To further investigate the potential of UPT in comparison to standard diagnostic sampling, UPTs of 20 patients with symptoms of ARTI were analyzed in parallel with self-collected nasal swabs in UTM. Sixteen of these patients performed an Ag-RDT on the same day. Results are listed in Table 2. Pathogens that were detected in the nasal swabs were also detected in the corresponding UPT, with the exception of one case where EV/RV was detected only in the nasal swab (Cq 36.6) of a patient who also tested positive for influenza B in both nasal swab (Cq 19.3) and UPT (Cq 26.6) (RP015). The Cq measured in the UPT was usually higher than in the nasal swab, although in some cases it was the other way round (Fig. 1). In all cases where the Ag-RDT tested positive, the corresponding pathogen was also detectable in the UPT. In 4 cases, both the UPT and the nasal swab tested negative with our respiratory panel.
Table 2. Identification of respiratory pathogens in used paper tissues versus nasal swabs and antigen tests (n = 20 samples).