BEIJING — Passengers arriving from outside the Chinese mainland and close contacts of COVID-19 patients can be released from quarantine if they test negative for the virus following two separate nucleic acid tests of simultaneously collected nasal and throat samples, according to the latest guidelines for COVID-19 prevention and control.

In principle, the two tests, conducted during their quarantine and when the quarantine is lifted, should use two different reagents and should be carried out by two different testing agencies, according to the guidelines released by the State Council inter-agency task force for COVID-19 response.

Those who are released from quarantine should undergo nucleic acid testing on the second and seventh days after medical observation is lifted, and they are required to keep a close watch on their personal health and avoid gatherings, read the guidelines.