Abstract
Host-microbiota interactions are important in shaping immune responses that have the potential to influence the outcome of pathogen infection. However, most studies have focused on the gut microbiota and its possible association with disease outcome, while the role of the nasal microbiota and respiratory pathogen infection has been less well studied. Here we examined changes in the composition of the nasal microbiota of pigs following experimental infection with porcine reproductive and respiratory syndrome virus 2 (PRRSV-2), swine influenza A H3N2 virus (H3N2) or both viruses. DNA extracted from nasal swabs were subjected to 16S rRNA sequencing to study the composition of the nasal microbiota. Bacterial richness fluctuated in all groups, with a slight reduction in pigs singly infected with PRRSV-2 and H3N2 during the first 5 days of infection compared to uninfected controls. In contrast, nasal bacterial richness remained relatively stable after PRRSV-2/H3N2 co-infection. PRRSV-2 and H3N2, alone or in combination differentially altered the abundance and distribution of bacterial families. Single and co-infection with PRRSV-2 or H3N2 was associated with the expansion of the Neisseriaceae family. A positive correlation between H3N2 viral load and the relative abundance of the Neisseriaceae was observed. However, further mechanistic studies are required to understand the significance of the changes in specific bacterial families following these viral infections.
Highlights
In the last 10 years extensive studies undertaken in humans and farm animals have indicated the important role that microbiota diversity and composition plays in the control of infectious diseases
To evaluate how the nasal microbiota was affected after experimental infection of pigs with porcine reproductive and respiratory syndrome virus 2 (PRRSV-2), H3N2, or simultaneously with both viruses porcine reproductive and respiratory syndrome virus (PRRSV)-2/H3N2, nasal swab samples collected −12, 0, 1, 2, 3, 4 and 5 days post-infection were analyzed by next-generation sequencing of the V4–V5 region of 16S rRNA
On average 12 days before the challenge (−12 dpi), the uninfected, PRRSV-2, H3N2 and PRRSV-2/H3N2 co-infected groups presented with a mean of 96, 185, 265 and 86 operational taxonomic units (OTUs), Pathogens 2021, 10, x FOR PEER REVIEW
Summary
In the last 10 years extensive studies undertaken in humans and farm animals have indicated the important role that microbiota diversity and composition plays in the control of infectious diseases. Numerous studies have shown the importance of the gut microbiota on immunity to respiratory infections, there is little knowledge as to how these two complex systems interact [1]. Antibiotic induced dysbiosis of the intestinal microbiota in mice resulted in impaired immune responses, leading to increased influenza A virus (IAV) [2,3] or Mycobacterium tuberculosis [4] burdens in the lungs after challenge. The oropharynx of pigs affected with porcine respiratory disease complex (PRDC), caused by a combination of viral and/or bacterial pathogens and environmental stressors [7], displayed higher abundance of Moraxella, Veillonella, and Porphyromonas genera compared to healthy pigs [8]. No studies have far investigated the nasal microbiota communities in pigs after infection with respiratory viruses
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call