Group a rotavirus and norovirus genotypes circulating in the northeastern Brazil in the post-monovalent vaccination era

Abstract

Group A rotaviruses (RVA) and noroviruses (NoV) are the leading cause of acute gastroenteritis (AGE) worldwide. Childhood diarrhea deaths and hospital admissions have declined since the introduction of the monovalent (G1P[8]) vaccine (Rotarix(®) [RV1]) in the National Immunization Program in Brazil in 2006. This study aims to investigate the epidemiological profile of NoV and RVA infections from children with AGE in the Northeastern region of Brazil in the post vaccine season. Two-hundred fecal samples collected from children up to 10 years old in Fortaleza, Ceará between 2008-2009 were screened for the presence of RVA and NoV. Positive samples were genotyped and sequenced. The RVA screening revealed 12% prevalence and all RVA strains belonged to G2P[4] genotype. Phylogenetic analysis based on the 11 RVA genome segments sequenced from eight samples revealed a DS-1-like genotype constellation: I2-R2-C2-M2-A2-N2-T2-E2-H2. For NoV screening, the prevalence observed was 17% and the following genotypes were detected: GII.4 (59%), GII.12 (17%), GII.6 (9%), GII.3 (6%), and GII.? (9%). At least four different NoVs genotypes and two RVA G2P[4] variants were identified circulating in the Northeastern region of Brazil. RVA phylogenetic analysis suggests that the RVA G2P[4] strains might have originated from intragenogroup reassortment events. Whether the genetic modifications observed in these contemporary G2P[4] RVA strains may impact the long-term effectiveness of the current vaccination programs remains to be explored. These data reinforce the importance of surveillance for monitoring the emergence of new strains of RVA and NoV and their impact on cases of acute gastroenteritis.

Genetic Diversity of Norovirus Infections, Coinfections, and Undernutrition in Children From Brazilian Semiarid Region

“…In this study, the most prevalent recombinant strain was GII.P16‐GII.3. The presence of the NoV GII.3 strain was reported in a previous study that investigated strains circulating in children who sought medical attention in Northeast Brazil (43). Furthermore, in a surveillance study conducted in Southeast Brazil from 2003 to 2004, GII.3 was the second most frequently detected strain (44).…”

Human norovirus infection in Latin America

“…In the Northern hemisphere, a clearly defined seasonality for HuNoV has been described with the large majority of the clinical cases occurring in winter [88], which gave rise to the infection's old name of 'Winter Vomiting Disease' [68,88]. Although some studies failed to detect such seasonality [32,42,58,83,[89][90][91][92][93], HuNoV infections have been shown to frequently occur mainly from June to October in temperate South American countries, namely Argentina, Chile, Uruguay, Southern Brazil and Paraguay [18,21,43,59,60,85,[94][95][96], similarly to the seasonality observed in Oceania [88,97], and mainly from January to April in temperate countries of the Northern hemisphere [32,44,57,98,99]. These infections tend to predominantly occur in association with the rainy season in tropical Latin American regions [62,74,75,77,79,81,[100][101][102].…”

Rotavirus A Infections in Community Childhood Diarrhea in the Brazilian Semiarid Region During Postvaccination Era

“…Parasites and viruses were found in 22.6% (7/31) and 9.6% (3/31) of the RVA-positive samples, respectively (Table 3). of the genotypes is important in understanding the evolutionary dynamics of RVA (20). However, the majority of the studies focus on RVA infections in hospitalized children (18,(20)(21)(22)(23).…”

“…In the postvaccination era, G2P [4] has been one of the most prevalent genotypes in the samples obtained from hospitalized children in Brazil (21). In Fortaleza, G2P [4] was highly frequent in children with moderate to severe community childhood diarrhea (20). G1-and P [8]-positive samples were clustered with RV1 vaccine.…”

“…We further characterized clinical data, RVA genotypes distribution, VP7 and VP8* phylogenetic analysis, and coinfection patterns of the RVA‐positive samples. In Brazil, RV1 has shown to provide protection against severe morbidity and mortality rates due to RVA (6), and surveillance of the circulation of the genotypes is important in understanding the evolutionary dynamics of RVA (20). However, the majority of the studies focus on RVA infections in hospitalized children (18,20–23).…”