A medical worker collects a swab sample from a teacher for COVID-19 test at a school in Karachi, Pakistan, on Sept. 14, 2020. After a consistent drop in new cases, the Pakistani government has announced to reopen educational institutes in phases from Sept. 15. (Str/Xinhua)

A medical worker collects a swab sample from a teacher for COVID-19 test at a school in Karachi, Pakistan, on Sept. 14, 2020. After a consistent drop in new cases, the Pakistani government has announced to reopen educational institutes in phases from Sept. 15. (Str/Xinhua)

A medical worker collects a swab sample from a teacher for COVID-19 test at a school in Karachi, Pakistan, on Sept. 14, 2020. After a consistent drop in new cases, the Pakistani government has announced to reopen educational institutes in phases from Sept. 15. (Str/Xinhua)

A medical worker collects a swab sample from a teacher for COVID-19 test at a school in Karachi, Pakistan, on Sept. 14, 2020. After a consistent drop in new cases, the Pakistani government has announced to reopen educational institutes in phases from Sept. 15. (Str/Xinhua)