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Vasconcelos HB, Azevedo RSS, Casseb SM, Nunes-Neto JP, Chiang JO, Cantuária PC, Segura MNO, Martins LC, Monteiro HAO, Rodrigues SG, Nunes MRT, Vasconcelos PFC. Oropouche fever epidemic in Northern Brazil: epidemiology and molecular characterization of isolates. J Clin Virol 2008; 44:129-33. [PMID: 19117799 DOI: 10.1016/j.jcv.2008.11.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 11/13/2008] [Accepted: 11/15/2008] [Indexed: 10/21/2022]
Abstract
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.
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da Silva-Nunes M, de Souza VAF, Pannuti CS, Sperança MA, Terzian ACB, Nogueira ML, Yamamura AMY, Freire MS, da Silva NS, Malafronte RS, Muniz PT, Vasconcelos HB, da Silva EVP, Vasconcelos PFC, Ferreira MU. Risk factors for dengue virus infection in rural Amazonia: population-based cross-sectional surveys. Am J Trop Med Hyg 2008; 79:485-494. [PMID: 18840734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
A comparison of dengue virus (DENV) antibody levels in paired serum samples collected from predominantly DENV-naive residents in an agricultural settlement in Brazilian Amazonia (baseline seroprevalence, 18.3%) showed a seroconversion rate of 3.67 episodes/100 person-years at risk during 12 months of follow-up. Multivariate analysis identified male sex, poverty, and migration from extra-Amazonian states as significant predictors of baseline DENV seropositivity, whereas male sex, a history of clinical diagnosis of dengue fever, and travel to an urban area predicted subsequent seroconversion. The laboratory surveillance of acute febrile illnesses implemented at the study site and in a nearby town between 2004 and 2006 confirmed 11 DENV infections among 102 episodes studied with DENV IgM detection, reverse transcriptase-polymerase chain reaction, and virus isolation; DENV-3 was isolated. Because DENV exposure is associated with migration or travel, personal protection measures when visiting high-risk urban areas may reduce the incidence of DENV infection in this rural population.
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da Silva-Nunes M, Muniz PT, Freire MS, da Silva EVP, Malafronte RS, da Silva NS, Vasconcelos HB, Pannuti CS, Ferreira MU, Vasconcelos PFC, Terzian ACB, de Souza VAF, Sperança MA, Yamamura AMY, Nogueira ML. Risk Factors for Dengue Virus Infection in Rural Amazonia: Population-based Cross-sectional Surveys. Am J Trop Med Hyg 2008. [DOI: 10.4269/ajtmh.2008.79.485] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Blanton RE, Silva LK, Morato VG, Parrado AR, Dias JP, Melo PRS, Reis EAG, Goddard KAB, Nunes MRT, Rodrigues SG, Vasconcelos PFC, Castro JM, Reis MG, Barreto ML, Teixeira MG. Genetic ancestry and income are associated with dengue hemorrhagic fever in a highly admixed population. Eur J Hum Genet 2008; 16:762-5. [DOI: 10.1038/ejhg.2008.4] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Medeiros DBA, Nunes MRT, Vasconcelos PFC, Chang GJJ, Kuno G. Complete genome characterization of Rocio virus (Flavivirus: Flaviviridae), a Brazilian flavivirus isolated from a fatal case of encephalitis during an epidemic in São Paulo state. J Gen Virol 2007; 88:2237-2246. [PMID: 17622628 DOI: 10.1099/vir.0.82883-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The flaviviruses of major medical importance in South American countries are yellow fever, dengue, Saint Louis encephalitis, West Nile and Rocio viruses. Rocio virus (ROCV) has been responsible for epidemics of severe encephalitis in Brazil with a case-fatality rate of 10 % and development of sequelae in 20 % of the survivors. We have sequenced and characterized the entire genome of ROCV for the first time, by determining the general traits of the open reading frame and the characteristics of viral genes including the potential cleavage sites, conserved or unique motifs, cysteine residues and potential glycosylation sites. The conserved sequences in the 3′-non-coding region were identified, and the predicted secondary structures during cyclization between 5′- and 3′-non-coding regions were studied. Multiple protein and phylogenetic analyses based on antigenically important and phylogenetically informative genes confirmed a close relationship between ROCV and Ilheus virus (ILHV), together constituting a unique and distinct phylogenetic subgroup as well as the genetic relationship of ROCV with several members of the Japanese encephalitis group. Although ROCV is phylogenetically related to ILHV, our study shows that it is still a virus distinct from the latter virus. This is the first flavivirus uniquely indigenous to Brazil that has been sequenced completely and the genome characterized. The data should be useful for further studies at the molecular level, including construction of infectious clone, identification of gene function, improved disease surveillance based on molecular diagnostic tools and vaccine development.
