Epidemiological characterisation of asymptomatic carriers of COVID-19 in Colombia: a cross-sectional study

Teherán, Aníbal A.; Camero Ramos, Gabriel; Prado de la Guardia, Ronald; Hernández, Carolina; Herrera, Giovanny; Pombo, Luis M; Avila, Albert Alejandro; Flórez, Carolina; Barros, Esther C; Perez-Garcia, Luis; Paniz-Mondolfi, Alberto; Ramírez, Juan David

INTRODUCTION: Asymptomatic carriers (AC) of the new SARS-CoV-2 represent an important source of spread for COVID-19. Early diagnosis of these cases is a powerful tool to control the pandemic. Our objective was to characterise patients with AC status and identify associated sociodemographic factors. METHODS: Using a cross-sectional design and the national database of daily occurrence of COVID-19, we characterised both socially and demographically all ACs. Additional correspondence analysis and logistic regression model were performed to identify characteristics associated with AC state (OR, 95% CI). RESULTS: 76.162 ACs (12.1%; 95% CI 12.0% to 12.2%) were identified, mainly before epidemiological week 35. Age≤26 years (1.18; 1.09 to 1.28), male sex (1.51; 1.40 to 1.62), cases imported from Venezuela, Argentina, Brazil, Germany, Puerto Rico, Spain, USA or Mexico (12.6; 3.03 to 52.5) and autochthonous cases (22.6; 5.62 to 91.4) increased the risk of identifying ACs. We also identified groups of departments with moderate (1.23; 1.13 to 1.34) and strong (19.8; 18.6 to 21.0) association with ACs. CONCLUSION: Sociodemographic characteristics strongly associated with AC were identified, which may explain its epidemiological relevance and usefulness to optimise mass screening strategies and prevent person-to-person transmission.