RESUMO
BACKGROUND: Zika virus (ZIKV) is an emerging arthropod-borne flavivirus transmitted by Aedes mosquitoes. Recent commentaries regarding ZIKV routes of transmission describe a potential transmission by transfusion. Herein, we report a probable case of transfusion-transmitted ZIKV infection through a platelet transfusion that was detected from postdonation information. CASE REPORT: A blood donor made a voluntary telephone report to the blood donor facility 3 days after donation and informed the facility of a febrile illness (fever, malaise, and headaches). Due to the ongoing dengue epidemic, the initial clinical investigation included dengue among other possible diagnoses. The serology and molecular laboratory results excluded dengue infection. However, stored samples from the donation were positive for ZIKV on reverse transcription-polymerase chain reaction (RT-PCR) analysis. A retrospective investigation demonstrated that the platelet concentrate, which was part of a pool, had been transfused after a liver transplantation. A physician had evaluated the patient 4 days after surgery. Laboratory investigation showed enzyme-linked immunosorbent assay results that were negative for dengue immunoglobulin M antibodies; however, the results were positive for hemagglutination inhibition antibodies against flavivirus. ZIKV RT-PCR and virus isolation analyses in cell cultures from recipient serum were both positive. The sequencing confirmed ZIKV in the donor and patient samples. Ten partial nucleotide sequences from the ZIKV strain that were detected in the donor were aligned and compared with the ZIKV genome detected in the recipient, revealing a 99.8% homology between the two strains. CONCLUSIONS: This is a case of probable transmission of ZIKV through blood transfusion. The patient had been transfused with the blood product from an infected donor, most likely in the incubation period after ZIKV infection but prior to clinical disease onset. This report emphasizes the importance of postdonation information and recipient investigations during outbreaks of potentially blood-borne infections.
Assuntos
Transfusão de Plaquetas/efeitos adversos , Torque teno virus/isolamento & purificação , Infecção por Zika virus/transmissão , Zika virus/isolamento & purificação , Doadores de Sangue , Plaquetas/virologia , Patógenos Transmitidos pelo Sangue , Brasil , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de RNA , Torque teno virus/genética , Zika virus/genética , Infecção por Zika virus/diagnósticoRESUMO
OBJECTIVE: To describe the epidemiological profile of pregnant women with suspected Zika virus infection, reported on the Center for Strategic Information for Health Surveillance System, in the state of São Paulo, Brazil, its range of abnormalities and/or pregnancy outcomes. METHODS: Descriptive epidemiological study of a cohort of symptomatic pregnant women with suspected Zika virus infection and their pregnancy outcomes, living in the state of São Paulo, reported between 2015-2018. RESULTS: Of the 2,329 pregnant women studied, 29.3% were confirmed to have the infection, almost half of them were single (44.8%), the majority of them were white woman (74.2%), with complete high school education (53.6%), and concentrated in the northeast region of the state. The proportion of newborns with central nervous system abnormalities was approximately 4.0%. CONCLUSION: The results found characterize Zika virus transmission in the state of São Paulo and may support public health actions in places with higher risk of disease transmission.
Assuntos
Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Brasil/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Infecção por Zika virus/epidemiologiaRESUMO
INTRODUCTION: The state of São Paulo has been monitoring cases of microcephaly and pregnant women presenting with acute rash, through CeVeSP. METHODS: This was a descriptive study focusing on pregnant women with rash and the outcome of their pregnancy, based on the notifications through the CeVeSP. RESULTS: During 2016, 2,209 cases of pregnant women with rash were reported and investigated. Of these, 36.6% were confirmed. Of the pregnant women who tested positive for ZIKV, 6.4% did not have a favorable outcome. CONCLUSIONS: Our results allowed the characterization of pregnant women exposed to ZIKV and the outcome of pregnancy.