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Martins LC, Diniz JAP, Silva EVP, Barros VLRS, Monteiro HAO, Azevedo RSS, Quaresma JAS, Vasconcelos PFC. Characterization of Minaçu virus (Reoviridae: Orbivirus) and pathological changes in experimentally infected newborn mice. Int J Exp Pathol 2007; 88:63-73. [PMID: 17244340 PMCID: PMC2517288 DOI: 10.1111/j.1365-2613.2006.00516.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Minaçu virus was isolated from Ochlerotatus scapularis (Diptera: Culicidae) in Minaçu, Goiás State, Brazil, in 1996. In attempting characterization of virus serological (hemagluttination inhibition, HI; indirect immunofluorescence assay, IFA), physicochemical [test for deoxycholate acid (DCA) sensitivity; polyacrylamide gel electrophoresis (PAGE)] tests and ultrastructural studies were made. Virus was also assayed in suckling mice after intracerebral inoculation of 0.02 ml and in VERO and C6/36 cells with 0.1 ml of viral suspension containing 10(5) LD50/ml. Inoculated and control systems were observed daily. Every 24 h, one control and two inoculated animals were killed for tissue testing, including histopathological changes by haematoxylin and eosin (HE)-stained sections, which were semi-quantified. Research into viral antigen in the tissues of mice [central nervous system (CNS), liver, heart, lungs, spleen and kidneys] was carried out by the immunohistochemical technique using the peroxidase system. The virus only replicated in VERO cells, with antigen positive by IFA. Positive complement fixation tests were only obtained using antiserum of Minaçu virus. Minaçu virus is DCA resistant; haemagglutinating activity was negative. By electronic microscopy non-enveloped virus particles were 75 nm in diameter. PAGE analysis showed Minaçu virus genome profile with 10 RNA segments. Infected, non-killed animals died 7 days after inoculation. Tissue lesions were observed in all organs, except the lungs. Intense lesions were observed in the CNS and the heart, where neurone and cardiocyte necroses, respectively, were noted. The liver, spleen and kidneys had moderate tissue changes. Viral antigens were more abundant in the CNS and the heart, and absent in the lungs. In conclusion, Minaçu virus belongs to the family Reoviridae, genus Orbivirus.
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Quaresma JAS, Barros VLRS, Pagliari C, Fernandes ER, Andrade HF, Vasconcelos PFC, Duarte MIS. Hepatocyte lesions and cellular immune response in yellow fever infection. Trans R Soc Trop Med Hyg 2007; 101:161-8. [PMID: 16872652 DOI: 10.1016/j.trstmh.2006.02.019] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 02/23/2006] [Accepted: 02/24/2006] [Indexed: 11/16/2022] Open
Abstract
The study of the in-situ cellular immune response is very important for the understanding of different liver infections. In the present study, 53 liver samples obtained by viscerotomy from patients who died during the course of jungle yellow fever were analyzed. The diagnosis was confirmed by serology, viral isolation and virus-specific immunohistochemistry. The specimens were analyzed by immunohistochemistry using specific antibodies for apoptosis, CD45RO, CD4, CD8, CD20, S100, CD57 and CD68. Quantitative analysis of the labeling pattern showed a clear predominance of the different phenotypes in the portal tract and midzone region of the acini. There was a predominance of T CD4+ lymphocytes, accompanied by the presence of T CD8+ lymphocytes, natural killer cells (CD57), macrophages and antigen-presenting cells (S100). The disproportion between the intensity of inflammation and the degree of hepatic injury was probably due to the intense apoptotic component, which classically does not induce an inflammatory response. The present study demonstrates that, despite the disproportion between injury and inflammation, the cellular immune response plays an important role in the pathogenesis of the hepatocytic injury observed in yellow fever, probably as a result of cytolytic actions through mechanisms involving MHC II and the activation of Fas receptors and granzymes/perforins.
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Aquino VH, Anatriello E, Gonçalves PF, DA Silva EV, Vasconcelos PFC, Vieira DS, Batista WC, Bobadilla ML, Vazquez C, Moran M, Figueiredo LTM. Molecular epidemiology of dengue type 3 virus in Brazil and Paraguay, 2002-2004. Am J Trop Med Hyg 2006; 75:710-5. [PMID: 17038699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
We studied the molecular epidemiology of dengue virus type 3 (DENV-3) in Brazil and Paraguay by analyzing the 5' and 3' untranslated regions (5' and 3'UTRs) and the E protein gene of viruses isolated between 2002 and 2004. Both 5' and 3'UTRs were highly conserved. However, the 3'UTR of two isolates from Brazil contained eight nucleotide deletions compared with the remaining 26 viruses. Phylogenetic analyses suggested that DENV-3 was introduced into Brazil from the Caribbean Islands at least twice and into Paraguay from Brazil at least three times.
