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A recent survey of pigs in Dong Thap province, Vietnam identified a high frequency of enterovirus species G (EV-G) infection (144/198; 72.7%). Among these was a plethora of EV-G types (EV-G1, EV-G6 and four new types EV-G8 to -G11). To better characterize the genetic diversity of EV-G and investigate the possible existence of further circulating types, we performed a larger scale study on 484 pig and 45 farm-bred boar faecal samples collected in 2012, 2014, respectively. All samples from the previous and current studies were also screened for kobuviruses. The overall infection frequency of enteroviruses (EV) remained extremely high (395/484; 81.6%) but with comparable detection rates and viral loads between healthy and diarrhoeic pigs; this contrasted with less frequent detection of EV-G in boars (4/45; 8.9%). EV was most frequently detected in pigs ≤14 weeks old (approximately 95%) and declined in older pigs. Infections with EV-G1 and EV-G6 were most frequent, while less commonly detected types included EV-G3, EV-G4, EV-G8 - EV-G11 and 5 new types (EV-G12 to -G16). In contrast, kobuvirus infection frequency was significantly higher in diarrhoeic pigs (40.9% compared to 27.6%; p=0.01). Kobuviruses also showed contrasting epidemiologies and age associations; a higher prevalence was found in boars (42%) compared to domestic pigs (29%) with the highest infection frequency among pigs >52 weeks old. Although genetically diverse, all kobuviruses identified belonged to species Aichivirus C. In summary, this study confirms infection with EV-G was endemic in Vietnamese domestic pigs and exhibits high genetic diversity and extensive inter-type recombination.