This is a time families and friends count the days to arrivals from Britain and long-awaited reunions, especially with holidaying students. The authorities would not lightly get in the way of those. But, with a surge in mutated coronavirus infections forcing the country to be relisted as extremely high risk, the government had little choice but to once again ban all flights from there from tomorrow, leaving thousands stranded. Public health comes first, not to mention the need to safeguard prospects sooner or later of border reopenings with the mainland and Macau.

With Chief Executive Carrie Lam Cheng Yuet-ngor in Beijing for centenary celebrations of the Chinese Communist Party, border reopenings could be on her mind. But Hong Kong will need to demonstrate sustained control over new infections. In that respect, passengers from Britain pose a heightened risk, with it reporting more than 20,000 new cases on Monday. Moreover, the more infectious Delta variant is prevalent. Hopefully, while the window remains open to flights, authorities will tighten airport health checks.

The coinciding of the summer holiday with the virus resurgence in Britain comes at a critical juncture for Hong Kong’s efforts to prevent another major community outbreak. If that were to happen, border reopenings with our neighbours would remain distant prospects. Economic recovery depends so much on the mainland and the Greater Bay Area that infection control must be the priority, whatever it takes. Top mainland respiratory expert Zhong Nanshan believes Hong Kong and the mainland may be able to reopen their border for quarantine-free travel as early as next month if conditions to do so safely are met. So far, Zhong said, Hong Kong had done well to prevent a community spread of the Delta variant.