Updates on imported cases:
In the last two days Beijing had 8 new confirmed cases, 7 were imported from Italy. Two Chinese nationals returning from Italy took fever medication and lied on their health declaration forms. Criminal investigations underway.
There were many imported cases who took transfer flights after landing in China.
Chinese aviation authority needs to act fast. Require all inbound flights to have no adjacent seats occupied at the same time. This will make quarantine easier, increase travelling cost and cut down inbound passengers. International-to-domestic transfer flights should be banned. Passengers need to be quarantined as they land in China.
Also in the last three days Gansu reported 28 new imported cases from Iran. About 300 Chinese nationals were flown back from Iran on chartered flights to Lanzhou, Gansu's capital. Even if only half of the new cases were from those flights, we're looking at a 5% attack rate. Some of them were students from religious schools in Qom, other were business people from the rest of Iran. Of course not a representative sample, but it's probably not order of magnitude wrong. We still need antibodies tests but the current widely shared guesstimate is that the attack rate in Wuhan was about 1% before the lockdown, and Wuhan had the rest of China to help. Iran is lost. I feel so sorry for them.