Background: Olfactory dysfunction (OD) is a common manifestation of SARS- CoV-2 infection but remains insufficiently documented in sub-Saharan Africa, particularly among highly exposed healthcare workers. Objective: To estimate the prevalence of OD during RT-PCR-confirmed COVID-19, describe its clinical characteristics, and identify associated factors among hospital staff in N’Djamena. Methods: An analytical cross-sectional study was conducted between January and June 2023 among hospital workers with RT-PCR-confirmed SARS-CoV-2 infection, interviewed at least four weeks after the acute episode. A standardized questionnaire documented OD occurring during infection, including type, onset characteristics, nasal obstruction, associated dysgeusia, duration, and recovery. A simplified psychophysical olfactory test using five locally familiar odorants was proposed to participants reporting persistent symptoms or uncertainty regarding recovery. Factors associated with OD were assessed using multivariable logistic regression analysis. Results: Among 161 participants, 115 reported OD (71.4%). Anosmia was the predominant presentation (91.3%), typically of sudden onset (85.2%) and most often without nasal obstruction (87.8%). Assignment to clinical departments was strongly associated with OD (adjusted OR 12.4; 95% CI 5.2 - 29.8), whereas age was inversely associated (adjusted OR 0.94 per year increase). Complete recovery was reported by 90.4% of affected participants; 5.2% had persistent, objectively confirmed OD (score ≤ 2/5). Additionally, 50.4% reported difficulty detecting potentially hazardous odors. Conclusion: Olfactory dysfunction related to SARS-CoV-2 remains highly prevalent among healthcare workers in N’Djamena, particularly among those assigned to clinical services, and is associated with a measurable functional impact on workplace safety. These findings support systematic post-COVID evaluation and targeted preventive strategies in this high-risk professional group.
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