Economic Analysis of Border Control Policies during COVID-19 Pandemic: A Modelling Study to Inform Cross-Border Travel Policy between Singapore and Thailand

Abstract

With countries progressing towards high COVID-19 vaccination rates, strategies for border reopening are required. This study focuses on Thailand and Singapore, two countries that share significant tourism visitation, to illustrate a framework for optimizing COVID-19 testing and quarantine policies for bilateral travel with a focus on economic recovery. The timeframe is the month of October 2021, when Thailand and Singapore were preparing to reopen borders for bilateral travel. This study was conducted to provide evidence for the border reopening policy decisions. Incremental net benefit (INB) compared to the pre-opening period was quantified through a willingness-to-travel model, a micro-simulation COVID-19 transmission model and an economic model accounting for medical and non-medical costs/benefits. Multiple testing and quarantine policies were examined, and Pareto optimal (PO) policies and the most influential components were identified. The highest possible INB for Thailand is US $125.94 million, under a PO policy with no quarantine but with antigen rapid tests (ARTs) pre-departure and upon arrival to enter both countries. The highest possible INB for Singapore is US $29.78 million, under another PO policy with no quarantine on both sides, no testing to enter Thailand, and ARTs pre-departure and upon arrival to enter Singapore. Tourism receipts and costs/profits of testing and quarantine have greater economic impacts than that from COVID-19 transmission. Provided healthcare systems have sufficient capacity, great economic benefits can be gained for both countries by relaxing border control measures.

Keywords: COVID-19; border-opening policy; economic evaluation; transmission; willingness to travel.

Figure 1

Whole model diagram. Abbreviations: COVID-19, coronavirus disease 2019; SG, Singapore; TH, Thailand; NMB, net monetary benefit; INB, incremental net benefit. The whole model diagram illustrates how sub-models work together to identify the Pareto optimal bilateral policies of testing and quarantine.

Figure 2

Transmission diagram of a round trip from Country A to Country B. The left diagram illustrates the possible itineraries of the cohort infected in Country A (home country) before they start the trip. The right diagram illustrates the possible itineraries of the cohort infected in Country B (destination country).

Figure 3

Incremental net benefit of Singapore and Thailand under all bilateral policy options, with Pareto optimal policies and worst policies highlighted. Abbreviations: SG, Singapore; TH, Thailand; INB, incremental net benefit; PO, Pareto optimal; m, million. Horizon: 1 month. Unit of INB for horizontal and vertical axes: million USD. Each hollow dot represents one bilateral policy option. The horizontal coordinate is the INB of TH and the vertical coordinate is the INB of SG. Three PO policy pairs are highlighted as triangle dots: (i) Both TH and SG do not require quarantine but require ARTs pre-departure and upon arrival to enter both TH and SG (S4), with INB of TH at US $125.94 m and SG at US $27.36 m; (ii) TH requires no quarantine and no testing (S9), whilst SG requires no quarantine but requires ARTs pre-departure and upon arrival to enter SG (S4), with INB of TH at US $123.97 m and SG at US $29.78 m; (iii) SG requires no quarantine and no testing (S9), whilst TH requires no quarantine but requires ARTs pre-departure and upon arrival to enter SG (S4), with INB of TH at US $125.14m and SG at US $27.78 m. Worst policy pairs are highlighted as square dots. Worst for TH: TH requires 14-day quarantine but no testing (S9), whilst SG requires 14-day quarantine, PCR pre-departure, upon arrival, and quarantine exit tests, with daily ART during quarantine (S5), giving TH an INB of −US $0.02m and SG US $0.02m. Worst for SG: TH requires 5-day quarantine, PCR pre-departure, upon arrival, and quarantine exit tests, with daily ART during quarantine (S5), whilst SG requires no quarantine but requires ARTs pre-departure and upon arrival (S4), giving TH an INB of US $55.31 m and SG −US $10.36 m. Worst for TH and SG combined (total INB): Both TH and SG require 14-day quarantine, PCR pre-departure, upon arrival, and quarantine exit tests, with daily ART during quarantine (S5), resulting in a total INB of −US $0.03 m, with INB of TH at US $0.03 m and of SG at −US $0.06 m.

Figure 4

Influential components of incremental net benefit. Abbreviations: COVID-19, coronavirus disease 2019; SG, Singapore; TH, Thailand; INB, incremental net benefit; TTI, test-trace-isolation. Ten components with the largest range for TH are sorted in (A); ten components with the largest range for SG are sorted in (B). A larger range indicates a more influential cost/benefit component to the country’s INB. The numbering in front of each cost/benefit component corresponds to that in Table 2.