What should Shanghai do when it receives a short message from Nanjing?

Avoid going out unnecessarily for the time being.

Received a short message from the Office of Epidemic Prevention and Control, suggesting that you may have been exposed to positive cases in COVID-19 or high-risk areas. You don't have to be too flustered, report to your community in time, temporarily avoid unnecessary going out, and actively cooperate with the development of nucleic acid testing. If it is confirmed that you have no intersection with positive cases or high-risk areas in COVID-19, and the nucleic acid test is negative, you can resume your daily life. "2+ 14": check the negative proof of nucleic acid test within 2 days (48 hours) and conduct daily health monitoring 14 days.

"14+7": that is, 14 days of centralized isolation +7 days of home health observation.