Detection and genetic characterization of porcine astrovirusesin piglets with and without diarrhea in Thailand

Abstract

AbstractPorcine astrovirus (PAstV) is widely distributed and highly prevalent among pigs, nevertheless its clinical significanceremains unclear as it can be detected in both diarrheic and in healthy pigs. Information about the prevalence, clinical significanceand molecular characterization of PAstV in Thailand is not available. This study investigated the prevalence of PAstVin 488 fecal samples collected from piglets with and without diarrhea in 28 pig farms in northern and central parts of Thailandusing RT-PCR. The overall prevalence of PAstV infection was 6.5% (32/488), of which 21/251 (8.4%) were in diarrheic and11/237 (4.6%) were in healthy pigs. Of 32 positive samples, 46.9% were positive for PAstV alone whereas 53.1% were coinfectedwith porcine group A rotavirus (PRVA). A phylogenetic analysis of the partial RNA-dependent RNA polymerase/capsid genes revealed two lineages of PAstV strains detected in this study. PAstV4 was the most dominant genotype (92%),followed by PAstV2 (8%). This study revealed for the first time that PAstV4 and PAstV2 were circulating in Thailand withPAstV4 as the most dominant genotype in pig herds in northern and central parts of Thailand