The inconspicuous Brazilian town of Serrana in the hinterland of the state of São Paulo awakens hope. Once just as badly affected by the pandemic as the rest of the country, the situation in the city of around 45,000 inhabitants has normalized in the last four months. Today the virus is largely under control. There are hardly any infections left, and when they do, they usually take a mild course. Relief is spreading among the population.
The reason is not a miracle, but the vaccination. As part of a study, the Butantan Institute in São Paulo, in collaboration with the University of São Paulo in the small town, observed the effects of mass vaccination on the course of the pandemic. Almost the entire adult population of Serrana has been vaccinated with two doses of the Chinese vaccine Coronavac, which is produced by the Butantan Institute and is Brazil’s main vaccine.
On Monday, the institute presented the results of the study. They show that the pandemic can be controlled as soon as around three quarters of adults are vaccinated. The mass vaccination took place in several steps, for which the population of the small town was divided into four groups. Serrana saw an increase in cases during the first phase of the mass vaccination. When the administration of the second dose began, the number of cases had already decreased significantly. And by the time three-quarters of the second dose were given, the pandemic was considered under control while the virus continued to rage in the surrounding communities. The results of mass vaccination largely coincide with scientific model calculations. However, the experiment in Serrana was the world’s first field experiment of its kind.
Serrana residents continue to adhere to safety guidelines and wear masks, but fear has given way to confidence. The authorities are already working on further experiments in the small town, for example on the implementation of large-scale events. Most Brazilians can only dream of that. In addition, tens of thousands of new cases are recorded across the country every day and around 2,000 people die in connection with the virus. The vaccination campaign is still far from the tipping point of 75 percent: 28 percent of the adult population has received the first dose of vaccination, 14 percent are fully vaccinated.