Assuntos
Exantema/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Vigilância de Evento Sentinela , Infecção por Zika virus/diagnóstico , Adolescente , Adulto , Brasil/epidemiologia , Exantema/epidemiologia , Exantema/virologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Adulto Jovem , Infecção por Zika virus/epidemiologiaRESUMO
OBJECTIVE: to characterize cases of congenital syndrome associated with Zika virus infection (CZS) and other infectious etiologies, resident in the state of São Paulo, Brazil, from October 30, 2015, to June 30, 2017. METHODS: this was a descriptive study of suspected cases of CZS and other infectious etiologies notified on the Public Health Events Registry. RESULTS: 960 cases were investigated up to epidemiological week 26/2017, and 146 were confirmed for congenital infection; of these, 59 (40.4%) were confirmed for congenital infection without etiological identification and 87 (59.6%) with laboratory confirmation, of which 55 were congenital syndrome associated with Zika virus and 32 were congenital syndrome associated with other infectious agents. CONCLUSION: this study enabled the detection of 23.9% CZS cases among suspected cases of infectious etiology.
Assuntos
Anormalidades Congênitas/epidemiologia , Microcefalia/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Infecção por Zika virus/epidemiologia , Brasil/epidemiologia , Anormalidades Congênitas/virologia , Feminino , Humanos , Recém-Nascido , Masculino , Microcefalia/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Sistema de Registros , Síndrome , Infecção por Zika virus/complicações , Infecção por Zika virus/congênitoRESUMO
Brazilian spotted fever (BSF) is the most important tick-borne disease in Brazil and is caused by Rickettsia rickettsii and transmitted by the Ixodid tick Amblyomma cajennense, its main vector. We present epidemiologic aspects of a case series of patients admitted to the Hospital das Clínicas da UNICAMP from 1985 to 2003 with a confirmed diagnosis of BSF either by a fourfold rise in indirect immunofluorescence (IFA) titers of IgG antibodies reactive with R. rickettsii or isolation of R. rickettsii from blood or skin specimens. Seasonal variation of case occurrence seems to be associated with the life cycle of the tick. The recent reemergence of cases seems to be associated with the growing numbers of the capybara (Hydrochaeris hydrochaeris) and their expansion into urban areas.
Assuntos
Infecções por Rickettsia/epidemiologia , Febre Maculosa das Montanhas Rochosas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Incidência , Pessoa de Meia-Idade , Rickettsia rickettsii/isolamento & purificaçãoRESUMO
This case series study is based on a retrospective review of medical records and case notification files of patients admitted to The Hospital das Clínicas da UNICAMP from 1985 to 2003 with a confirmed diagnosis of BSF either by fourfold rise in indirect immunofluorescence assay (IFA) titers of IgG antibodies reactive with R. rickettsii or isolation of R. rickettsii from blood or skin specimens. A median lethality of 41.9 % was observed between 1985 and 2004. The case-fatality ratio of 30 % in our study, lower than the overall São Paulo state ratio, could be explained by a higher index of suspicion and a larger experience in our hospital, a regional referral center for BSF. The presence of the classical triad of fever, rash, and headache as described in RMSF was observed in fever than half (35.2%) of our patients.
Assuntos
Infecções por Rickettsia/epidemiologia , Brasil/epidemiologia , Humanos , Incidência , Prontuários Médicos , Estudos Retrospectivos , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/mortalidade , Análise de SobrevidaRESUMO
We report here the genome sequence of Zika virus, strain ZikaSPH2015, containing all structural and nonstructural proteins flanked by the 5' and 3' untranslated region. It was isolated in São Paulo state, Brazil, in 2015, from a patient who received a blood transfusion from an asymptomatic donor at the time of donation.
RESUMO
This paper reports the isolation of St. Louis encephalitis virus (SLEV) from a febrile human case suspected to be dengue, in São Pedro, São Paulo State. A MAC-ELISA done on the patient's acute and convalescent sera was inconclusive and hemagglutination inhibition test detected IgG antibody for flaviviruses. An indirect immunofluorescent assay done on the C6/36 cell culture inoculated with the acute serum was positive for flaviviruses but negative when tested with dengue monoclonal antibodies. RNA extracted from the infected cell culture supernatant was amplified by RT-PCR in the presence of NS5 universal flavivirus primers and directly sequenced. Results of BLAST search indicated that this sequence shares 93% nucleotide similarity with the sequence of SLEV (strain-MSI.7), confirmed by RT-PCR performed with SLEV specific primers. Since SLEV was identified as the cause of human disease, it is necessary to improve surveillance in order to achieve early detection of this agent in the state of São Paulo and in Brazil. This finding is also an alert to health professionals about the need for more complete clinical and epidemiological investigations of febrile illnesses as in the reported case. SLEV infections can be unrecognized or confused with other ones caused by an arbovirus, such as dengue.