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Diniz JAP, Da Rosa APAT, Guzman H, Xu F, Xiao SY, Popov VL, Vasconcelos PFC, Tesh RB. West Nile virus infection of primary mouse neuronal and neuroglial cells: the role of astrocytes in chronic infection. Am J Trop Med Hyg 2006; 75:691-6. [PMID: 17038696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
Primary cultures of embryonic murine neurons and newborn mouse astrocytes were inoculated with West Nile virus (WNV) strain NY385-99 to compare the pathogenesis of WNV infection in these types of CNS cells. Two different outcomes were observed. WNV infection in the neurons was rapidly progressive and destructive; within 5 days, all of the neurons were destroyed through apoptosis. WNV infection in the astrocytes evolved more slowly and did not seem to be highly lethal to the cells. The infected astrocytes continued to produce infectious virus (10(4.6)-10(6.5) PFU/mL) for 114 days, in a permissive, persistent infection. During this period, WNV antigen could be shown in the cytoplasm of the infected astrocytes by immunocytochemical assay, transmission electron microscopy of ultrathin sections, and in the cell culture medium by complement fixation test. Our results with this in vitro experimental murine cell model indicate that astrocytes can develop chronic or persistent infection with WNV, suggesting that these cells may play a role in the maintenance of WNV in the CNS.
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Powers AM, Aguilar PV, Chandler LJ, Brault AC, Meakins TA, Watts D, Russell KL, Olson J, Vasconcelos PFC, Da Rosa AT, Weaver SC, Tesh RB. Genetic relationships among Mayaro and Una viruses suggest distinct patterns of transmission. Am J Trop Med Hyg 2006; 75:461-9. [PMID: 16968922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Mayaro and Una viruses (MAYV, UNAV) are mosquito-borne alphaviruses that may cause an acute febrile illness characterized by headache, retro-orbital pain, and rash that may progress to a severe and prolonged arthralgia. MAYV was first isolated in Trinidad in 1954, and UNAV was first identified in northern Brazil in 1959. Since then, numerous isolates of these agents have been made from humans, wild vertebrates, and mosquitoes in several countries in northern South America. Serological evidence suggests that these viruses are also present in portions of Central America. Because little is known about the natural transmission cycle of MAYV and virtually nothing is known about UNAV transmission, 63 isolates covering the known geographic and temporal ranges were used in phylogenetic analyses to aid in understanding the molecular epidemiology. Approximately 2 kb from the E1 and E2 glycoprotein genes and the complete 3' non-coding region were sequenced. Phylogenetic analyses of these sequences indicated that two distinct genotypes of MAYV exist with a distinct clade consisting exclusively of UNAV (previously designated as a subtype of MAYV). One MAYV genotype (genotype D) contains isolates from Trinidad and the northcentral portion of South America including Peru, French Guiana, Surinam, Brazil, and Bolivia. All of these isolates are highly conserved with a nucleotide divergence of < 6%. The second MAYV genotype (genotype L) contains isolates only from Brazil that are highly conserved (< 4% nucleotide divergence) but are quite distinct (15-19%) from the first genotype isolates. These analyses provide possible explanations for the natural ecology and transmission of MAYV and UNAV.
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Diniz JAP, Nunes MRT, Travassos da Rosa APA, Cruz ACR, de Souza W, Medeiros DBA, Chiang JO, Vasconcelos PFC. Characterization of two new rhabdoviruses isolated from midges (Culicoides SPP) in the Brazilian Amazon: proposed members of a new genus, Bracorhabdovirus. Arch Virol 2006; 151:2519-27. [PMID: 16835701 DOI: 10.1007/s00705-006-0812-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Accepted: 06/01/2006] [Indexed: 11/24/2022]
Abstract
Itacaiunas and Curionopolis viruses were isolated from Culicoides midges in Parauapebas municipality, Pará state, Brazil, in 1984 and 1985, respectively. Itacaiunas virus infected newborn mice and mosquito cells (C6/36), but did not replicate in some mammalian cell lineages; while Curionopolis virus infected only mice. Neither virus showed a serological relationship with any of the 195 known arboviruses circulating in Brazil, nor against 38 other rhabdoviruses isolated worldwide. Both virus particles are bullet-shaped and similar in morphology to that observed for other members of the family Rhabdoviridae. Partial nucleotide sequencing of the N protein showed that those two viruses constitute a separate clade in the family Rhabdoviridae, which we propose to be a new genus, designated Bracorhabdovirus.
