In 2021, China continued to address the COVID-19 pandemic in China with a Zero-COVID policy that significantly reduced transmission of COVID-19 through large scale lockdowns and testing. The Convidecia and Sinopharm vaccines were approved for general use in China in February 2021. China achieved a record number of 55 space missions in 2021, including the development of the Tiangong space station and the first Chinese craft to land on Mars. Concerns about declining birth rates caused the national government to replace its two-child policy with a three-child policy in May 2021. In the Chinese zodiac, 2021 was the year of the Ox and associated with the Wuxing element of metal.