Genomic Constellation of Human Rotavirus G8 Strains in Brazil over a 13-Year Period: Detection of the Novel Bovine-like G8P[8] Strains with the DS-1-like Backbone

Abstract

Rotavirus (RVA) G8 is frequently detected in animals, but only occasionally in humans. G8 strains, however, are frequently documented in nations in Africa. Recently, an increase in G8 detection was observed outside Africa. The aims of the study were to monitor G8 infections in the Brazilian human population between 2007 and 2020, undertake the full-genotype characterization of the four G8P[4], six G8P[6] and two G8P[8] RVA strains and conduct phylogenetic analysis in order to understand their genetic diversity and evolution. A total of 12,978 specimens were screened for RVA using ELISA, PAGE, RT-PCR and Sanger sequencing. G8 genotype represented 0.6% (15/2434) of the entirely RVA-positive samples. G8P[4] comprised 33.3% (5/15), G8P[6] 46.7% (7/15) and G8P[8] 20% (3/15). All G8 strains showed a short RNA pattern. All twelve selected G8 strains displayed a DS-1-like genetic backbone. The whole-genotype analysis on a DS-1-like backbone identified four different genotype-linage constellations. According to VP7 analysis, the Brazilian G8P[8] strains with the DS-1-like backbone strains were derived from cattle and clustered with newly DS-1-like G1/G3/G9/G8P[8] strains and G2P[4] strains. Brazilian IAL-R193/2017/G8P[8] belonged to a VP1/R2.XI lineage and were grouped with bovine-like G8P[8] strains with the DS-1-like backbone strains detected in Asia. Otherwise, the Brazilian IAL-R558/2017/G8P[8] possess a “Distinct” VP1/R2 lineage never previously described and grouped apart from any of the DS-1-like reference strains. Collectively, our findings suggest that the Brazilian bovine-like G8P[8] strains with the DS-1-like backbone strains are continuously evolving and likely reassorting with local RVA strains rather than directly relating to imports from Asia. The Brazilian G8P[6]-DS-1-like strains have been reassorted with nearby co-circulating American strains of the same DS-1 genotype constellation. However, phylogenetic analyses revealed that these strains have some genetic origin from Africa. Finally, rather than being African-born, Brazilian G8P[4]-DS-1-like strains were likely imported from Europe. None of the Brazilian G8 strains examined here exhibited signs of recent zoonotic reassortment. G8 strains continued to be found in Brazil according to their intermittent and localized pattern, thus, does not suggest that a potential emergence is taking place in the country. Our research demonstrates the diversity of G8 RVA strains in Brazil and adds to the understanding of G8P[4]/P[6]/P[8] RVA genetic diversity and evolution on a global scale.

Predominance of DS‐1‐like G8P[8] rotavirus reassortant strains in children hospitalized with acute gastroenteritis in Thailand, 2018–2020

“…40 The emergence of this unusual G8P [8] in Chiang Rai, Thailand may be a consequence of global vaccine introduction, and this phenomenon has been recently described in multiple reports. 6,7,30,31,35,38 Full genome analysis of four representative G8P [8] strains in the present study exhibited the constellation of genogroup II with the DS-1-like G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2, similar with recent RVA investigations from several countries. 7,8,21,30,32,34,35,37,38,[40][41][42] Genetic analysis of the VP7 genes demonstrated that 14 G8P [8] strains in this study and 13 G8P [8] strains previously described in Thailand and China contained two amino acid residues (A125S and N147D) in the neutralizing epitopes different from the prototype G8 strains (Figure 2A).…”

“…6,7,30,31,35,38 Full genome analysis of four representative G8P [8] strains in the present study exhibited the constellation of genogroup II with the DS-1-like G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2, similar with recent RVA investigations from several countries. 7,8,21,30,32,34,35,37,38,[40][41][42] Genetic analysis of the VP7 genes demonstrated that 14 G8P [8] strains in this study and 13 G8P [8] strains previously described in Thailand and China contained two amino acid residues (A125S and N147D) in the neutralizing epitopes different from the prototype G8 strains (Figure 2A). Of the previous 13 G8P[8] strains, they were identified from hospitalized and outpatient adults in Thailand 43 and hospitalized children in Thailand 12 and China.…”

“…12 Interestingly, G8P [8] emerged as a major genotype for the first time in Thailand with the highest incidence rate of 68.4% in 2018-2019 and 81.2% in 2019-2020 (Table 1). Similarly, increasing predominance or outbreaks of G8P [8] out of Thailand were reported during the past decade in several countries, including Japan in 2014-2018 (9.5%-66.0%), [30][31][32][33][34] Korea in 2015-2020 (42.2%), 7 Singapore in 2016 (60.0%), 35 Chile in 2016-2017 (48.0%), 36 the Czech Republic in 2016-2019 (9.3%), 37 Brazil in 2017 (20.0%), 38 Argentina in 2018 (18.1%), 6 Gabon in 2018-2019 (15.0%), 39 and China in 2020-2021 (40.0%). 40 The emergence of this unusual G8P [8] in Chiang Rai, Thailand may be a consequence of global vaccine introduction, and this phenomenon has been recently described in multiple reports.…”

Assessment of Gastroenteric Viruses in Marketed Bivalve Mollusks in the Tourist Cities of Rio de Janeiro, Brazil, 2022

“…G8 genotype strains, also detected in this study, are considered rare or uncommon [ 102 ]. Recently, Medeiros et al [ 103 ] suggested that Brazilian bovine-like G8P[8] strains with DS-1-like backbone strains are continuously evolving and probably reassorting with local RVA strains rather than directly related to Asian imports. However, the increase in G8 detection outside Africa may indicate that G8 strains are emerging worldwide and that this genotype should be monitored [ 104 , 105 ].…”