Metagenomic Detection of Two Vientoviruses in a Human Sputum Sample

We used metagenomics to analyze one sputum sample from a patient with symptoms of a respiratory infection that yielded negative results for all pathogens tested. We detected two viral genomes that could be assembled and showed sequence similarity to redondoviruses, a recently described group within the CRESS-DNA viruses. One hundred sputum samples were screened for the presence of these viruses using specific primers. One sample was positive for the same two viruses, and another was positive for one of them. These findings raise questions about a possible role of redondoviruses in respiratory infections in humans.