Cacipacore virus as an emergent mosquito-borne Flavivirus.

INTRODUCTION:: Cacipacore virus (CPCV), a possible bird-associated flavivirus, has yet to be detected in mosquitoes. Our purpose is examining CPCV in mosquitoes from the Amazon region of Brazil. METHODS:: Approximately 3,253 Culicidae (grouped into 264 pools) were collected from the Amazon region during 2002-2006 and analyzed using a Flavivirus genus-specific reverse transcription- polymerase chain reaction followed by nested polymerase chain reaction assay and by nucleotide sequencing of amplicons. RESULTS:: Nucleotide sequences from five mosquito samples showed high similarity to the those of CPCV originally isolated in the Amazon region. CONCLUSIONS:: This is the first report of CPCV-infected mosquitoes which has implications on the arbovirus maintenance in nature and transmission to man.

Cacipacore virus as an emergent mosquito-borne Flavivirus

Abstract INTRODUCTION: Cacipacore virus (CPCV), a possible bird-associated flavivirus, has yet to be detected in mosquitoes. Our purpose is examining CPCV in mosquitoes from the Amazon region of Brazil. METHODS: Approximately 3,253 Culicidae (grouped into 264 pools) were collected from the Amazon region during 2002-2006 and analyzed using a Flavivirus genus-specific reverse transcription- polymerase chain reaction followed by nested polymerase chain reaction assay and by nucleotide sequencing of amplicons. RESULTS: Nucleotide sequences from five mosquito samples showed high similarity to the those of CPCV originally isolated in the Amazon region. CONCLUSIONS: This is the first report of CPCV-infected mosquitoes which has implications on the arbovirus maintenance in nature and transmission to man.

Genetic characterization of Cacipacoré virus from ticks collected in São Paulo State, Brazil.

Cacipacoré virus (CPCV) is a potential emerging virus classified in the genus Flavivirus, family Flaviviridae. In the present study, we present the genetic characterization of a CPCV isolated from ticks (Amblyomma cajennense) collected from a sick capybara (Hydrochoerus hydrochaeris) in São Paulo State, Brazil. The CPCV isolate shares the typical genomic organization of flaviviruses with 10,857 nucleotides in length and a single open reading frame of 10,284 nucleotides encoding a polyprotein of 3,427 amino acids. Phylogenetic analysis revealed that CPCV is unique, as a potentially tick-borne virus, in the Japanese encephalitis virus serogroup.

Development and optimization of a sensitive TaqMan® real-time PCR with synthetic homologous extrinsic control for quantitation of Human cytomegalovirus viral load.

Human cytomegalovirus (Human herpesvirus 5, HCMV) causes frequent asymptomatic infections in the general population. However, in immunosuppressed patients or congenitally infected infants, HCMV is related to high morbidity and mortality. In such cases, a rapid viral detection is crucial for monitoring the clinical outcome and the antiviral treatment. In this study, we optimized a sensitive biplex TaqMan® real-time PCR for the simultaneous detection and differentiation of a partial HCMV UL97 sequence and homologous extrinsic control (HEC) in the same tube. HEC was represented by a plasmid containing a modified HCMV sequence retaining the original primer binding sites, while the probe sequence was substituted by a phylogenetically divergent one (chloroplast CF0 subunit plant gene). It was estimated that the optimal HEC concentration, which did not influence the HCMV amplification is 1,000 copies/reaction. The optimized TaqMan® PCR demonstrated high analytical sensitivity (6.97 copies/reaction, CI = 95%) and specificity (100%). Moreover, the reaction showed adequate precision (repeatability, CV = 0.03; reproducibility, CV = 0.0027) and robustness (no carry-over or cross-contamination). The diagnostic sensitivity (100%) and specificity (97.8%) were adequate for the clinical application of the molecular platform. The optimized TaqMan® real-time PCR is suitable for HCMV detection and quantitation in predisposed patients and monitoring of the applied antiviral therapy. J. Med. Virol. 88:1604-1612, 2016. © 2016 Wiley Periodicals, Inc.

