Helena Baldez Vasconcelos

Zika virus in the Americas: Early epidemiological and genetic findings

Zika virus genomes from Brazil The Zika virus outbreak is a major cause for concern in Brazil, where it has been linked with increased reports of otherwise rare birth defects and neuropathology. In a phylogenetic analysis, Faria et al. infer a single introduction of Zika to the Americas and estimated the introduction date to be about May to December 2013—some 12 months earlier than the virus was reported. This timing correlates with major events in the Brazilian cultural calendar associated with increased traveler numbers from areas where Zika virus has been circulating. A correlation was also observed between incidences of microcephaly and week 17 of pregnancy. Science, this issue p. 345 Virus sequencing indicates that Zika arrived in Brazil during the middle of 2013, coincident with a surge in air travelers. Brazil has experienced an unprecedented epidemic of Zika virus (ZIKV), with ~30,000 cases reported to date. ZIKV was first detected in Brazil in May 2015, and cases of microcephaly potentially associated with ZIKV infection were identified in November 2015. We performed next-generation sequencing to generate seven Brazilian ZIKV genomes sampled from four self-limited cases, one blood donor, one fatal adult case, and one newborn with microcephaly and congenital malformations. Results of phylogenetic and molecular clock analyses show a single introduction of ZIKV into the Americas, which we estimated to have occurred between May and December 2013, more than 12 months before the detection of ZIKV in Brazil. The estimated date of origin coincides with an increase in air passengers to Brazil from ZIKV-endemic areas, as well as with reported outbreaks in the Pacific Islands. ZIKV genomes from Brazil are phylogenetically interspersed with those from other South American and Caribbean countries. Mapping mutations onto existing structural models revealed the context of viral amino acid changes present in the outbreak lineage; however, no shared amino acid changes were found among the three currently available virus genomes from microcephaly cases. Municipality-level incidence data indicate that reports of suspected microcephaly in Brazil best correlate with ZIKV incidence around week 17 of pregnancy, although this correlation does not demonstrate causation. Our genetic description and analysis of ZIKV isolates in Brazil provide a baseline for future studies of the evolution and molecular epidemiology of this emerging virus in the Americas.

Isolations of yellow fever virus from Haemagogus leucocelaenus in Rio Grande do Sul State, Brazil

Following howling monkey (Alouatta caraya) deaths and yellow fever (YF) antigen detection by immunohistochemistry in the liver sample of a dead monkey in April and May 2001 in the municipalities of Garruchos and Santo Antônio das Missões, Rio Grande do Sul State, Brazil, epidemiological field investigations were initiated. Two strains of YF virus were isolated in suckling mice from 23 Haemagogus (Conopostegus) leucocelaenus Dyar & Shannon mosquitoes collected from the study sites. The YF virus was isolated from this species in the 1930s in Brazil and in the 1940s in Colombia. No human cases were reported during the current epizootic outbreak. The YF virus isolation and the absence of Hg. (Haemagogus) janthinomys Dyar from the area suggest that Hg. leucocelaenus may be a secondary YF vector and play an important role in the epidemiology of this disease in the Southern Cone.

Phylogeography of dengue virus serotype 4, Brazil, 2010-2011.

Multiple origins indicate this serotype was introduced in several episodes.

Oropouche fever epidemic in Northern Brazil: epidemiology and molecular characterization of isolates.

BACKGROUND Oropouche fever virus is an important arbovirus associated with febrile disease that re-emerged in 2006 in several municipalities of Pará State, Bragantina region, Amazon, Brazil, 26 years after the last epidemic. OBJECTIVE To investigate an Oropouche fever outbreak in this region. STUDY DESIGN A serologic survey and prospective study of acute febrile cases were performed in Magalhães Barata (urban and rural areas) and Maracanã (rural area) municipalities. Serology (IgM-ELISA and hemagglutination-inhibition [HI]), virus isolation, RT-PCR and real-time-PCR were used to confirm Oropouche virus (OROV) as responsible for the febrile outbreaks. RESULTS Real-time-PCR showed high titers of OROV in acute-phase serum samples from febrile patients. From 113 of 119 acutely febrile patients with paired serum samples, OROV infections was confirmed by serologic conversion (n=76) or high titers (n=37) for both HI and IgM-ELISA. Patients had a febrile disease characterized by headache, chills, dizziness, photophobia, myalgia, nausea, and vomiting. Females and children under 15 years of age were most affected. Nucleotide sequencing of six OROV isolates identified that genotype II was associated with the human disease epidemic. CONCLUSIONS Oropouche fever, which has re-emerged in the Bragantina region in eastern Amazon 26 years after the last epidemic, is caused by genotype II, a lineage previously found only in Peru and western Brazil.

