JMIR Publications

ABSTRACT

Background:

Following the COVID-19 pandemic, returning to normalcy has become the primary goal of global cities. The key for returning to normalcy is to minimize the impact on socioeconomic activities while ensuring that the epidemic is under control. On this account, it is essential to control the pandemic in a precise manner to reduce the socioeconomic cost. However, there are limited developments in models for estimating the spatiotemporal epidemic spread at the refined scale within the city to support precise epidemic. For most of 2021, Hong Kong has remained at the top of the "global normalcy index" because of its effective responses. The urban-community-scale spatiotemporal onset risk prediction model of COVID-19 symptom has been used to assist in the precise epidemic control of Hong Kong.

Objective:

This study aims to develop a solution to assist in precise prevention and control for returning to normalcy, by using the spatiotemporal prediction models of COVID-19 symptom onset risk and its over one year of application experience in Hong Kong.

Methods:

Based on a spatiotemporal solution proposed in 2021 and applied to support the epidemic control in Hong Kong, an enhanced urban-community-scale geographic model is further proposed to predict the risk of COVID-19 symptom onset by quantifying the impact of transmissibility of SARS-CoV-2 variants, vaccination, and the imported case risk. The prediction results could be applied to make short-term onset risk predictions at the urban community scale, identify high-onset-risk communities, estimate the effectiveness of intervention measures implemented, and designing further response measures through simulation. The applications can be automized by being integrated into an online platform.

Results:

Daily predicted onset risk in 291 TPUs of Hong Kong from 18 January 2020 to 22 April 2021 was obtained from the enhanced prediction model. The prediction accuracy in the following 7 days was over 80%. The prediction results were used to effectively assist the epidemic control of Hong Kong in the following application examples: i) identified communities within high-onset-risk always only accounted for 2%-25% in multiple epidemiological scenarios; ii) effective COVID-19 response measures such as prohibiting public gathering of more than four people were found to reduce the onset risk by 16% to 46%; iii) through the effect simulation of new compulsory testing measure, the onset risk was found to be reduced by more than 80% in 14.43% of the TPUs, and by more than 60% in 32.99% of the TPUs.

Conclusions:

The proposed solution can support sustainable and targeted pandemic responses for returning to normalcy. Faced with the situation that may coexist with SARS-CoV-2, this study can not only assist global cities in responding to the future epidemic effectively, but also help to restore the social-economic activities and people's normal lives.