Polymorphisms in human leukocyte antigens, human platelet antigens, and cytokine genes in hantavirus cardiopulmonary syndrome patients from Ribeirão Preto, Brazil.

Hantavirus cardiopulmonary syndrome is a severe human disease associated with hantavirus infection. The clinical course of illness varies greatly among individuals, possibly due to viral and immunological elements and the influence of host genetic factors on clinical outcome. As the magnitude of immune activation has been associated with disease severity, polymorphisms in genes involved in the immune response that may affect the development of this syndrome were investigated. Polymorphisms in the TGF-ß, IL-10, IL-6, and IFN-γ genes, human leukocyte antigens (HLA), and human platelet alloantigens (HPA) genes were investigated in 122 patients with Araraquara virus infection from Ribeirão Preto, Brazil. Patients were divided into two groups: hantavirus cardiopulmonary syndrome (HCPS group; n = 26) and hantavirus seropositive only (n = 96). The frequencies of HLA alleles, cytokines and platelet antigen genotypes were evaluated in both groups and compared to a control group. The data demonstrated no significant influence of the HLA alleles, HPA, IL-6, and IL-10 genotypes on susceptibility to hantavirus infection. However, the hantavirus seropositive group presented a significantly higher frequency of a polymorphism associated with a high IFN-γ production than the HCPS group. In addition, a genotype associated with high TGF-ß production was found more frequently in individuals infected with hantavirus than in the control group. This phenotype was associated with a less intense thrombocytopenia in the HCPS group and may be protective against the most severe form of hantavirus disease. More studies are required to quantify further the influence of the high TGF-ß producer phenotype on the outcome of hantavirus infection.

Serologic survey of hantavirus in a rural population from the northern State of Mato Grosso, Brazil

INTRODUCTION: Hantavirus is a genus of ribonucleic acid (RNA) viruses included in the family Bunyaviridae. Hantaviruses are rodent-borne zoonoses that, in the last 18 years, became an emergent public health problem in the Americas, causing a severe cardiopulmonary syndrome. This disease has no specific treatment and has a high case fatality. The transmission of hantavirus to man occurs by inhaling aerosols of rodent excreta. The aim of this study was to determine the prevalence of antibodies to hantavirus in the population of the rural settlement of Tupã in the county of Marcelândia, state of Mato Grosso, Brazil. METHODS: The participants of the serologic survey were visited at their homes and selected randomly among the settlement population. Blood samples of the participants were collected by venopuncture. The serum samples were tested by an IgG-ELISA using an N recombinant protein of Araraquara hantavirus as antigen, using the protocol previously established by Figueiredo et al. RESULTS: IgG antibodies to hantavirus were detected in 7 (13%) of the 54 participants. The positivity was higher among men. It was observed that there was an association of seropositivity to hantavirus within the participants born in the south of Brazil. CONCLUSIONS: The results suggest that, in this rural area, everyone is exposed to the same risk of becoming infected with hantavirus, and, therefore, there is a need to intensify surveillance activities and education of the local people to prevent this viral infection.

Serologic survey of hantavirus in a rural population from the northern State of Mato Grosso, Brazil.

INTRODUCTION: Hantavirus is a genus of ribonucleic acid (RNA) viruses included in the family Bunyaviridae. Hantaviruses are rodent-borne zoonoses that, in the last 18 years, became an emergent public health problem in the Americas, causing a severe cardiopulmonary syndrome. This disease has no specific treatment and has a high case fatality. The transmission of hantavirus to man occurs by inhaling aerosols of rodent excreta. The aim of this study was to determine the prevalence of antibodies to hantavirus in the population of the rural settlement of Tupã in the county of Marcelândia, state of Mato Grosso, Brazil. METHODS: The participants of the serologic survey were visited at their homes and selected randomly among the settlement population. Blood samples of the participants were collected by venopuncture. The serum samples were tested by an IgG-ELISA using an N recombinant protein of Araraquara hantavirus as antigen, using the protocol previously established by Figueiredo et al. RESULTS: IgG antibodies to hantavirus were detected in 7 (13%) of the 54 participants. The positivity was higher among men. It was observed that there was an association of seropositivity to hantavirus within the participants born in the south of Brazil. CONCLUSIONS: The results suggest that, in this rural area, everyone is exposed to the same risk of becoming infected with hantavirus, and, therefore, there is a need to intensify surveillance activities and education of the local people to prevent this viral infection.

