Disclosed are compositions, assays, methods, diagnostic methods, kits and diagnostic kits for the specific and differential detection of SARS-CoV-2, including SARS-CoV-2 variants, or other coronaviruses from samples including veterinary samples, clinical samples, food samples, forensic sample, an environmental sample (e.g., soil, dirt, garbage, sewage, air, or water), including food processing and manufacturing surfaces, or a biological sample.