People wearing face masks are seen in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)

A man wearing a face mask walks in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)

A woman wearing a face mask walks in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)

A man wearing a face mask walks in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)

A woman wearing a face mask walks in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)

People wearing face masks walk in the Georgetown neighbourhood in Washington, D.C., the United States, on Oct. 30, 2020. The total number of COVID-19 cases in the United States surpassed 9 million on Friday, according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. U.S. COVID-19 case count rose to 9,007,298, with the national death toll reaching 229,293, as of 3:24 p.m. local time (1924 GMT), according to the CSSE. (Photo by Ting Shen/Xinhua)