A Chinese expert has said data shows vaccination is highly effective for the elderly to fend off severe symptoms and death when infected by COVID-19.

A vaccination regimen consisting of three shots is an ideal immune process, according to Zheng Zhongwei, head of vaccine research and development team of National Health Commission. "It's about 98 percent effective to prevent severe symptoms after three shots, no matter what kind of vaccines you're taking."

Based on the COVID-19 situation in Hong Kong, the mortality rate of the elderly who complete three-shot vaccination drops as much as 74 times compared to the unvaccinated, said Zheng. Even for those who only take one shot, the death rate declines three times compared to those without vaccines.

He added that more than 90 percent of the infected are aged above 60 with underlying diseases.

The elderly face significantly higher risks without vaccination than the younger population. The death rate due to COVID-19 among those aged over 80 is 16.48 percent while the chance of death for patients between 20-59 is just 0.27 percent, according to the Center for Health Protection of Hong Kong.

As of Thursday, over 1.25 billion people in China, or 88.74 percent of the country's total population, had been fully inoculated against COVID-19. More than 215 million of them are aged over 60.

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