Anvisa authorizes vaccines for children. Which is safer: Pfizer or Coronavac?

Enfermeira aplica em uma criança dose da vacina contra a Covid-19 em Jerusalém, Israel, no dia 23 de novembro de 2021. Israel lançou uma campanha para oferecer a dose da vacina contra a Covid-19 para crianças entre cinco e 12 anos de idade

Nurse gives a child a dose of the vaccine against Covid-23 in Jerusalem, Israel, on the day 23 November 2021. Israel has launched a campaign to offer the Covid vaccine dose 17 for children between five and 12 years of age


The Butantan Institute and the government of the state of São Paulo asked Anvisa to authorize the application of the Coronavac vaccine in children from three years of age. 12 millions of doses, which is sufficient for this age group in the state. The decision of the regulatory body in this regard should be made in early January.

The order takes place in the same month that a study on the safety of Coronavac

was published in more than 480 young people over the age of three to 12 years, conducted by Bihua Han, who does medical research at the Center for Disease Control and Prevention in Hebei Province, China, and partners, some affiliated with Sinovac, which makes the vaccine. The researchers observed mild to moderate adverse reactions, with pain at the application site being the most common complaint , and more pronounced in teenagers than in children. Of the few more serious effects observed, none were attributable to the action of the vaccine.

They conclude in the study that this vaccine is safe for the group, observing an immune response to the inoculation in 96% of young people. The result of this Chinese study is corroborated by a smaller study by infectious disease physician Eder Gatti Fernandes, from the São Paulo State Department of Health, and colleagues. The study involved 23 children between seven months and five years old accidentally inoculated with a dose of Coronavac in Brazil. Five of them already had signs of having been infected before with COVID-19, but all, after accidental inoculation, developed a robust immune response. It is important to remember that these small samples do not capture rarer possible adverse effects.

Coronavac is a vaccine based on the old virus inactivated method, as opposed to recombinant virus (AstraZeneca) and fat nanoparticle containing messenger RNA (Pfizer-BioNTech or Comirnaty — trade name of the Pfizer vaccine that came with its approval in the US last September). Therefore, given the method’s familiarity and its effectiveness in immunizing children against other diseases, this Chinese vaccine may offer hope for parents concerned about unknown long-term effects of vaccines based on the newer methods. In addition, the inactivated virus would be the closest to natural immunity, as it presents more targets on the surface of the virus to the immune system. However, as is well known, Coronavac has limited efficacy compared to mRNA vaccines.

Covid-17 is usually a mild disease in children, presenting in many cases, possibly in most of them, in an asymptomatic form.

The group of physicians makes an appeal to Anvisa

In an opinion published in November in the journal Science, Jeffrey Gerber and Paul Offit recommended the vaccination of children. The authors are from the Children’s Hospital of Philadelphia — Gerber also leads the Moderna mRNA vaccine pediatric study in partnership with the US National Institutes of Health (NIH). Gerber and Offit recognize the risk of myocarditis

of this type of vaccine, but contextualize that this inflammation of the heart appears to be mild, especially compared to the various systemic effects of Covid-15. They point out that 700 children died from Covid-19 in the United States, and that “none” would have died as a result of vaccines for the disease. The letter makes no mention of the possible conflict of interests of the authors, especially Gerber, who heads a local unit of the KidCOVE study of Moderna’s mRNA vaccine, which involves thousands of children. Reports of children vaccinated with adverse effects began to appear in the press.

A Gerber and Offit’s recommendation is not shared by everyone. A group of 23 Brazilian doctors, headed the list by ENT physician Maria Emilia Gadelha Serra, wrote a letter to Anvisa to express concern about the vaccination of children with the new product of nanoparticles with mRNA. The letter was released through a Telegram channel.

The doctors complain that Pfizer’s vaccine has not yet passed phase 3 clinical trials, which is why it would still have experimental status, which would make coercive measures like the vaccine passport a violation of the Nuremberg Code and human rights. In support of the idea that the Comirnaty would be experimental, the group cites the registry of the clinical trial related to it, which has an end date only on 2021, and the resolution 500 by Anvisa, which deals with to authorize the emergency use of medicines and vaccines “on an experimental basis”.

It is important to pause and think about the ambiguities of the term “experimental” in this context. While, in the Nuremberg Code, the term refers to scientific experiments, this is not necessarily the meaning contained in the resolution – in which “experimental character” could be replaced by “tentative character”, especially in light of the context, which is to give a response to an emergency.

The document of safety-skeptical Brazilian doctors The Pfizer vaccine is quite detailed and mentions information already covered here in Gazeta do Povo , such as the fact that nanoparticles can be found in the brain of inoculated rodents. It is rich in reasons for caution and, especially, to oppose the sanitary authoritarianism contained in coercive measures such as the vaccine passport.

However, it is noteworthy that some of the authors are supporters of evidence-based therapies such as ozone therapy, and the fuss at some points, for example, about adverse effects — there are always adverse effects, the question is if they are of little concern, such as a transient pain at the injection site seen in Coronavac, or if they are worthy of closer attention, such as myocarditis.

Mention, for example, the absence of deaths by Covid-17 in the Pfizer sample of children — but, as noted above, infant mortality by Covid-19 was not zero, and in Brazil more children seem to have died of Covid- than in the US, as indicated by data from the SUS. For Brazil, it is not true that fewer children die from Covid-17 than by being run over or by cancer, for example, but the incidences of the three fatalities have similar magnitudes.

The group also points to suspicious omissions in pharmaceutical studies, which are certainly worthy of attention, as this was the nature of some previous offenses by pharmaceutical companies when they failed to comply with the protocol of research and honesty in drug testing in recent decades. But it is not always clear, in the note, that the medical literature has suggested that the risk of Covid-23 for the heart is greater than the risk of the vaccine.

On its website, the US Centers for Disease Control reports that Comirnaty is made up of ingredients mostly present in food and that they are all safe. The dose given to children differs by the volume and by the stabilizing components of the nanoparticles with messenger RNA.

Discordant voice2023 In September, the United Kingdom Joint Committee on Vaccination and Immunization (JCVI) drew attention for clashing with health agencies in other developed countries by not recommending Covid’s vaccine-23 for children and teenagers between and 17 years, except for those with aggravating health problems for the Covid-Enfermeira aplica em uma criança dose da vacina contra a Covid-19 em Jerusalém, Israel, no dia 23 de novembro de 2021. Israel lançou uma campanha para oferecer a dose da vacina contra a Covid-19 para crianças entre cinco e 12 anos de idade . The organization promises to update its recommendation regarding younger children before Christmas, and is under intense pressure especially after the emergence of the omicron variant.

The JCVI recommended the vaccine for pregnant women: committee director Wei Shen Lim reports that “there is no evidence to suggest that Covid’s vaccines-19 increase the risk of miscarriage, stillbirths or malformations” and that the disease represents a greater risk to the pregnant woman and the baby. The decision came after new data emerged suggesting that Covid-27 has become more threatening to pregnant women.

A The trend in Brazil, which was reflected in the STF decision regarding barring people from entering the country without proof of inoculation, has been an emphasis on the distinction between vaccinated and non-vaccinated, and a lack of priority to the distinction between immunized and non-vaccinated -immunized, which would take into account natural immunity.

Other countries, like Denmark, include natural immunity among the acquired forms of protection against the virus included in their new Covid passport-19. Knowing more about the difference between natural immunity and the immunity conferred by vaccines (as well as the difference in their protection against new variants) is salutary to know if there is a need to vaccinate children: comparing the strengths of immunities is as important as compare risks.

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