Should recoveries vaccinate against COVID-19? If so, should they take two or just one dose of the vaccine? Doubts were explained by prof. Andrzej M. Fal from the Ministry of Interior and Administration during the online press conference "Vaccination plan against COVID-19", organized by PAP as part of the educational cycle "Science will win" - Science will win.

Some people who have had COVID-19 are wondering whether they should be vaccinated against COVID-19, since they have already acquired immunity in the form of antibodies. Some people think that they only need one dose of the vaccine instead of the usual two doses, which is administered a few weeks apart, fearing that after two doses the vaccine will be more severe.

As admitted by prof. Andrzej M. Fal, specialist in internal diseases and allergology, head of the Department of Allergology, Lung Diseases and Internal Diseases at the Hospital of the Ministry of Interior and Administration in Warsaw,recoveries undoubtedly have a higher level of antibodies. However, a lot depends on when they got sick.

- The person who underwent COVID-19 in March 2022 and the one who fell ill in the fall are both a healing person for us.The one who fell ill in March probably no longer has antibodies.Even if she has these antibodies, the administration of the first dose should not provoke any significant reactions - he assured.

During the conference, experts emphasized thatin order to obtain full immunization, vaccines must be administered in accordance with the drug protocol . Each vaccine has a well-established number and schedule of doses. - So I am not convinced by this idea (giving one dose of the vaccine), I hope it will not work. The only reason for this was the temporary restriction of vaccines. In my opinion, this is not the right way - argued prof. Andrzej M. Fal

Prof. Andrzej M. Fal explained that the most commonly administered mRNA vaccine should be administered 21 days apart. This is due to clinical trials. - These have shown that after the first vaccination the antibody level increases, but not satisfactorily. - he said.

He noted that after the first vaccination, memory (immune) cells, both type B and T, are mainly produced.first vaccination effect. At the level of antibodies that work immediately,after the second dose, the level of antibodies increases dynamically , it is much higher than in the case of convalescents, i.e. people who suffered from COVID-19 and recovered. According to the expert, they are even incomparable. Vaccination causes the production of memory cells, which, in the event of future exposure to the virus, will make the immune system itself start producing large amounts of these antibodies.

As explained by prof. Andrzej M. Fal, the vaccine does not administer the whole virus, but only a fragment of its genome, and only one that is not normally available for antibodies. - It's something that's hidden inside the virus. There should therefore be no contact reactions with the pathogen. Because this is not the code in this fragment of the genetic material - he emphasized.

One of the vectored vaccines, which is soon to be registered in the European Union, will probably only be given in one dose. The AstraZeneca vectored vaccine already in use is given in two doses. - There are two elements that decided about it - explains prof. Halyard. - The first is a matter of vector. Most often it is adenovirus, which is supposed to trigger an immune response in the body. It may happen that after the first injection of the vaccine, this vector will cause an immune reaction, and in the second injection, the body will destroy this vector before it has time to transfer the genetic material to our cell. One vaccine turned out to be more effective when the time interval between the first and second doses was increased.

This is probably why the creators of another vaccine, incl. developed in Russia, they decided to use two different vectors for the first and second passes to avoid this from happening. But other manufacturers will rather opt for one dose to avoid the possibility of inactivating the second dose.

Prof. Fal explained that you cannot get COVID-19 after the mRNA vaccine because it does not contain the virus. - We stimulate the body for one purpose only, so that it produces antibodies. Therefore, there are no symptoms of viremia, only a stimulation of the immune system. In the case of a viral infection, even asymptomatic, as in the case of SARS-CoV-2, we have a risk of deterioration of the functions, primarily of the heart, lungs, kidneys and the central nervous system. This does not happen after vaccination - emphasized the expert.

Source: PAP