Malaria in Hong Kong: Impact, eradication and legacy

Abstract

Background: This presentation explores how the impact of malaria and the process of its eradication shaped the development of Hong Kong, its scientific and medical expertise and legacy for preparedness. Methods & Materials: Primary sources - surviving colonial medical records, journals, diaries, newspapers and government reports were analysed for quantitative and qualitative information. Secondary sources - peer-reviewed journal articles, books and online sources (webpages, libraries, search engines). Results: Malaria had a major impact on the development of Hong Kong. High disease mortality in the early years of the colony influenced where and how people lived, as well as driving local medical expertise. Initially, the cause was attributed to Hong Kong's insalubrious environment and miasmatic presumptions dominated Western and Chinese medical thinking. In the absence of scientific delineation, fever-inducing diseases including malaria were typically grouped together, which led to a local catchall moniker ‘Hong Kong Fever’. Discoveries of the etiology and transmission of malaria proved key to the development of effective control methods and as Hong Kong grew, targeted public health measures became increasingly important. The colonial government's determination to build a viable long-term colony in a widely malarious region necessitated local problem solving. The establishment of a dedicated ‘Malaria Bureau’ in 1930 provided the targeted approach necessary to provide a holistic solution to the problem. A number of challenges threatened progress against the disease, including waves of migrants from neighbouring malarious countries (in particular mainland China) and the disruption of the Second World War. Eradication of indigenous cases was eventually realized in 1969, nearly 130 years after Hong Kong was colonised. Periodic outbreaks continued to occur as late as the 1980's fuelled by residential development of the New Territories, the influx of Vietnamese refugees and imported immigrant and tourist cases, threatening a reintroduction of malaria in local mosquito populations. Conclusion: The eradication of malaria in Hong Kong was a gradual process dependent on scientific knowledge, medical expertise, colonial government policy, public education and vigilance. As an emerging disease ‘hotspot’, these factors are particularly relevant in twenty-first century Hong Kong and remain inherent features of local infectious disease preparedness planning.