The respiratory virome and exacerbations in patients with chronic obstructive pulmonary disease

van Rijn, Anneloes L.; van Boheemen, Sander; Sidorov, Igor; Carbo, Ellen C.; Pappas, Nikos; Mei, Hailiang; Feltkamp, Mariet; Aanerud, Marianne; Bakke, Per; Claas, Eric C. J.; Eagan, Tomas M.; Hiemstra, Pieter S.; Kroes, Aloys C. M.; de Vries, Jutte J. C.

Furthermore, the complete respiratory virome showed a high bacteriophage abundance that could be linked to the absence of viral pathogens. Lower bacteriophage abundance may be the result of viral expansion. Hypothetically, a healthy virome size and diversity fits a certain size and diversity of bacteriophages, while during viral infection, pathogens predominate the virome. Alternatively, others have hypothesized that viral and microbial diversity may play a role in infection susceptibility and the development of acute and chronic respiratory diseases [33] . Our results indicate that virome dysbiosis may be accompanied by bacteriome dysbiosis, though no significant differences were detected in line with other reports [40, 41] . However, these studies don't compare between COPD exacerbation with and without viral infections. Others have found a higher phage abundance in a patient with severe COPD when compared with one patients with moderate COPD and healthy controls, DNA sequencing, in line with the hypothesis of a state of dysbiosis that increases with disease progression [27] . In COPD patients, viral infections have been suggested to trigger bacterial overgrowth and infections [42, 43] , demonstrating the significance of viral-bacterial interactions. Moreover, hypothetically, bacteriophages play a role in the horizontal gene transfer of bacterial virulence factors.