Find out about the Covid-19 vaccine that will be used in teenagers

The Pfizer vaccine, according to estimates by the state health secretary, Nisio Fernandez, should become dominant in the national immunization plan (PNI) within the next 90 days as doses become more available. Thus, it opens the possibility of vaccinating adolescents without compromising the care of other groups.

This immunizing agent was licensed by Anvisa for 12 to 15 year olds in June. Previously, only people over 16 years old could be vaccinated with Pfizer in the country.

In Espírito Santo, the first adolescents to receive the vaccine will be those with comorbidities.

Although permitted in Brazil, vaccination of adolescents can only be started when at least 90% of subsequent age groups have been immunized with the first dose.

Pfizer was the first manufacturer to announce the results of its study of 12 to 15-year-olds, in early May, with a 100% efficacy rate.

According to the results of the phase 2/3 pooled study on adolescents, which began on October 12 last year, 16 cases of Covid-19 were detected among 2,260 adolescent participants, all in the placebo group.

In addition to the efficacy data, the vaccine has also been shown to be safe. The immunity of the vaccine, i.e. its ability to induce an immune response in the body, was almost twice as high in the 12 to 15-year-olds as in the 16-25-year-olds.

Upon completion of the study in this age group, the US regulatory agency, the FDA, in early May authorized the use of the vaccine for people over 12 years of age. In the United States, Pfizer has already been applied to the entire population over 16 years of age. The UK and EU also approved its use in children under 16 at the end of May. In Latin America, Uruguay was the first country to begin immunizing adolescents in June.

In the general population, Pfizer’s Covid-19 vaccine is 95% effective, but with the delta variant, it loses some of its ability to stimulate the immune response in the vaccinated population.

The Pfizer vaccine uses messenger RNA (mRNA) – an acid that is already produced in the human body – to provide protection to the person receiving the immunizing agent, which creates antibodies against the SARS-CoV-2 virus (coronavirus). Instead of introducing the attenuated or inactive virus into the body, the immune system “teach” the cells to make a protein that stimulates the immune response of the vaccinated individual.

mRNA vaccine, according to Pfizer’s website, mimics the process that occurs in the body of a person who has already had the disease, but in a way that does not allow the person being vaccinated to be infected – just educating the body on how to respond to that invader.

Pfizer and BioNTech have also started studies to verify the safety and effectiveness of the fortifying agent in the age group between 6 months and 11 years. The first results of the survey are expected to be published by the end of this year.

Butantan, in turn, already has research results of applying Coronavac – a vaccine produced by the institute in the country – in children aged 3 to 12 and has asked Anvisa to include that age group in the package leaflet for the immunizing agent. The request was denied by the federal agency, on the grounds of lack of data and a small study group, but the decision could be reviewed.

This refusal, according to Nisio Fernandez, frustrates the expectation of being able to vaccinate children and delays the beginning of the procedure, but it is not a decision that affects, for example, the vaccination schedule for adolescents.

In Espírito Santo, there is a demand for 360,000 adolescents to receive the vaccine, but deciding the strategy is up to the Ministry of Health. Nicio Fernández hopes to be able to start serving this audience in September, although now the third dose (D3) is for the elderly and those with suppression Immunosuppression is mainly from Pfizer.

When asked if the two measures can be implemented, the minister emphasized that one does not make the other impossible. But, most likely, teens without comorbidities will start receiving care by the end of next month, after the booster is started in the elderly.