A study in Lithuania provided new insights into the effectiveness of coronavirus vaccines: why they don’t protect everyone

The gap was covered by hematologists from the Santara Clinics, who conducted a study on the effectiveness of the vaccine in patients with blood diseases.

Professor Laimonas Griškevičius, hematologist at the Santara Clinics, told the “Delfi rytas” program what they managed to discover and how they managed to protect immunosuppressed people from the coronavirus in the most effective way.

– Professor, you and your colleagues conducted a study on the efficacy of the world’s largest vaccine sample in patients with blood diseases. Tell us what you found out.

– The efficacy of vaccines in healthy volunteers has been investigated. People with impaired immunity were not included. Therefore, neither we, nor the scientists of the world, nor other doctors knew how these vaccines affected immunosuppressed people and, in general, if they were effective.

That’s why we started this study, which involved nearly 1,000 people with blood diseases.

We take the blood of these individuals prior to vaccination. Then we did a full vaccination as it should be done.

After vaccination, we perform repeat blood tests to check the development of immunity and the development of antibodies against the coronavirus in the blood of these individuals.

We find that about 40 percent. our patients developed strong and effective immunity. Unfortunately, the immunity was weaker for the rest. About 40 percent had weaker immunity, and 20 percent of the patients did not develop immunity to the coronavirus at all. These patients remained vulnerable to infection.

We also discovered the factors that contribute to that weakened immunity.

– So why does an immunosuppressed person who does not have any health problems develop immunity after one or two vaccines?

– Blood disease itself weakens the immune system. This is well known. And we know that our patients often suffer from a variety of infectious diseases: both viral and bacterial.

Furthermore, the treatment we apply to our patients is usually one of the side effects of even greater immunosuppression.

Here’s what we’ve noticed: In patients who have no cure for remission, the response to the vaccine is poor. This response is further aggravated in patients receiving a treatment that is particularly powerful in suppressing the immune system. These patients remain vulnerable to viral infection.

– Has the immune response to vaccines from different manufacturers been studied? Maybe one made it stronger?

– In Lithuania, all people with blood diseases were vaccinated with Pfizer at that time. However, we are studying the response to this particular vaccine.

However, from our colleagues’ studies, which were certainly smaller, the answer is that the response to all vaccines is quite poor.

Also, Pfizer, or so-called mRNA vaccines, produce some of the strongest immune responses. As a result, basically our patients received one of the “strongest” vaccines. However, some patients have not yet developed an immune response. Therefore, studies conducted by both us and our colleagues show the same thing: in some patients with blood diseases, the immune response to vaccines is poor.

– Are only patients with blood diseases vulnerable and need additional protection? What other groups of people are vulnerable? To what extent is this problem?

– Patients with blood diseases probably have the worst immune system due to their blood disease and treatment. Instead, we study the more complex group of patients.

However, there are other groups of patients whose response to the vaccine is relatively poor. These are patients who are receiving immunosuppressive therapy for other diseases. Such patients have, for example, immunosuppressed diseases, as well as post-transplant patients, since they have to take immunosuppressive drugs for a long time, especially after organ transplants. Our colleagues and researchers around the world have noted that the response of these patients to vaccines is also not optimal.

– How can these people be protected?

– There are solutions to protect them. Several studies have already emerged suggesting that additional doses of the vaccine can enhance the immune response. Therefore, these patients should be revaccinated first, with one or even two doses of the vaccine. Probably one-third to 50 percent. the response of these patients would improve: it would be more effective, we would find more antibodies and we would improve protection.

Another important thing is that those around them who provide them with medical, social, or home services, are vaccinated. That is, safety bubbles must form: by vaccinating all doctors, we would significantly reduce the chances of infecting these patients with coronavirus infection by at least 10 times.

Well, it is important to apply routine safeguards in addition to testing.

– What are other countries doing about it? Perhaps some are already using a booster dose of the third dose?

– The first countries to announce and initiate revaccination are Israel, which only recently announced that it will vaccinate the most vulnerable with a third dose of the vaccine; France has been vaccinating some people, including the most vulnerable, with a third dose for some time; the UK has also announced that it is likely to re-vaccinate these people in the near future.

Thus, little by little, the state is paying more attention to this problem.

In fact, one solution is the booster vaccination.

– Yesterday in Lithuania, a meeting of the Council of Independent Government Experts was held, during which the experts also supported the recommendations that you have made today. Perhaps the position of the Ministry of Health is already known (on this issue?

– I had to attend this session. Experts understand the importance of the problem and have recommended booster vaccines, but the decisions will be made by the health minister.

From the discussions, I have the impression that the Ministry is inclined to accept these recommendations.

– When should the third dose of the groups of patients that we have mentioned be vaccinated so as not to be late?

– As soon as permission is obtained, we will start revaccination, as it takes time for immunity to develop. In addition, an increase in the number of cases is observed and patients should have the opportunity to improve their immunity and provide protection without waiting long.

– Shouldn’t the same start with the doctors who were the first to get vaccinated?

– There is currently no recommendation in the world to vaccinate healthy people with a booster dose of the vaccine, although studies, especially in Israel, show that immune protection against coronavirus infection weakens over time.

However, the Santara clinics currently routinely test all physicians to determine how many antibodies were left after the vaccination that the Santara clinics received half a year ago. With this study, which will examine more than a hundred or maybe even a thousand doctors, we will find out what the immune situation is between healthy volunteers and doctors and then it will be possible to decide on their booster vaccine.