Table 2.

The key events and public health interventions across the four stages in the campaign against SARS-CoV-2 Delta in Guangzhou.

^aPeople self-quarantined and performed nucleic acid tests on the 1st to 7th, 10th and 14th days of quarantine. ^bPeople could only enter but could not exit their own neighborhood and gatherings were strictly prohibited. Nucleic acid tests were performed on the 1st, 4th and 7th days. ^cPeople could only travel between home and working places with negative nucleic acid test results within 24 hours. ^dPrimary close contacts (PCC) referred to people (i) whoever was either in the same space, same workplace or building with infected people; (ii) those who had been with infected people 4 days before disease onset. Disease onset referred to date of symptom onset for symptomatic cases and sampling date of the first positive test result for pre-symptomatic case. ^eSecondary close contacts (SCC) referred to close contacts of PCC. ^fRisk areas included places with (i) >50 cumulative number of confirmed cases and at least one cluster was discovered within 14 days; (ii) cumulative number of confirmed non-clustered cases exceeded 50 within 14 days; (iii) newly reported confirmed cases within 14 days.