A retrospective serologic survey of hantavirus infections in the county of Cássia dos Coqueiros, State of São Paulo, Brazil / Inquérito sorológico retrospectivo das infecções por hantavirus no município de Cássia dos Coqueiros, Estado de São Paulo, Brasil

INTRODUCTION: In recent years, hantavirus infections producing severe diseases have obtained an increased attention from public health authorities from the countries of Eurasia to the Americas. Brazil has reported 1,300 cases of hantavirus cardiopulmonary syndrome (HCPS) from 1993 to 2010, with about 80 of them occurring in the northeast of the State of São Paulo, with 48% fatality rate. Araraquara virus was the causative agent of HCPS in the region. Considering that hantaviruses causing human disease in the Americas were unknown until 1993, we have looked for hantavirus infections in the population of Cássia dos Coqueiros county, northeast of the State of São Paulo, Brazil, before this time. This county has about 2,800 inhabitants and an economy based on agriculture, including cultivation of Brachiaria decumbens grass. The grass seeds are an important rodent attraction, facilitating transmission of hantavirus to man. Four HCPS cases were reported so far in the county. METHODS: In this study, 1,876 sera collected from 1987 to 1990 were tested for IgG to hantavirus by IgG-ELISA, using the N recombinant protein of Araraquara virus as antigen. RESULTS: Positive results were observed in 89 (4.7%) samples, which were all collected in 1987. The positivity among urban inhabitants was 5.3%, compared with 4.3% among those living in rural areas. CONCLUSIONS: Our results showed that hantavirus infections occurred in Cássia dos Coqueiros, completely unrecognized, even before hantaviruses were described in the Americas.

INTRODUÇÃO: Infecções graves por hantavírus têm obtido crescente atenção das autoridades da saúde pública da Eurásia e Américas. De 1993 a 2010, o Brasil reportou 1.300 casos de síndrome pulmonar cardiovascular por hantavírus (SPCVH) com, aproximadamente, 80 deles no nordeste do Estado de São Paulo com taxa de fatalidade de 48%. O vírus Araraquara é o agente etiológico da SPCVH nessa região. Considerando que nas Américas as doenças em humanos causadas por hantavírus eram desconhecidas até 1993, procuramos infecções por hantavírus nas populações do município de Cássia dos Coqueiros, nordeste de São Paulo, Brasil, antes dessa data. Esse município tem 2.800 habitantes e economia baseada na agricultura, com intenso cultivo da gramínea Brachiaria decumbens. Sementes de gramíneas têm um papel importante em atrair roedores, facilitando a transmissão de hantavírus para humanos. Nesse município, até o momento 4 casos haviam sido reportados. MÉTODOS:Neste estudo, coletou-se 1.876 soros entre 1987 a 1990 e testamos para pesquisa de IgG contra hantavirus utilizando um ELISA que tem como antígeno a proteína N recombinante do vírus Araraquara. RESULTADOS: Dentre os soros analisados, 89 (4,7%) foram positivos, mostrando que esta infecção já ocorria previamente à descrição dos hantavirus americanos e deve estar ocorrendo há anos nesta região. A positividade entre os habitantes urbanos foi de 5,3% se comparado com 4,3% entre aqueles que viviam em áreas rurais. CONCLUSÕES: Nossos resultados mostraram que as infecções ocorridas por hantavirus foram completamente despercebidas em Cássia dos Coqueiros antes da descrição do hantavirus americano.

A retrospective serologic survey of hantavirus infections in the county of Cássia dos Coqueiros, State of São Paulo, Brazil.

