Species-specific emergence of H7 highly pathogenic avian influenza virus is driven by intrahost selection differences between chickens and ducks
Fig 5
H7N7-LPFLAGtag is predominantly shed from ducks co-inoculated with H7N7-HPHAtag and H7N7-LPFLAGtag despite detection of H7N7-HPHAtag in tissues at 3 dpi.
(A) H7N7-HPHAtag and H7N7-LPFLAGtag RNA quantification in oropharyngeal (OP) and cloacal (CL) swabs from six co-inoculated ducks. Viral RNA amounts were determined by HPAIV/LPAIV differentiating RT-qPCR targeting the HA cleavage site and expressed as 40-cycle threshold (Ct). (B) Infectious virus titers in the swabs from panel (A). Titers are depicted as PFU/mL as measured by the HPAIV/LPAIV differentiating plaque assay. (C) H7N7-HPHAtag and H7N7-LPFLAGtag RNA quantification in tissues harvested at 3 dpi as determined by HPAIV/LPAIV differentiating RT-qPCR targeting the HA cleavage site and expressed as 40-Ct normalized/gram tissue. The dotted lines distinguish tissues from the respiratory, digestive, and miscellaneous systems. (D) Infectious virus titers tissues from panel (C), depicted as PFU/gram tissue as determined by the HPAIV/LPAIV differentiating plaque assay. Dotted lines are similar to (C).