After informing that the CoronaVac vaccine, from the Beijing-based company SinoVac, is effective against the SARS-CoV-2 variants detected for the first time in South Africa and England, the Butantan Institute in Brazil started with this vaccine and funding from the state of Sao Paulo a large-scale experiment.
With exceptions such as pregnant women, the entire adult population, around 30,000 people, will be vaccinated in the town of Serrana, which has a total of about 50,000 inhabitants, in order to track the effects of vaccination on the transmission of the coronavirus.
The proposal is striking because Butantan was the same institute that, after CoronaVac had been reported to be 91.25 percent effective in Turkey, reported that in the trial in Brazil it had been 50.4 percent effective.
To the above, it is added that it has not yet been announced whether CoronaVac is effective against the variant of concern P.1, detected in Brazil itself. Butantan reported that it is currently conducting a clinical study in Manaus, the city most affected by P.1, and that the results will be available “soon.”
CoronaVac is the first “traditional” inactivated virus vaccine that has been approved (in Mexico, Brazil, China, Chile, Colombia, Indonesia and Turkey); However, according to the Covid-19 Vaccine Tracker site, none of the five clinical trials that are underway have yet been completed. Data on its efficacy against the variants of concern were also not presented.