How long do close contacts in Lanxi need to be isolated?

According to the relevant regulations, the second close contact person was subjected to centralized isolation medical observation for 7 days. If the COVID-19 nucleic acid test results are negative in the first 7 days, and the COVID-19 nucleic acid test results of its close contacts are also negative, the centralized isolation medical observation will be lifted. The first two nucleic acid tests of close contacts were positive, and patients with close contacts were managed as close contacts.