Data analysis
Data from subtype, country, sampling site, and water source were extracted and analyzed. Sample sites were live bird market (LBM), poultry farm (PF), wild bird habitat (WBH), or unknown (UNK). Water sources were drinking water trough (DW), poultry cage water (PCW), sewage (SW), turkey barn water (TBW), hand-wash water (HWW), carcass-wash water (CWW), duck’s environmental water (DEW), or unknown (UNK). The category “unknown” referred to not clearly stated information. Data analysis was conducted using graphs and maps created in RStudio using the ggplot2 package (Wickham, 2016) and Mapcharnet® (https://mapchart.net).