Human G3P[4] rotavirus obtained in Japan, 2013, possibly emerged through a human-equine rotavirus reassortment event

Area of Science:

• Virology
• Molecular Biology
• Public Health

Background:

• Group A rotaviruses are a leading cause of severe diarrheal disease in infants and young children worldwide.
• Rotavirus strains exhibit significant genetic diversity, with frequent emergence of novel genotypes through reassortment.
• Surveillance of rotavirus strains is crucial for understanding epidemiology and informing vaccine strategies.

Purpose of the Study:

• To characterize the full genome of novel rotavirus strains detected in children with acute diarrhea in Sendai, Japan.
• To investigate the genetic origins and potential reassortment events of these newly identified strains.

Main Methods:

• Whole-genome sequence analysis was performed on two novel rotavirus strains.
• Nucleotide sequence identities and phylogenetic relationships were analyzed using established bioinformatics tools.
• Comparison with existing human and animal rotavirus strains in public databases.

Main Results:

• Two novel G3P[4] rotavirus strains were identified.
• Whole-genome sequencing revealed a unique genotype constellation: G3-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2.
• The VP7 gene showed high similarity to an equine rotavirus from India, while other gene segments were related to human rotaviruses.

Conclusions:

• The findings suggest a potential reassortment event between human and equine rotaviruses.
• This highlights the possibility of interspecies transmission and genetic exchange in rotavirus evolution.
• Continued genomic surveillance is essential to monitor the emergence of novel rotavirus strains and their public health implications.