Molecular characterization of group A rotavirus (RVA) strains detected in bovine and porcine species: Circulation of unusual rotavirus strains. A study from western, India.

Abstract

Group A rotaviruses (RVA) are considered as important causative agents of diarrhea in both human and animal species. Fecal specimens (n=300) were collected from both diarrheic and healthy animals during the year 2009 from animal farms from Nagpur (Maharashtra), Western India. RVA antigen was detected by ELISA in 3.1-25% and 72% in bovine and porcine species, respectively. Genotyping based on VP6, VP7 and VP4 of RVA-positive samples showed predominance of genotype I-1 (63%) and genotype I-2 (37%), G4 (45.5%) and G10 (27.3%) genotypes, P[6] (72.7%) and P[8] (18.1%) genotypes, respectively. Other RV genotypes such as G1(4.5%), G2(9.1%), G3(4.5%) and mixed infections (9.1%) were detected at low level. Predominance of unusual G-P combinations (9/23, 39.1%) were observed. Circulation of G2P[8] and mixed infections with G1, G3, P[6] and G1, P[8], P[6]) are reported in porcine species for the first time in Western India. In conclusion the present study highlights the circulation of unusual G-P combinations and VP6 genogroup specificities of human RVA strains indicative of possible interspecies transmission and reassortment events in animal species. The study further warrants utmost need for such surveillance studies across the country to understand the role of animals as genetic reservoirs for the emergence of RVA strains pathogenic for humans. Keywords: rotaviruses; genotypes; unusual G-P types; animals.