INTRODUCTION: In recent years, hantavirus infections producing severe diseases have obtained an increased attention from public health authorities from the countries of Eurasia to the Americas. Brazil has reported 1,300 cases of hantavirus cardiopulmonary syndrome (HCPS) from 1993 to 2010, with about 80 of them occurring in the northeast of the State of São Paulo, with 48% fatality rate. Araraquara virus was the causative agent of HCPS in the region. Considering that hantaviruses causing human disease in the Americas were unknown until 1993, we have looked for hantavirus infections in the population of Cássia dos Coqueiros county, northeast of the State of São Paulo, Brazil, before this time. This county has about 2,800 inhabitants and an economy based on agriculture, including cultivation of Brachiaria decumbens grass. The grass seeds are an important rodent attraction, facilitating transmission of hantavirus to man. Four HCPS cases were reported so far in the county. METHODS: In this study, 1,876 sera collected from 1987 to 1990 were tested for IgG to hantavirus by IgG-ELISA, using the N recombinant protein of Araraquara virus as antigen. RESULTS: Positive results were observed in 89 (4.7%) samples, which were all collected in 1987. The positivity among urban inhabitants was 5.3%, compared with 4.3% among those living in rural areas. CONCLUSIONS: Our results showed that hantavirus infections occurred in Cássia dos Coqueiros, completely unrecognized, even before hantaviruses were described in the Americas.

Prevalence of serum antibodies to hantavirus in a rural population from the Southern State of Santa Catarina, Brazil.

INTRODUCTION: Rodent-borne hantaviruses cause severe human diseases. We completed a serological survey of hantavirus infection in rural inhabitants of Turvo County, in the southern State of Santa Catarina, Brazil, in which seropositivity for hantavirus was correlated to previous disease in the participants. METHODS: The levels of IgG antibodies to hantavirus Araraquara in the sera of 257 individuals were determined using an immunoenzymatic assay. RESULTS: IgG antibodies to hantavirus were found in 2.3% of the participants. All seropositive participants reported previous disease with symptoms suggestive of hantavirus cardiopulmonary syndrome. CONCLUSIONS: Human infections causing unreported cardiopulmonary syndrome probably occur in the southern State of Santa Catarina.

Prevalence of serum antibodies to hantavirus in a rural population from the southern state of Santa Catarina, Brazil / Prevalência de anticorpos séricos para hantavírus em população rural do extremo sul do estado de Santa Catarina, Brasil

INTRODUCTION: Rodent-borne hantaviruses cause severe human diseases. We completed a serological survey of hantavirus infection in rural inhabitants of Turvo County, in the southern State of Santa Catarina, Brazil, in which seropositivity for hantavirus was correlated to previous disease in the participants. METHODS: The levels of IgG antibodies to hantavirus Araraquara in the sera of 257 individuals were determined using an immunoenzymatic assay. RESULTS: IgG antibodies to hantavirus were found in 2.3 percent of the participants. All seropositive participants reported previous disease with symptoms suggestive of hantavirus cardiopulmonary syndrome. CONCLUSIONS: Human infections causing unreported cardiopulmonary syndrome probably occur in the southern State of Santa Catarina.

INTRODUÇÃO: Hantaviroses são zoonoses de roedores silvestres que causam doenças graves em seres humanos. Este trabalho mostra inquérito sorológico para hantavírus em população rural e periurbana do município de Turvo, Estado de Santa Catarina e a correlação da presença de anticorpos anti-hantavírus com a história mórbida pregressa dos indivíduos. MÉTODOS: Investigaram-se os 257 participantes do estudo quanto à presença de anticorpos IgG séricos anti-hantavírus Araraquara, por método imunoenzimático. RESULTADOS: A prevalência de anticorpos anti-hantavírus na população foi de 2,3 por cento. Os soropositivos possuíam antecedente nosológico sugestivo de hantavirose pregressa. CONCLUSÕES: Os achados mostram a ocorrência de infecções por hantavírus no extremo sul de Santa Catarina.

