Intended for healthcare professionals


When Hong Kong’s “dynamic zero” covid-19 strategy met omicron, low vaccination rates sent deaths soaring

BMJ 2022; 377 doi: (Published 13 April 2022) Cite this as: BMJ 2022;377:o980
  1. Arisina Ma, geriatrician and former president of the Hong Kong Public Doctors’ Association1,
  2. Jane Parry, public health analyst and writer from Hong Kong2
  1. 1Nottingham, UK
  2. 2Hamilton, Ontario, Canada

How did Hong Kong go from being an exemplar of covid-19 control, to the place with the worst covid-19 death rate in the world?

It was a shocking image, unlike anything we had seen before in a Hong Kong hospital,1 even during the devastating SARS outbreak in 2003. A photograph taken on the accident and emergency ward at the Queen Elizabeth Hospital showed three older patients, at least one visibly conscious. Tucked around their beds were six filled body bags on stretchers. The photo circulated on social media on 11 March 2022 and was verified as being taken at the hospital earlier that month. Hong Kong’s mortuaries were full, and clearly no one had a plan to deal with this many dead bodies.

Two weeks before, Hong Kong’s hospitals were already showing signs of being overwhelmed and unprepared for the volume of covid-19 patients—or the resulting deaths. Dozens of mostly older patients were parked in a temporary triage area outside one hospital, some were left up to 24 hours, exposed to the elements in one of the coldest weeks of the year.2 There were other horror stories: infants separated from their parents and admitted to hospital alone3; older patients in a makeshift, government operated isolation facility left for two weeks without bathing4; foreign domestic workers who tested positive for covid-19 turfed out by their employers, sleeping rough, and unable to access government isolation facilities.5

At the end of January 2022, Hong Kong’s confirmed cumulative covid-19 death toll stood at 205 for the entire pandemic.6 Within two months, the toll was 7945 and rising, predominantly among the older population, most of whom were unvaccinated.7

How did Hong Kong go from being an exemplar of covid-19 control, to the place with the worst covid-19 death rate in the world?89 How did things in this highly sophisticated city of 7.4 million people, two years into the pandemic, and a year after the arrival of covid-19 vaccines, go so terribly wrong?

As disturbing as the images from Queen Elizabeth and other hospitals were, the sight of an overwhelmed health system was no surprise to those working within it. They had been warning for years, and especially once covid-19 arrived, that there was no surge capacity at all in the public hospital system. In this latest, deadly wave of covid-19, there are clear signs that quality of care has deteriorated.10

Throughout 2021, despite an ample supply of vaccines, Hong Kong’s vaccination rates remained stubbornly low, especially among the older population. Many Hong Kongers think the vaccine drive has been tainted with politics, with both subtle and overt attempts to push the Sinovac CoronaVac inactivated vaccine produced in mainland China, which was offered alongside the Pfizer-BioNTech Comirnaty mRNA vaccine. The government has pushed forward a series of “semi-compulsory” vaccination measures, such as prohibiting unvaccinated civil servants and hospital authority employees (without a covid-19 vaccination medical exemption certificate) to work, and restricting the opening hours of restaurants with unvaccinated employees. The overall population vaccination rate gradually grew to 70%, but even by the end of February 2022, with omicron raging through the population, less than 20% of older care home residents were fully vaccinated against covid-19.11 The rate for community dwelling seniors was 45%, but this is still far lower than in neighbouring countries, such as Singapore (approximately 95%) and South Korea (approximately 90%).11

The level of vaccine hesitancy was surprising in a city with almost no anti-vax movement and a population of notoriously early adopters of any new technology. It belied a general lack of public trust in the government and the failure of the vaccination campaign to counter misinformation about covid vaccine safety. The government delegated the risk-benefit conversation about covid vaccines in the older population to family doctors, telling those with pre-existing conditions (which, as in most countries, is the majority of older adults) to consult their doctor first. Many doctors in Hong Kong are hesitant to stand up for vaccination when facing challenges from their patients on vaccine safety. They are cautious about comparing the performance of the two available vaccines in case they are held liable for any adverse effects. What was originally a scientific question has become a highly political one in Hong Kong.

Moreover, the decimation of grassroots and community organisations in an increasingly authoritarian political environment, including the collapse of the city’s network of district councillors, meant that there was no viable infrastructure to mobilise the public and get them behind a mass vaccination campaign.1213 In less turbulent political times, district councillors and grassroots organisations would routinely organise flu vaccination drives for older people in their community.

By the end of 2021, as most of the world was moving towards various “living with covid” strategies, the Hong Kong government doubled down. Instead of moving to mitigation and protection of the most vulnerable, it aligned itself entirely with China’s zero covid policy, further tightening border controls and imposing even stricter social distancing and gathering restrictions on the population. Hong Kong has always had a good reputation for being dynamic and flexible, but by the time the omicron variant hit, the strict contact tracing and isolation measures adopted up to that point were no longer able to control the spread of such a contagious variant. It appeared that senior public health officials were not the ones leading this battle. Instead, the chief executive of the government took the lead, and different political powers joined the game. Anyone in Hong Kong who openly challenged the mainland government’s official position to adopt the so-called dynamic covid-zero strategy was labelled as having ulterior motives.

Of those older people in Hong Kong who are now vaccinated, a substantial number are vaccinated with the CoronaVac inactivated vaccine,14 which has been shown to have lower effectiveness compared to the Comirnaty mRNA vaccine, with a clear tendency towards decreased efficacy with age.15

In a population almost completely naive to covid-19 infection, with vaccination rates too low to blunt the impact of omicron, and health and adult social care systems entirely unprepared, this lack of an effective, evidence based plan has proven fatal to thousands of people and created misery for millions. Public health and infectious disease epidemiology experts, including those who are official advisers to the government, could only stand by and watch as their advice wasn’t heeded by ministers.16

These are dark times for the city of Hong Kong. We can only hope that, in time, rational evidence based policy will prevail. It will be too late, however, not only for those who died from covid-19, but the countless patients unable to access regular medical care during this time, and for the city’s angry, exhausted, and helpless healthcare workers.17


  • Competing interests: None declared.

  • Provenance and peer reviewed: Commissioned; not peer reviewed.