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Engel AR, Vasconcelos PFC, McArthur MA, Barrett ADT. Characterization of a viscerotropic yellow fever vaccine variant from a patient in Brazil. Vaccine 2006; 24:2803-9. [PMID: 16464518 DOI: 10.1016/j.vaccine.2006.01.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2005] [Revised: 12/28/2005] [Accepted: 01/02/2006] [Indexed: 11/16/2022]
Abstract
Although the live attenuated yellow fever (YF) 17D vaccine is considered to be one of the safest vaccines in the world today, several cases of disease associated with administration of the vaccine have been reported, including YF vaccine-associated viscerotropic disease (YF-VAVD), which was first described in 1996. All YF-VAVD isolates sequenced to date have shown very little genomic change when compared to their parental vaccine strains. In this study, we report the characterization of an isolate, BeH291597 (Brazil75), from a 1975 fatal case of YF-VAVD in Brazil. Comparison of Brazil75 with the genomic sequence of the parental 17DD vaccine strain revealed two amino acid substitutions (at positions M-49 and NS4B-240) that were unique to Brazil75. Although still a rare occurrence, this isolate suggests that YF-VAVD has been present much longer than previously recognized.
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Gomes-Leal W, Martins LC, Diniz JAP, Dos Santos ZA, Borges JA, Macedo CAC, Medeiros AC, De Paula LS, Guimarães JS, Freire MAM, Vasconcelos PFC, Picanço-Diniz CW. Neurotropism and neuropathological effects of selected rhabdoviruses on intranasally-infected newborn mice. Acta Trop 2006; 97:126-39. [PMID: 16266676 DOI: 10.1016/j.actatropica.2005.09.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 08/22/2005] [Accepted: 09/22/2005] [Indexed: 02/03/2023]
Abstract
Viral neurotropism is the ability of viruses to infect neuronal cells. This is well studied for herpesviruses, rabies-related viruses, and a few others, but it is poorly investigated among almost all arboviruses. In this study, we describe both the neurotropism and the neuropathological effects of Amazonian rhabdoviruses on the brains of experimentally infected-newborn mice. Suckling mice were intranasally infected with 10(-4) to 10(-8) LD50 of viruses. Animals were anaesthetized and perfused after they had become sick. Immunohistochemistry using specific anti-virus and anti-active caspase three antibodies was performed. All infected animals developed fatal encephalitis. Survival time ranged from 18 h to 15 days. Viruses presented distinct species-dependent neurotropism for CNS regions. Histopathological analysis revealed variable degrees of necrosis and apoptosis in different brain regions. These results showed that viruses belonging to the Rhabdoviridae family possess distinct tropism for CNS structures and induce different pattern of cell death depending on the CNS region.
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Quaresma JAS, Barros VLRS, Pagliari C, Fernandes ER, Guedes F, Takakura CFH, Andrade HF, Vasconcelos PFC, Duarte MIS. Revisiting the liver in human yellow fever: Virus-induced apoptosis in hepatocytes associated with TGF-β, TNF-α and NK cells activity. Virology 2006; 345:22-30. [PMID: 16278000 DOI: 10.1016/j.virol.2005.09.058] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Revised: 08/22/2005] [Accepted: 09/21/2005] [Indexed: 10/25/2022]
Abstract
Flavivirus infection as dengue and yellow fever persists as a terrible menace to pandemics, due to Aedes prevalence in the Americas. Yellow fever is characterized by hepatocyte damage, with steatosis, apoptosis and necrosis, mainly in the midzonal region of the liver, but the injury mechanism has not been studied at the light of recent knowledge, such as the advances in cell death mechanisms, inflammatory response and cytokine cell expression tools. We studied 53 human liver paraffin embedded blocks from patients who died with yellow fever, all with histological demonstration of higher prevalence of apoptosis over necrosis and mild disproportionate inflammatory response. Viral antigens were found most frequently in hepatocytes from the midzonal area than other lobule areas, as detected by specific immunohistochemistry. Infiltrating cell subpopulations showed mainly CD4+ T lymphocytes, with small numbers of CD8+ cytotoxic lymphocytes, CD20+ B lymphocytes, NKT+ cells and S100+ dendritic cells in the sites of inflammation, as compared to normal and leptospirosis liver blocks. Some cells expressed TNF-alpha and IFN-gamma, but a much more intense proportion of TGF-beta expressing cells were found, suggesting both a Th1 and Th3 patterns of immune response in yellow fever. Most affected hepatocyte presented apoptosis markers that appear at the cell death main pathway in this infection. Viral antigens, which production could interfere in hepatocyte biology, could induce the activation of apoptosis cascade, but TGF-beta was also an apoptosis promoter. Our finding supports the key effect of the yellow fever virus in hepatocyte injury, resulting in prevalence of apoptosis over necrosis, aside from a TGF-beta action induced by the inflammatory response.
