Along with climate change come mosquito-borne diseases. Is Hong Kong ready for a public health emergency?

Months after Hong Kong was ranked by Bloomberg as the economy with the world’s most efficient health care, its public health system is caught in a crisis. More than 100 medical staff protested about the manpower crunch and ward overcrowding amid a winter flu surge in January, with many holding placards that sent the desperate message: “Breaking point”. This has been followed by a spike in measles infections since mid-March, and a shortage of vaccines.

More alarmingly, the next public health crisis might already be brewing. The growing effects of climate change on Hong Kong, if not addressed head-on and soon, with more innovation, will take a significant health toll and put further strain on the city’s overloaded public health sector.

Climate change is more than an environmental problem. The Lancet, a leading medical journal, has described climate change as a “public health emergency”. Last year was Hong Kong’s third hottest on record, with 36 days at 33 degrees Celsius or above.

The rising number of hot days is likely to trigger more cases of heat-related illnesses such as heatstroke and aggravate chronic conditions, including cardiovascular and respiratory diseases, driving a surge in demand for hospital services. A Chinese University of Hong Kong study found that during the hot season, hospital admissions increased by 4.5 per cent for every increase of 1 degree above 29 degrees Celsius.

The buzz of mosquitoes during warm Hong Kong nights is not just annoying. It should also sound warning bells that disease-carrying mosquito species like Aedes aegypti are growing faster and surviving longer. Climate change shortens the incubation period of pathogens causing dengue fever, which infects as many as 400 million people around the world every year. While dengue is not endemic in Hong Kong, a record 163 cases were reported here last year.