The COVID-19 vaccines made by China are doing well in a variety of criteria for the vaccine's effectiveness, according to the chairmen of domestic vaccine manufacturers and other experts.

"There are three dimensions to assess the effectiveness of a vaccine: safety and efficacy, accessibility and affordability. And we make the grade on them all," said Yin Weidong, chairman and CEO of Sinovac Biotech, a major coronavirus vaccine provider for the country and the world.

"The vaccines developed and produced by China's Sinovac and Sinopharm are based on the inactivated virus. It's a more mature method and requires a higher level of bio-safety in production compared with other new technologies like the mRNA route," said Feng Duojia, president of the China Vaccine Industry Association.

"The Chinese vaccines can be stored at temperatures of 2 to 8 C, which makes them easier to store and transport, while the mRNA vaccines require extremely low temperatures, even -70 C," Feng added.

"The side effects in people after taking our vaccines are fewer and lighter than many other kinds of vaccines, mostly muscle aches and light fever, "said Yang Xiaoming, chairman of China National Biotech Group, a subsidiary of Sinopharm.

The Chinese vaccines have reported promising efficacy rates in different countries. For example, the Sinovac vaccine showed 65.3 percent of efficacy in Indonesia, 78 percent in Brazil and 91.2 percent in Turkey. The Sinopharm vaccine had a reported 86 percent efficacy against COVID in the UAE.

"The differences in clinical trial design, sites, populations and statistical methods in different countries contribute to the different results," Feng said.

"Our inactivated vaccine is a whole virus vaccine and contains various antigens. So it's more adaptive when responding to different variants of the virus," Yin added.

This is also true of the Sinopharm vaccine, Yang said. "The vaccine has proved effective in protecting people from seven to eight variants of the coronavirus. We believe our vaccine can protect against the new variant found in the UK and tests on this are underway."

China, as a participant in the WHO-backed vaccine program COVAX, has been at the forefront of vaccine research and development, upholding the role of multilateral cooperation in advancing the equitable global distribution of vaccines.

The United Arab Emirates, Bahrain, Egypt, Jordan, Turkey, Indonesia and Brazil are among the countries that have authorized the use of Chinese COVID-19 vaccines, and over 40 countries have asked to import them.

Responding to numerous demands, China has also made every effort to ramp up vaccine production.

"Eighteen vaccine producers are accelerating expansion of manufacturing capabilities, and China's total annual capacity is expected to reach 2 billion doses by the end of 2021," Feng said. "With more developers getting regulator's approval for their vaccines and building the production capacity, the nation's total capacity will eventually reach 4 billion per year, covering 40 percent of world demand, based on calculations of world population and average vaccination rates."