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Quaresma JAS, Duarte MIS, Vasconcelos PFC. Midzonal lesions in yellow fever: A specific pattern of liver injury caused by direct virus action and in situ inflammatory response. Med Hypotheses 2006; 67:618-21. [PMID: 16650626 DOI: 10.1016/j.mehy.2006.01.060] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2005] [Revised: 01/08/2006] [Accepted: 01/10/2006] [Indexed: 01/12/2023]
Abstract
Yellow fever is an acute infectious, non-contagious disease characterized by intense vasculopathy and lesions in different organs. In the liver, one of the main targets of the virus, the infection induces a characteristic midzonal injury characterized by hepatocyte necrosis, apoptosis and steatosis. This characteristics pattern of liver injury in yellow fever is also observed in conditions of low-flow hypoxia and other infections such as dengue and Rift Valley fever. There are no reports in the literature explaining the genesis of this peculiar histopathological pattern in yellow fever. Some hypotheses have been proposed to explain the mechanism of this midzonal distribution pattern observed in the liver such as low-flow hypoxia and tropism of the virus toward hepatocytes in this area. These hypotheses are discussed in view of more recent findings regarding the pathogenesis of yellow fever and regarding hepatic physiopathology, and a new hypothesis is proposed: the midzonal necrosis is consequence of action of combined factors mainly the direct cytopathic effect of YFV associated with a potent immune response in which CD4+ and CD8+ lymphocytes and the cytokines, especially TGF-beta, but also TNF-alpha and IFN-gamma play an important role.
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Da Silva EVP, Da Rosa APAT, Nunes MRT, Diniz JAP, Tesh RB, Cruz ACR, Vieira CMA, Vasconcelos PFC. Araguari virus, a new member of the family Orthomyxoviridae: serologic, ultrastructural, and molecular characterization. Am J Trop Med Hyg 2005; 73:1050-8. [PMID: 16354811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
This paper reports the results of serologic, structural, biochemical, and genetic studies indicating that Araguari virus, a previously unassigned viral agent, is a member of the family Orthomyxoviridae and genus Thogotovirus. Araguari virus has six RNA fragments; biologically, it shares several properties with other viruses in the family Orthomyxoviridae. Nucleotide sequencing of the RNA segments 4 (glycoprotein) and 5 (nucleoprotein) of Araguari virus aligned with the orthomyxoviruses, showing the closest relationship with Thogoto virus (sequence similarity = 61.9% and 69.1%, respectively, for glycoprotein and nucleoprotein), but also sharing a more distant similarity with Dhori and Influenza C viruses, especially for the glycoprotein gene. Based on these results, we propose that Araguari virus should be assigned as a new member of the family Orthomyxoviridae and genus Thogotovirus.
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Pinheiro VCS, Tadei WP, Barros PMSS, Vasconcelos PFC, Cruz ACR. Detection of dengue virus serotype 3 by reverse transcription-polymerase chain reaction in Aedes aegypti (Diptera, Culicidae) captured in Manaus, Amazonas. Mem Inst Oswaldo Cruz 2005; 100:833-9. [PMID: 16444413 DOI: 10.1590/s0074-02762005000800003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The detection of dengue virus serotypes from Aedes aegypti in Manaus, state of Amazonas was carried out using the reverse transcription-polymerase chain reaction technique. Fourteen pools out 82 (17.1%) were positive for DENV3, providing a minimal infection rate of 2.1% of all analyzed infected female specimens of three different areas of the city.
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Nunes MRT, Travassos da Rosa APA, Weaver SC, Tesh RB, Vasconcelos PFC. Molecular epidemiology of group C viruses (Bunyaviridae, Orthobunyavirus) isolated in the Americas. J Virol 2005; 79:10561-70. [PMID: 16051848 PMCID: PMC1182628 DOI: 10.1128/jvi.79.16.10561-10570.2005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To date, no molecular studies on group C viruses (Bunyaviridae, Orthobunyavirus) have been published. We determined the complete small RNA (SRNA) segment and partial medium RNA segment nucleotide sequences for 13 group C members. The full-length SRNA sequences ranged from 915 to 926 nucleotides in length, and revealed similar organization in comparison with other orthobunyaviruses. Based on the 705 nucleotides of the N gene, group C members were distributed into three major phylogenetic groups, with the exception of Madrid virus, which was placed outside of these three groups. Analysis of the Caraparu virus strain BeH 5546 revealed that it has an SRNA sequence nearly identical to that of Oriboca virus and is a natural reassortant virus. In addition, analysis of 345 nucleotides of the Gn gene for eight group C viruses and for strain BeH 5546 revealed a different phylogenetic topology, suggesting a reassortment pattern among them. These findings represent the first evidence for natural reassortment among the group C viruses, which include several human pathogens. Furthermore, our genetic data corroborate previous relationships determined using serologic assays (complement fixation, hemagglutination inhibition, and neutralization tests) and suggest that a combination of informative molecular, serological, and ecological data is a helpful tool to understand the molecular epidemiology of arboviruses.