Diagnosis of hantavirus infection in humans and rodents in Ribeirão Preto, State of São Paulo, Brazil.

INTRODUCTION: Hantavirus pulmonary and cardiovascular syndrome (HPCS) is an emerging serious disease in the Americas. Hantaviruses (Bunyaviridae) are the causative agents of this syndrome and are mainly transmitted through inhalation of aerosols containing the excreta of wild rodents. In the Ribeirão Preto region (state of São Paulo, Brazil), HPCS has been reported since 1998, caused by the Araraquara virus (ARAV), for which Necromys lasiurus is the rodent reservoir. This study aimed to show diagnostic results relating to infection in humans and rodents, obtained at the Virology Research Center of the Ribeirão Preto School of Medicine, University of São Paulo, between 2005 and 2008. METHODS: HPCS was diagnosed by means of ELISA and/or RT-PCR in 11 (21.2%) out of 52 suspected cases, and 54.4% of these were fatal. Furthermore, 595 wild rodents (Necromys lasiurus, Akodon sp, Calomys tener and Oligoryzomys sp) were caught between 2005 and 2008. RESULTS: Fifteen (2.5%) of these rodents presented antibodies for hantavirus, as follows: Necromys lasiurus (4%), Calomys tener (1.9%) and Akodon sp (1.5%). Nucleotide sequences obtained through RT-PCR from one HPCS patient and one Calomys tener rodent were compared with hantavirus sequences from GenBank, which showed that both were homologous with ARAV. CONCLUSIONS: This work corroborates previous studies showing that ARAV is the hantavirus causing HPCS in the Ribeirão Preto region. It also shows that rodents infected with hantavirus represent a constant risk of transmission of this virus to man.

Diagnosis of hantavirus infection in humans and rodents in Ribeirão Preto, State of São Paulo, Brazil / Diagnóstico de infecção por hantavírus em humanos e roedores em Ribeirão Preto, Estado de São Paulo

INTRODUCTION: Hantavirus pulmonary and cardiovascular syndrome (HPCS) is an emerging serious disease in the Americas. Hantaviruses (Bunyaviridae) are the causative agents of this syndrome and are mainly transmitted through inhalation of aerosols containing the excreta of wild rodents. In the Ribeirão Preto region (state of São Paulo, Brazil), HPCS has been reported since 1998, caused by the Araraquara virus (ARAV), for which Necromys lasiurus is the rodent reservoir. This study aimed to show diagnostic results relating to infection in humans and rodents, obtained at the Virology Research Center of the Ribeirão Preto School of Medicine, University of São Paulo, between 2005 and 2008. METHODS: HPCS was diagnosed by means of ELISA and/or RT-PCR in 11 (21.2 percent) out of 52 suspected cases, and 54.4 percent of these were fatal. Furthermore, 595 wild rodents (Necromys lasiurus, Akodon sp, Calomys tener and Oligoryzomys sp) were caught between 2005 and 2008. RESULTS: Fifteen (2.5 percent) of these rodents presented antibodies for hantavirus, as follows: Necromys lasiurus (4 percent), Calomys tener (1.9 percent) and Akodon sp (1.5 percent). Nucleotide sequences obtained through RT-PCR from one HPCS patient and one Calomys tener rodent were compared with hantavirus sequences from GenBank, which showed that both were homologous with ARAV. CONCLUSIONS: This work corroborates previous studies showing that ARAV is the hantavirus causing HPCS in the Ribeirão Preto region. It also shows that rodents infected with hantavirus represent a constant risk of transmission of this virus to man.

