RESUMO
Since March 2020, the Kingdom of Saudi Arabia (KSA) has launched several digital applications to support the intervention response to reduce the spread of SARS-CoV-2. At the beginning of 2021, the KSA Government introduced a mandatory immunity passport to regulate access to public venues. The passport was part of the strategy of resuming public activities before reaching high vaccination coverage. The passport was implemented as a new service in the Tawakkalna mobile phone application (App). The immunity passport allowed access to public locations only for the users who recovered from COVID-19 or those who were double vaccinated. Our study aimed to evaluate the effectiveness of the immunity passport, implemented through the Tawakkalna App, on SARS-CoV-2 spread. We built a spatial-explicit individual-based model to represent the whole KSA population (IBM-KSA) and its dynamic on a national scale. The IBM-KSA was parameterized using country demographic, remote sensing, and epidemiological data. The model included non-pharmaceutical interventions and vaccination coverage. A social network was created to represent contact heterogeneity and interaction among age groups of the population. The IBM-KSA also simulated the movement of people across the country based on a gravity model. We used the IBM-KSA to evaluate the effect of the immunity passport on the COVID-19 epidemics outcomes. The IBM-KSA results showed that implementing the immunity passport through the Tawakkalna App mitigated the SARS-CoV2 spread. In a scenario without the immunity passport, the KSA could have reported 1,515,468 (95% confidence interval [CI]: 965,725-1,986,966) cases, and 30,309 (95% CI: 19,314-39,739) deaths from March 2021 to November 2021. The comparison of IBM-KSA results with COVID-19 official reporting estimated that the passport effectively reduced the number of cases, hospitalizations, and deaths by 8.7 times, 13.5 times, and 11.9 times, respectively. These results showed that the introduction of the immunity passport through the Tawakkalna App was able to control the spread of the SARS-COV-2 until vaccination reached high coverage. By introducing the immunity passport, The KSA was able to allow to resume most of public activities safely.
