Sao Paulo (AFP)

"I want to participate, it's my contribution to science," explains pediatrician Monica Levi, one of the volunteers in Sao Paulo of one of the most advanced coronavirus vaccine programs, which has already made more than 87,000 dead in Brazil.

"My credo is vaccination. So I have to be consistent with what I believe in", adds Dr. Levi, 54, who has been practicing for 23 years in the Clinic specializing in infectious and parasitic diseases and in Immunology (Cedipi) of the South American megalopolis.

This specialist is one of the 5,000 "guinea pigs" participating in Brazil in phase III tests - the last before approval - of the ChAdOx1 nCoV-19 vaccine, developed by the University of Oxford and the British laboratory AstraZeneca, also tested in UK and South Africa.

The large South American country is also the first country to launch phase III tests of the Chinese vaccine Coronavac, from the Sinovac Biotech laboratory.

The volunteers are recruited mainly from health professionals who, by their profession, are the most exposed to the virus in this country, the second most affected in the world by the Covid-19 pandemic after the United States.

"They chose health professionals because we are constantly exposed. The requirements: to be between 18 and 55 years old, to work in contact with the public, not to present co-morbidity factors (ie risk), and not be pregnant, ”explains Monica Levi of the selection process.

"Everyone is interested in studying (vaccines) in places with a lot of cases, like Brazil. The country is on a continuous plateau (in the number of infections and deaths), so we can compare the results of several tests, "she continues.

When Monica Levi told her family that she was going to serve as a "guinea pig", her two daughters accepted her decision and her friends congratulated her. Some colleagues felt it was a risky but courageous choice.

- "Headache, cold sweats" -

Half of the volunteers receive the vaccine, while the other is given a placebo.

To limit the side effects, everyone takes paracetamol during the first 24 hours.

Monica Levi, who received an injection on July 21, describes feeling "a headache and cold sweats" on the first day. "But I don't know if I had the vaccine or the placebo," she says.

She will only know in a year, during which all volunteers will have to go to medical consultations regularly. "We will have blood samples taken, which will be analyzed by (the University of) Oxford," says Levi.

The largest laboratories are engaged in a race against scientific and commercial time to curb the spread of Covid-19, which has already infected more than 16 million people (including 2.5 million in Brazil) and killed more than 650,000 in the world.

"Normally, a vaccine is approved when the trial is over. But with this pandemic, we are facing an emergency situation and it is possible that the regulatory bodies give their green light with still partial data", underlines the Brazilian specialist.

"We must not wait a year. A lot of people will die if we follow the usual protocols," she insists.

The Oxford vaccine "is already being produced on a large scale even without having been licensed. When it is authorized, we will have a large quantity available and production will not start from zero", argues Dr Levi . doctors

But if the vaccine proves ineffective, "everything will go in the trash".

© 2020 AFP