INTRODUÇÃO: A síndrome pulmonar e cardiovascular por hantavírus é uma doença grave emergente nas Américas. Os hantavírus, Bunyaviridae, são os agentes causadores desta síndrome, causadas, principalmente, pela inalação de aerossóis dos dejetos de roedores silvestres. Na região de Ribeirão Preto, a SPCVH, causada pelo vírus Araraquara, tem sido diagnosticada, desde 1998. O roedor-reservatório do ARAV é o Necromys lasiurus. Este tem como objetivo mostrar os resultados de diagnósticos da infecção de humanos e roedores obtidos no Centro de Pesquisa em Virologia da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, durante o período de 2005 a 2008. MÉTODOS: A síndrome pulmonar e cardiovascular por hantavírus foi diagnosticada, por ELISA e/ou RT-PCR, em 11 (21,2 por cento) dos 52 casos suspeitos e destes, 54,4 por cento foram casos fatais. Além disso, também, de 2005 a 2008, foram capturados 595 roedores silvestres, Necromys lasiurus, Akodon sp, Calomys tener e Oligoryzomys sp. RESULTADOS: Quinze (2,5 por cento) destes roedores apresentaram anticorpos para hantavírus. As soropositividades intraespécie ou gênero foram 4 por cento para Necromys lasiurus, 1,9 por cento para Calomys tener e 1,5 por cento para Akodon sp. Sequências nucleotídicas, obtidas pela RT-PCR de um paciente com SPCVH e de um roedor Calomys tener, foram comparadas com sequências de hantavírus do GenBank, o que mostrou que ambas tinham homologia com o ARAV. CONCLUSÕES: Este trabalho corrobora outros estudos que mostram que o ARAV é o hantavírus causador da SPCVH, na região de Ribeirão Preto, além de mostrar que roedores infectados por hantavírus representam um risco constante de transmissão desses vírus para o homem.

Standardization of an ELISA test using a recombinant nucleoprotein from the Junin virus as the antigen and serological screening for arenavirus among the population of Nova Xavantina, State of Mato Grosso.

INTRODUCTION: Arenavirus hemorrhagic fever is a severe emerging disease. METHODS: Considering that the levels of antibodies against arenavirus in the Brazilian population are completely unknown, we have standardized an ELISA test for detecting IgG antibodies using a recombinant nucleoprotein from the Junin virus as the antigen. This protein was obtained by inserting the gene of the Junin virus nucleoprotein into the genome of Autographa californica nucleopolyhedrovirus, using the Bac-to-Bac baculovirus expression system. This recombinant baculovirus was used to infect S. frugiperda cells (SF9). RESULTS: The infection resulted in synthesis of high concentrations of recombinant protein. This protein was detected on 12.5% polyacrylamide gel and by means of Western blot. Using the standardized ELISA test, 343 samples from the population of Nova Xavantina were analyzed. We observed that 1.4% of the serum samples (five samples) presented antibody titers against arenavirus. CONCLUSIONS: These results show the population studied may present exposure to arenavirus infection.

Standardization of an ELISA test using a recombinant nucleoprotein from the Junin virus as the antigen and serological screening for arenavirus among the population of Nova Xavantina, State of Mato Grosso / Padronização de um teste de ELISA utilizando a nucleoproteína recombinante de vírus Junin como antígeno e triagem sorológica para Arenavírus na população de Nova Xavantina, Estado do Mato Grosso

INTRODUCTION: Arenavirus hemorrhagic fever is a severe emerging disease. METHODS: Considering that the levels of antibodies against arenavirus in the Brazilian population are completely unknown, we have standardized an ELISA test for detecting IgG antibodies using a recombinant nucleoprotein from the Junin virus as the antigen. This protein was obtained by inserting the gene of the Junin virus nucleoprotein into the genome of Autographa californica nucleopolyhedrovirus, using the Bac-to-Bac baculovirus expression system. This recombinant baculovirus was used to infect S. frugiperda cells (SF9). RESULTS: The infection resulted in synthesis of high concentrations of recombinant protein. This protein was detected on 12.5 percent polyacrylamide gel and by means of Western blot. Using the standardized ELISA test, 343 samples from the population of Nova Xavantina were analyzed. We observed that 1.4 percent of the serum samples (five samples) presented antibody titers against arenavirus. CONCLUSIONS: These results show the population studied may present exposure to arenavirus infection.

