Shenzhen had administered 3.07 million doses of COVID-19 vaccines to 2.41 million residents as of 4 p.m. Friday, now having the largest number of COVID-19 vaccine recipients among 21 prefecture-level cities in Guangdong Province, SZTV reported.

The province had administered around 10.19 million doses by Friday and can administer a maximum of 1.4 million doses per day, Xinhua quoted the provincial health commission as saying Sunday.

So far, the city boasts a daily vaccination capacity of 270,000 doses with a total of 591 designated COVID-19 vaccination clinics, including 493 fixed vaccination clinics, 40 mega centers, large to medium-sized temporary vaccination sites, and 58 temporary vaccination sites for organizations.

Citizens' willingness to get COVID-19 vaccines is on the rise as Shenzhen's mass vaccination campaign is in full swing.

During the three-day Qingming Festival holiday, a number of large and medium-sized temporary vaccination sites started operations in Shenzhen, according to the city's health authorities.

On Sunday, the COVID-19 vaccination site in Longhua Culture and Sports Center officially opened, providing 1,800 doses of free vaccines without citizens even having to make an appointment online.

Guangming District has also recently opened five large and medium-sized temporary vaccination sites, which offer services from 8 a.m. to 8 p.m.

Data from the National Health Commission show that 139 million doses of COVID-19 vaccines had been administered in China as of Sunday.

Zhong Nanshan, China's top respiratory disease expert, recently said in an interview that China is currently at a critical moment.

Although China ranks second in the world in number of COVID-19 vaccine recipients, due to its large population base, the vaccination rate in China is only 4 percent, Zhong said.

According to Zhong, it is expected that 40 percent of Chinese people will be vaccinated by the end of June or July this year.

He pointed out that China's COVID-19 preventive and control efforts are made with a reason, that is, to buy time for mass vaccination. China will be in danger if it waits till other countries achieve herd immunity.

Gao Fu, director of the Chinese Center for Disease Control and Prevention, said the hope is that by the beginning of 2022, or even by the end of this year, China will have achieved a vaccination rate of between 70 percent and 80 percent and, the country will then basically achieve herd immunity.