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Brazilian Town’s Mass Vaccination Creates Oasis of Well-Being
SERRANA, Brazil—This town of 45,000 people in southeastern Brazil has been at the center of a unique experiment for the past three months: vaccinate nearly every adult against Covid-19 and see what happens.
In recent weeks, after most of the adults here got their second dose, Covid-19 cases and deaths plunged and life has started to return to normal as the pandemic continues to rage across Brazil.
All of Serrana’s adults were offered CoronaVac between February and April as part of the experiment, known as Project S. It is the first mass trial of its kind in which an entire town is vaccinated for Covid-19 before the rest of the country.
Not everyone in the town was eligible, including minors under 18, adult women who are pregnant or nursing, and others with serious health problems. Of the roughly 27,700 eligible adults, 27,150, or 98%, were vaccinated, according to town officials.
Town officials and residents said they are thrilled with the results so far. Infections are down 75% from a March peak in Serrana, while there have been no deaths from Covid-19 among the people who were fully vaccinated, suggesting CoronaVac is also effective against the aggressive P.1 variant sweeping the region.
In the waiting room of the town’s intensive-care unit, the effects of CoronaVac are already visible. “Only three weeks ago, this was so full, people had to stand,” said Lucia Elaine Caldano, the unit’s administrator, pointing to rows of empty chairs. In the past three weeks, only one person has been put on a ventilator—a woman who had refused to take the vaccine.
In April, six people died from Covid-19 in Serrana. Of those, five had only taken the first dose of the vaccine. The other victim had symptoms two days after the second dose, suggesting that the disease was contracted between jabs, according to Mayor Capitelli.
Serrana’s study promises to add clarity to a global mishmash of studies of CoronaVac. In Phase 3 trials carried out by Butantan late last year, it was found to be about 50% effective against symptomatic infections and 100% effective at preventing fatal cases.
The trial’s volunteers were all medical professionals, unlike in the Phase 3 trials of other vaccines such as the one developed by Pfizer Inc., meaning the volunteers were exposed to higher viral loads, potentially leading to a slightly lower efficacy rate, researchers said.