INTRODUÇÃO: A febre hemorrágica por Arenavirus é uma severa doença emergente. MÉTODOS: Considerando que os níveis de anticorpos contra Arenavirus na população brasileira é totalmente desconhecido, nos padronizamos um teste de ELISA para detecção de anticorpos IgG usando uma nucleoproteína recombinante do vírus Junin como antígeno. Esta proteína foi obtida pela inserção do gene da nucleoproteína do vírus Junin no genoma do vírus Autographa californica nucleopolyhedrovirus, utilizando o sistema de expressão em Baculovírus, Bac-To-Bac. Este baculovirus recombinante foi utilizado para infecção de células de S. frugiperda (Sf9). RESULTADOS: A infecção resultou na produção de altas concentrações de proteína recombinante. Esta proteína foi detectada em gel de poliacrilamida 12,5 por cento, e em Western blot. Utilizando o teste de ELISA padronizado, foram analizadas 343 amostras provenientes da população de Nova Xavantina. Observamos que 1,4 por cento dos soros (5 amostras) apresentavam títulos de anticorpos contra arenavírus. CONCLUSÕES: Estes resultados sugerem que a população estudada pode estar sendo exposta a infecções por arenavírus.

Association of -308G/A polymorphism in the tumor necrosis factor-alpha gene promoter with susceptibility to development of hantavirus cardiopulmonary syndrome in the Ribeirão Preto region, Brazil.

Activation of the immune response in hantavirus cardiopulmonary syndrome (HCPS) leads to a high TNF production, probably contributing to the disease. The polymorphic TNF2 allele (TNF -308G/A) has been associated with increased cytokine production. We investigated the association of the TNF2 allele with the outcome of hantavirus infection in Brazilian patients. A total of 122 hantavirus-exposed individuals (26 presenting HCPS and 96 only hantavirus seroconversion) were studied. The TNF2 allele was more frequently found in HCPS patients than in individuals with positive serology for hantavirus but without a history of HCPS illness, suggesting that the TNF2 allele could represent a risk factor for developing HCPS.

[Pulmonary and cardiovascular syndrome due to hantavirus: clinical aspects of an emerging disease in southeastern Brazil]. / Síndrome pulmonar e cardiovascular por hantavírus: aspectos clínicos de uma doença emergente no sudeste brasileiro.

Pulmonary and cardiovascular syndrome due to hantavirus is a disease caused by inhalation of aerosols from the excreta of wild rodents contaminated by viruses of the Bunyaviridae family. We studied the clinical and laboratory manifestations of 70 cases that occurred in the region of Ribeirão Preto, SP, Brazil, between 1998 and 2007. The frequency of symptoms was as follows: dyspnea (87%), fever (81%), coughing (44%), headache (34%), tachycardia (81%), low arterial blood pressure (56%), metabolic acidosis (57%), lymphocytopenia (51%), hematocrit > 45% (70%), leukocytosis with left deviation (67%), creatinine (51%) and urea (42%). Mortality (54.3%) occurred mainly on the fourth day. Respiratory insufficiency, low arterial blood pressure and shock occurred after 24 to 48 hours. High hematocrit and decreased platelet levels were signs strongly suggestive of the disease. The diagnostic hypothesis of atypical pneumonia was associated with a good prognosis (p = 0.0136). Fluid infusion greater than 2,000 ml and arterial hypotension were associated with a poor prognosis (p = 0.0286 and p = 0.0453).

Evaluation of an enzyme-linked immunosorbent assay based on Araraquara virus recombinant nucleocapsid protein.

Laboratory diagnosis of hantavirus cardiopulmonary syndrome (HCPS) in Brazil has been performed mostly by detection of IgM antibodies to recombinant antigen purified from Sin Nombre virus and Andes virus (ANDV). Recently, a recombinant nucleocapsid (rN) protein of Araraquara virus (ARAV), a Brazilian hantavirus, was obtained in Escherichia coli. To evaluate ARAV rN as antigen for antibody detection, serum samples from 30 patients from Argentina seropositive for hantavirus were tested. All samples were positive for IgG and IgM by enzyme-linked immunosorbent assay (ELISA) using either ARAV rN or ANDV rN antigens. In Brazil, six of 60 serum samples from patients with suspected HCPS (10%) were positive for IgM by ELISA using ARAV rN antigen and 7 were positive using ANDV rN antigen. For results obtained with 90 serum samples analyzed by IgM ELISA with ANDV rN antigen, the sensitivity of the IgM ELISA using ARAV rN antigen was 97.2%, the specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 98.1%. The results show that ARAV rN is a suitable antigen for diagnosis of hantavirus infection in Brazil and Argentina.

