More than 300 people from Brazil gathered to protest the state Governor João Doria's support for mandatory COVID-19 vaccine.

(Photo : REUTERS/Amanda Perobelli) A demonstrator wearing a face mask with message reading "No Vaccine. Doria out" protests against Sao Paulo state governor Joao Doria and China's Sinovac potential coronavirus disease (COVID-19) vaccine in Sao Paulo, Brazil, November 1, 2020.

Apart from that, Brazil's vaccine war also covers testing the potential COVID-19 vaccine developed by China's Sinovac.

Doria has expressed interesting in making a mandatory COVID-19 vaccine for Brazil before, said Reuters.

It led to a spat with President Jair Bolsonaro who insisted that vaccinations were going to be voluntary. The country's Supreme Court's supreme justice said the high court will be the one to ultimately decide on the matter.

In late October, the Chinese CoronaVac developed by Sinovac alongside Brazil's Butantan Biological Institute showed better results, said The Brazilian Report.

Doria also declared that there were lower rates of adverse side effects related to the trials in Brazil so far.

After receiving these results, the country's Health Ministry decided that their federal government will get 46 million doses of CoronaVac.

But, in his insistence to make the vaccine voluntary, Bolsonaro blocked the agreement and said "the Brazilian people will not be anyone's guinea pig."

The protestors echoed the same sentiments, with one of the demonstrators holding a sign saying, "We are not guinea pigs."

Another protestor wore a mask saying "no vaccine" amid a crowd that also wasn't wearing masks.

"This doesn't happen anywhere in the world, not even in China," said protestor Andre Petros, pertaining to making the vaccine compulsory against Brazilians' wishes.

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According to Prensa Latina, Bolsonaro also said at least half of Brazil did not want to receive CoronaVac.

"It is a people's right. Under no circumstances can anyone force them," he argued.

Bolsonaro said that such vaccines have to be "scientifically proven" first before it gets distributed to the public, noting that the Chinese vaccine has not yet completed final clinical trials.

It is still being tests for its Phase III clinical trials with support from the Doria government.

Brazil's Mandatory Vaccines

If legislation passes, the Chinese COVID-19 vaccine won't be the only obligatory vaccine in Brazil.

Other vaccines like those for Hepatitis B are given to newborns. These vaccination campaigns have proven themselves effective in the past.

For example, polio was eradicted in the country through these efforts.

The country normally does this in cases in which the collective interest exceeds the individual. COVID-19 can classify as one of those instances as it is a health calamity.

In the giant South American region, more than 157 thousand lives have already been taken by the virus.

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Constitutional law professor Roberto Dias also told CNN Brasil that the court has to decide in favor of mandatory vaccination.

"I do not think there are many doubts about the need to require people to get vaccinated," he said.

Bolsonaro has been in contact with Washington lately, and was looking to get a vaccine from British developer AstraZeneca, said Nikkei Asia. The company is collaborating with the Trump administration.

It has also been working in Brazil. Trials for its COVID-19 vaccine candidate pushed through despite the death of one of its volunteers.

Brazil holds the record for third-worst outbreak fo the coronavirus in the world. It has 5.5 million cases after the U.S. and India.