Assuntos
Anticorpos Antivirais/sangue , Vírus da Encefalite de St. Louis/isolamento & purificação , Encefalite de St. Louis/diagnóstico , Brasil , Vírus da Encefalite de St. Louis/genética , Vírus da Encefalite de St. Louis/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina G/sangue , Pessoa de Meia-Idade , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Urban heat islands are characterized by high land surface temperature, low humidity, and poor vegetation, and considered to favor the transmission of the mosquito-borne dengue fever that is transmitted by the Aedes aegypti mosquito. We analyzed the recorded dengue incidence in Sao Paulo city, Brazil, in 2010-2011, in terms of multiple environmental and socioeconomic variables. Geographical information systems, thermal remote sensing images, and census data were used to classify city areas according to land surface temperature, vegetation cover, population density, socioeconomic status, and housing standards. Of the 7415 dengue cases, a majority (93.1%) mapped to areas with land surface temperature >28°C. The dengue incidence rate (cases per 100,000 inhabitants) was low (3.2 cases) in high vegetation cover areas, but high (72.3 cases) in low vegetation cover areas where the land surface temperature was 29±2°C. Interestingly, a multiple cluster analysis phenogram showed more dengue cases clustered in areas of land surface temperature >32°C, than in areas characterized as low socioeconomic zones, high population density areas, or slum-like areas. In laboratory experiments, A. aegypti mosquito larval development, blood feeding, and oviposition associated positively with temperatures of 28-32°C, indicating these temperatures to be favorable for dengue transmission. Thus, among all the variables studied, dengue incidence was most affected by the temperature.
Assuntos
Aedes/fisiologia , Dengue/epidemiologia , Temperatura Alta , Insetos Vetores/fisiologia , Animais , Brasil/epidemiologia , Cidades/epidemiologia , Análise por Conglomerados , Dengue/transmissão , Comportamento Alimentar/fisiologia , Sistemas de Informação Geográfica , Humanos , Incidência , Oviposição/fisiologia , Tecnologia de Sensoriamento Remoto , Estações do Ano , Fatores Socioeconômicos , População UrbanaRESUMO
Abstract INTRODUCTION: The state of São Paulo has been monitoring cases of microcephaly and pregnant women presenting with acute rash, through CeVeSP. METHODS: This was a descriptive study focusing on pregnant women with rash and the outcome of their pregnancy, based on the notifications through the CeVeSP. RESULTS: During 2016, 2,209 cases of pregnant women with rash were reported and investigated. Of these, 36.6% were confirmed. Of the pregnant women who tested positive for ZIKV, 6.4% did not have a favorable outcome. CONCLUSIONS Our results allowed the characterization of pregnant women exposed to ZIKV and the outcome of pregnancy.
Assuntos
Humanos , Feminino , Gravidez , Adolescente , Adulto , Adulto Jovem , Complicações Infecciosas na Gravidez/diagnóstico , Vigilância de Evento Sentinela , Exantema/diagnóstico , Infecção por Zika virus/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Brasil/epidemiologia , Exantema/epidemiologia , Exantema/virologia , Infecção por Zika virus/epidemiologiaRESUMO
INTRODUCTION: The state of São Paulo has been monitoring cases of microcephaly and pregnant women presenting with acute rash, through CeVeSP. METHODS: This was a descriptive study focusing on pregnant women with rash and the outcome of their pregnancy, based on the notifications through the CeVeSP. RESULTS: During 2016, 2,209 cases of pregnant women with rash were reported and investigated. Of these, 36.6% were confirmed. Of the pregnant women who tested positive for ZIKV, 6.4% did not have a favorable outcome. CONCLUSIONS Our results allowed the characterization of pregnant women exposed to ZIKV and the outcome of pregnancy.
Assuntos
Organização Mundial da Saúde , Monitoramento Ambiental , Estado , Gestantes , Zika virusRESUMO
Objetivo: caracterizar os casos de síndrome congênita associada à infecção pelo ZIKV (SCZ) e outras etiologias infeciosas, residentes no estado de São Paulo, Brasil, no período de 30 de outubro de 2015 a 30 de junho de 2017. Métodos: estudo descritivo dos casos suspeitos de SCZ e outras etiologias infecciosas notificados no Registro de Eventos em Saúde Pública. Resultados: foram investigados 960 casos até a semana epidemiológica 26/2017, sendo confirmados 146 para infecção congênita; destes, 59 (40,4%) foram confirmados para infecção congênita sem identificação etiológica e 87 (59,6%) com confirmação laboratorial, sendo 55 com SCZ e 32 com síndrome congênita associada a outros agentes infecciosos. Conclusão: este estudo permitiu detectar 23,9% de casos de SCZ entre os casos suspeitos de etiologia infecciosa.
