For the diagnosis of SARS-CoV-2 (Covid19), serum, lower respiratory tract samples (bronchoalveolarlavage, sputum, tracheal aspirate) and upper respiratory tract samples (nasopharyngeal fluids and swab) taken from individuals meeting clinical criteria, or either is a diagnostic kit that works on the basis of reproducing target nucleic acids using RNA isolated from samples taken from individuals seeking diagnosis for different purposes.