<b>Background and Objective:</b> Dengue is a remerging vector-borne viral disease in Burkina Faso since the outbreak of 2013 and requires special attention from health authorities. This study reports the prevalence of dengue fever serological markers (NS1Ag, IgM and IgG) and infection dynamic from January, 2018 to December, 2020 among patients tested for dengue infection at Saint Camille Hospital of Ouagadougou (HOSCO). <b>Materials and Methods:</b> The study population consisted of 6414 patients aged 0-97 years. Dengue virus infection was detected in serum or plasma using the SD bioline dengue duo rapid detection kit. <b>Results:</b> The prevalence of dengue NS1Ag was 2.25% (45/2003), 18.43% (501/2719) and 2.42% (38/1569) in the study population in 2018, 2019 and 2020, respectively. The age groups over 50 years and 15-20 years were significantly more infected compared to the group 21-30 years respectively in 2019 (p = 0.030) and 2020 (p = 0.035). Patients tested positive for at least one of these markers (NSlAg, IgG and IgM) represented 26.01% (521/2003) and 38.98% (1060/2719). The peak of infection during 2018 and 2019 was observed between October and November. The present study reports a high seroprevalence of acute dengue virus infection. The presence of NS1Ag, IgM and IgG in patients suggests an active circulation of the dengue virus in Ouagadougou. <b>Conclusion:</b> Data shows recurrent outbreaks of dengue infection in our country need strong surveillance and a suitable and affordable diagnostic system to clarify the burden, pinpoint the risk factors and for better case management.
Keywords: Burkina Faso; Dengue; IgG; IgM; NS1Ag; seroprevalence.