Between 2020 and 2025, the COVID-19 outbreaks have caused a cumulative total of over 0.7 billion cases, with over 7 million deaths. After the end of COVID-19 pandemic, the pattern of respiratory infections has changed substantially and there are significant geographical and temporal variations. Different from the pre-COVID-19 era, the epidemiologic patterns and seasonality of respiratory infections today is far from clear, as various respiratory pathogens had re-emerged in the lack of population immunity during the COVID-19 years. Public health surveillance plays a crucial role in the development of strategies for the prevention and control of respiratory epidemics. Defined as the ongoing systematic collection, analysis, interpretation and timely dissemination of relevant data, public health surveillance is normally laboratory or health services-based. In recent years, the growth of digital technologies has enabled the implementation of surveillance that effectively captures respiratory syndrome signals, notably influenza-like illnesses (ILI) in the community. With the wider availability of rapid testing for different pathogens, the diagnostic markers in the population can also be collected timely by relevant stakeholders. Against these backgrounds, “EcSS+” was established in 2025 and positioned as a community-based surveillance platform in Hong Kong.