Objetivo: caracterizar los casos sospechosos de síndrome congénita asociada a la infección por virus Zika (SCZ) y otras etiologías infecciosas residentes en el estado de São Paulo, Brasil, en el período de 30 de octubre de 2015 a 30 de junio de 2017. Métodos: estudio descriptivo de los casos sospechosos de síndrome congénita asociada a la infección por el virus Zika y otras etiologías infecciosas notificadas en el Registro de Eventos en Salud Pública. Resultados: se han investigado 960 casos hasta la semana epidemiológica 26/2017, siendo confirmados 146 para la infección congénita; de estos, 59 fueron confirmados para infección congénita sin identificación etiológica y 87 con identificación etiológica, siendo 55 síndrome congénita asociados al virus Zika y 32 síndrome congénita asociado a otros agentes infecciosos. Conclusión: este estudio permitió detectar una tasa del 23,9% de casos de SCZ entre los casos sospechosos de etiología infecciosa.
Objective: to characterize cases of congenital syndrome associated with Zika virus infection (CZS) and other infectious etiologies, resident in the state of São Paulo, Brazil, from October 30, 2015, to June 30, 2017. Methods: this was a descriptive study of suspected cases of CZS and other infectious etiologies notified on the Public Health Events Registry. Results: 960 cases were investigated up to epidemiological week 26/2017, and 146 were confirmed for congenital infection; of these, 59 (40.4%) were confirmed for congenital infection without etiological identification and 87 (59.6%) with laboratory confirmation, of which 55 were congenital syndrome associated with Zika virus and 32 were congenital syndrome associated with other infectious agents. Conclusion: this study enabled the detection of 23.9% CZS cases among suspected cases of infectious etiology.
Assuntos
Humanos , Masculino , Feminino , Anormalidades Congênitas , Epidemiologia Descritiva , Zika virus , Microcefalia/epidemiologiaRESUMO
Suspicion of Brazilian spotted fever (BSF) should occur in endemic regions upon surveillance of the acute febrile icteric hemorrhagic syndrome (AFIHS). However, limitations associated with currently available laboratory tests pose a challenge to early diagnosis, especially in fatal cases. Two real-time PCR (qPCR) protocols were evaluated to diagnose BSF in 110 fatal AFIHS cases, collected in BSF-endemic regions in 2009-2010. Of these, 24 were positive and 86 negative by indirect immunofluorescence (IFA) assay (cut-off IgG and/or IgM ≥ 128). DNA from these samples was used in the qPCR protocols: one to detect Rickettsia spp. (citrate synthase gene) and another to determine spotted fever group (SFG) Rickettsia species (OmpA gene). Of the 24 IFA-positive samples, 5 (21%) were positive for OmpA and 9 (38%) for citrate synthase. In the IFA-negative group (n=86), OmpA and citrate synthase were positive in 23 (27%) and 27 (31%), respectively. These results showed that the 2 qPCR protocols were about twice as sensitive as the IFA test alone (93% concordance). In conclusion, qPCR is a sensitive method for the diagnosis of fatal BSF cases and should be considered for routine surveillance of AFIHS in places like Brazil, where spotted fever-related lethality is high and other endemic diseases like dengue and leptospirosis can mislead diagnosis.
Assuntos
Técnicas de Diagnóstico Molecular/métodos , Patologia Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Rickettsia/isolamento & purificação , Febre Maculosa das Montanhas Rochosas/diagnóstico , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/genética , Brasil , Citrato (si)-Sintase/genética , DNA Bacteriano/genética , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Rickettsia/genética , Sensibilidade e EspecificidadeRESUMO
Brazilian spotted fever (BSF) caused by Rickettsia rickettsii is the most important rickettsiosis and the only reportable tick-borne disease in Brazil. In Brazil, the hard tick Amblyomma cajennense is the most important BSF vector; however, in São Paulo State, A. aureolatum was also recognized as a vector species in remaining Atlantic forest areas near the metropolitan area of São Paulo city. We analyzed clinical and epidemiological features of BSF cases from two distinct areas where A. cajennense (Area 1) and A. aureolatum (Area 2) are the incriminated vectors. The clinical features demonstrate the same severity pattern of BSF in both endemic areas. Differences in seasonality, patient characteristics (median age and gender), and epidemiological risk factors (animals host contact and vegetation characteristics) were observed and possibly could be attributed to the characteristics of each vector and their typical biological cycle (hosts and environment).
