Porcine Astrovirus Detection and Characterization in Healthy and Diarrheic Pigs from Haryana, India

Background: Porcine astrovirus (PAstV) is an emerging pathogen detected from the feces of both healthy and diarrheic pigs with limited studies comparing the presence of PAstV and diarrhea in pigs. PAstV has been reported worldwide with a few reports from India. In addition, there are limited reports on variation in the amino acid sequence of the ORF2 region, which codes for viral capsid protein. The present study was aimed to study the presence of PAstV, association with diarrhea in pigs of various age groups and its molecular characterization from Haryana, a northern Indian state. Methods: A total of 176 rectal swabs of pigs were collected from different parts of Haryana. The samples were screened for PAstV by RT-PCR of the partial ORF1b/ORF2 genomic region. The positive samples were characterized by molecular typing and phylogenetic analysis. Result: In the present study, PAstV was detected in pigs in 16.47% of fecal samples, including 21/127 (16.53%) diarrheic and 8/49 (16.32%) non-diarrheic. The results indicated that weaning piglets were more susceptible to PAstV infection followed by suckling piglets. The phylogenetic analysis revealed the circulation of PAstV4 and PAstV2 lineages in Haryana. The study revealed endemic presence of virus in the region with high genetic diversity among the PAstV strains, suggesting a wide range of heterogeneity.