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Bryant JE, Vasconcelos PFC, Rijnbrand RCA, Mutebi JP, Higgs S, Barrett ADT. Size heterogeneity in the 3' noncoding region of South American isolates of yellow fever virus. J Virol 2005; 79:3807-21. [PMID: 15731274 PMCID: PMC1075708 DOI: 10.1128/jvi.79.6.3807-3821.2005] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The 3' noncoding region (3' NCR) of flaviviruses contains secondary and tertiary structures essential for virus replication. Previous studies of yellow fever virus (YFV) and dengue virus have found that modifications to the 3' NCR are sometimes associated with attenuation in vertebrate and/or mosquito hosts. The 3' NCRs of 117 isolates of South American YFV have been examined, and major deletions and/or duplications of conserved RNA structures have been identified in several wild-type isolates. Nineteen isolates (designated YF-XL isolates) from Brazil, Trinidad, and Venezuela, dating from 1973 to 2001, exhibited a 216-nucleotide (nt) duplication, yielding a tandem repeat of conserved hairpin, stem-loop, dumbbell, and pseudoknot structures. YF-XL isolates were found exclusively within one subclade of South American genotype I YFV. One Brazilian isolate exhibited, in addition to the 216-nt duplication, a deletion of a 40-nt repeated hairpin (RYF) motif (YF-XL-DeltaRYF). To investigate the biological significance of these 3' NCR rearrangements, YF-XL-DeltaRYF and YF-XL isolates, as well as other South American YFV isolates, were evaluated for three phenotypes: growth kinetics in cell culture, neuroinvasiveness in suckling mice, and ability to replicate and produce disseminated infections in Aedes aegypti mosquitoes. YF-XL-DeltaRYF and YF-XL isolates showed growth kinetics and neuroinvasive characteristics comparable to those of typical South American YFV isolates, and mosquito infectivity trials demonstrated that both types of 3' NCR variants were capable of replication and dissemination in a laboratory-adapted colony of A. aegypti.
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Rosa EST, Mills JN, Padula PJ, Elkhoury MR, Ksiazek TG, Mendes WS, Santos ED, Araújo GCB, Martinez VP, Rosa JFST, Edelstein A, Vasconcelos PFC. Newly Recognized Hantaviruses Associated with Hantavirus Pulmonary Syndrome in Northern Brazil: Partial Genetic Characterization of Viruses and Serologic Implication of Likely Reservoirs. Vector Borne Zoonotic Dis 2005; 5:11-9. [PMID: 15815145 DOI: 10.1089/vbz.2005.5.11] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Following the occurrence of the first laboratory-confirmed cases of hantavirus pulmonary syndrome (HPS) in Maranhao State, Brazil, rodents were trapped and rodent materials screened by ELISA for antibodies to Sin Nombre and Andes hantaviruses. Antibody-positive samples were tested by RT-PCR, amplified products were sequenced, and phylogenetic trees were constructed for comparison with known hantaviruses. From 104 rodent blood samples collected (40 Bolomys lasiurus, 52 Holochilus sciureus, 12 Oligoryzomys fornesi, and one Proechimys guyannensis), 21 (20.2%) were antibody-positive (one B. lasiurus, five O. fornesi, and 15 H. sciureus). Hantavirus RNA was amplified by PCR from two O. fornesi and four H. sciureus. Viral sequencing identified two hantavirus genotypes. The genotype recovered from O. fornesi, is designated herein as Anajatuba (ANAJ) and the genotype recovered from H. sciureus is designated Rio Mearim (RIME). Phylogenetic analysis of a 643-nucleotide region of the N segment showed both viruses to be most closely related (94-96% nucleotide homology) to Río Mamoré virus, a virus associated with Oligoryzomys microtis in Bolivia and Peru, but not found in northern Brazil. O. fornesi was frequently captured in and around human dwellings. H. sciureus, is a semi-aquatic rodent captured only in remote areas rarely frequented by humans.
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71
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Vasconcelos PFC, Bryant JE, da Rosa TPA, Tesh RB, Rodrigues SG, Barrett ADT. Genetic divergence and dispersal of yellow fever virus, Brazil. Emerg Infect Dis 2004; 10:1578-84. [PMID: 15498159 PMCID: PMC3320275 DOI: 10.3201/eid1009.040197] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Examining viral isolates collected over 66 years shows divergence into clades and potential dispersal by human migration. An analysis of 79 yellow fever virus (YFV) isolates collected from 1935 to 2001 in Brazil showed a single genotype (South America I) circulating in the country, with the exception of a single strain from Rondônia, which represented South America genotype II. Brazilian YFV strains have diverged into two clades; an older clade appears to have become extinct and another has become the dominant lineage in recent years. Pairwise nucleotide diversity between strains ranged from 0% to 7.4%, while amino acid divergence ranged from 0% to 4.6%. Phylogenetic analysis indicated traffic of virus variants through large geographic areas and suggested that migration of infected people may be an important mechanism of virus dispersal. Isolation of vaccine virus from a patient with a fatal case suggests that vaccine-related illness may have been misdiagnosed in the past.
