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

Made available in DSpace on 2015-06-12T13:57:51Z (GMT). No. of bitstreams: 2 license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) tatiana_roseetal_IOC_2014.pdf: 862520 bytes, checksum: 3124bc7c8df41b90c55fc26589eb62cf (MD5) Previous issue date: 2014Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.University of Leuven. Rega Institute for Medical Research. Department of Microbiology and Immunology.Laboratory of Clinical and Epidemiological Virology. Leuven, Belgium.University of Leuven. Rega Institute for Medical Research. Department of Microbiology and Immunology.Laboratory of Clinical and Epidemiological Virology. Leuven, Belgium.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Virologia Comparada e Ambiental. Rio de Janeiro, RJ, Brasil.This study aims to: estimate the prevalence of G2P[4] rotaviruses in Brazil between 2001–2011 from patients with acute gastroenteritis; perform phylogenetic analyses of G2P[4] Brazilian strains (from vaccinated and non-vaccinated children) based on VP7 and VP8⁄ encoding genes and analyze the antigenic regions of these proteins comparing with RV1; and assess the full genetic background of eleven selected Brazilian strains. The G2P[4] detection rate among RVA positive samples was 0/157 in 2001, 3/226 (1.3%) in 2002, 0/514 in 2003, 0/651 in 2004, 31/344 (9%)/2005, 112/227 (49%)/2006, 139/211 (66%)/2007, 240/ 284 (85%)/2008, 66/176 (37.5%)/2009, 367/422 (87%)/2010 and 75/149 (50%)/2011. For the VP7 and VP8⁄ encoding genes, 52 sequences were analyzed and shared up to 99% nucleotide identity with other contemporary G2P[4] strains detected worldwide, grouping into different clusters. Most differences inside antigenic epitopes of VP7 and VP8⁄ have been maintained in the G2P[4] Brazilian strains along the years, and all were present before RV1 introduction. Eleven G2P[4] strains (4-vaccinated/7-non-vaccinated) were completely characterized and possessed the typical DS-1-like genotype constellation (G2-P[4]-I2- R2-C2-M2-A2-N2-T2-E2-H2) sharing up to 99% of nucleotide identity with contemporary worldwide strains. Reassortments between Brazilian G2P[4] human strains were observed. In conclusion, the data obtained in the current study suggests that implementation of RV1 vaccination might not influence the genetic diversity observed in G2P[4] analyzed strains. Several factors might have contributed to the increased prevalence of this genotype in Brazil since 2005: the introduction of RV1 into the Brazilian National Immunization Program has resulted in a decrease in the relative prevalence of predominant Wa-like RVA strains facilitating the increase of the heterotypic (DS-1-like) RVA strain G2P[4] in the Brazilian population; the genetic diversity found in different geographical regions throughout the years before, and after the introduction of RV1; the long period of low or no circulation of this genotype in Brazil previous to RV1 introduction could have created favorable conditions for the accumulation of immunological susceptible individuals

Assessment of gastroenteric viruses frequency in a children's day care center in Rio De Janeiro, Brazil: a fifteen year study (1994-2008).

This 15-year study aimed to determine the role of the main viruses responsible for acute infantile gastroenteritis cases in a day care center in the city of Rio de Janeiro, Brazil. From 1994 to 2008, 539 fecal samples were obtained from 23 outbreaks as well as sporadic cases that occurred in this period. The detection of Rotavirus group A (RVA), norovirus (NoV) and astrovirus (AstV) was investigated both by classical and molecular methods of viral detection. RVA was detected by enzymatic immune assay and/or polyacrylamide gel electrophoresis and genotyped by using semi-nested multiplex PCR. NoV and AstV were subsequently tested by real time PCR in all RVA-negative samples and genotyped throughout genome sequencing. Three protocols for molecular characterization of NoV nucleotide sequencing were performed with the partial nucleotide sequencing of genomic regions known as region B (polymerase gen), C and D (capsid gen).Viruses were identified in 47.7% (257/539) of the cases, and the detection rates of RVA, NoV and AstV in16.1% (87/539), 33.4% (151/452), and 6.3% (19/301), respectively. Most gastroenteritis cases were reported in autumn and winter, although NoV presented a broader monthly distribution. Viruses' detection rates were significantly higher among children aged less than 24 months old, although NoV cases were detected in all age groups. RVA genotypes as G1P[8], G9P[8], G2P[4], G3P[8] and G1+G3P[8] and RVA was no longer detected after 2005. NoV characterization revealed genotypes variability circulating in the period as GI.2, GI.3, GI.8 GII.2, GII.3, GII.4, GII.4 variants 2001 and 2006b, GII.6, GII.7, GII.12 and GII.17. AstV genotypes 1, 2, 4 and 5 were also characterized. Those data demonstrate the impact of NoV infection in cases of infantile gastroenteritis, surpassing RVA infection responsible for high morbidity rate in children under five years old