© Hong Kong Academy of Medicine. CC BY-NC-ND 4.0
Low mortality and severe complications despite high influenza burden among Hong Kong children
KL Hon, MB, BS, MD1,2; Julian W Tang, PhD, FRCPath3
1 Department of Paediatrics and Adolescent Medicine, The Hong Kong Children’s Hospital, Kowloon Bay, Hong Kong
2 Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
3 Department of Infection, Immunity and Inflammation, University Hospitals of Leicester NHS Trust, United Kingdom
Corresponding author: Dr KL Hon (ehon@hotmail.com)
 Full paper in PDF
To the Editor—Every winter, the Hong Kong Hospital Authority appeals to the public for understanding amid overcrowding at the city’s public hospitals as influenza cases spike. The Centre for Health Protection (CHP) has been reporting the annual influenza burden and confirms that, in Hong Kong, there has been no significant increase in mortality among patients with influenza aged <18 years. Among paediatric patients, there are few severe cases and few deaths each year, usually among unimmunised children, in a population of around 1.5 million children and youths.1 2 3 4 5
The burden on public hospitals may be due, in part, to the low immunisation rate among children. Paediatric patients with severe influenza may require in-patient stays of 1 to 2 days. Paediatric patients who require urgent care must be prioritised and should not have to wait for >8 hours pending assessment or admission. Yet this may be inevitable if the department becomes overcrowded with too many competing demands on staff time. Ideally, patients should be seen initially by their family doctors and stay home to recover if their admission is not necessary or urgent.
Excessive and exaggerated media publicity over the relatively few annual influenza-related deaths and severe cases may contribute to public panic, with increased admissions, some of which may be unnecessary, leading to higher workloads for medical staff—all of which may serve to delay the assessment of severe cases. The media may constructively spend their energy in lobbying for immunisation in the local healthcare system to help to relieve the pressure on an already over-burdened and under-funded hospital healthcare system.
Seasonal influenza continues to cause significant morbidity, but not mortality or intensive care admissions among children and young persons in Hong Kong. Influenza-related morbidity in terms of severe cases in patients aged <18 years has increased but the total number is still low Table 6).

Table. Cases, severe cases and mortality due to seasonal influenza in Hong Kong6
Immunisation rates can be enhanced using targeted strategies for healthcare practices and providers. Sufficient vaccine supply should be secured annually. School vaccination teams provide excellent timely delivery of vaccines to schoolchildren. Private medical practitioners are also generally willing to be involved and their involvement would help to relieve the intense manpower needed for influenza vaccination prior to (and sometimes during) the annual influenza season.
Influenza is a serious public health concern globally. Public misunderstandings, unfounded fears, and various myths surrounding influenza, influenza vaccines, and other essential childhood immunisations must be addressed. Prevention and prompt diagnosis and treatment of influenza reduces morbidity.7 Physicians, school teachers, parents, and policy makers should cooperate to effectively coordinate and deliver the annual seasonal influenza immunisation programme, as well as the management of acute influenza infections that present to our healthcare services. Children with infectious diseases who are nevertheless still relatively well should try to recover at home and avoid school, nurseries, or other public places, to prevent the spread of infectious diseases such as influenza.
Author contributions
All authors have contributed to the concept, acquisition of data, analysis of data, drafting of the article, and critical revision for important intellectual content. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.
Conflicts of interest
All authors declared no conflicts of interest.
This report received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
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