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72
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Weidmann M, Rudaz V, Nunes MRT, Vasconcelos PFC, Hufert FT. Rapid detection of human pathogenic orthobunyaviruses. J Clin Microbiol 2003; 41:3299-305. [PMID: 12843078 PMCID: PMC165340 DOI: 10.1128/jcm.41.7.3299-3305.2003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Modern detection and identification tools can help to provide answers to urgent questions about the incidence, prevalence, and epidemiology of currently emerging diseases. We developed highly sensitive one-step TaqMan reverse transcription-PCR assays with sensitivities ranging from 10(4) to 10(1) molecules for 11 human pathogens of the orthobunyaviruses. We compared the performances of these assays on three currently available cyclers (ABI-PRISM 7700, LightCycler, and SmartCycler). The assay for Oropouche virus (OROV) was tested using sera collected from days 1 to 5 after onset of OROV disease and was found to be greatly superior to an established nested PCR system. A mean copy number of 1.31 x 10(7) OROV RNA/ml of serum was detected. Diagnostic RNA detection can be used as early as day 1 after onset of OROV disease. The use of a mobile SmartCycler and a hands-on time of less than 3 h could help to intensify outbreak surveillance and control, especially in field studies.
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73
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Degallier N, Teixeira JMSC, Soares Sd SDS, Pereira RD, Pinto SCF, Chaib Ad ADJM, Vasconcelos PFC, Oliveira E. Aedes albopictus may not be vector of dengue virus in human epidemics in Brazil. Rev Saude Publica 2003; 37:386-7. [PMID: 12792692 DOI: 10.1590/s0034-89102003000300019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Over 60,500 dengue cases were reported in the state of Espírito Santo (ES), Brazil, between 1995 and 1998. The study's purpose was to identify whether Aedes albopictus was transmitting the dengue virus during an epidemic in the locality of Vila Beth nia (Viana County),Vitória, ES. From April 3 to 9, 1998, blood and serum samples were collected daily for virus isolation and serological testing. Four autochthonous cases were confirmed through DEN 1 virus isolation and two autochthonous cases through MAC ELISA testing. Of 37 Ae. aegypti and 200 Ae. albopictus adult mosquitoes collected and inoculated, DEN1 virus was isolated only from a pool of two Ae. aegypti female mosquitoes. The study results suggest that Ae. albopictus still cannot be considered an inter-human vector in dengue epidemics in Brazil.
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74
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Vasconcelos PFC. Diagnosis of viral disease. Lancet 2003; 361:1589. [PMID: 12747877 DOI: 10.1016/s0140-6736(03)13307-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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75
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Mondet B, Vasconcelos PFC, Travassos da Rosa APA, Travassos da Rosa ES, Rodrigues SG, Travassos Rosa JFS, Bicout DJ. Isolation of yellow fever virus from nulliparous Haemagogus (Haemagogus) janthinomys in eastern Amazonia. Vector Borne Zoonotic Dis 2003; 2:47-50. [PMID: 12656130 DOI: 10.1089/153036602760260779] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In 1998, an epizootic of yellow fever (YF) killed many howler monkeys (Alouatta spp.) in eastern Amazonia near the city of Altamira. An infection level with YF virus of approximately 3.6% was determined from analysis of 456 females of Haemagogus janthinomys Dyar, the main enzootic YF vector in South America. One month later, a second study of 164 females captured in the same place led to infection levels of 0.8% for parous and 2.9% for nulliparous females. These results lead to the conclusion that vertical transmission, one of the key elements in the epidemiology of YF, occurs in South America as it does in Africa.
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76
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Teixeira MDG, Barreto ML, Costa MDCN, Ferreira LDA, Vasconcelos PFC, Cairncross S. Dynamics of dengue virus circulation: a silent epidemic in a complex urban area. Trop Med Int Health 2002; 7:757-62. [PMID: 12225506 DOI: 10.1046/j.1365-3156.2002.00930.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Serotypes of dengue DEN-1 and DEN-2 have been reported in much of Brazil over the last 15 years, and DEN-3 serotype was only recently detected. This prospective study was conducted in Salvador, a large city in north-east Brazil, where two epidemics were previously recorded (DEN-1 and DEN-2). We obtained the seroprevalence and 1-year incidence of dengue infections in the population of 30 sampling areas of Salvador and analysed the relationship between intensity of viral circulation, standard of living and vector density. High seroprevalence (68.7%) and annual incidence (70.6%) of infection for one or both circulating serotypes (DEN-1 and DEN-2) were found. High rates of transmission were observed in all studied areas, from the highest to the lowest socio-economic status. The mean PI (Premise Index) for Aedes aegypti was 7.4% (range 0.27-25.6%). Even in the areas with the lowest PI (</=3%) the observed seroincidence was 54.6%. These findings highlighted the existence of a silent epidemic during a period perceived by the Health Services as of low endemicity, indicating the strength and speed of dengue transmission in the city of Salvador.
