Diagnostics and spread of SARS-CoV-2 in Western Africa: An observational laboratory-based study from Benin | medRxiv preprints (not peer reviewed)

Type Journal Article Author Anges Yadouleton Author Anna-Lena Sander Author Andres Moreira-Soto Author Carine Tchibozo Author Gildas Hounkanrin Author Yvette Badou Author Carlo Fischer Author Nina Krause Author Petas Akogbeto Author Edmilson F. de Oliveira Filho Author Anges Dossou Author Sebastian Bruenink Author Melchior AIssi Author Mamoudou Harouna Djingarey Author Benjamin Hounkpatin Author Michael Nagel Author Jan felix Drexler URL https://www.medrxiv.org/content/10.1101/2020.06.29.20140749v1 Rights © 2020, Posted by Cold Spring Harbor Laboratory. The copyright holder for this pre-print is the author. All rights reserved. The material may not be redistributed, re-used or adapted without the author's permission. Pages 2020.06.29.20140749 Publication medRxiv Date 08/07/2020 Extra Publisher: Cold Spring Harbor Laboratory Press DOI 10.1101/2020.06.29.20140749 Accessed 2020-09-23 10:47:17 Library Catalog www.medrxiv.org Language en Abstract Information on severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spread in Africa is limited by fragile 2 surveillance systems and insufficient diagnostic capacity. 3 We assessed the coronavirus disease-19 (COVID-19)-related diagnostic workload in Benin, Western Africa, 4 characterized SARS-CoV-2 genomes from 12 acute cases of COVID-19, used those together with public data to 5 estimate SARS-CoV-2 transmission dynamics in a Bayesian framework, validated a widely used diagnostic dual target 6 RT-PCR kit donated to African countries, and conducted serological analyses in 68 sera from confirmed COVID-19 7 cases and from febrile patients sampled before the predicted SARS-CoV-2 introduction. 8 We found a 15-fold increase in the monthly laboratory workload due to COVID-19. Genomic surveillance showed 9 introductions of three distinct SARS-CoV-2 lineages. SARS-CoV-2 genome-based analyses yielded an R0 estimate of 10 4.4 (95% confidence interval: 2.0-7.7), suggesting intense spread of SARS-CoV-2 in Africa. RT-PCR-based tests 11 were highly sensitive but showed variation of internal controls and between diagnostic targets. Commercially available 12 SARS-CoV-2 ELISAs showed up to 25% false-positive results depending on antigen and antibody types, likely due 13 to unspecific antibody responses elicited by acute malaria according to lack of SARS-CoV-2-specific neutralizing 14 antibody responses and relatively higher parasitemia in those sera. 15 We confirm an overload of the diagnostic capacity in Benin and provide baseline information on the usability of 16 genome-based surveillance in resource-limited settings. Sero-epidemiological studies needed to assess SARS-CoV-2 17 spread may be put at stake by low specificity of tests in tropical settings globally. The increasing diagnostic challenges 18 demand continuous support of national and supranational African stakeholders. Short Title Diagnostics and spread of SARS-CoV-2 in Western Africa