There were 106 cases in the week that I published the first in a series of articles outlining the potential options for management of the evolving Covid epidemic in Hong Kong. I suggested that the biology of Omicron would force a strategic shift in Hong Kong's public health policy. In the second article I offered a proposal for what a Plan B may look like. In part three, I explained why mitigation was a better option for population health than dynamic zero Covid and in the previous article I asked how we should best proceed based on the assumption that the goal is to maximise the health and well-being of the population of Hong Kong.
In this article, I ask why the clear advice of Hong Kong’s public health, epidemiology and virology experts has not driven a science-based strategy. I consider what the long-term implications are likely to be for population health in Hong Kong.
What is the best strategy for Hong Kong?
In the previous article I divided our strategic goals into short term and long term.
In the short term, I argued that the focus should be on minimising loss of life. Thanks at least in part to the visit from Professor Liang Wannian, who echoed concerns which had been expressed by local public health experts, universal testing was postponed and with support from China, capacity in emergency hospital care was increased. Hong Kong also obtained anti-viral medications. As a result, although the health system remains under stress, the acute crisis resulting in overloaded hospitals is coming under control.
In the longer term I argued that the only rational policy for Hong Kong is a transition to living with Covid. When considering the option of returning to zero or dynamic zero Covid, I made the following comments:
‘I can think of no scenario in which this would be in the best interests of population health in Hong Kong. In the short term it would do even more harm than it already has by diverting energy and resources from policies which are most effective in minimising loss of life. In the long term it will damage population health through the inevitable social and economic damage of public health restrictions on our international city.’
What is the consensus of medical expert opinion?
A recent report by the School of Public Health of the University of Hong Kong included the following statement:
‘Focusing first on purely public health and scientific grounds alone, we are increasingly convinced that the safest strategy for HK would be a controlled transition towards endemicity sooner rather than later.’
Research internationally shows that hybrid immunity, that is a combination of vaccination and infection with Omicron, gives the best protection against reinfection, hospitalisation and death from other variants of Covid. The epidemiological model from HKU suggests that at least 60% of the population have already been infected and are therefore immune. Omicron BA.2 is milder than previous variants and as such it may well be safer to develop immunity in the remaining 40% of our population now with a combination of vaccination and Omicron infections rather than to wait for future variants.
In addition to reducing future potential risks, transitioning to living with Covid now offers a quicker return to a more normal life with associated benefits to both mental health and to the economy. The latter being the most important driver of long-term health in populations.
What would a positively communicated transition to living with Covid look like?
- Define and positively communicate a plan
- Explicitly state the goal: transition to living with Covid
- Cancel compulsory universal testing
- Announce unrestricted opening of borders based on a negative on arrival PCR
- Announce unrestricted return for in-person school
In a previous article suggesting options for Plan B, the first item on my proposed agenda was positive communication. Defining the strategy and managing the narrative is a key component of epidemic control. On an individual level, lack of control and uncertainty are the key drivers of stress and anxiety. From a business perspective, uncertainty prevents planning and drives capital, both human and economic, to alternative sources of greater certainty. Public health communication should be positive, reliable, acknowledge uncertainties and adapt to evolving evidence.
2. Define the strategy
Defining the strategy of a transition to living with Covid has the advantage of creating a roadmap towards a more certain future. This strategy is the only rational policy from the perspective of population health. A transition to living with Covid is clearly supported by science and this strategy can be shaped by lessons taken from other countries who have effectively made this transition.
3. Cancel compulsory universal testing
Once the strategy has been defined, cancelling the CUT (Compulsory Universal Testing) would have the advantage of providing both reassurances over the fear of forced quarantine and the ability to transfer both energy and resources to more effective use.
4. Open borders
The borders should be opened without restrictions. A PCR negative Hong Kong resident arriving at the airport has a significantly lower risk of Covid than any Hong Kong resident chosen at random from within the city. In Hong Kong if that individual had tested positive then they would isolate at home for seven days and assuming that they were then RAT negative they would be free to move around the city as normal. Placing a greater burden on a PCR negative resident than a RAT positive resident has no rationale or logic in science. Like 21-day quarantine previously, this policy is not prudent, it is actively doing harm.
5. Unrestricted in-person schooling
Education of the young is one of the key functions of a developed society. Education is more than Zoom classes. As part of their global development, children need to develop social and language skills in addition to physical competencies. In-person schooling should be undertaken as soon as possible with minimum barriers to entry. I explain below why mandates around vaccinating children cannot be justified based on either scientific or ethical principles.
What did the government announce?
In terms of actions, the government announcement of a road map for relaxing social distancing was a nod towards living with Covid. Whilst it is possible to debate the timing of some of the measures, there is certainly a trend towards relaxation including a return to school and some relaxation of border control. There was a postponement rather than cancelling of the CUT and whilst there was some relaxation of border controls, this was done in such a way that it minimised potential benefits.
So has Hong Kong defined a clear strategy?
Answer: No and therein lies the problem
The most important priority in any public health strategy is to define the public health goals, develop strategies to best achieve those goals and then positively communicate the actions needed to achieve them. This involves a recognition that the strategy may need to adapt to evolving evidence.