Assuntos
Doenças Endêmicas , Rickettsia rickettsii/isolamento & purificação , Febre Maculosa das Montanhas Rochosas/epidemiologia , Febre Maculosa das Montanhas Rochosas/patologia , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Ixodidae/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
The present work evaluated the diagnostic accuracy of detection of Dengue NS1 antigen employing two NS1 assays, an immunochromatographic assay and ELISA, in the diagnostic routine of Public Health laboratories. The results obtained with NS1 assay were compared with virus isolation and, in a subpopulation of cases, they were compared with the IgM-ELISA results obtained with convalescent samples. A total of 2,321 sera samples were analyzed by one of two NS1 techniques from March to October 2009. The samples were divided into five groups: groups I, II and III included samples tested by NS1 and virus isolation, and groups IV and V included patients with a first sample tested by NS1 and a second sample tested by IgM-ELISA. Sensitivity, specificity, positive and negative predictive values, Kappa Index and Kappa Concordance were calculated. The results showed that NS1 testing in groups I, II and III had high sensitivity (98.0%, 99.5% and 99.3%), and predictive values and Kappa index between 0.9 - 1.0. Groups IV and V only had Kappa Concordance calculated, since the samples were analyzed according to the presence of NS1 antigen or IgM antibody. Concordance of 92.1% was observed when comparing the results of NS1-negative samples with IgM-ELISA. Based on the findings, it is possible to suggest that the tests for NS1 detection may be important tools for monitoring the introduction and spread of Dengue serotypes.
Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Vírus da Dengue/imunologia , Dengue/diagnóstico , Imunoglobulina M/sangue , Proteínas não Estruturais Virais/imunologia , Cromatografia de Afinidade , Dengue/imunologia , Dengue/virologia , Ensaio de Imunoadsorção Enzimática , Humanos , Sensibilidade e EspecificidadeRESUMO
Urban heat islands are characterized by high land surface temperature, low humidity, and poor vegetation, and considered to favor the transmission of the mosquito-borne dengue fever that is transmitted by the Aedes aegypti mosquito. We analyzed the recorded dengue incidence in Sao Paulo city, Brazil, in 2010-2011, in terms of multiple environmental and socioeconomic variables. Geographical information systems, thermal remote sensing images, and census data were used to classify city areas according to land surface temper- ature, vegetation cover, population density, socioeconomic status, and housing standards. Of the 7415 dengue cases, a majority (93.1%) mapped to areas with land surface temperature >28 ◦ C. The dengue incidence rate (cases per 100,000 inhabitants) was low (3.2 cases) in high vegetation cover areas, but high (72.3 cases) in low vegetation cover areas where the land surface temperature was 29 ± 2 ◦ C. Interestingly, a multiple cluster analysis phenogram showed more dengue cases clustered in areas of land surface temperature >32 ◦ C, than in areas characterized as low socioeconomic zones, high population density areas, or slum-like areas. In laboratory experiments, A. aegypti mosquito larval development, blood feeding, and oviposition associated positively with temperatures of 28-32 ◦ C, indicating these temperatures to be favorable for dengue transmission. Thus, among all the variables studied, dengue incidence was most affected by the temperature.
