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Brazil’s corona vaccine: Sinovac’s CoronaVac trial disappoints



And now a new setback: good but bad vaccines.

Days after officials announced that a vaccine made by China’s Sinovac and tested on 12,000 Brazilians was 78 percent effective in preventing moderate and severe COVID-19 patients, they clarified this week that the efficacy rate of all Cases were only 50.4 percent. That’s over the criteria set by the World Health Organization – but hardly enough.

The overwhelming results were not only a setback. But for Brazil only, there are more deaths from the virus than anywhere else outside the United States. But also all countries have hoped for vaccines that are cheap, easily transported and ready for mass production. It also clarifies the role of global inequality in the spread of disease.

As richer countries use a vaccine with a higher rate of efficiency than 90 percent, the poorer countries have fewer options. As a result, health analysts warn that developing countries may cope longer with the coronavirus than wealthier nations.

“Brazil is not in a competitive place with very wealthy countries to buy vaccines like Pfizer and Moderna,”

; said Natália Pasternak Taschner, scientist advising health authorities to launch vaccines. The ability to transport, implement and maintain at the required low temperatures, we cannot as a developing country. “

Sinovac has defended a vaccine called CoronaVac, saying it is effective against severe symptoms, and its efficacy rate could prove higher for the general population than clinical workers who participated in the trial.

“The population conducting clinical trials in Brazil is quite special,” the company said in a statement. But at risk of contracting the disease only But there is also the highest risk of transmission of infection. “

Brazil and other countries plan to use the vaccine as soon as possible. Turkey said on Wednesday it had granted an emergency authorization Indonesian President Joko Widodo to broadcast the country’s first drug application.

Turkey and Indonesia announced vastly different efficacy rates for CoronaVac – 91 percent and 65 percent – according to studies that scientists said were too little to conclude.

Sinovac said some of the patterns may result from differences in international clinical trial settings. The Indonesian experiment was conducted on members of the general public, not medical workers.

Still, it is unusual for efficacy to fluctuate widely in various trials, said Arthur Caplan, chief of medical ethics at New York University’s Grossman School of Medicine.

“The difference is big enough that you start to wonder: Are they properly cared for?” Caplan said.

The WHO has long warned of the difficulties faced by developing countries quickly seeking safe vaccines. In his New Year’s speech, WHO Director Tedros Adhanom Ghebreyesus said the organization had received 2 billion doses of promising vaccines but urgently needed $ 4 billion to buy enough volumes for low-income countries. And medium

“To protect the world, we must make sure that everyone at risk, not just people, But only in countries where vaccines can be bought – he said.

The global battle has been painful in Brazil, where the disease is so deadly and Bolsonaro has encouraged the Brazilian to keep fighting. In the absence of federal leaders, the governor and the city mayor have established conflicting guidelines and procedures.

In the state of São Paulo, where more than 48,000 people have died of COVID-19, authorities have tried themselves to secure the Sinovac vaccine by setting up a large clinical trial through the Butantan Institute in Sao Paulo.

Politics quickly jeopardized the efforts.

Bolsonaro has mocked São Paulo Gov. João Doria, a bitter political competitor, for his ambitious vaccination scheme, breaking trust in vaccines. The president, who announced he would not be vaccinated, warned Brazilians that they took their own risk.

“If you turn into an alligator, it’s your problem,” Bolsonaro said. [the drugmakers] It won’t have anything to do with it. ”He added to the possibility of requiring people to sign a waiver before being injected.

Confidence in the vaccine in Brazil has dropped considerably. A survey last year found that 97 percent of Brazilians believed the importance of vaccinating their children. But now, only 72 percent of people in Rio and São Paulo say they intend to get the coronavirus vaccine.

Brazilians show special distrust of CoronaVac, where Bolsonaro supporters have attacked racist and foreign language.

But instead of easing those concerns, authorities in São Paulo have made them worse. Disclosure from clinical trials in Brazil has been delayed several times in recent weeks. Doria, widely believed to be planning to run for president in 2022, made a clear promise that he had either failed or tried to keep it. And when officials finally revealed the numbers on CoronaVac, they were greatly diminished, with no mention of any antibodies, and subsequently filled with confusion.

Last week, officials said the vaccine was 100 percent effective in preventing death and hospitalization. They say it is 78 percent effective in preventing severe infections. For his part, Doria bragged in a statement that “78 to 100 percent effective against COVID-19”.

But this week, Butantan officials, under increasing pressure for greater transparency, admitted that the effectiveness rate fell to 50 percent when accounting for patients with the condition. “Not very intense”

“Communication errors already complicate the situation and make it more complicated,” said João Henrique Rafael Junior, a researcher at the University of Sao Paulo who has been tracking misinformation about vaccines. He said the people changed the information “now they are using that to distort the image and create their own narration.”

Butantan did not respond to requests for comment.

Doria Protects Vaccines “Renowned scientists have declared their satisfaction with presenting clinical studies on the safety and efficacy of the Butantan vaccine,” he said in a statement. And the beginning of vaccination “

But it will take longer to finish a vaccination until half the effective vaccine is given, although most of them protect people from a severe reaction to the virus.

“To really get herd immunity, we need to vaccinate everyone,” said Pedro Hallal, an epidemiologist at the Federal University of Pelotas. “If you have a vaccine that is 50 percent effective, you need to cover them all to stop the spread. Of the virus No margin for errors “

Dou reported from Detroit, Heloísa Traiano in Rio de Janeiro, Kareem Fahim in Istanbul and Lyric Li in Seoul contributed to the report.


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