Productive influenza infection can be improved by cooperation and this varies between viral strains and hosts. By quantifying the rates of reassortment and virus production using several methods, including single-cell sequencing, the authors find that isolates of the avian H9N2 influenza subtype are dependent on infections with a second virus, but only in mammalian cells and not in avian cells. These findings are supported by in vivo experiments in guinea pigs and quail. The authors find indications that this type of cooperation between influenza A viruses depends on the RNA polymerase subunit PA.
- Kara L. Phipps
- Ketaki Ganti
- Anice C. Lowen
