The vaccine developed by Sinovac Biotech Ltd. is eradicating Covid-19 among Indonesian health staff. It is good news for the millions of developing countries that depend on the infamous Chinese vaccine, which performed much worse than western vaccines in clinical trials.
In an interview on Tuesday, Health Minister Budi Gunadi Sadikin said that Indonesia followed 25,374 health workers in the capital city Jakarta for 28 days after they received their second dose and found that the vaccine saved 100 percent of them from death and 96 percent from hospitalisation as soon as seven days after they received their second dose. The employees were tracked until late February.
Sadikin also said that 94 percent of the workers were safeguarded from the infection, which is a remarkable finding that exceeds the results of the shot's numerous clinical trials, but it's uncertain if the workers were uniformly tested to trace asymptomatic carriers.
According to Sadikin, in hospitalizations and deaths among medical personnel there's a "we see a very, very dramatic decline." It's unclear which strain of coronavirus Sinovac's vaccine was effective against in Indonesia, but the country has not reported any significant outbreaks caused by variants of concern.
The findings support reports from Brazil that the Sinovac vaccine is more successful than it was in research, which was marred by varying efficacy rates and concerns about data transparency. The CoronaVac vaccine's efficacy was just above 50% in the company's largest Phase III trial in Brazil, the lowest of all first-generation COVID vaccines.
Sinovac's spokesman in Beijing said the company couldn't comment on the Indonesian study until it had more details.
Yin Weidong, Sinovac's chief executive officer, defended the gap in clinical data surrounding the shot, claiming that there is growing evidence CoronaVac performs better in the real world. However, real-world examples suggest that the Sinovac shot's ability to contain outbreaks necessitates vaccination of the overwhelming majority of citizens, a scenario that developed countries with weak health systems and restricted access to vaccines are unable to achieve rapidly.
Nearly all of the people surveyed in the Indonesian health worker study and another in Serrana, a Brazilian town of 45,000 people, were completely vaccinated, with serious illness and deaths falling after they were inoculated.
Chile, on the other hand, experienced a resurgent epidemic after vaccinating more than a third of its 19 million people — one of the world's highest rates, but not quick enough to avoid the spread of the violent form sweeping Latin America.
"The earliest group of people vaccinated in Chile are old people. Less than 15 million of doses given to Chile means only 7 million people can get our shots. That equals to only 36% of a population of 19 million," said Yin. "It's normal that the country sees a resurgence of infections as social activities increase among the younger people who are mainly not inoculated."
According to Yin, 89 percent of CoronaVac vaccine recipients in Chile were safe from severe Covid, which necessitates intensive care. Due to virus variations, the vaccine's defence may differ from place to place, but Sinovac's shot appears to be holding up well against the latest mutations of concern, he said.
The ability of all Covid vaccines to prevent or deter live virus transmission is a matter of prime concern. Sinovac does not yet know whether its shot, a conventional inactivated vaccine, will minimise the virus from being contracted in the first place, according to Yin, but the fact that it is preventing severe disease and death is more significant.
In Israel, the mRNA shot manufactured by BioNTech SE and Pfizer Inc. was found to be more than 90% effective in preventing transmission. Though non-mRNA vaccines are unlikely to be as successful as Sinovac's shot in preventing transmission, the growing body of evidence that it does is a blessing to China's goal of supplying the developing world in order to expand its reach and status. The Chinese vaccine developers, due to widespread criticisms of the vaccination, did not disclose the adverse effects of the vaccine like the Western and Indian developers, who were more transparent.
"The results from real world application and the scientific data we have from clinical trials will allow the world to judge our vaccine comprehensively," said Yin. "We encourage our partners and governments in countries where our vaccine is being used to release such data as soon as possible."
Indonesia was one of the first countries to put their faith in a Chinese vaccine. President Joko Widodo became the first major world leader to obtain the Sinovac shot in January, in an effort to calm domestic and international suspicion. Since then, the largest economy in Southeast Asia has given out more than 22 million doses, mainly of Sinovac, in an effort to achieve herd immunity for its 270 million citizens by the end of the year.
"The minimum efficacy rate should be above 50%, so beyond that, the best vaccine is the one you can get as soon as possible, as every shot given can prevent deaths," Health Minister Sadikin said. "It isn't only about getting the highest efficacy rate, but inoculating people quickly."
Though cases have increased in neighbouring Malaysia and Thailand, Indonesia's rate of new infections and deaths has remained stable since a January peak. But, with the country's vast population still largely unregulated, Sadikin cautioned that the upcoming Eid holiday could see cases rise by as much as 60% as people gather with family and travel home despite government restrictions.
Vaccines' ability to control a disease in the real world can be higher than in clinical trials, according to Helen Petousis-Harris, a vaccinologist at the University of Auckland.
"In my experience, we often fail to predict the overall impact of vaccines, something that can only be seen in the real world after widespread use," she said. "Reducing the bulk of disease is not only essential to save lives but also to reduce the chances of problematic variants appearing."