Síndrome pulmonar e cardiovascular por hantavírus: aspectos clínicos de uma doença emergente no sudeste brasileiro / Pulmonary and cardiovascular syndrome due to hantavirus: clinical aspects of an emerging disease in southeastern Brazil

A síndrome pulmonar e cardiovascular por hantavírus é doença causada pela aspiração de aerossóis dos dejetos de roedores silvestres contaminados por vírus da família Bunyaviridae. Estudamos manifestações clínicas e laboratoriais de 70 casos ocorridos de 1998 a 2007 na região de Ribeirão Preto, SP. A freqüência de sintomas foi dispnéia (87 por cento), febre (81 por cento), tosse (44 por cento), cefaléia (34 por cento), taquicardia (81 por cento), hipotensão arterial (56 por cento), hipóxia (49 por cento), acidose metabólica (57 por cento), linfocitopenia (51 por cento), hematócrito >45 por cento (70 por cento), leucocitose com desvio à esquerda (67 por cento), creatinina (51 por cento) e uréia (42 por cento) séricas elevadas. A letalidade (54,3 por cento) ocorreu principalmente no 4o dia. Insuficiência respiratória, hipotensão arterial e choque ocorreu 24-48 horas; o hematócrito elevado e a plaquetopenia são sinais fortemente sugestivos da doença. A hipótese diagnóstica de pneumonia atípica associada a bom prognóstico (p:0,0136); a infusão hídrica >2.000ml e hipotensão arterial associadas a mau prognóstico (p:0,0286 e p:0,0453).

Pulmonary and cardiovascular syndrome due to hantavirus is a disease caused by inhalation of aerosols from the excreta of wild rodents contaminated by viruses of the Bunyaviridae family. We studied the clinical and laboratory manifestations of 70 cases that occurred in the region of Ribeirão Preto, SP, Brazil, between 1998 and 2007. The frequency of symptoms was as follows: dyspnea (87 percent), fever (81 percent), coughing (44 percent), headache (34 percent), tachycardia (81 percent), low arterial blood pressure (56 percent), metabolic acidosis (57 percent), lymphocytopenia (51 percent), hematocrit > 45 percent (70 percent), leukocytosis with left deviation (67 percent), creatinine (51 percent) and urea (42 percent). Mortality (54.3 percent) occurred mainly on the fourth day. Respiratory insufficiency, low arterial blood pressure and shock occurred after 24 to 48 hours. High hematocrit and decreased platelet levels were signs strongly suggestive of the disease. The diagnostic hypothesis of atypical pneumonia was associated with a good prognosis (p = 0.0136). Fluid infusion greater than 2,000 ml and arterial hypotension were associated with a poor prognosis (p = 0.0286 and p = 0.0453).

Role of mixed Th1 and Th2 serum cytokines on pathogenesis and prognosis of hantavirus pulmonary syndrome.

The hantavirus pulmonary syndrome (HPS) is an emerging syndrome in the Americas. The disease results from intense immune activation and changes in vascular permeability. The aim of this study was to determine the profile of serum cytokines in HPS patients looking for correlation with the clinical parameters, severity and outcome of illness. Studying 21 HPS patients, we found that IL-6 may have an important role in the pathogenesis of HPS, being associated with fatal outcome. Our results also support a mixed Th1/Th2 immune response during the course of HPS and that the magnitude of Th1 response effector cytokines is correlated to HPS severity. The decreased levels of TGF-beta observed in HPS patients suggest that immunoregulatory activity could be damaged in these patients.