Group A Rotavirus Genotypes among Calf Herds in Southwest Nigeria and Implications for Human Rotavirus Vaccines’ Efficiency

Abstract

Rotaviruses have been widely reported to be associated with diarrhea in humans but fewer studies abound on other mammalian species. This prospective study was conducted to detect and characterize Rotaviruses from freely ranged migratory herds of cattle in Ekiti and Ondo states, Nigeria with a view to further expanding knowledge on rotaviruses, possible animal-human interspecies transmission and impacts on vaccine efficiency. By convenience sampling, between September 2014 and February 2015, stool samples from 120 calves, comprising settled and migratory herds of cattle were obtained and examined for group A rotaviruses using Certest® Quadruple Enzyme Immuno Assay. Rotavirus genomes were isolated by extraction from the positive samples, reverse transcribed and amplified by One-Step reverse transcription polymerase chain reaction (RT-PCR), and genotyped by semi-nested multiplex PCR. Representative PCR products of the genotyped samples were purified and sequenced using Sanger method. The generated query sequences were queried to the GenBank to retrieve similar sequences for pairwise alignment by Clus-talW. Phylogenetic analyses by Neighbour-joining method were conducted at 1000 bootstrap replicates to obtain phylograms using MEGA 6 software. Fifteen samples (15/120: 12.5%) were positive for rotavirus. No statistically significant association existed between rotavirus infection and gender of the calves (χ 2 = 0, df = 1, p = 1). Eight samples (8/15: 53.3%) were successfully genotyped where the G1, G5, G9, G10, G12, and P[6] were detected. Nucleotide Sequencing of the VP7 and VP4 genes of the genotyped samples confirmed strains G1P[6], G10P[6], and G12P[6] with 58%-100% nucleotide identity within these viruses. Phylogenetic analysis revealed 2 possible transmissions from India and Honduras. Bovine rotaviruses were detected in freely ranged and settled calf herds in southwestern Nigeria at a rate of 12.5%. The strains How to cite this paper: Babalola, M.O.

Epidemiological study of Rotavirus infection in the diarrheic neonatal calves

“…The present study showed that 7 (8.54%) of 82 diarrheic fecal samples of investigated calves were positive by ICA. Our result of ICA was lower than those of other studies [1,12,13] in which rate of Rotavirus infection in serologically positive enteric calves by ICA was 15.63%, 12.50% and 10%, respectively.…”

Epidemiological Study of Rotavirus Infection in the Diarrheic Neonatal Calves

“…The present study showed that 7 (8.54%) of 82 diarrheic fecal samples of investigated calves were positive by ICA. Our result of ICA was lower than those of other studies [2,14,15] in which rate of Rotavirus infection in serologically positive enteric calves by ICA was 15.63%, 12.50% and 10%, respectively. Such variations in rate of Rotavirus infection in examined calves may be due to geographical variation, hygienic measures, environmental conditions, difference in timing of samples collection, clinical phase of the disease is a suitable time for sampling to obtain the optimum result from a test [11].…”

Clinical Study with Rapid Serological Detection of Rotavirus Infection in Diarrheic Neonatal Calves

“…They indicated that percentage of Rotavirus seropositive enteric cases was 35.25%, and 53.6%, respectively. Contrariwise,[10,18,19] indicated that rate of Rotavirus infection in enteric calves was 36%, 15.63% and 12.50%, respectively. Such variations in rate of infection of Rotavirus in enteric calves may be attributed to geographical variation, difference in timing of samples collection, clinical phase of the disease is a suitable time for sampling to obtain the optimum result from a test, hygienic measures and environmental conditions.…”