Molecular Epidemiology of Rotavirus among Children in Western Canada:
Dynamic Changes in Genotype Prevalence in Four Consecutive Seasons
Abstract
Rotavirus molecular surveillance remains important in the post vaccine
era in order to monitor the changes in transmission patterns, identify
vaccine induced antigenic changes and discover potentially pathogenic
vaccine related strains. The Canadian province of Alberta introduced
rotavirus vaccination into its provincial vaccination schedule June
2015. To evaluate the impact of this program on stool rotavirus
positivity rate, strain diversity and seasonal trends, we analyzed a
prospective cohort of children with acute gastroenteritis recruited
between December 2014 and August 2018. We identified dynamic changes in
rotavirus positivity and genotype trends during pre- and post- rotavirus
vaccine introduction periods. Genotypes G9P[8], G1P[8],
G2P[4] and G12P[8] predominated consecutively each season with
overall lower rotavirus incidence rates in 2016 and 2017. The
demographic and clinical features of rotavirus gastroenteritis were
comparable among wild type rotaviruses; however, children with
G12P[8] infections were older (P<0.001). Continued efforts
to monitor changes in the molecular epidemiology of rotavirus using
whole genome sequence characterization is needed to further understand
the impact of the selection pressure of vaccination on rotavirus
evolution.