimes, and then you know the last one, theoretically might be somewhat small, etc. But even if it's a little bit less, don't worry, it still will give you a good protection. It's a standardised dose for all people, you know small people big people, etc. And still, we use this one standardised dose, so it's, it's, it's more than sufficient for everyone.
That's very assuring Professor, thank you so much. Okay, the next one. If this individual had history of anaphylactic reaction towards bird's nest. Is it advisable to take AstraZeneca vaccine, or other vaccine.
No the only situation in which you should not take AstraZeneca vaccine or any vaccine, because this is really not has nothing to do with AstraZeneca vaccine, but has to do with any vaccine, the only reasons to not take it is when people had a serious reaction to a previous vaccination. So if you had another vaccinations for influenza, or you know, for whatever, or when you had another medicine injection, and you had a serious reaction against that, that's when you should not take the vaccine, but first look at you know which vaccine, did you have previously what were the ingredients in that vaccine, what are the ingredients in the AstraZeneca vaccine or in the Pfizer vaccine, and make that compare. So then you really have to go to the doctor and you know make sure that that comparison is being made. But that's the only situation. There's no other allergies food allergies and so on, are really not a problem.