What is revaccination against coronavirus and why is it needed

What is booster vaccination?

Revaccination is the repeated administration of a vaccine some time after a person has already been vaccinated. Usually the vaccination is repeated every few timesEveryone should know this! Questions and Answers on Vaccine Prevention / Department of the Federal Service for Surveillance on Consumer Rights Protection and Human Welfare in the Tomsk Region years old. But the frequency depends on the specific disease the vaccine is fighting against.

For example, a tetanus booster is given every 10 years. And against the flu - once a year.

Why is it needed?

In fact, this procedure is not always required. Its need depends on two factors:

1. The stability of the immunity that is developed in response to the first vaccination.
2. The ability of a pathogen to change.

If we take, for example, yellow fever, then it is enough to protect against itYellow Fever Vaccine / CDC be vaccinated only once. Having received an injection, the body forms such a powerful immunity that it lasts for life. And the yellow fever virus does not differ in variability, therefore it cannot slip through the formed defense.

However, in the case of other infections, the body's self-defense may be less persistent. For example, sometimes the immunity developed after vaccination decreases significantly over time. Or another option: the virus targeted by the vaccine mutates easily. The body cannot recognize new versions (strains) of the pathogen and misses the blow. To maintain protection, it is necessary to familiarize the immune system with the modified infection in time.

Revaccination is a way to both train the immune system and strengthen a weakened immune system. In the English-language medical literature, repeated vaccinations are calledBooster Shot. Definition / MediceneNet - booster (supporting, intensifying) vaccines.

How often is revaccination for coronavirus required?

At the end of June, Minister of Health Mikhail Murashko, in an interview with the Russia-24 TV channel, saidThe Ministry of Health has developed recommendations for revaccination against coronavirus / TASS: according to experts from the Ministry of Health, vaccination against coronavirus infection will have to be repeated every few months.

Mikhail Murashko

Minister of Health of the Russian Federation.

So far, we see that during the period of an epidemic rise, this will need to be done in six months - both for those who have recovered and those who have been vaccinated earlier.

If the epidemiological situation improves, then revaccinating, according to Murashko, will be possible once a year.

Apparently, Russian doctors believe that booster vaccinations in the event of COVID-19 cannot be dispensed with. Immunity to the disease seems to be declining quite rapidly (there is some evidence for thisKai Wang, Quan ‑ Xin Long, Hai ‑ Jun Deng, Jie Hu, Qing ‑ Zhu Gao, Gui ‑ Ji Zhang, Chang ‑ Long He, Lu ‑ Yi Huang, Jie ‑ Li Hu, Juan Chen. Longitudinal Dynamics of the Neutralizing Antibody Response to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS ‑ CoV ‑ 2) Infection / Clinical Infectious Diseases), and it should be increased regularly.

But if there are antibodies, you don't need a booster shot?

Yes, indeed: the presence of antibodies reducesRaymond A. Harvey, Jeremy A. Rassen, Carly A. Kabelac, et al. Association of SARS ‑ CoV ‑ 2 Seropositive Antibody Test With Risk of Future Infection / JAMA risk of contracting COVID-19. But what their level should be in order to provide effective protection against coronavirus infection is not yet clear. Situations are possible when antibodies seem to be there, but there are too few of them to resist the rapidly multiplying virus.

Apparently, on this basis, the head of the Moscow Department of Health at the end of June stated quite categoricallyRevaccination from COVID in Moscow will be possible in a few days / RIA Novosti that's what:

Alexey Khripun

Head of the Moscow Department of Health.

The level of antibodies does not matter. In six months he is the kind that just requires revaccination.

The logic behind this statement is as followsVaccination after illness and revaccination: is it necessary and how soon? / BBC News. Russian service. To cope with the currently widespread strains of coronavirus (in particular, we are talking about option delta), the highest possible level of antibodies is required. And this can be achieved only if you regularly boost immunity with a booster vaccine.

And what do they say about revaccination against coronavirus in other countries?

Experts disagree.

So, in a comment to the news agency Reuters, Pfizer Inc (PFE.N) CEO Albert Burla saidTop scientists question the need for COVID-19 booster shots / Reuters about the same as the heads of Russian health services. That people are likely to need a booster dose of the vaccine every 12 months to maintain high immunity against COVID-19 and its new strains.

But there is also another position. Moreover, it belongs to experts representing the most authoritative medical organizations in the world.

Kate O'Brien

Director of the Department of Immunization, Vaccines and Biologicals, WHO.

We do not yet have data that would allow us to unequivocally establish whether booster doses are needed.

The same opinion is expressed in the reportOverview of data to inform recommendations for booster doses of COVID ‑ 19 vaccines / ACIP Meeting. June 23, 2021. CDC United States Advisory Committee on Immunization Practices (ACIP): There is currently no information available to provide a clear recommendation for revaccination. More research is needed.

And if I do not want to be revaccinated, can I refuse?

There is a little more certainty here. Of course. Revaccination, like vaccination, is purely voluntary. True, with some nuances.

An excellent example of this is the commentary given to RBC by the press secretary of the President of the Russian Federation Dmitry Peskov. Explaining why obligatory vaccination of service workers in Moscow can be considered voluntary, the politician saidThe Kremlin explained the voluntariness of vaccination with the opportunity to change jobs / RBCthat those who are dissatisfied with the idea of ​​vaccination may not torment themselves, but simply change their jobs.

It is possible that the same voluntariness will apply in other areas, and for re-vaccination.

How will revaccination against COVID-19 take place?

The Minister of Health of Russia announced on June 21The Ministry of Health has developed recommendations for revaccination against coronavirus / TASSthat the Ministry of Health has developed recommendations for revaccination against coronavirus. However, they have not yet been officially published.

What drugs will revaccinate against coronavirus?

This is also not clear yet. Theoretically, all vaccines registered in the Russian Federation are suitable for these purposes: "Sputnik V" ("Gam-COVID-Vac"), "EpiVacCorona", "KoviVak". In addition, a drug is on its wayVaccine "Sputnik Light" entered the civil circulation / Interfax "Sputnik Light".

As reportedRevaccination in Moscow will take place with the Sputnik Light vaccine / Interfax Interfax, revaccination against coronavirus in Moscow will be the last resort. The same Sputnik Light is planned to be used to vaccinate labor migrants.

Author and editor of articles on health, psychology, sexology. I have been working in medical journalism for over 15 years. I rely on the principles of docmed, love and know how to search and analyze relevant research in world scientific journals. I try to write about the most complex diseases in a simple and accessible way. I believe that understanding the mechanism of the development of the disease means taking the first step towards recovery.