title: Phylogenetic analysis of G1P[6] group A rotavirus strains detected in Northeast Brazilian children fully vaccinated with Rotarix™.
abstract: In 2009 the World Health Organization recommended the use of group A rotavirus (RVA) vaccines in all national immunization programs (NIPs) in order to control severe RVA gastroenteritis disease. In Brazil, Rotarix™ was introduced in the NIP in March 2006, and a significant reduction in mortality rates among children ≤ 5 years old was observed, especially in the Northern and Northeastern Brazil. In the current study the 11 gene segments of six Brazilian G1P[6] RVA strains, isolated in 2009 and 2010 from vaccinated children, were analyzed in order to investigate if the genetic composition of these strains might help to elucidate why they were able to cause acute gastroenteritis in vaccinated children. All six Brazilian RVA strains revealed a complete Wa-like genotype constellation: G1-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1. Phylogenetic analysis showed that all six strains were nearly identical and showed a close genetic relationship with contemporary typical human Wa-like RVA strains. These results suggests that the fact that these strains were able to cause acute gastroenteritis in vaccinated children is likely not due to the genetic background of the strains, but rather to other factors such as host relating factors, co-infecting pathogens or vaccine efficacy. P[6] RVA strains are detected rather occasionally in humans in most regions of the world, except for South Asia and Sub-Saharan Africa. However, recently two studies conducted in Brazil showed the circulation of G12P[6] and G2P[6]. This is the first report on the detection and complete genome analyses of G1P[6] RVA strains in Brazil. Surveillance studies will be crucial to further investigate the prevalence of this genotype in the Brazilian population, and the efficacy of current licensed vaccines, which do not contain the P[6] genotype.
authors.affiliation: Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Av. Brazil 4365, Manguinhos, 21040-360 Rio de Janeiro, RJ, Brazil. Electronic address: marie@ioc.fiocruz.br.
authors.forename: Mariela Martínez
authors.initials: MM
authors.lastname: Gómez
authors.forename: Marcelle Figueira Marques
authors.initials: MF
authors.lastname: da Silva
authors.forename: Mark
authors.initials: M
authors.lastname: Zeller
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Heylen
authors.forename: Jelle
authors.initials: J
authors.lastname: Matthijnssens
authors.forename: Maria Yuri Travassos
authors.initials: MY
authors.lastname: Ichihara
authors.forename: Tatiana Lundgren
authors.initials: TL
authors.lastname: Rose
authors.forename: Eduardo
authors.initials: E
authors.lastname: de Mello Volotão
authors.forename: Jose Paulo Gagliardi
authors.initials: JP
authors.lastname: Leite
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002675:Child, Preschool; D005243:Feces / Q000821:virology; D016679:Genome, Viral / Q000235:genetics; D005838:Genotype; D006801:Humans; D007223:Infant; D010802:Phylogeny; D012401:Rotavirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology / Q000517:prevention & control / Q000821:virology*; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated
chemical_list: C492457:RIX4414 vaccine; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated
keywords: Complete genome analysis; G1P[6]; Group A rotavirus; Phylogenetic analysis; Rotarix(™)