Modelling the impact of travel restrictions on COVID-19 cases in Hong Kong in early 2020

Abstract

Background Coronavirus Disease 2019 (COVID-19) led to pandemic that affected almost all countries in the world. Many countries have implemented border restriction as a public health measure to limit local outbreak. However, there is inadequate scientific data to support such a practice, especially in the presence of an established local transmission of the disease. Objective To apply a metapopulation Susceptible-Exposed-Infectious-Recovered (SEIR) model with inspected migration to investigate the effect of border restriction as a public health measure to limit outbreak of coronavirus disease 2019. Methods We apply a modified metapopulation SEIR model with inspected migration with simulating population migration, and incorporating parameters such as efficiency of custom inspection in blocking infected travelers in the model. The population sizes were retrieved from government reports, while the number of COVID-19 patients were retrieved from Hong Kong Department of Health and China Centre for Disease Control (CDC) data. The R0 was obtained from previous clinical studies. Results Complete border closure can help to reduce the cumulative COVID-19 case number and mortality in Hong Kong by 13.99% and 13.98% respectively. To prevent full occupancy of isolation facilities in Hong Kong; effective public health measures to reduce local R0 to below 1.6 was necessary, apart from having complete border closure. Conclusions Early complete travel restriction is effective in reducing cumulative cases and mortality. However, additional anti-COVID-19 measures to reduce local R0 to below 1.6 are necessary to prevent COVID-19 cases from overwhelming hospital isolation facilities.

Outbreak control management: Lessons from SARS‐CoV‐2 infections in 2020–2022 in Hong Kong, an international municipality with high‐frequency travelers

“…Border control management is another critical strategy to prevent disease outbreak. 17 After the announcement of pandemic of COVID‐19, many countries immediately initiated the country lockdown to limit the entry of travelers from high‐risk districts. However, Hong Kong still opens borders to accept influx from all over the world except Hubei Province.…”

Global border restrictions in 2020–2021: Adherence and the effectiveness in long-term COVID-19 epidemic control

“…On the other hand, we found that longer duration of total border closure was significantly associated with higher tourist reduction but remained insignificant in reducing COVID-19 mortality and morbidity. One possible reason is that such extremely stringent measures were usually adopted by countries with rather severe transmissions, and the comprehensive community spreading might be already beyond control even for total lockdown [ 53 ].…”

“…Before and after the COVID-19 pandemic declaration of WHO [ 8 ], restrictions on international travel were adopted with large disparities by global countries [ [9] , [10] , [11] ]. Some of them repatriated tourists from regions with high COVID-19 prevalence and even totally closed the border [ 12 , 13 ], whereas there were other tourism-dependent nations that preferred more moderate measures, including screening (e.g. testing for the reverse transcription polymerase chain reaction (RT-PCR) or antibodies) and quarantining travelers upon their arrival [ 14 , 15 ].…”

International Travel-Related Control Measures to contain The Covid-19 Pandemic: An update to a Cochrane Rapid Review

“…The study does not assess the impact of an air travel-related control measure Hossain 2020 (39) The study does not assess the impact of an air travel-related control measure Hu 2021 (40) The study does not assess the impact of an air travel-related control measure Kamata 2021 (41) The study does not measure the specified interventions Kim 2021 (42) The study does not measure the specified interventions Kong 2021 (43) The study does not provide a specific effect measure for the air travel-related control measure Korzeniewski 2020 (44) The study does not provide a specific effect measure for an air travel-related control measure Kwok 2021 (45) The study does not include air travellers Lai 2021 (46) The study does not measure the specified interventions Liu 2021 (47) The study does not assess the impact of an air travel-related control measure Medby 2021 (48) The study did not incorporate the specified study design Meng 2021 (49) The study does not measure the specified interventions Movsisyan 2021 (50) The study does not provide a specific effect measure for an air travel-related control measure Murall 2021 (51) The study does not include air travellers…”