A novel highly divergent enteric calicivirus in a bovine calf, India

Abstract

Abstract A novel highly divergent bovine calicivirus was identified in an Indian calf experiencing enteritis. The whole genome sequencing revealed distinct amino acid motifs in the open reading frame (ORF1) polyprotein, which are unique to caliciviruses. Phylogenetic analysis linked it with Nebovirus, a genus within the Caliciviridae family, showing only 38.5% sequence identities, emphasizing the need for separate taxonomic classification. Furthermore, in-house designed and optimized reverse transcription polymerase chain reaction (RT-PCR) assay screening of 120 archived bovine diarrhoeic fecal samples, 40 each from the Indian states of Uttar Pradesh, Haryana and Himachal Pradesh, revealed frequent circulation of these divergent caliciviruses in the Indian bovine population, with an overall positivity rate of 64.17% (77/120). This underscores the importance of conducting a comprehensive investigation into the prevalence of these divergent caliciviruses, and assessing their associations with other pathogens responsible for enteritis in India.