Name
Development and application of a novel primer set for routine detection of G3 Equine-Like strains and Molecular characterization of the VP7 gene during the 2023–2024 pediatric rotavirus-positive cases in Córdoba, Argentina.
Presenter
Verónica Emilse Prez, Instituto de Virología Dr. J. M. Vanella - Facultad de Ciencias Medicas Universidad Nacional de Córdoba
Co-Author(s)
Remigio Arteaga 1*; Gonzalo M. Castro 2*; Ariana M. Cachi 3; María de los Ángeles Marinzalda 3; Miguel O. Giordano 1; M. Beatriz Isa 4; Gabriela Barbás 2; Gisela Masachessi 1,5; Silvia V. Nates 1; Verónica E. Prez 1,5.
1 Instituto de Virología “Dr. J.M. Vanella” - Facultad de Ciencias Médicas, Universidad Nacional de Córdoba.
2 Departamento Laboratorio Central - Ministerio de Salud de la Provincia de Córdoba.
3 Instituto Nacional de Medicina Aeronáutica y Espacial - Universidad Nacional de la Defensa - FAA.
4 Clínica Universitaria Reina Fabiola de la ciudad de Córdoba.
5 Consejo Nacional de Investigaciones Científicas y Técnicas - CONICET.
Abstract Category
Epidemiology, Evolution, and Diversity
Abstract
Rotavirus is a dsRNA virus with a segmented genome encoding multiple proteins, including VP7, which determines Gx genotype. Common human genotypes include G1-G4, G8, G9, and G12. Since 2015, a new G3 Equine-Like strain, with 91% homology to the equine G3 strain, has been circulating in multiple countries, but it is not included in the WHO’s detection methods. In Argentina, initial results from the 2023 rotavirus-positive cases indicated high G1 circulation despite the Rotarix vaccination program. However, sequencing revealed these amplicons as G3 Equine-like, confirming mis-genotyping at the G1 amplicon size (genotyping based on the WHO 2009
methodology). The study objective was to design a novel primer set specific to G3 Equine-Like strains for routine detection. This approach was employed to molecularly characterize the G3 Equine-Like strains circulating in Córdoba, Argentina, during the 2023–2024 pediatric gastroenteritis rotavirus-positive cases. Sequences from NCBI Database, publications, and previously genotyped VP7 from Argentina were used to design a primer set targeting the VP7 gene. The primer set’s specificity was evaluated against other rotavirus genotypes, as well as enteric bacteria and viruses. The primers produced a single 230 bp band on agarose gel with no cross-reactivity. Samples originally identified as G1 were confirmed as G3 Equine-Like, emphasizing its key etiological role in rotavirus cases. Sequencing revealed three nucleotide changes within the ORF region regarding global sequences. The implementation of novel primer set proved to be a powerful tool for routine G3 Equine-Like rotavirus detection, however the impact of nucleotide changes needs further assessment.
methodology). The study objective was to design a novel primer set specific to G3 Equine-Like strains for routine detection. This approach was employed to molecularly characterize the G3 Equine-Like strains circulating in Córdoba, Argentina, during the 2023–2024 pediatric gastroenteritis rotavirus-positive cases. Sequences from NCBI Database, publications, and previously genotyped VP7 from Argentina were used to design a primer set targeting the VP7 gene. The primer set’s specificity was evaluated against other rotavirus genotypes, as well as enteric bacteria and viruses. The primers produced a single 230 bp band on agarose gel with no cross-reactivity. Samples originally identified as G1 were confirmed as G3 Equine-Like, emphasizing its key etiological role in rotavirus cases. Sequencing revealed three nucleotide changes within the ORF region regarding global sequences. The implementation of novel primer set proved to be a powerful tool for routine G3 Equine-Like rotavirus detection, however the impact of nucleotide changes needs further assessment.