COVID-19 may become a seasonal disease. SARS-CoV-2 active circulation coupled with vaccination efforts has undoubtedly modified the virus dynamic. It is therefore important investigate SARS-CoV-2 dynamic in different groups of population following the course of spatiotemporal variance and immunization. To investigate SARS-CoV-2 clearance in different ethnic groups and the impact of immunization, we recruited 777 SARS-CoV-2-positive patients (570 Africans, 156 Caucasians, and 51 Asians). Participants were followed and regularly tested for 2 months until they had two negative tests. The vaccination rate was 64.6%. African individuals were less symptomatic (2%), Caucasians (41%) and Asians (36.6%). On average, viral clearance occurred after 10.5days. Viral load at diagnosis was inversely correlated with viral clearance (p < 0.0001). The time of SARS-CoV-2 clearance was higher in Africans and Caucasians than in Asians (Dunn's test p < 0.0001 and p < 0.05, respectively). On average, viral clearance occurred within 9.5days during the second semester (higher rate of vaccination and SARS-CoV-2 exposition), whereas it took 13.6days during the first semester (lower rate of vaccination and SARS-CoV-2 exposition) (Mann-Whitney t-test p < 0.0001). In conclusion, ethnicity and spatiotemporal changes including SARS-CoV-2 exposition and immunization affect SARS-CoV-2 clearance.
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