This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.
This week, we are sharing a study from Dr. Andres Diaz and the Torremorell lab.
Key points
- The diversity of influenza A viruses in growing pigs is dynamic
- Influenza A viruses can replicate as a swarm of viruses that are identical, closely related to each other (>99%), or clearly distinct (H1 vs. H3 subtypes)
- Influenza A viruses of the same genotype can re-infect pigs within a short period of time.
132 3-week old piglets selected at weaning and placed in a wean-to-finish farm were sampled weekly for 15 weeks (n=2080 samples). Samples were tested by RT-PCR and the complete genome of influenza was obtained from 93 samples using next generation sequencing.
Two epidemic waves of IAV infection were detected with 3 distinct viral groups (VG swarms) found (VG1, VG2 and VG3). An H1 gamma (VG1) dominated the first outbreak, an H3 (VG3) dominated the second outbreak and an H1 beta (VG2) was only recovered when none of the two other viruses dominated.
The complete version of this study can be found online in open-access.