New Study Questions Effectiveness of Fourth COVID Vaccine Dose

In this video, the speaker discusses the results of a study conducted in Austria on the effectiveness of a fourth dose of the COVID-19 vaccine. The study found that the fourth dose did not reduce deaths compared to those who received three doses. It also revealed that the vaccine initially reduced infections for three months, but after that, there was a significant increase in infections for the following six months. The researchers raised concerns about the current vaccination policies and suggested a re-evaluation of the risk-benefit ratio. They also highlighted the need to focus on hard clinical outcomes such as deaths when evaluating vaccine effectiveness.

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Key Insights:

  • A population-wide study in Austria found that a fourth dose of COVID vaccine did not reduce deaths compared to those who had only received three doses.
  • In fact, the study found that those who had a fourth dose actually had a slightly higher death rate, although not statistically significant.
  • While the fourth dose did provide a 177% reduction in new infections for the first three months, data from the following six months showed an increase in infections compared to those with less vaccines.
  • There is concern that the increase in infections could be linked to a decrease in overall immune efficiency.
  • The study suggests that the current recommendations for repeated vaccine boosters need to be re-evaluated, especially for individuals with prior COVID infections.


Warm welcome to today’s talk, Wednesday the 13th of December. Now, for the last few days, I’ve been talking to Professor Stefan Pils in Austria about his latest paper, and I’m going to give you the results of that now. Now, what they were looking at was the effect of the fourth dose of a COVID vaccine. Now, of course, we are where we are now with a current level of immunity, with the current variants, and people in the United States, the CDC, for example, advocating strongly that people get these additional booster doses, and a similar situation in the UK for certain specified groups. But is this working well? The data from Austria, to be quite honest, says it’s not. It really puts into doubt the current recommendations from the CDC and the British authorities because what they found was, and this is a population-wide study for basically the whole population of Austria, was that the additional dose of vaccine, the fourth vaccine, conferred no reduction in deaths compared to people who’d only had three vaccines. Now, in fact, the people that had a fourth vaccine did actually have a higher death rate, slightly higher death rate on a very small baseline because not many people, thankfully, are dying. But it wasn’t statistically significant, so the authors have said there was no reduction, no change in deaths. So a fourth dose of vaccine is not protecting against death. So why are we doing it? Does it protect against infection? Well, yes, it does, for the first three months. There was a 177% reduction in the number of new infections. But, and it’s a huge but, for the six months after that, for the six months into 2023 when this data was collected, there were actually more infections. So the vaccine is actually causing no reduction in mortality, and after a small three-month hiatus, for the six months after that, where the data was collected, it’s actually causing more people to become infected. And I would have thought if more people are infected, then there’s a greater risk of long COVID, greater risk of sequelae. So really, what are we doing at the moment? There are significant fundamental questions to be asked here. And also, there was a general trend that they found that people who had more vaccines got more infections overall, and people who had less vaccines got less COVID infections overall. What is going on here? Now, let’s hope that this increase in infections that we’re seeing is due to things like production of immunoglobulin Type 4. Let’s hope it’s due to sensitization of cells like suppressor T cells. I really hope that the increase in the infection that we are seeing is not caused by some overall effect reducing immune efficiency in the body as a whole. Let’s hope that’s not the case. We simply don’t have the data to adjudicate on that at the moment, but really quite significant questions to be asked. Now, let’s go into the detail on this. Do stick around. It is really interesting. Now, this is the paper here, and we notice, for example, that there’s Professor Ian Nois here and Professor Pils. These are some of the world’s leading medical researchers. In this peer-reviewed paper, there we go, it’s from the Journal of the European Journal of Clinical Investigation. Now, this is very readable, surprisingly readable, and the whole paper is made available for free download. For the amount of detailed medical information in it, it’s actually really, really readable. And I would suggest that you download that. If nothing else, downloading it is good for the paper algorithm, so do encourage you to download that. Now, let’s get down to the details straight away. Now, here we have it. This is the paper here. The effectiveness of the fourth SARS-CoV-2 vaccine dose in previously infected adults from Austria. Now, these are people that are previously infected, so we’re dealing with a population group here that are previously infected. Now, we have seen data from the Office for National Statistics in the UK, for example, that shows the amount of SARS-CoV-2 antibody was at some points, I think it was over 99%. So, I think it’s fair to say that pretty well everyone has been exposed and the vast majority of people have been infected. So, we’re dealing with the previously infected population predominantly. So, this data is highly relevant to the current population that we now are. So, that makes perfect sense to me. That’s the link there. Download it for yourself. Now, the authors said that evidence is limited on the effectiveness of the fourth vaccine dose against coronavirus disease. Prior to their paper, you’ve got to really ask the question, why isn’t this research being done in the United States? Why isn’t it being done in the UK? Why is it just being done in Austria and a few other countries? Yeah, interesting question. In populations with prior coronavirus infection, which of course we all now are, they estimated the risk of death, which was the primary outcome, and they also investigated the risk of infection, as we have said. In case of short of time, there was no difference in the amount of deaths. Infections went down for three months and then went dramatically up for six months. So, overall, it looks like it’s actually causing infections for longer, a six-month period, than a three-month period. Now, the method, the methods that were used, it’s a nationwide retrospective observational study, so it covers huge numbers of people in the country. Data was from the 1st of November to the 31st of December, so a two-month period in 2022, although there is a follow-up that we will mention into 2023. Primarily, we’re comparing individuals with four versus three vaccine doses on the whole population. What were the results? They found 3.9 million people previously infected. 