SERRANA, Brazil - The small Brazilian town of Serrana, with a population of some 50,000, has been proud of undertaking a mass immunization campaign with the Chinese-made vaccine, according to Serrana Mayor Leonardo Capitelli.

The CoronaVac vaccine developed by Chinese pharmaceutical firm Sinovac is the most prevalent in Brazil through cooperation with the Sao Paulo-based Butantan Institute, a state government-funded scientific research center. The vaccine accounts for almost 80 percent of all the doses applied in Brazil.

Located in the southeast state of Sao Paulo, Serrana is a sugarcane-producing agricultural town. Project S is the Butantan-led scheme to vaccinate the entire adult population of 27,772 and verify the vaccine's effectiveness against COVID-19.

"It is a source of pride" to be part of the project, since it is "the only one of its kind in the world for tackling the pandemic," Capitelli told Xinhua.

"Serrana will have a before and after due to the project," said Capitelli, describing the town as an "engine" of positive COVID-19 vaccine experiences.

Between Feb 17 and April 1, the Butantan Institute gradually vaccinated nearly every adult, making "a great contribution to science in Brazil and the world," said the mayor.

Mass vaccination in Serrana coincided with Brazil's second wave of COVID-19 infections, especially in February and March, with the resulting saturation of hospitals, and record number of cases and deaths due to the virus.

"The second wave hit us hard amid the vaccination, with full hospitals and exhausted doctors. But since the second dose was completed, the flow of patients has declined," said Capitelli, adding that there have been no "serious cases" since April 11.

Vaccination and the public's cooperation in the town reduced an average of 90 cases a day to just four asymptomatic or mild cases.

Immunization with the Sinovac vaccines, which took eight weeks, restored hope to the inhabitants of Serrana, perhaps Brazil's most protected town against the coronavirus.

"We have to thank our hospital, the Butantan Institute, Sinovac, and all those who helped turn our results into a model for the world," said Capitelli.

Local resident Najib Almeida Issa, 27, who manages a small restaurant and bar, told Xinhua that the vaccination campaign has provided this "oasis" with future prospects after more than a year of state-wide lockdown measures.

"The number of sales, sales in general, orders and consumption are rebounding," Issa said, and life "is returning to how it was before," since people feel "safer to go out into the streets, do their basic shopping and enter stores."

Thanks to Project S and the Sinovac vaccines, Almeida said he felt less anxious and more secure, "knowing that one has been immunized and is not going to die from this."

Elvira Bidinello, a 54-year-old homemaker who entered her restaurant to buy traditional Brazilian cheese bread, said that business has picked up as residents feel safer about going about their lives.

Bidinello said she also felt "more protected after getting vaccinated, although I don't stop taking care of myself."

The fact that the Butantan Institute chose Serrana to test a vaccine developed in China felt like a "prize," she said.

"For us it was the greatest gift we could receive... I loved it. I think whoever received the vaccine would not regret it," said Bidinello.

Standing in line at the Serrana lottery store, Camila Almeida da Silva, 31, was looking to try her fortune after coming through the worst of the pandemic.

Since the outbreak she has worked as a cleaner at Serrana State Hospital, witnessing COVID-19's impact on victims and healthcare workers.

"I was vaccinated with CoronaVac and I think that in the city many things have changed. Transmission dropped a lot and that helped commerce. We are going to try to return to normality," Da Silva told Xinhua.

Serrana saw at least 85 COVID-19 deaths, out of the more than 428,000 that Brazil has registered throughout the pandemic, and about 3,600 cases, out of the more than 15 million cases nationwide.

Looking into the future, Serrana Mayor Capitelli voiced hope that the town's status as a bulwark against the coronavirus will help attract more businesses to the bedroom community of mostly residential homes and create local jobs.

"We launched a tax incentive program so that Serrana can become a great service center. We want to generate employment and income with the fully vaccinated population," he said.