Seroreactivity to SARS-CoV-2 during Pre-Pandemic and Pandemic Periods of Covid-19 of Populations Living in a Malaria Endemic Area in Burkina Faso

Malaria-endemic countries in Africa have recorded the lowest number of covid-19 cases and deaths compared to other countries. Pre-existing Naturally acquired Immunity to malaria was an hypothesis that was stated to explain this situation. In a context where malaria is endemic, we carried out this study in order to investigate the existence of antibody cross-reactivity between COVID-19 and malaria and to estimate the seroprevalence of COVID-19 during the third year of the pandemic in the plateau central Region in Burkina Faso. Samples collected in 2007 and positive for IgG against Plasmodium falciparum alpha-helical coiled coil proteins were used to look for a possible antibody cross-reactivity with SARS-CoV-2 antigens. Samples collected in 2022 were used to estimate the seroprevalence of COVID-19. A total of 628 individuals of both sexes, aged over 5 years were enrolled. The seroprevalence of anti-SARS-CoV-2 antibodies was measured using an ELISA test and an RDT. All the samples collected in 2007 showed no cross-reactivity between SARS-CoV-2 and Plasmodium falciparum. The seroprevalence during the third year of the pandemic was 100% and 86.88% respectively by ELISA and RDT. The proportions of IgG and IgM antibodies were respectively 86.56% and 2.81%. The results did not show antibody cross-reactivity between SARS-CoV2 and Plasmodium falciparum in the study population. High exposure to SARS-CoV-2 was found in the study area in 2022. Due to their high specificity, WANTAI ELISA and Right Sign RDT can be considered as good serological tools for COVID-19 serosurveillance in a context where malaria is endemic.