First report of multiple lineages of dengue viruses type 1 in Rio de Janeiro, Brazil

<p>Abstract</p> <p>Background</p> <p>In Brazil dengue has been a major public health problem since DENV-1 introduction and spread in 1986. After a low or silent co-circulation, DENV-1 re-emerged in 2009 causing a major epidemic in the country in 2010 and 2011. In this study, the phylogeny of DENV-1 strains isolated in RJ after its first introduction in 1986 and after its emergence in 2009 and 2010 was performed in order to document possible evolutionary patterns or introductions in a re-emergent virus.</p> <p>Findings</p> <p>The analysis of the E gene sequences demonstrated that DENV-1 isolated during 2009/2010 still belong to genotype V (Americas/Africa) but grouping in a distinct clade (lineage II) of that represented by earlier DENV-1 (lineage I). However, strains isolated in 2011 grouped together forming another distinct clade (lineage III).</p> <p>Conclusions</p> <p>The monitoring of DENV is important to observe the spread of potentially virulent strains as well to evaluate its impact over the population during an outbreak. Whether explosive epidemics reported in Brazil caused mainly by DENV-1 was due to lineage replacement, or due the population susceptibility to this serotype which has not circulated for almost a decade or even due to the occurrence of secondary infections in a hyperendemic country, is not clear. This is the first report of multiple lineages of DENV-1 detected in Brazil.</p

Circulation of Different Lineages of Dengue Virus 2, Genotype American/Asian in Brazil: Dynamics and Molecular and Phylogenetic Characterization

The American/Asian genotype of Dengue virus type 2 (DENV-2) was introduced into the Americas in the 80′s. Although there is no data showing when this genotype was first introduced into Brazil, it was first detected in Brazil in 1990. After which the virus spread throughout the country and major epidemics occurred in 1998, 2007/08 and 2010. In this study we sequenced 12 DENV-2 genomes obtained from serum samples of patients with dengue fever residing in São José do Rio Preto, São Paulo (SJRP/SP), Brazil, in 2008. The whole open reading frame or envelope sequences were used to perform phylogenetic, phylogeographic and evolutionary analyses. Isolates from SJRP/SP were grouped within one lineage (BR3) close to isolates from Rio de Janeiro, Brazil. Isolates from SJRP were probably introduced there at least in 2007, prior to its detection in the 2008 outbreak. DENV-2 circulation in Brazil is characterized by the introduction, displacement and circulation of three well-defined lineages in different times, most probably from the Caribbean. Thirty-seven unique amino acid substitutions were observed among the lineages, including seven amino acid differences in domains I to III of the envelope protein. Moreover, we dated here, for the first time, the introduction of American/Asian genotype into Brazil (lineage BR1) to 1988/89, followed by the introduction of lineages BR2 (1998–2000) and BR3 (2003–05). Our results show a delay between the introduction and detection of DENV-2 lineages in Brazil, reinforcing the importance and need for surveillance programs to detect and trace the evolution of these viruses. Additionally, Brazilian DENV-2 differed in genetic diversity, date of introduction and geographic origin and distribution in Brazil, and these are important factors for the evolution, dynamics and control of dengue.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq Grant )Fundação de Amparo à Pesquisa do Estado de São PauloFundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG grant

Analysis of the relative frequency of Influenza A(H1N1)pdm virus NA mutations identified in this study (A–E) that were reported in the GenBank in 2009 (April to December) in Mexico (n = 181) and the rest of the world (n = 5,032).

<p>Dotted lines represent world-wide isolates, whereas solid lines represent Mexican isolates. Red and blue lines represent alternate alleles. The 912 G/A mutation was not found neither in Morelos nor in Mexican GenBank reports, but was identified elsewhere (<b>F</b>). The absolute (<b>G</b>) and relative (<b>H</b>) number of isolates used for this analysis is shown for Mexico (solid black line) and world-wide isolates (dotted black line). Note that in June, July and August, only 3, 6 and 1 Mexican isolates were reported in the IVR, respectively.</p

Overall metrics and results of the sequencing run.

<p>Na. Not applicable.</p

Genetic diversity of Influenza A(H1N1)pdm virus in the State of Morelos (2009).

<p>The graph shows the proportion (Y axis) of each of the four genetic groups described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067010#pone-0067010-t003" target="_blank"><b>Table 3</b></a> in each of the 48 libraries, (X axis) ranked according to epidemiological week of the latest individual in the pool. Thus, the earliest cases are seen in the left, whereas the later cases are shown at right. The red dots represent the haplotypes of group IVb, i.e. those haplotypes that contained additional non-synonymous mutations to D248N. Black arrows in the top represent libraries in which individual amplicons were validated by Sanger sequencing. The asterisk (*) indicates those libraries which included an individual from the first wave.</p