Apart from local high- and medium-risk areas, lockdown and control measures can also be imposed on places where COVID-19 infections or their close contacts have been to, the Shanghai Health Commission said on Tuesday.

Residents in these places will undergo two or seven days of home quarantine plus one to two weeks of self-health management, based on epidemiological investigation and risk evaluation.

They must also take multiple nucleic acid, or polymerase chain reaction (PCR), tests during the quarantine period.