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77
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Leão RNQ, Oikawa T, Rosa EST, Yamaki JT, Rodrigues SG, Vasconcelos HB, Sousa MRS, Tsukimata JK, Azevedo RSS, Vasconcelos PFC. Isolation of dengue 2 virus from a patient with central nervous system involvement (transverse myelitis). Rev Soc Bras Med Trop 2002; 35:401-4. [PMID: 12170337 DOI: 10.1590/s0037-86822002000400018] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A dengue fever case is described in a 58-year-old male patient with febrile illness and thrombocytopenia complicated by neurological involvement characterized by transverse myelitis followed by weakness of both legs and flaccid paralysis. Muscle strength was much diminished and bilateral areflexia was observed. Dengue 2 (DEN-2) virus was isolated and the patient sero-converted by hemagglutination-inhibition and IgM-ELISA tests. The RT-PCR test was positive to DEN-2 in acute phase serum and culture supernatant, but negative in the cerebrospinal fluid. After three weeks of hospitalization the patient was discharged. No other infectious agent was detected in the blood and cerebrospinal fluid samples. The patient had full recovery from paralysis six months after the onset of DEN-2 infection.
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78
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Wanzeller ALM, Diniz JAP, Gomes MLC, Cruz ACR, Soares MCP, de Souza W, Travassos da Rosa APA, Vasconcelos PFC. Ultrastructural, antigenic and physicochemical characterization of the Mojuí dos Campos (Bunyavirus) isolated from bat in the Brazilian Amazon region. Mem Inst Oswaldo Cruz 2002; 97:307-11. [PMID: 12048556 DOI: 10.1590/s0074-02762002000300005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Mojuí dos Campos virus (MDCV) was isolated from the blood of an unidentified bat (Chiroptera) captured in Mojuí dos Campos, Santarém, State of Pará, Brazil, in 1975 and considerated to be antigenically different from other 102 arboviruses belonging to several antigenic groups isolated in the Amazon region or another region by complement fixation tests. The objective of this work was to develop a morphologic, an antigenic and physicochemical characterization of this virus. MDCV produces cytopathic effect in Vero cells, 24 h post-infection (p.i), and the degree of cellular destruction increases after a few hours. Negative staining electron microscopy of the supernatant of Vero cell cultures showed the presence of coated viral particles with a diameter of around 98 nm. Ultrathin sections of Vero cells, and brain and liver of newborn mice infected with MDCV showed an assembly of the viral particles into the Golgi vesicles. The synthesis kinetics of the proteins for MDCV were similar to that observed for other bunyaviruses, and viral proteins could be detected as early as 6 h p.i. Our results reinforce the original studies which had classified MDCV in the family Bunyaviridae, genus Bunyavirus as an ungrouped virus, and it may represent the prototype of a new serogroup.
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79
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Silva HR, Tanajura GM, Tavares-Neto J, Gomes Md MDLC, Linhares Ad ADC, Vasconcelos PFC, Ko AI. [Aseptic meningitis syndrome due to enterovirus and Leptospira sp in children of Salvador, Bahia]. Rev Soc Bras Med Trop 2002; 35:159-65. [PMID: 12011925 DOI: 10.1590/s0037-86822002000200006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
For the purpose of identifying the frequency that enterovirus, leptospires, arbovirus cause aseptic meningitis syndrome (AMS) during non-epidemic periods and comparing patients with and without laboratory evidence for an etiologic agent, 112 patients were selected aged between 3 months and 15 years and a clinical suspicion of AMS and were referred to Couto Maia Hospital, the Infectious and Parasitic Disease Reference Center for Salvador, Bahia. In 44.6% (n=50), the etiologic agent for the diagnosis was laboratory-confirmed: enterovirus was identified in 37.7% (n=42) of the cases by the PCR Amplicor diagnostic kit, cerebrospinal fluid or fecal culture isolation; Leptospira sp. in 7.12% (n=8) by the microagglutination test; and arbovirus in non of the cases by inhibition of passive hemagglutination. In 14 of the 22 enteroviral isolates that were evaluated, 6 different serotypes were identified with Echovirus-4 being the major serotype (27.2%; 6/22) among all found (Coxsackie B2, B3, B6 and B9; Enterovirus 71). In conclusion, enteroviruses were the most frequent etiologic agent of AMS and that leptospirosis should be included in the differential diagnosis. In addition, patients with and without laboratory-confirmed identification of the etiologic agent had similar demographic and clinical characteristics and cerebrospinal fluid findings (p >0.05), therefore suggesting that patients without a confirmed diagnosis had enteroviral or leptospiral etiologies.
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Dégallier N, Travassos da Rosa APA, Vasconcelos PFC, Travassos da Rosa JFS, Travassos da Rosa ES, Rodrigues SG. Ecological aspects of arboviroses in Brazilian Amazonas, South America. VIRUS REVIEWS & RESEARCH 1996. [DOI: 10.17525/vrrjournal.v1i1-2.149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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