High Rate of anti-SARS-CoV-2 Antibodies along the River Corridor during the COVID-19 Epidemic in the Republic of Congo, 2022

Author(s): Eyenet Boussam Dachel Aymard, Dossou-Yovo Louis Régis, Koukouikila koussounda Felix, Kankou Jean Médard, Pembé Issamou Mayengué, Niama Roch Fabien

Objectives: Few studies are available on the circulation of SARS-CoV-2 in rural areas, particularly in areas difficult to access during the epidemic in Africa. The aim of the present study was to determine the carriage rate of anti-SARS-CoV-2 antibodies in unvaccinated people living along the river corridor in the Republic of Congo, between July and August 2022.

Methods: DBS were used as sampling method taken and analyzes using the microsphere assay technique with beads coupled to an antibody directed for the search for antibodies against the Sprike protein of SARS-CoV-2.

Results: Of 168 samples analyzed, 143 (85%) were positive, 3 (2%) negative and 22 (13%) equivocal. This seroprevalence varied according to locality, but was not significant (p=0.13). Indeed, the lowest prevalence was observed in Bouemba (75%), while Liranga with 93% had the highest rate.

Conclusion: Despite the relative weakness of data on the circulation of SARS-CoV-2 in remote and landlocked areas, this study demonstrates the intensive circulation of this virus during the epidemic peak even in difficult-to-access regions like that of our study.