Assuntos
Animais , Humanos , Aedes/fisiologia , Dengue/epidemiologia , Temperatura Alta , Insetos Vetores/fisiologia , Brasil/epidemiologia , Análise por Conglomerados , Cidades/epidemiologia , Dengue/transmissão , Comportamento Alimentar/fisiologia , Sistemas de Informação Geográfica , Incidência , Oviposição/fisiologia , Tecnologia de Sensoriamento Remoto , Estações do Ano , Fatores Socioeconômicos , População UrbanaRESUMO
O vírus dengue, pertencente à família Flaviviridae, gênero Flavivirus, é constituído de RNA de fita simples que codifica proteínas estruturais e não estruturais. Possui quatro sorotipos: DENV-1, DENV-2, DENV-3 e DENV-4. O diagnóstico laboratorial rápido podeser de grande ajuda no controle da expansão da doença. O objetivo deste trabalho foi avaliar diferentes kits de detecção da proteína NS1 do vírus dengue, tendo como referência o isolamento viral. Foram utilizadas 147 amostras de soro de pacientes com suspeita de infecção pelo DENV, das quais 64 foram recebidas para isolamento devírus e 83 para ELISA IgM. O kit Dengue NS1 Ag Strip (Bio-Rad) obteve sensibilidade de 89%, especificidade de 66%, VPP 67% e VPN 88%. O Dengue Duo Test (Bioeasy) teve sensibilidade de 89%, especificidade 68%, VPP 70% e VPN 88%. O Platelia Dengue NS1ELISA Ag (Bio-Rad) apresentou sensibilidade de 95%, especificidade47%, VPP 59% e VPN 92%. O kit dengue Early ELISA (Panbio) resultou em sensibilidade de 86%, especificidade 71%, VPP 69% e VPN 86%. De forma geral, os kits avaliados podem ser empregados no diagnóstico, sempre associados a critério clínico e epidemiológico ou outros métodos laboratoriais
Assuntos
Animais , Dengue , Dengue/diagnóstico , Dengue/virologiaRESUMO
The present work evaluated the diagnostic accuracy of detection of Dengue NS1 antigen employing two NS1 assays, an immunochromatographic assay and ELISA, in the diagnostic routine of Public Health laboratories. The results obtained with NS1 assay were compared with virus isolation and, in a subpopulation of cases, they were compared with the IgM-ELISA results obtained with convalescent samples. A total of 2,321 sera samples were analyzed by one of two NS1 techniques from March to October 2009. The samples were divided into five groups: groups I, II and III included samples tested by NS1 and virus isolation, and groups IV and V included patients with a first sample tested by NS1 and a second sample tested by IgM-ELISA. Sensitivity, specificity, positive and negative predictive values, Kappa Index and Kappa Concordance were calculated. The results showed that NS1 testing in groups I, II and III had high sensitivity (98.0 percent, 99.5 percent and 99.3 percent), and predictive values and Kappa index between 0.9 - 1.0. Groups IV and V only had Kappa Concordance calculated, since the samples were analyzed according to the presence of NS1 antigen or IgM antibody. Concordance of 92.1 percent was observed when comparing the results of NS1-negative samples with IgM-ELISA. Based on the findings, it is possible to suggest that the tests for NS1 detection may be important tools for monitoring the introduction and spread of Dengue serotypes.
Esse estudo avaliou a acurácia do diagnóstico por detecção do antígeno NS1 do vírus Dengue empregando-se ensaios em dois formatos, imunocromatográfico e ELISA, na rotina diagnóstica dos laboratórios de Saúde Pública. Compararam-se os resultados de NS1 com os resultados de isolamento viral e, em parte dos casos, foi feita a comparação com os resultados de IgM-ELISA, obtidos nas segundas amostras. Um total de 2.321 amostras de soros, obtidas no período de março a outubro de 2009, foram analisadas por uma das duas técnicas NS1. As amostras foram divididas em cinco grupos: I, II e III, que incluíram amostras analisadas por testes NS1 e por isolamento de vírus. Os grupos IV e V incluíram pacientes com a primeira amostra processada por NS1 e segunda por IgM-ELISA. Foram analisadas sensibilidade, especificidade, valor preditivo positivo e negativo, concordância e índice Kappa. Os resultados mostraram que os grupos I, II e III apresentaram alta sensibilidade (98,0 por cento, 99,5 por cento e 99,3 por cento), valores preditivos e índice Kappa entre 0,9 - 1,0. Nos grupos IV e V, apenas concordância foi calculada, dado que as amostras foram analisadas quanto à presença de antígeno NS1 ou de anticorpos IgM. Comparando-se os resultados negativos de NS1 com IgM-ELISA houve 92,1 por cento de concordância. Com base nas constatações feitas, é possível sugerir que a detecção de NS1 pode ser importante ferramenta para monitorar a introdução e disseminação dos sorotipos de Dengue.