Análise do efeito da sintomatologia e da carga viral na detecção correcta de casos positivos de SARS-CoV-2 pelos testes rápidos de antı́genos (Panbio e STANDARD Q) em Maputo

Abstract

COVID-19, declared a pandemic by the World Health Organization (WHO) in 2020, rein- forced the need for rapid methods for diagnosing SARS-CoV-2. Although Rapid Antigen Tests (Ag-TDRs) are widely used, their low sensitivity may compromise the detection of positive cases of the virus. The objective of this study was to evaluate the effect of symptomatology and viral load on the correct detection of positive SARS-CoV-2 cases by the Panbio and STANDARD Q Ag-TDRs in Maputo. The methodology included concordance analysis using Cohen’s Kappa coefficient, determination of sensitivity and specificity, and multiple logistic regression. The results indicated high specificity (>97%) for both tests and low sensitivity (58% for Panbio and 45% for Q STANDARD), confir- ming the limitations of the tests in identifying positive cases. Symptomatic individuals, those with less than seven days of symptoms, and those with higher viral loads were more likely to obtain a correct positive result.