Opinion – Esper Kallás: Two Covid-19 Pandemics and Vaccines

Two and a half years after the discovery of the Sars-CoV-2 coronavirus, it becomes clearer that we are experiencing two distinct pandemics.

The first was caused by the virus that came from Asia, and it mutated over time to give rise to variants. The main ones were alpha, beta, gamma (which spread mainly through Brazil) and delta. Under many obstacles in prevention and without a well-established treatment regimen, the disease caused a lot of suffering and a lot of losses for two years. It was the arrival of vaccines that brought a real possibility of control.

This impact was unquestionable: vaccines prevented between 50% and 90% of cases and, even more importantly, between 80% and 95% of hospitalizations and deaths. The rapid development of vaccines was a memorable achievement, which will serve as an example for the next pandemics that we must face.

Behold, in December 2021, another variant began to require attention, the ômicron. This one, unlike the others, infecting and causing disease even in people who had already been vaccinated or even had previously fallen ill with Covid-19. New plethora of patients in emergency rooms and offices, with new disorders for everyday life.

We are certainly experiencing a second pandemic. The variants seen in 2020 and 2021 are practically no longer detected. Today, cases are caused by variants of the omicron.

Could the omicron be Sars-CoV-3? Some scientists suggest so. After all, it has very different genetic characteristics, mainly due to the accumulation of a greater number of mutations in its external structure.

More than that, subtypes of the omicron itself have already appeared. At least ten different ones being broadcast so far.

A question arises: do the vaccines we have still lend themselves to facing the new pandemic? After all, all the ones used in Brazil, for example, were made from the initial virus identified at the beginning of the pandemic. Therefore, they do not faithfully represent the omicron and its subtypes, which are currently circulating.

A study published a few days ago evaluated the cases of Covid-19 in the population of Qatar. Although the ability to prevent even mild forms of Covid-19 has dropped to close to 50% after two doses and 77% after three doses, the effect on preventing severe forms of the disease remains high.

Although the study only looked at the use of the Pfizer vaccine, the results explain what we see here, where four different vaccines were used. The number of people who needed to be hospitalized and who died from Covid-19 is much lower than that seen in 2020 and 2021. This data reinforces the important role of the vaccine in preventing serious disease. This is an indisputable fact. And it justifies the argument for the use of booster doses.

But we are still seeing people who have the most aggressive form of Covid-19, at risk of death. They are especially those who are very old or who have a very weakened defense system for different reasons, as they cannot respond adequately to vaccines.

It doesn’t seem an exaggeration to imagine that we will still need new vaccines, built from the virus that is circulating and others that emerge in the future, just like the flu vaccine.

Some heard the phrase repeated after family lunches, “as long as there is life, there will be dishes to wash.” The Covid-19 pandemics teach that we need to keep a firm eye on the coronavirus, because the second pandemic is still ongoing and we may have others ahead, for which we will need to adapt the ways of combating.