Wuhan, Hubei Province, China – in December 2019 the first cases of unknown pneumonia were recorded (1). It was the beginning of the war in which we are now taking part. We fight against an invisible enemy – virus called SARS-CoV-2. Droplet route of infection, greater contagiousness compared to the SARS or MERS virus (2, 3) and induction of acute respiratory distress syndrome (ARDS) causes that we must have methods that allow us to detect and eliminate it.

We can take samples from upper airway (pharyngeal and nasal swabs), lower airway (sputum, airway secretions, bronchoalveolar lavage fluid), blood, feces, urine and conjunctival secretions. The material of choice should be sample from the lower respiratory tract because of the highest content of viral nucleic acids (after 3-5 days from the onset of symptoms is the peak of secretion), which allows to avoid false negative results (4).