Molecular Characterization of the Four Serotypes (DENV-1, DENV-2, DENV-3 and DENV-4) of Dengue Virus Circulating in Ouagadougou, Burkina Faso

Abstract

Background and Objectives: Dengue is an arbovirosis caused by the dengue virus with 04 serotypes. The aim of the study was to characterise the four serotypes (DENV-1, DENV-2, DENV-3 and DENV-4) of the dengue virus circulating in Ouagadougou, Burkina Faso. Methods: This was a descriptive analytical study that included 2833 patients and was carried out from January 2021 to December 2022. Rapid diagnosis of dengue was performed using the “Dengue Duo (AgNS1/IgM/IgG)” kit (SD Bioline, Korea). Viral RNA was extracted using the QIAGEN RNA RNeasy Plus Mini Kit (Quiagen, Germany) and virus serotypes were identified using the DENGUE Real-TM Genotype PCR kit (Sacace biotechnologies, Italy). Platelet counts were also performed using the XN-1500 Sysmex. Results: The prevalence of acute infections (NS1Ag positive) by TDR was 5.7% (162/2833), with the peak of dengue virus infection occurring between October and November. On the other hand, the AgNS1+ samples tested by RT-PCR were 53.7% positive for dengue virus; this shows the extent of probable cross-reactions with rapid diagnostic tests and false positives. Serotype 1 accounted for 52.6%, 28.4% had serotype 3, 16.8% had serotype 2 and 2.1% had serotype 4. We found cases of co-infection with DENV-1 and DENV-2 in two patients, co-infection with DENV-1 and DENV-3 in three patients, co-infection with DENV-1 and DENV-4 in one patient, co-infection with DENV-3 and DENV-4 in one patient and co-infection with three serotypes, DENV-1, DENV-2 and DENV-3 in one patient. Conclusion: The study showed that all four serotypes of the dengue virus were circulating in Ouagadougou. Serotype 1 was predominant.