71% of those had four vaccine doses, 38% had four vaccine doses, 281,000 and 38% had three vaccine doses. Now, these are huge numbers, 281,000. Very good statistics out of it, but shows a very low background rate of death from COVID, which again puts a question mark over the current vaccination policy, really. So, they recorded 69 deaths on 89,000 infections. So, pretty good numbers on the infections, thankfully very low numbers on the deaths, which is why the data on the deaths was more uncertain. The majority of COVID-19 deaths and a significant portion of all-cause deaths occurred in nursing home residents, sad to see. And of course, nursing home residents typically are inside all the time, often short of vitamin D, factors that we could go on and talk about. There’s no mention of medication or anything like that in the report, so we simply don’t know. Relative vaccine effectiveness, RVE, for four vaccines versus three doses, 24% negative effect against COVID-19 deaths. Now, as we said, this was only based on 69 deaths, so this is not significant, although it may be. We simply don’t know. We don’t have the numbers to say, thankfully. But what the researchers can say with confidence is there is no reduction in deaths as a result of the fourth vaccine dose, that is the second booster dose. 177% protection against infection for three months, but then after three months, for the six months after that, as we said, there were actually a lot more infections. So, the vaccine is supposed to protect against infection rapidly diminished over time, and infection with four vaccines was high during the extended follow-up until June 2023. So, for the six months after this, more infections. So, less infections for three months, followed by more infections for six months. Not a very good trade-off, really, you might think. Now, adjusted hazard ratio for all-cause mortality people that had four vaccines had lower mortality overall, but this is probably what you call the healthy vaccine effect, in that people that took the vaccine were healthier. So, people that were about to die in hospices, for example, you wouldn’t be vaccinating. And obviously, people that already died of COVID-19 can’t die of something else anyway, so healthy vaccine effect. There is probably the main factor that is people with a fourth dose, 79% less likely to die, suggesting healthy vaccine bias. Excuse me, I’ve still got a bit of a cough after my COVID episode last week. Moving on rapidly, what’s the discussion from the authors? In previously infected individuals, a fourth vaccine dose did not reduce the risk of COVID-19 death, but was transiently related with reduction of SARS-CoV-2 infection. But then went up after that, reversal of this effect in the longer follow-up or cause mortality data, suggest a healthy vaccine bias. So the people that were getting vaccine were more healthy. Now, more details. Mostly Pfizer vaccine in this study. The overall case fatality was 0.08%. But if we assume that 10% of infections were picked up, of course, that will give an infection fatality rate much lower. So good to see that they are relatively low. Individuals repeated previous infection had reduced reinfection risk. So in other words, natural immunity was evident. People who had repeated infections did better. And in fact, the authors did say that natural immunity may be the main determinant of immunological protection in a population. So definitely benefits seen from natural acquired immunity. By the end of 2022, the vast majority of the global population already acquired some immune protection. Of course, as we’ve said, this has been around for a long time. And now at the end of 2023, of course, it’s even more so. Compared to three vaccine doses, those with fewer or no vaccine doses did not differ with regard to mortality, no protective effect on mortality, but had a reduced risk of SARS-CoV-2 infection early on in 2022. Infection fatality rate due to SARS-CoV-2 significantly declined, suggesting transition into endemicity, as we know, which, of course, is good. Also, directly from the paper, in general, our study results question whether recommendations for repeated vaccine boosters against SARS-CoV-2 are currently justified for large parts of the general population with a history of previous infections. CDC, take note. Measures against SARS-CoV-2, including vaccine policy, should be critically re-evaluated with the risk-to-benefit ratio. Of course, we are not discussing adverse events of vaccines here, but we know they exist. So, we’re getting the risk of adverse events from the vaccine, known and unknown. We’re not getting any reduction in deaths. We are getting a reduction in infections for three months, but then we’re getting a result, an increase in infections for three months. We don’t know why there’s an increase in infections. We don’t know if this is caused by some problem with the immune system as a whole, or whether this is a specific effect. Either way, I would have thought that might constitute a red flag, but over to the regulatory authorities. As most SARS-CoV-2 infections are asymptomatic or mild in the endemic phase, effectiveness of vaccination should primarily be evaluated against hard clinical outcomes, such as deaths, which they did and found no difference. As we said, the extended follow-up was the first half of 2023, when more infections were seen. Omicron was the predominant variant at that time. During this time, there were 225 deaths, and still, they saw no benefit from a fourth dose of vaccine, even with the high numbers of deaths, no significant effect in saving lives. They saw lots of infections, and we now know from the previous data that infections would have been lower for the first three months, but higher for the next six months, assuming that the 2023 data panned out the same as the 2022 data, which it probably would have done. Analysis in 2023 confirms no relative vaccine effectiveness for four versus three doses in terms of mortality, but shows a higher risk of SARS-CoV-2 infection. 17% actually more for 6 months could have been for longer. What about July, August, September, October, November, December, 2023? The data wasn’t collected. There was a cutoff point to the study, so we don’t know. This is, perhaps, the most concerning thing here, is the some problem that the vaccine is affecting immunity as a whole. I really hope that’s not the case. I hope it’s just a specific effect on immunity against COVID, giving more COVID infections, rather than more infections overall. And of course, things like cancer are determined on the how cancer is maintained at bay by the quality of the immune system. So, a few things that are concerning there, really. So, get hold of the paper. There it is, eminently readable, and really, the authorities need to be asking the question, why are we vaccinating when it doesn’t protect against death from COVID? Why are we vaccinating when, although it might cause reduced infections for three months, it causes greatly more infections after, in the six months following? We’re giving a vaccine that’s increasing the amount of infections it’s supposed to protect against. On that point of incredulity, I will leave you. And thank you for watching, and you’ll see at the end.