The best vaccine is the one that is safe and effective

Publicação: 8 de January de 2021

No country will be able to vaccinate its population by choosing a single vaccine

Brazil loses its shine and trail by staying behind in the race for vaccines, leaving the people waiting for a light at the end of the tunnel

While part of the world is implementing vaccination campaigns against COVID-19, Brazil, which has already been a world reference in vaccine production and over the years has stood out internationally with the National Immunization Program (PNI) in terms of public health policy, has an imbroglio around which campaign or which immunizer should be used. Brazil, which has already eradicated, through vaccination, diseases of global reach such as smallpox and polio (infantile paralysis), loses its shine and trail by staying behind in the race for vaccines, leaving the people waiting for a light at the end of the tunnel.

While neighboring countries, such as Argentina and Chile, announced the beginning of vaccination against COVID-19, Brazil is experiencing the uncertainty of forecasting a date for the immunization campaign. For Dr. Marta Heloísa Lopes, professor at the Faculty of Medicine of the University of São Paulo (FMUSP), this reflects at least the weakness of the national policy to combat COVID-19. Still according to her, the performance of the Brazilian political authorities in relation to the pandemic and the successive changes in the Ministry of Health contributed to the delay in the adoption of effective measures to combat it, including immunization. In his opinion, the federal government should have anticipated the negotiations for the acquisition of vaccines, from different platforms, formulated by different manufacturers. “The creation of an immunization plan is the competence of the PNI, whose technical team, even with relatively few employees, has been formulating excellent national immunization programs in recent years. The acquisition of vaccines against Covid-19 for the immunization plan to take effect is the responsibility of the federal government, guided by the PNI technical team”, he adds.

Asked if the PNI, specifically in the case of COVID-19, lost prominence, Dr. Lopes recalls that the Program has in its staff technicians of great experience and competence, responsible for successful actions in previous years, supported by the Ministry of Health. “They are technicians, who need political support. In a period of serious crisis in world public health, due to the pandemic, the Ministry of Health faced situations of instability, with an interim minister for a relatively long time, in addition to the changes of ministers. This situation affects the performance of its programs. Recently, medical societies and health professionals signed a document supporting the PNI, emphasizing its importance and its interaction with state and municipal bodies to guarantee equal access to Covid-19 vaccination throughout the national territory”, points out the professor.

And vaccines, will they be approved for emergency use in Brazil? The vice president of the Brazilian Society of Immunizations (SBIm), Dra. Isabella Ballalai, is confident that yes, however, according to her, for this to occur some points that are under discussion need to be reviewed by the National Health Surveillance Agency (Anvisa) in order to facilitate, at least for vaccines that are already in large-scale use in other countries. “We already have millions of people who have used some of the vaccines and the expectation is that Anvisa will find a way to speed up the release process for emergency use at this time of global crisis. We hope that the criteria for approval of these vaccines will find a simpler and faster way for licensing”, she says.

Regarding the best vaccine for Brazil, Dr. Ballalai is categorical in stating that all vaccines that prove to be safe and effective for the population are welcome and need to be well received by the country. According to her, no country will be able to vaccinate its population by choosing a single vaccine. “Brazil, for example, has a population of more than 210 million people and we cannot afford to have a single manufacturer, let alone choose the vaccine”, she justifies by emphasizing that the best vaccine is the one that is safe and effective and all will only be available if these conditions are met.

Dr. Lopes agrees. “The best vaccines are those whose effectiveness and safety studies show reasonable results. It is likely that in a country as big as Brazil, it may be necessary to simultaneously use vaccines from different platforms, produced by different laboratories”, she points out. Also according to her, a carefully designed and well conducted immunization campaign can take advantage of this situation: a) by distributing vaccines according to the conditions of the place, for example, using vaccines that require storage conditions at low temperatures, in centers that have conditions for this, and vaccines that can be stored between 2 and 8 degrees Celsius in more remote locations, without infrastructure for storage at low temperatures; b) comparing results of different vaccines applied in different regions; c) investigating the sequential use of different vaccines, for example, making the first dose with one product and a second dose with another. All of this, if well planned, could increase the supply of vaccines and allow the knowledge acquired to be applied in other countries as well.

Vaccination is one of the most effective public policy strategies for preventing infections and epidemics. The centuries have passed and unfortunately Brazil is among the countries in which a portion of the population does not trust the efficacy and still fears vaccines. Theories are practically the same, that vaccines have the opposite effect, even with figures showing the opposite. The war of narratives and misinformation affects the work of scientists and health professionals.

About Coronavac, which has generated suspicion that something is wrong, Dr. Ballalai sees it as a good vaccine, as promising as all the others, but which is involved in a political dispute that generates doubts and myths in the general population. She explains that China already uses and has applied millions of doses – started to vaccinate its population even before licensing – without any reports of a serious adverse events in relation to it so far. “I understand that Brazil will not do that at this moment and that the publication of phase 3 data is very important for Coronavac to be a reality for our country”, she points out. About AstraZeneca’s delay in reviewing data, Dr. Ballalai does not see it with concern or even that it means a long delay. This is good news, since this is the main bet in Brazil – more doses compared to other manufacturers. “But what draws attention is Pfizer’s withdrawal from emergency licensing, considering that Anvisa’s requirements would make final licensing easier”, notes the vice president of SBIm.

Asked about the vaccination process, which will be long and uneven due to the lack of resources for access to doses and the necessary infrastructure for maintenance and distribution, Dr. Ballalai recalls that the PNI has great experience in campaigns and the vaccination process does not have to be so long. According to her, everything will depend on the inputs and vaccines that we will have so that the PNI redefines the phases that it has already presented. The target audience will not change, what can be changed are some strategies for the distribution of different vaccines, to different regions, considering the cold chain, access, epidemiological curve, are some factors that may be necessary if we do not have the 100 million doses from AstraZeneca, developed by the University of Oxford in partnership with Oswaldo Cruz Foundation (Fiocruz). It is worth noting that the pandemic reversed the vaccine purchase processes, which usually arrived in private networks and were then made available in the Unified Health System (SUS). This time, it will be the opposite, since the agreements are being made between companies and governments.