The failure to cancel Compulsory Universal Testing is a good example of failing to adapt to evolving evidence. Even if we were to define a strategy of zero Covid, universal testing at this stage of the epidemic wave would be an expensive and unnecessary performance. It would require repeated rounds of testing, the isolation of large numbers of non-infectious people and by the most optimistic projections it may get us to our destination one to two weeks earlier than without. How long we would stay at zero is a different question. Considering that the border remained closed when we had months of no local transmission and looking only at the infectivity of Omicron BA.2 and the epidemiology of the infective waves in Hong Kong and China, it seems very unlikely that even if we were to reach zero Covid it would lead to an open border more quickly than if we moved to endemicity.
‘China has proven its ability to eliminate and the best strategy likely remains to continue elimination over the winter. The increasing transmissibility of the Omicron BA.2 variant means that continued elimination will be a challenge even for China. In my opinion, considering the availability of new anti-viral drugs and the proven effectiveness of vaccination I think it is most likely that China will begin to transition as early as Spring 2022.’
The potential for China to manage an effective transition will be influenced by evolving data on the effectiveness of vaccinations. The results published this week by the University of Hong Kong will be very important. Although the study confirms two shots of BioNTech to be more effective than two shots of Sinovac, the data confirms that Sinovac is an excellent vaccine, especially with a booster dose. One way of thinking about this is that Sinovac vaccination is a three-shot series. The Hong Kong data showed both vaccines (including boosters) to be 98% effective against severe disease and death. Professor Cowling has an excellent thread on the vaccine study here.
If our actions point to living with Covid does it matter what we call it?
Answer: Yes it very much matters how we define our strategy
The Hong Kong Covid response has been defined by a mixed narrative rather than a clear strategy. The continued focus on herd immunity by vaccination is one good example. Basing our policies on a percentage of the total population being vaccinated makes no scientific sense. It is one of our policy errors. Vaccinations are not as good at preventing Covid infections but they are fantastic at reducing the risk of people becoming seriously ill or dying.
'Explain to people we are not trying to get herd immunity, we are trying to stop Granny dying. The disease will come in, we can’t stop it'
Fig 1. Graph courtesy of Joel Chan @kjoules 58% of the currently eligible but unvaccinated population of Hong Kong are over 60 years of age. 96% of deaths have occurred in those over 60.
The focus on the biologically impossible concept, of herd immunity via vaccination alone, led us to drive vaccination rates in the young rather than to address the elephant in the room, which was the unvaccinated vulnerable. As I argued previously, targeted and time-limited mandates focused on vaccinating the vulnerable elderly were justifiable to protect the health system. Mandates targeting the young are not. I am ultra pro-vaccine but there are no scientific or ethical justifications to coerce vaccination in children. Vaccination should be a choice other than in the extreme situation of population threat. We had such a situation with the elderly and we failed to act. Setting the criteria for in-classroom teaching based on 90% vaccination rates makes no scientific sense. It is a continuation of the failed ‘herd immunity by vaccination’ narrative. It has taken root at least in part because of a lack of clarity in our strategy.
This is more than an academic debate with differences in expert opinion. All public health interventions are ultimately a balance between the costs of the disease in both human and economic terms and the costs of the public health measures to both the individual and the population. We must protect the vulnerable, both young and old. It is a balance. The Hong Kong Covid strategy has been based upon the illusion of the total elimination of all risk. Risk can never be eliminated, it can only ever be mitigated. Every public health intervention carries a cost and unintended consequences. I am not advocating for open borders to make holiday travel and life easier for expatriates. Excessive focus on the risks of the disease ignores the potential impact on the rest of the population. Pandemics always aggravate the impact of social inequality. The poorest children fall behind in education and the lowest-paid workers are most likely to be both unemployed and impacted (physically and psychologically) by the disease. In population terms, poverty and social inequality are the greatest drivers of poor health. The damage caused to population health in Hong Kong at this stage of the epidemic will be significantly greater from the economic impact of the public health measures than from the disease itself. Death in epidemics is a lagging indicator. Unfortunately, the majority of the future mortality in Hong Kong is already baked in from previous policy decisions, especially the failure to vaccinate the vulnerable elderly. It is important that the spread of the infection into the currently non-immune fragment of the population is mitigated to a level that does minimal harm. Vaccinating the vulnerable, drug treatment and targeted social distancing measures are the key tools in this regard. We must ensure that the health system is not overloaded but equally we must consider the negative impact of the public health measures on population health, especially the health of the most vulnerable both young and old.
Why have we not defined a strategy?
In my last article I asked why Hong Kong continued with zero Covid without any form of an exit plan. The answer was politics and that remains the crux of our problem.
‘In summary political imperatives failed to recognise the different structural capacities and threats in Hong Kong and China.’
The failure to define a strategy has resulted in an attempt to walk a tight rope, balancing on the one side, science and evidence, and on the other a political constituency seemingly unable to understand the most basic concepts of biology.
As previously explained, China has a long tradition of public health and a body of world-class public health expertise. We know that China’s leading epidemiologist agreed with the opinions of Hong Kong’s own public health experts. Despite this Hong Kong continues to ignore the overwhelming consensus of our own public health and medical expertise.
In order to minimize harm to population health we must recognize and accept that Hong Kong and China are at different stages of our respective epidemics, facing unique and different challenges and capacities. In order to minimise harm to the most vulnerable members of our community, it is essential that Hong Kong defines and positively communicates an evidence-based public health policy focussed on protecting population health in our city.