Molecular Characterization of the Porcine Epidemic Diarrhea Virus TW4/2014 in Taiwan

Infections by Porcine Epidemic Diarrhea Virus (PEDV) have been shown to be significantly correlated with fatal diarrhea in suckling piglets. Although PEDV was first identified in Europe, since late 2010, it has become increasingly problematic on several continents, including Asia, North America, and South America. Since late 2013, several outbreaks of PEDV have emerged in Taiwan. Analysis of the partial PEDV S gene sequences in these strains revealed that these outbreaks were in the same clade as US strains of PEDV. To elucidate the molecular characterization of the Taiwanese and reference strains in greater detail, the full length of a local isolate (TW4/2014) that was derived from a suckling piglet was sequenced using next-generation sequencing techniques and compared to other worldwide strains. The complete genome size of TW4 (27,966 nucleotides excluding the 5' leader sequence) appears to be almost identical (99.9%) to several of the 2013 US strains. Our results indicate that the recent PEDV isolates from Taiwan share a common evolutionary origin with US-like PEDV strain from several countries (South Korea, Canada, Mexico, and Peru) and US strains.