26th February 2023 – (Hong Kong) The world has moved into the post-epidemic era, and Hong Kong has lifted the vaccine pass, the ban on gatherings, and even the quarantine order. However, Hong Kong will become the only city in the world that legally requires its citizens to wear masks outdoors starting tomorrow. This is because Macao announced the cancellation of the outdoor mask order starting tomorrow (27th). The Macao government has abolished the rule of wearing masks outdoors starting tomorrow, and even indoor places are only subject to the discretion of the person in charge, with no law to enforce it.

Dr. Siddharth Sridhar, a Clinical Assistant Professor at the Department of Microbiology of the University of Hong Kong, stated in a Facebook post today (26th) that Hong Kong is currently the last place in the world where masks must be worn in all public places. He believes that the Hong Kong-wide mask order should be left to the discretion of citizens.

According to Dr. Sridhar, universal masking has been a recognisable feature of public life in Hong Kong over the last three years. Most other local COVID control measures have been dropped, which makes the mask mandate stand out even more. So, it is natural to wonder: how much longer do we need to wear masks? This question asks two different things: a) Are masks helping Hong Kong’s public health at this stage of the pandemic? b) Do masks need to be mandatory? People often conflate these two questions, but they are not the same. Proper mask wearing can be useful (even essential) in certain situations, but that does not automatically make mask mandates necessary.

The Hong Kong public’s first response to the COVID-19 1st wave in 2020 was to put on masks. Even before it became mandatory, levels of mask usage were very high. Levels of both COVID-19 and other respiratory viruses dropped to very low levels in the next two years, although it is difficult to separate the exact contribution of universal masking from myriad public health interventions such as social distancing, school closures, border controls, isolation/quarantine measures, etc. We had a winning formula, and responsible masking was part of it. Laboratory studies in Hong Kong provided fresh mechanistic insights to support the hypothesis that masks work, to a certain extent, in curtailing transmission of COVID-19 and other respiratory viruses.

However, Omicron brutally exposed the weakness of masks. Hong Kong has experienced wave after wave of COVID-19 in 2022 despite high levels of masking. This was accompanied by healthcare collapse and one of the highest death rates globally. One of the simple reasons is that we cannot wear masks all the time. Masks must come off at home, in restaurants, and in work pantries. Even when people wear surgical masks diligently, the fit around the mask isn’t perfect, and contaminated air may seep through. And so, despite face coverings, much of the population has now been infected with COVID-19. However, this immunity itself offers short term but robust protection against COVID-19.

Adherence is a major roadblock to evaluating masks in the real world. Two randomised controlled trials on mask usage to reduce COVID incidence in Denmark and Bangladesh were plagued with low adherence to the mask intervention. Consequently, the measured benefits of masking in these trials were very modest at best. A recent Cochrane meta-analysis had a similar conclusion, but it has been criticised for including mainly older pre-COVID studies. So even though masks are widely perceived as effective in Hong Kong, getting to the truth of the matter is very complicated. All in all, it appears that masks alone aren’t going to entirely prevent surges of illness due to respiratory viruses, although they might attenuate the size of these outbreaks.

While high-risk individuals in high-risk settings should continue to wear masks, it may not be necessary to enforce mask mandates in most public settings except for healthcare areas.

Ultimately, responsible masking should be left to the discretion of citizens, who have been following this practice since the early days of the pandemic. Dr. Sridhar added that as we navigate this new era, it is important to strike a balance between public health and personal freedom. It is also important to continue to monitor the situation and adjust policies accordingly as new information emerges.

In conclusion, Dr. Sridhar asked 3 questions: So, is it reasonable to advise continued mask wearing by high-risk individuals in high-risk settings? Yes. Is it reasonable to make mask wearing optional in most public settings except for healthcare areas? Yes.Is it reasonable to trust members of the public to take their own decisions on responsible masking, which they have done since the early days of the pandemic? Yes.

Meanwhile, the Health Secretary has recently made a decision to exercise the powers granted by the Prevention and Control of Disease (Wearing of Mask) Regulation, Cap. 599I, to extend the mandatory use of masks in various public areas in Hong Kong. This extension applies to public transport, MTR paid fare areas, public places, and premises governed by Cap. 599F for a period of 14 days, ending on 8th March, 2023.

The decision implies that Hong Kong citizens are still obligated to wear masks until the aforementioned date, and if government does not extend the validity of the Prevention and Control of Disease (Wearing Masks) Regulation, the mask order will automatically lapse at midnight on 31st March.