From sam:

This, from Taiwan, has been up before.It helps still to add context and, I hope, some force to stewartb’s post.

From a statistical point of view, the probability of physically encountering the novel coronavirus or of being exposed to infected individuals in large international airports or in the cabins of airplanes is much higher than in homes, workplaces, schools or other public spaces.

https://www.taipeitimes.com/News/editorials/archives/2020/03/22/2003733144

Singapore

“The Ministry of Health (MOH) announced 47 new cases of Covid-19 in Singapore on March 21.

Of these cases, 39 are imported, with 16 of them having a travel history to the UK.”

https://mothership.sg/2020/03/covid-19-uk-imported-cases/

Hong Kong

“Hong Kong confirmed 25 coronavirus cases on Wednesday, the highest number in a single day, most of them coming from overseas, reflecting the new risk confronting the city after its initial success in keeping a lid on infections.”

https://www.scmp.com/news/hong-kong/health-environment/article/3075731/coronavirus-imported-cases-surge-eight-more-test

This suggests that asymptomatic infection is likely to be a major cause of transmission.

“Wu Tangchun, a public health expert at Huazhong University of Science and Technology in Wuhan, who led the study, told Nature, “By our most conservative estimate, at least 59% of the infected individuals were out and about, without being tested and potentially infecting others. This may explain why the virus spread so quickly in Hubei and is now circulating around the world.”

https://www.weforum.org/agenda/2020/03/people-with-mild-or-no-symptoms-could-be-spreading-covid-19/

“Ground zero” my bahookie. What malign stupidity from BBC and Scotsman