The Covid-19 Antigen Rapid Test Cassette (Oral Fluid) is a rapid chromatographic immunoassay test for the qualitative detection of SARS-CoV-2 nucleocapsid protein antigens in oral fluid samples from individuals with suspected SARS-CoV-2 infection in combination with the clinical presentation and the results of other laboratory tests. The results are for the detection of SARS CoV-2 nucleocapsid protein antigens. During the acute phase of infection, an antigen is usually detectable in upper respiratory tract samples. Positive results indicate the presence of viral antigens, but clinical correlation with patient history and other diagnostic information is required to determine the status of the infection. Positive results do not rule out bacterial infection or coinfection with other viruses. The agent identified may not be the definitive cause of the disease. Negative results do not preclude SARS-CoV-2 infection and should not be used as the sole basis for patient management or treatment decisions. Negative results should be treated as suspected and confirmed with a molecular test if necessary for patient management. Negative results should be considered in the context of the patient’s recent exposures, medical history, and the presence of clinical signs and symptoms consistent with COVID-19. The new coronaviruses belong to the β genus. COVID-19 is an acute respiratory infectious disease. People are generally susceptible to it. Currently, patients infected with the new coronavirus are the main source of infection; even asymptomatic infected people can be an infectious source.Based on the current epidemiological survey, the incubation period is 1-14 days, mostly 3 to 7 days.