A staff member checks the quality of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member checks the quality of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member makes nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member checks the quality of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff makes a nucleic acid extraction kit at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member makes nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member prepares reagent for quality checking of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member checks the quality of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member checks the quality of nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member shows a nucleic acid extraction kit at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)

A staff member transports nucleic acid extraction kits at Chengdu Bio-Base Technologies Co., Ltd. in Chengdu, southwest China's Sichuan, Feb. 10, 2020. Since the outbreak of the new coronavirus epidemic, the technical staff of Chengdu Bio-Base Technologies Co., Ltd. have returned to work quickly to produce the nucleic acid extraction kits for sample testing to help prevent and control the epidemic. (Xinhua/Liu Kun)