GI-16 lineage (624/I or Q1), there and back again: The history of one of the major threats for poultry farming of our era

Franzo, Giovanni; Cecchinato, Mattia; Tosi, Giovanni; Fiorentini, Laura; Faccin, Francesca; Tucciarone, Claudia Maria; Trogu, Tiziana; Barbieri, Ilaria; Massi, Paola; Moreno, Ana

The time-calibrated spreading process provided further information. Particularly, GI-16 lineage was limited to Italy until approximately the late 1980s, when a transmission to China was estimated (Fig 4) . Thereafter, the virus migrated from China to other Asian countries (i.e. Taiwan) in the late 1990s, and in South America at the beginning of the new millennium, where it quickly spread among countries. An additional transmission from China to Middle East (Egypt) was predicted about in 2010. The location posterior probability was constantly high (i.e. >0.9) with the exception of just few ancestral nodes (S1 Fig), whose ancestral country could not be confidently identified. For those particular ancestral nodes, differences were also observed among independent runs. However, this uncertainness is mainly on local base (e.g. China vs Taiwan or among South American countries) and does not affect the overall interpretation of GI-16 spreading pattern.