SAO PAULO -- Serrana, a town about a four-hour drive from the city of Sao Paulo, seems worlds away from the coronavirus outbreak overwhelming the rest of Brazil.
During a visit to the commuter town of about 45,000 last week, people chatted together cheerfully on benches along a major thoroughfare. No masks were in sight, thanks to a vaccination campaign that has successfully inoculated 97.7% of Serrana's adult residents with a Chinese-made shot and grabbed the attention of coronavirus researchers the world over.
"I'm glad I got the vaccine," said 47-year-old Laudair Anulai. "Now I don't have to be afraid of the coronavirus."
The experiment by the Sao Paulo state government, known as "Project S," offers a look at a post-coronavirus future for developing countries that have lost out in the scramble for highly effective Western vaccines. The program launched in February, and the last participants received their second dose on April 11.
Project S used the CoronaVac vaccine developed by Sinovac Biotech. Trials in Brazil and Chile suggested that the shot was about 50% effective at preventing symptomatic infection, a far cry from the 90%-plus rates achieved by Pfizer and Moderna.
Distrust of Chinese vaccines is widespread in Brazil. But "almost no one refused the vaccine because it was Chinese, thanks to local leaders showing that it was safe and effective," said Marcos Borges, director of the Serrana State Hospital and coordinator of the project.
"Just in my family, six people caught the virus," Anulai said. "Not getting vaccinated wasn't an option."
Serrana was hit particularly hard by the first wave of infections in Brazil last year, even relative to elsewhere in Sao Paulo state, with 10.6% of participants in a prevalence study last August testing positive.
Despite the concerns about CoronaVac, the mass vaccination campaign so far seems to have led to a dramatic decline in severe illness and deaths.
Brazil, now grappling with a second wave of infections driven by highly contagious variants, reported more than 82,000 deaths in April, a monthly record. Yet Serrana's coronavirus deaths that month plunged 70% to just six, or about a third of the nationwide level by population. None appeared to involve people who were fully vaccinated when they contracted the virus.
A cemetery in town was calm during this visit, with workers repairing graves at a leisurely pace. The atmosphere made for a stark contrast with overwhelmed cemeteries in the city of Sao Paulo, some of which have stopped accepting bodies due to lack of space.
"Last year was terrible, with bodies being brought in one after another, but it's quiet now," said Silvia Aparecida, a 53-year-old cemetery worker.
The difference was clear at medical facilities as well. The four ventilators brought into Serrana for gravely ill coronavirus patients were not in use, and an ambulance sat idle at a park near the hospital.
Sao Paulo's state government plans to release the final data on Project S this month, which is expected to show that the Chinese vaccine was effective at curbing the spread of the virus.
Yet the coast is not entirely clear. Serrana logged 235 COVID-19 cases in April -- a drop of about two-thirds from March, but still far from zero.
"Some people caught the virus even after getting vaccinated," said 59-year-old Malala Pereira, who wore a mask while waiting in line at a former coronavirus vaccination site that has is now administering flu vaccines.
Meanwhile, many restaurants in town remain closed. It will take some time to heal the scars left by the area's long battle against the virus.
The results from Serrana show some light at the end of the tunnel after more than a year of dealing with the pandemic, but limited vaccine supplies mean that many countries will have to wait to catch a glimpse. In the rest of Brazil, shots remain largely restricted to medical personnel and the elderly.
"The people in Serrana were lucky," said Diego Araujo, a taxi driver this reporter met in Ribeirao Preto, a larger city about 20 km away from Serrana. "But when are we going to get the vaccine?"