Coronavirus: Hong Kong must remain on guard against a fourth wave of Covid-19

The weeks after the Universal Community Testing programme brought a decline in Covid-19 cases in Hong Kong, with parts of the transmission chain cut off by the programme, together with enhanced surveillance measures adopted by public hospitals and clinics. While the numbers remained low in the past two weeks, domestic cases have kept popping up at an average of one per day lately, suggesting that hidden transmission chains continue to exist.

According to the Hong Kong University School of Public Health’s real-time dashboard for Covid-19 in the city, the effective reproduction number for the coronavirus – the average number of people infected by one patient – lingered at 0.5 to 0.6 for the past month. This suggests the outbreak is currently under control with two patients required to infect one person. That being said, the figure has failed to significantly dip any further – unlike after the second wave died down – and is itself retrospective in nature, lagging the real-time trend by one to two weeks.

This indicates that we have to take pre-emptive action if we see signs of the outbreak rekindling, as there is no well-established threshold of the number of cases which is considered acceptable. Hong Kong’s ring-fencing strategy aims to achieve a zero Covid-19 status, not a few cases each day lingering for weeks (“When will Hong Kong’s fourth wave of Covid-19 hit? Very soon, experts warn”, October 5).

Many aspects of the economy, in particular the catering and retail industries, came to a grinding halt when the outbreak intensified. The continued discovery of cases renders further relaxation of social distancing measures difficult, further delaying a return to business as usual. The best way to allow businesses to reopen is a determined effort to eliminate infections within the community by upholding strict social distancing measures, enhancing community surveillance and rigorous contact tracing.

Several countries such as New Zealand, Australia and Vietnam are on track to eliminate their recent case rebounds, and Hong Kong can follow in their footsteps towards achieving zero domestic cases.

We need solidarity, determination and resilience in the ongoing pandemic, which has proved to be both a public health and an economic crisis. We prefer a decisive approach on curbing infections rather than not prioritising it until there is a large rebound, followed by more severe restrictive measures. Winter is coming, we will brace ourselves and overcome the challenge.

Dr Fu Hong Chung, Kowloon City