In this photo released by Xinhua News Agency, a woman registers information for COVID-19 vaccination at the Jingcheng Hospital in Ruili city in southwestern China's Yunnan Province, April 1, 2021. The Chinese border city hit by a fresh outbreak of COVID-19 this week began a five-day drive Friday to vaccinate its entire population of 300,000 people. (Chen Xinbo/Xinhua via AP)

ADDS VACCINE MANUFACTURE’S NAME - In this photo released by Xinhua News Agency, a medical worker administers a Sinopharm's COVID-19 vaccine at the Jingcheng Hospital in Ruili city in southwestern China's Yunnan Province Thursday, April 1, 2021. The Chinese border city hit by a fresh outbreak of COVID-19 this week began a five-day drive Friday to vaccinate its entire population of 300,000 people. (Chen Xinbo/Xinhua via AP)

A woman wearing a face mask to help protect against COVID-19 walks past a tree in bloom on a rainy day in Beijing, Friday, April 2, 2021. A Chinese border city hit by a fresh outbreak of COVID-19 this week began a five-day drive Friday to vaccinate its entire population of 300,000 people. (AP Photo/Mark Schiefelbein)

In this photo released by Xinhua News Agency, residents wearing masks line up for COVID-19 vaccination at the Jingcheng Hospital in Ruili city in southwestern China's Yunnan Province, April 1, 2021. The Chinese border city hit by a fresh outbreak of COVID-19 this week began a five-day drive Friday to vaccinate its entire population of 300,000 people. (Chen Xinbo/Xinhua via AP)