Abstract: The present invention is concerned with the detection of a SARS-Cov-2 vims antigen including, for example, a SARS-Cov-2 virus nucleocapsid protein and/or a SARS-Cov-2 virus spike protein. The present invention provides novel polynucleotide sequences which spontaneously fold to form aptamers having secondary structure features that promote selective binding to a SARS-CoV-2 virus antigen. The present invention further provides test kits and assay methods which employ the polynucleotides described herein, to achieve a more accurate, lower cost, rapid diagnosis COVID-19 test intended to accelerate contact tracing and testing of individuals and the community in the management of the ongoing global pandemic caused by various strains of SARS-CoV-2 virus.