The omission of a heat-health action plan in Hong Kong’s first five-year plan and latest policy address is causing environmentalists and academics concern, who warn “common sense” is not enough to protect vulnerable residents.
Their comments came as new research from the University of Hong Kong (HKU) found that extreme heat might have contributed to as many as 3,238 excess deaths in the city over the 10-year study period.
In response to queries about the lack of a cross-departmental heat action plan for vulnerable groups, a government spokesman said there were ongoing efforts.
But environmentalists noted that neither the five-year blueprint nor the annual policy address, both delivered by Chief Executive John Lee Ka-chiu in September, included a comprehensive plan for a systemic, overarching heat-health action plan to address urban heat.
A new management system known as the “city brain”, which aims to improve interdepartmental collaboration during extreme weather, was proposed in the policy address.
The World Health Organization outlines eight core elements for heat-health action plans, including governance, early-warning systems, surveillance and outreach.
Greenpeace Hong Kong campaigner Prudence Yeung said: “Including a heat action plan in the policy address or the five-year plan … could ensure heat adaptation and resilience as a citywide priority, and provide a foundation for investment in heat resilience infrastructure, research and public awareness.”
A Greenpeace survey, released in August, found that nearly 80 per cent of low-income elderly people surveyed in Hong Kong reported physical or mental distress during periods of extreme heat. That month the city logged its hottest single day – August 9 – since records began in 1884.
In a study currently under peer review, Professor David Bishai, director of the school of public health at HKU, and other researchers revised figures from research in 2024, estimating that heatwaves in Hong Kong between 2014 and 2023 may have contributed between 1,455 and 3,238 excess deaths.
An earlier estimate was 1,677 excess deaths.
Bishai’s projection was based on demographic data from the Census and Statistics Department, temperature data from the Hong Kong Observatory and relative risks derived from local research.
A simulation was used to estimate heat-attributable deaths under different definitions of a heatwave. These preventable excess deaths had largely gone unrecognised as they were exacerbations of underlying illnesses, rather than heatstroke, which was rare, Bishai said.
“Enacting an action plan in the face of extreme heat can be helpful in reducing death rates … We know that just leaving it to common sense is not working, because we are still seeing these excess deaths during heatwaves,” he said.
“It’s like running a marathon. The heart rate goes up, the blood vessels dilate, blood is shunted away from the brain into the hands and feet so that you can sweat more. And it is a very bad stress test that people’s bodies fail at those ages with those pre-existing conditions.”
Bishai cited Paris, where a heat action plan featuring proactive welfare checks on the elderly was projected to have cut heat-related mortality by around 77 per cent following heatwaves in 2003.
Hong Kong’s heat measures are activated when the Observatory issues a “very hot weather” warning, triggering the opening of temporary shelters in community halls. According to government figures, the 19 shelters that operated overnight on very hot evenings served between 120 and 210 users a day in June and July.
The Labour Department issues heat-stress alerts for outdoor workers – recently revamped following criticism – while the Department of Health provides public health advisories.
