The cold wave starting on 9 Feb 2014 when the minimum temperature dropped to 10.40C may have claimed hundreds of lives in Hong Kong without being aware of by the government nor the general public. We witnessed more than a week’s long cold spell with minimum temperatures as low as 7.30C, well below the average minimum temperature of 150C in early February. Yet another cold wave arrived in Hong Kong in the evening of 18 Feb 2014.
While cold temperatures usually last for only a few days, Hong Kong was caught unprepared by its longest cold spell in 40 years in early 2008, with mean temperatures at 14 °C or below for 24 consecutive days from 24 Jan to 16 February. According to a study conducted in 2013 by the Collaborating Centre for Oxford University and CUHK for Disaster and Medical Humanitarian Response (CCOUC) on the relationship between mortality and extreme temperatures from 1998 to 2008, the Cold Wave in 2008 led to 882 more deaths from natural causes, 19% higher than the normal number of natural deaths recorded in the territory during this season. The number is almost two times more than the tragic death toll of 299 in the 2003 SARS epidemic. The elderly and patients of chronic diseases are in particular vulnerable to the cold wave.
The study further estimated that every 10C drop below 240C in mean temperatures was associated with a 3% increase in natural deaths for the period from 1998-2008, way above the 1% in the Western Europe. This might reflect a lack of preparedness for cold waves in a sub-tropical cities like Hong Kong, in terms of both infrastructures against low temperature as well as people’s awareness.
In addition to the significant adverse impact on the elderly and patients of chronic diseases, prolonged cold spell could also have adverse psychological health outcomes such as depression, as people are confined indoor for prolonged period of time. This psychological health risk seems to have been ignored despite cold weather warnings are issued by the government.
Judging from the sheer magnitude of the adverse health outcomes of cold wave, we believe that the health emergency risks of cold wave deserve a level of awareness and preparedness at least comparable to bird flu, when it seems not to be the case at the moment.
Extreme weather events, including cold wave, heat wave and typhoon, are expected to occur more frequently and severely as a result of global climate change. There is an urgent need to raise the public awareness and preparedness toward these imminent and recurrent natural disasters.
This above information is a follow-up to Prof. Emily Ying Yang Chan’s presentation on “Health Emergency Risks Communication Training in Hong Kong” at Hong Kong Academy of Medicine on 17 February, as part of CCOUC’s effort in drawing the attention of the public to the health emergency risks preparedness in cold spell.
Prof. Emily Ying Yang Chan currently serves as Director of the Collaborating Centre for Oxford University and CUHK for Disaster and Medical Humanitarian Response (CCOUC) (www.ccouc.org), Director of the Centre for Global Health, and Associate Professor of the Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong.
Goggins WB, Chan EYY, Yan C, Chong M. Associations between mortality and meteorological and pollutant variables during the cool season in two Asian cities with sub-tropical climates: Hong Kong and Taipei. Environmental Health. 2013 July: 12:59.
Press coverage in five local newspapers and a local online information platform on healthy life on 21 February 2014 (Chinese Only).