Impact of ACE2 and TMPRSS2 Activity on Clinical Manifestations of COVID-19 in Pointe-Noire, Congo

Introduction: The COVID-19 pandemic caused by SARS-CoV-2 exhibits marked clinical heterogeneity, ranging from asymptomatic cases to severe complications. Viral entry depends on ACE2 and TMPRSS2 proteins, whose activity may influence disease progression. Objective: To evaluate the association between ACE2 and TMPRSS2 activity and the severity of COVID-19 clinical manifestations. Methods: A cross-sectional descriptive study included 170 RT-PCR confirmed SARS-CoV-2 patients. Demographic (age, sex) and clinical (symptom) data were extracted from medical records. ACE2 and TMPRSS2 protein activity was measured using immunoenzymatic assays from blood samples. Patients were stratified into moderate and severe forms according to standardized clinical criteria. Results: The average age was 31.7 ± 4.4 years (range 24–68), with a male predominance (78%). Predominant symptoms in severe forms included fever (54.6%), cough (55.6%), and ageusia (56%). A significant correlation was found between ACE2 activity and severe disease forms (p < 0.001). TMPRSS2 activity was also associated with severity, though less prominently (p = 0.029). Conclusion: These findings suggest that ACE2 and TMPRSS2 activity may serve as predictive biomarkers of COVID-19 severity. Quantifying these markers could enable early patient stratification and optimized therapeutic strategies. Prospective studies are needed to validate their clinical utility.