Medical workers say goodbye to each other after a 14-day quarantine in Anji, east China's Zhejiang Province, April 18, 2020. The last batch of medical workers from Zhejiang Province, who aided the fight against COVID-19 in Hubei Province, finished their 14-day quarantine. (Photo by Cui Li/Xinhua)

Medical workers say goodbye to each other after a 14-day quarantine in Anji, east China's Zhejiang Province, April 18, 2020. The last batch of medical workers from Zhejiang Province, who aided the fight against COVID-19 in Hubei Province, finished their 14-day quarantine. (Photo by Cui Li/Xinhua)

A medical worker takes off her face mask after a 14-day quarantine in Anji, east China's Zhejiang Province, April 18, 2020. The last batch of medical workers from Zhejiang Province, who aided the fight against COVID-19 in Hubei Province, finished their 14-day quarantine. (Photo by Cui Li/Xinhua)

Medical workers wave goodbye to each other after a 14-day quarantine in Anji, east China's Zhejiang Province, April 18, 2020. The last batch of medical workers from Zhejiang Province, who aided the fight against COVID-19 in Hubei Province, finished their 14-day quarantine. (Photo by Cui Li/Xinhua)