A lateral-flow immunochromatographic assay for the detection of nucleocapsid protein antigens specific to SARS-CoV-2. Uses anterior nasal swab specimens self collected by individiuals 15 or older or collected by an adult from an individual aged two years or older. This test is authorized for individuals with symptoms of COVID-19 within the first seven days of symptom onset when tested at least twice over three days with at least 48 hours between tests, and for indivudals without symptoms or other epidemiological reasons to suspect COVID-19, when tested three times over five days with at least 48 hours between tests.