Molecular epidemiology of Oropouche virus, Brazil.

Oropouche virus (OROV) is the causative agent of Oropouche fever, an urban febrile arboviral disease widespread in South America, with >30 epidemics reported in Brazil and other Latin American countries during 1960–2009. To describe the molecular epidemiology of OROV, we analyzed the entire N gene sequences (small RNA) of 66 strains and 35 partial Gn (medium RNA) and large RNA gene sequences. Distinct patterns of OROV strain clustered according to N, Gn, and large gene sequences, which suggests that each RNA segment had a different evolutionary history and that the classification in genotypes must consider the genetic information for all genetic segments. Finally, time-scale analysis based on the N gene showed that OROV emerged in Brazil ≈223 years ago and that genotype I (based on N gene data) was responsible for the emergence of all other genotypes and for virus dispersal.

Reemergence of Oropouche fever, northern Brazil.

Oropouche fever has reemerged in Parauapebas and Porto de Moz municipalities, Pará State, Brazil. Serologic analysis (immunoglobulin M–ELISA) and virus isolation confirmed Oropouche virus (OROV) in both municipalities. Nucleotide sequencing of 2 OROV isolates from each location indicated genotypes I (Parauapebas) and II (Porto de Moz) in Brazil.

Full-length sequencing and genetic characterization of Breu Branco virus (Reoviridae, Orbivirus) and two related strains isolated from Anopheles mosquitoes.

Breu Branco virus (BE AR 492347) was isolated from Anopheles (Nyssorhynchus) triannulatus mosquitoes captured in Tucuruí, Pará State, northern Brazil, in 1988. No cross-reactivity by complement-fixation tests was observed between Breu Branco virus and other known arboviruses. Results of electron microscopy and physicochemical tests suggested that Breu Branco virus may be a member of the family Reoviridae. In order to elucidate its taxonomic status, a comprehensive genetic characterization was conducted for Breu Branco virus and related strains (BE AR 494475 and BE AR 486204) that were also isolated from Anopheles mosquitoes in the same area. This included full-length genome sequencing, determination of genetic traits and phylogenetic analysis. Breu Branco virus showed a similar genome organization to members of the genus Orbivirus, family Reoviridae. Genetically, Breu Branco virus was indistinguishable from strains BE AR 494475 and BE AR 486204. Phylogenetic analysis suggested that Breu Branco virus BE AR 492347 and its related strains constitute a novel species of the genus Orbivirus. Breu Branco virus is the first Brazilian orbivirus and the fifth orbivirus in the world to be sequenced fully.

Molecular epidemiology of dengue virus serotypes 2 and 3 isolated in Brazil from 1991 to 2008

The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.

Epidemiologia molecular dos sorotipos 2 e 3 do vírus dengue, isolados no Brasil de 1991 a 2008

The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.

Epidemiología molecular de los serotipos 2 y 3 del virus dengue, aislados en Brasil de 1991 a 2008

The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.The dengue virus (DENV1-4) causes dengue fever and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) in tropical and subtropical areas. The aim of this study was to evaluate the circulating genotypes of DENV. This was accomplished by sequencing the PrM and E genes of Brazilian isolates of DENV2 and DENV3 that were obtained between 1991 and 2008 from various geographic regions. Phylogenetic analyses of DENV2 demonstrated that the genotype III (Southeast Asian/American), in spite of several nucleotide and amino acid changes, was the only one that circulated over the past 19 years. Since its introduction in 2000, the DENV3 isolates that have been analyzed have all grouped into genotype III (Indian subcontinent) and there has been no evidence of DENV3 belonging to other genotypes in this study.