Unusual rotavirus genotypes in humans and animals with acute diarrhoea in Northeast India

Abstract

Rotavirus (RV) infection causes acute infantile diarrhoea in humans and animals and remains a major concern for vaccine development. The close proximity of humans to animals may foster cross-species infection resulting in the emergence of novel/unusual strains by genetic reassortment. In this study, we characterized 500 diarrhoeal samples for group A rotaviruses (RVA) from children (n = 290), piglets (n = 95) and calves (n = 115) in Northeast India during 2012-2013. The data showed that 142/500 (28·4%) faecal samples were positive for RVA with the highest level of infection detected in piglets (57/142, 40·1%) followed by children (51/142, 35·9%) and calves (34/142, 23·9%). Sequence-based G- and P-typing showed G1P[8] (25%) and G1P[7] (35%) were the prevailing genotypes in both humans and animals. Single cases of unusual genotypes, i.e. G9P[8], G5P[8] in humans and G1P[13], G1P[23] and G3P[7] in animals were also identified. Cluster analyses of the sequences showed regional strains were genetically closer to their homologous strains. However, human G5P[8] and porcine G1P[8] strains showed homology to heterologous hosts of their prototype strains. The subsequent global spread of unusual RV strains may result in their establishment over time, presenting challenges to future vaccine evaluation programmes. More studies on emerging genotypes are required to elucidate how RVA strains evolve post-vaccination. This study supports the need for continuous surveillance of RVA infections after detecting from diverse hosts in a common setting.

Rotavirus: Genetics, pathogenesis and vaccine advances

“…Because of the segmented nature of the RV genome, novel strains can arise by reassortment during coinfection. The unusual strains are associated with 4.9% of total RV infections all over the world . Regionally, they are responsible for 14% of cases in Asia, 27% in Africa, 11% in South America, 5% in North America, 1.4% in Europe, and 0.1% in Australia …”

“…The unusual strains are associated with 4.9% of total RV infections all over the world. 42,43 Regionally, they are responsible for 14% of cases in Asia, 27% in Africa, 11% in South America, 5% in North America, 1.4% in Europe, and 0.1% in Australia. 44 A rare DS-1 like G1P [8] is recently reported in Thailand, Japan, and Vietnam showing reassortment between human and animal strains.…”

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

“…In India, circulation of mainly G6 (25-35%), G10 (50-60%) and G3 (10.2%) genotypes of bovine RV and G6 and G12 genotypes of porcine RVs have been reported (Ghosh et al, 2007;Manuja et al, 2008;Sharma et al, 2009;Ghosh et al, 2015). These findings suggest that interspecies transmission of rotaviruses between humans and animals or animals to animals might take place in nature (Nagai et al, 2015;Theuns et al, 2015;Chakraborty et al, 2016). Accordingly, animal RVAs have been considered to be of great concern for zoonotic potential and resulting in economic losses in commercial cattle farms and piggeries.…”

Whole genome analysis of selected human and animal rotaviruses identified in Uganda from 2012 to 2014 reveals complex genome reassortment events between human, bovine, caprine and porcine strains

“…A study in Southern India found evidence of human-to-animal transmission of a G2 RVA strain [26]. Another study in Northern India found possible reassortment between genes of animals and human RVAs resulting in circulation of unusual rotavirus genotypes [27]. …”