Professor open: there are still unknowns about the COVID-19 vaccine, but it is already clear for whom it will not be suitable

Although the official launch of the Pfizer-BioNTech vaccine in Europe is announced on December 27, the researcher prof. Aurelija Žvirblienė affirms that this date is even more symbolic.

He noted that vaccine volumes are very small so far, so most of the population will not be vaccinated right away.

“The quantity of vaccine will be more symbolic at the beginning. However, I think it might be a good idea to start with such small quantities, because it will be possible to verify how the system works, both for the transport of vaccines and for vaccines, how it will be necessary invite people.

The complex vaccine logistics required to ensure an extremely low cold chain must be taken into account. That is, if 100 thousand fall at a time. it would be really difficult, “he said.

The researcher pointed out that the multidose vaccine is also a great challenge, so it will be necessary to vaccinate 5 people from one vial.

We spoke with A. Žvirblienė, professor and immunologist at the VU Life Sciences Center, about how the new vaccine works, if it is safe, and who will be suitable to vaccinate.

Professor, tell me, when is it realistic to get vaccinated for most of society?

I think it would be a good scenario if an important part of society had already been vaccinated for the next fall season, when the risk of new waves and outbreaks of infection will be greater again. Because now there are two more things that are likely to stop the spread of the virus. What we have already seen and what scientists recognize is that this virus is characterized by seasonality. Consequently, the number of cases should start to decrease from March to April.

Another thing, when there are such a large number of infected people at the moment, it can also be a significant part of the people who have gotten sick. That, of course, should definitely be verified, a population survey conducted again. Some companies with outbreaks already follow this practice. You also save by modeling the relevant flows of workers.

You have noticed that traditionally developed and proven vaccines are long overdue and innovative ones that have yet to be tested are appearing faster. Allergic reactions to vaccines have already been announced, will they really be safe for everyone?

Naturally, there are many questions about these vaccines, as this type of RNA vaccine has not even been available in veterinary medicine. Therefore, we are eager to know the results of the clinical trials and the registry. Once it is available, clinicians will have the opportunity to read the entire material, which will indicate which groups of people have been tested for the vaccine and which groups have not.

Today, we know that children under the age of 16, pregnant women, have certainly not been studied, so vaccination against these groups will certainly not be recommended. The group of older people was studied, although not very numerous. That is, if the registration agencies consider that this is sufficient data, it will be written whether it is possible to vaccinate the elderly, those with diseases that increase the risk and the like.

Will it be possible to vaccinate in principle and only those groups of individuals that were included in the study will be calm?

Such data is also emerging now that mass vaccinations have started, for example in the same J. In Great Britain, this also provides an opportunity to assess side effects. All of them, in any case, must be registered for two years for the people who participated in the study. Clearly these are primarily quick reactions, data on long-term effects will have to wait. But at least those quick reactions will allow you to evaluate and determine what is safe and what is not.

Notably, the expected vaccine is a completely new type that we have never had. How is it different and how does it work?

This is a completely different vaccine than the usual one. Until now, there have been several types of vaccines. One option was to decontaminate the pathogen itself. This can be done in two ways: the virus is completely dead, dead, as in the case of the influenza vaccine. In this case, the killed virus injected elicits an immune response. Another option is to weaken the viruses, that is, they stay alive but do not cause disease. In other words, the asymptomatic infection goes away, but the virus is still alive. Examples of such vaccines are measles, rubella, mumps, and the rotavirus vaccine. Otherwise, these are very effective vaccines because they cause an asymptomatic recurrence and immunity can persist even for life.

There is also another more innovative format for the vaccine, which uses individual viral or bacterial proteins or other components. For example, the hepatitis B vaccine is used to take only the protein of the virus, so it is not the virus itself that is injected, but only a component that is important for the immune response.

This new RNA vaccine is an RNA molecule that encodes a viral protein. Thus, instead of injecting the protein itself, the genetic material in which that protein is encoded is injected. Therefore, the RNA molecule enters our cells and produces that protein and only then does it trigger an immune response.

It has already been said that the effectiveness of Covid-19 vaccines can only reach several months. Does this mean that vaccination will still need to be repeated seasonally?

Those languages ​​are at the level of assumptions. Much like once the virus started to spread, there was a lot of talk about how long the immune response lasts and how long the antibodies persist. And that data is still being collected. When the pandemic has been going on for almost a year, there are people in China who have fallen ill again in January, in our country in March-April, and we see that in most cases the antibodies remain at least half a year. And more and time has not passed so that we can assess what.

The same is true of vaccines, with studies beginning in July and August, so the data is too recent to make clear how long that response lasts. After all, people had to get two doses, so there is still time to go, and there is no reason to believe that the protective immune response would last only a few months. As I mentioned, people who have gone through clinical trials will still be followed for 2 years. Only then will evaluations of vaccine efficacy, antibodies, long-term immune response and long-term side effects, and the like be possible.

What about people who have already had coronavirus? Will they be vaccinated?

This question is constantly being asked and we ourselves are pushing the authorized institutions to finally give an answer. At least in my personal opinion, I would think it is not necessary. The more so since those vaccines will not be enough for everyone at once, so there is no point in attacking people who have been vaccinated now, because it would certainly be a strange solution.

On the other hand, the question arises, and how then does a person know, perhaps he got sick without knowing it? Antibody tests must be performed prior to vaccination. Because one question here is the appropriateness of how much a person needs a vaccine when its quantities are limited, and another is whether it is safe. Because if it is stimulated again in the presence of an immune response, it is not necessarily a great good either.

However so far this is still a prerequisite, I would like to hope that once the registration date, the documents, there will be more information about it.

Will the vaccine already guarantee that we will not get Covid-19 or only safety complications of the disease, as emphasized, for example, in the case of influenza vaccines?

Two indicators have been measured in clinical trials: whether a vaccinated person can become infected and how often the virus develops severe forms. As far as has been announced, this vaccine not only protects against those severe forms, as there was not a single severe form or a single death in the Covid-19 vaccine group. And there were at least 10 severe cases of Covid-19 in the placebo group. There were also around 160 cases of infection here, and 8 in the vaccine group, which would show that the vaccine also protects against infection, not just the severe forms.

Fears of this new vaccine abound in society. What would you say to those who are concerned about whether it will be safe?

The vaccination record is a guarantee of safety. But it would be irresponsible to say that vaccination is completely safe for everyone, because we have yet to receive data, official recommendations. People who are really not at risk should get vaccinated.

Probably the worst anti-ad would be to vaccinate people who are not recommended to do so and who experience some strong side effects. Then talk without talking about the safety of that vaccine … So the first priority, after all, would be to ensure that the people who are at the lowest risk are not vaccinated.

I can really understand people’s fear and anxiety because the vaccine is new and so far there hasn’t been much information. Once the vaccine is registered and more people are vaccinated, there will be more data, everyone will have access to it, risks will be assessed, and there will be fewer safety concerns.

Thanks for the conversation.