Experts Compare Effectiveness of Natural Immunity to Artificial Immunity

The natural immunity to COVID-19 that occurs after the disease is stronger than that formed after vaccination, according to experts interviewed by RBC. But this does not mean that it is not necessary to do it: even for those who have been ill, the best option is a combination of natural immunity with a vaccine.

A study comparing the effectiveness of natural and artificial immunity to COVID-19 has already been conducted by Israeli scientists. His preprint (non-peer-reviewed version. -) was published last August. In particular, the effectiveness of immunity against the delta strain, which dominated at that time, was evaluated. According to the results, those vaccinated against COVID-19 were several times more at risk of infection than those who had been ill. The best effect was shown by the combination of natural immunity and vaccination made after the disease.

Ancha Baranova , DOCTOR of Biological Sciences, Professor at the School of Systems Biology at George Mason University (Virginia, usa ), chief researcher at the Laboratory of Functional Genomics of the Medical Genetic Research Center of the Russian Academy of Sciences, noted in a conversation with RBC that there is nothing surprising in the data of Israeli researchers. “There is nothing strange in the fact that a natural infection gives immunity stronger than immunity after vaccination. But neither one nor the other immunity is eternal. This is not measles, which you had once and do not get sick again. Covid-19 disease can give immunity for about a year and a half. After vaccination, immunity is also not eternal, and here it is important to calculate the period elapsed between vaccinations. The closer the dates [of vaccination and revaccination], the stronger the immunity,” she explained.

Baranova emphasizes that it is impossible to compare vaccination and the disease: although the immunity from vaccination is weaker, the risk of severe consequences in those who are ill is much higher. “No one can claim that he is healthy and young, which means he is not afraid to get sick. This is a very dangerous lottery. Vaccination is a much more relaxed option. It is necessary that people do not think that getting sick is the best alternative, ”she emphasizes.

In addition, the expert noted that it is difficult to unambiguously interpret the data of the Israeli study. Among those vaccinated are many people from risk groups, such as chronically ill people and the elderly, who initially have lower immunity. After vaccination, they will have fewer antibodies than a vaccinated young and healthy person. This can distort the data when comparing immunity between vaccinated and recovered groups.