Detection of SARS-CoV-2 among travellers entering Ghana through the Kotoka International Airport at the peak of the COVID-19 pandemic: 2021 to 2022

Background: The emergence of COVID-19 disrupted health systems and programs, and the impact of its spread and consequences led to the shutdown of country borders worldwide. As part of the Ghanaian government’s measures to hasten the opening of its borders, a surveillance system was instituted at the Kotoka International Airport (KIA) to detect and monitor SARS-CoV-2 variants imported into the country. Objective: This study aimed to screen international travellers arriving in Ghana for SARS-CoV-2, characterise imported viral variants, and assess the role of rapid antigen testing and mandatory isolation in preventing community transmission. Methods: All arriving passengers at the KIA, except for children under five (5), were required to undergo mandatory antigen testing. The data presented in this study were from 2021 to 2022. Reactive travellers to SARS-CoV-2 antigen testing were placed under compulsory isolation, and retesting was conducted using real-time polymerase chain reaction (RT-PCR). The detected viruses were further sequenced using Oxford Nanopore technologies to identify variants. Results: Of the travellers arriving at the KIA, 3331 were SARS-CoV-2 Ag+, and 73.73% (n = 2456/3331) were confirmed positive by RT-PCR. The mean age was 37 years, with most cases detected between the ages of 21 and 50. Travellers from Nigeria, Italy, and France had the highest reactive cases upon arrival. All the WHO-labelled variants, including the recombinant variant, were detected upon characterisation. Vaccination among reactive travellers was approximately 32% (n = 1065/3331). Conclusion: This study highlights the importance of establishing health surveillance systems at points of entry: these effectively monitor disease importation and transmission. Also, this study reiterates the vital role rapid antigen testing plays in the event of a public health crisis.