Diversity of rotavirus strains circulating in Northern Brazil after introduction of a rotavirus vaccine: High prevalence of G3P[6] genotype

Abstract

Rotavirus A (RVA) is the most common cause of severe acute gastroenteritis in infants and young children worldwide, causing 453,000 deaths annually. In Brazil, the most frequent genotype identified was G1 during almost three decades in the pre-vaccination period; however, after anti-rotavirus vaccine introduction, there was a predominance of G2 genotype. The aim of this study was to determine the G and P genotypes of rotaviruses isolated from children under 5 years of age with acute gastroenteritis in the Northern region of Brazil, and discuss the emergence of G3P[6] genotype. A total of 783 stool specimens were obtained between January 2011 and March 2012. RVA antigen was detected in 33% (272/783) of samples using a commercial enzyme-linked immunosorbent assay and type-specificity was determined by reverse-transcription polymerase chain reaction. The most common binary combination was G2P[4], representing 41% of cases, followed by G3P[6] (15%), G1P[8] (8%), G3P[8] (4%), G9P[8] (3%), and G12P[6] (2%). G3P[6] strains were analyzed further and phylogenetic analysis of VP7 gene showed that G3 strains clustered into lineage I and showed a high degree of amino acid identity with vaccine strain RV3 (95.1-95.6%). For VP4 sequences, G3P[6] clustered into lineage Ia. It was demonstrated by the first time the emergence of unusual genotype G3P[6] in the Amazon region of Brazil. This genotype shares neither VP7 nor VP4 specificity with the used vaccine and may represent a challenge to vaccination strategies. A continuous monitoring of circulating strains is therefore needed during the post-vaccine era in Brazil.

Prevalence and diversity of rotavirus A genotypes cirulating in Turkey during a 2‐year sentinel surveillance period, 2014‐2016

“…Despite the high number of different G and P types, the current study showed that 90% of the rotavirus strains belonged to one of the five most common G types (G1, G2, G3, G4, and G9), and 97.5% belonged to one of the two main P types (P[8] and P[4]). Consistent with our data, the genotyping of rotavirus strains from different countries has indicated that more than 85% of strains can be classified into these five G types and three P types (P[8], P[4], and P[6]) . In addition to these common genotypes, which accounted for the majority of the isolates, 21.5% of the isolates were classified into 20 different uncommon types, and about 1% of the isolates carried mixed genotypes.…”

Whole-genomic analysis of 12 porcine group A rotaviruses isolated from symptomatic piglets in Brazil during the years of 2012–2013

“…Noteworthy, among the human G11 strains analyzed to date by whole-genome sequencing, most of the genes of the G11P[6] strain were closely related to those of porcine, human-porcine or bovine-porcine reassortant strains . Recently, a G3P[6] genotype strain was detected in humans at Amazonas and Acre states only (da Silva Soares et al, 2014). In Latin America, G3P[6] strains were detected at a frequency of 0.2% in humans with RVA infections (Linhares et al, 2011), allowing them to be considered a genotype found rarely in humans and never before described in Brazilian pigs.…”

Prevalence and genomic characterization of G2P[4] group A rotavirus strains during monovalent vaccine introduction in Brazil

“…G2P [4] has been the most common genotype detected in Brazil after the onset of RV1 mass vaccination (Gurgel et al, 2007;de Oliveira et al, 2008;Nakagomi et al, 2008;Leite et al, 2008;Carvalho-Costa et al, 2009da Silva Soares et al, 2014). The emergence of this genotype has motivated a great discussion and a relationship between this phenomenon and RV1 vaccination has been proposed suggesting that universal vaccination would have exerted selective pressure on circulating RVAs, selecting G2P [4] (Gurgel et al, 2007;Nakagomi et al, 2008;.…”