People wait to receive COVID-19 vaccines at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)

People stay at an observation area after receiving COVID-19 vaccination at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)

People stay at an observation area after receiving COVID-19 vaccination at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)

Two medical workers prepare a dose of vaccine at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)

People receive COVID-19 vaccines at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)

A woman registers her information before receiving COVID-19 vaccine under the guidance of a staff member at a temporary vaccination site in Kunming, southwest China's Yunnan Province, April 12, 2021. The temporary vaccination sites is newly set at a gymnasium in Guandu District of Kunming, with daily inoculation capacity of about 5,000. (Photo/China News Service)