Covid-19 Invasive Strain Study in Brazil Suggests China Vaccine Limits

Researchers from Brazil, the UK and the US found that plasma from eight people who were vaccinated five months ago by CoronaVac had “failed to neutralize effectively” the new Amazonian strain, known as P.1. The study did not show whether CoronaVac can stop people from becoming ill from the opposite, one of the main goals of vaccine campaigns.

Although the sample size of the study was small and required further testing, the fact that all eight samples yielded the same result is a “particular surprise,” indicating that CoronaVac is less capable of eradicating P infections. .1 of versions of the virus previously detected in Brazil, said William de Souza, of the University of São Paulo in Ribeirão Prêto, one of the study’s authors.

Sinovac, the Chinese company that makes CoronaVac, did not respond to requests for comment. In an interview with state-sponsored broadcaster CGTN released by Sinovac this week, Chief Executive Yin Weidong said that if necessary, it would take less time to develop a vaccine for the variables than from the beginning.

“It’s like this thief we’ve already caught,” he said. “Even if it is mobile, we can use the usual research and production capability to develop a vaccine for the new variant. ”

Mr Weidong said in the interview that Sinovac had found that a person’s antibodies dropped half a year after being vaccinated with CoronaVac, adding that the company was still investigating how long protection will remain and that they will release this data shortly. He said the company is also looking into the efficiency of offering additional enhancement views.

As the P.1 strain has spread rapidly across Brazil and more than 20 other countries, concerns have grown about how well the current Covid-19 vaccines will work against the variant and the many other things that appear in the largest country in Latin America.

CoronaVac, which is expected to be rolled out across much of Latin America and other developing countries in Africa and Asia, is Brazil ‘s best hope for eradicating the disease. spread in the short term, public health experts said.

The disease has killed more than 260,000 people in Brazil. While other countries around the world have put the worst of the pandemic behind them, public health experts say Brazil is still facing its darkest days, with expectations that its daily death toll will cross the US and reach new heights in the coming weeks.

“This is the greatest humanitarian catastrophe in Brazilian history,” Edinho Silva, sovereign of Araraquara, a hard-working city in the state of São Paulo, warned this week. A recent study showed that more than 90% of Covid-19 patients in Araraquara-packed hospitals were positive for the P.1 strain.

The variant, which first appeared in the Amazon city of Manaus at the end of last year, is 1.4 to 2.2 times as susceptible to versions of the virus previously found in Brazil, and 25% to 61% more susceptible on rehabilitating people, according to a recent study.

Its impact is already being felt across the country. Hospitals in most states have already run out of ICU beds or are operating at full capacity, and a recent lack of oxygen has led to scores of patients suffering from death in the Amazon. Prosecutors have investigated reports that patients admitted to the area were tied to their beds after a shortage of sedatives.

Public health experts say Brazil is now facing a race against time to vaccinate its population ahead of other potentially new invasive changes to Covid-19. Researchers estimate that hundreds of strains of the disease are already circulating in the country, although P.1 is widely believed to be the biggest concern.

After President Jair Bolsonaro spent months playing down the pandemic and building a vaccine supply contract with Pfizer Inc. last year, the country has relied heavily on CoronaVac since they began their vaccination campaign in January. The Chinese vaccine, developed in partnership with the state of São Paulo, makes up more than 70% of Covid-19 images administered in Brazil.

Despite having an efficacy of around 50%, one of the lowest levels for any Covid-19 vaccine, CoronaVac prevented 100% of moderate and severe cases of the disease, late-stage clinical trials showed in Brazil.

The P.1 study, published on March 1, which was also commissioned by researchers from Oxford University School of Medicine and the University of Washington, provides the first indications of how CoronaVac might respond to P .1.

However, infectious disease experts including the study’s authors have warned that further broader studies are needed to show how well CoronaVac is working against new changes and whether it can still prevent it. prevented people from becoming ill from P.1.

The study itself was not designed to specifically test for CoronaVac, but to test how antibodies created either by vaccines or by previous infections from other versions of Covid-19 respond when their new P.1 strain.

“It’s a research study, a yellow light shining, but not a red one,” said Carlos Fortaleza, an epidemiologist at São Paulo State University, who was not involved in the study. “Initial results must be released with great care,” he said.

Some scientists have expressed concern that studies like this could lead to people getting vaccinated with CoronaVac, which has been heavily criticized by the president himself.

Mr Bolsonaro, a staunch critic of China, told his supporters at the end of last year that CoronaVac could force them to die or suffer disabilities, without providing any evidence. Instead it has been supported by the antimalaria drug hydroxychloroquine, and more recently the use of an experimental nasal spray to treat Covid-19 patients.

Public health experts have largely blamed Mr Bolsonaro’s administration for the country’s death tax. While many state regulators have imposed restrictions on keeping the Brazilian people at home, the president has urged people to break those rules and oppose face masks.

“Stop showering and whistling,” Mr Bolsonaro, a former army captain, said this week in what some pundits also said in an attempt to divert media attention. from a growing corruption scandal involving his son. “How long do you keep crying about it?”

—Chao Deng in Taipei contributed to this article.

Write to Samantha Pearson at [email protected] and Luciana Magalhaes at [email protected]