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1.
Mem Inst Oswaldo Cruz ; 115: e200287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533869

RESUMO

BACKGROUND: The heat-labile nature of Dengue virus (DENV) in serum samples must be considered when applying routine diagnostic tests to avoid issues that could impact the accuracy of test results with direct implications for case management and disease reporting. OBJECTIVES: To check if pre-analytical variables, such as storage time and temperature, have an impact on the accuracy of the main routine diagnostic tests for dengue. METHODS: Virus isolation, reverse transcription real-time polymerase chain reaction (RT-PCR) and NS1 enzyme-linked immunosorbent assay (ELISA) were evaluated using 84 samples submitted to different pre-analytical conditions. FINDINGS: Sensitivity and negative predictive value were directly affected by sample storage conditions. RT-PCR and virus isolation showed greater dependence on well-conserved samples for an accurate diagnosis. Interestingly, even storage at -30ºC for a relatively short time (15 days) was not adequate for accurate results using virus isolation and RT-PCR tests. On the other hand, NS1 ELISA showed no significant reduction in positivity for aliquots tested under the same conditions as in the previous tests. MAIN CONCLUSIONS: Our results support the stability of the NS1 marker in ELISA diagnosis and indicate that the accuracy of routine tests such as virus isolation and RT-PCR is significantly affected by inadequate transport and storage conditions of serum samples.


Assuntos
Antígenos Virais/sangue , Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Proteínas não Estruturais Virais/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Dengue/sangue , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/genética
2.
BMC Infect Dis ; 21(1): 96, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478432

RESUMO

BACKGROUND: Dengue virus infection has been an important and serious public health concern in Taiwan, where local outbreaks of dengue fever occurred almost every year. To our knowledge, no nationwide investigation has been carried out to determine the actual extent of infection in the general population. METHODS: A total of 1308 random serum samples were collected from the general population in Taiwan in 2010. The antibody-captured enzyme-linked immunosorbent assays were used to detect DENV-specific IgM and IgG. Demographics data were used for risk analysis. RESULTS: The weighted overall seroprevalence was 1.96% for anti-DENV IgM, and 3.4% for anti-DENV IgG, respectively. A significant rise of DENV IgG seropositive rate had been noted since late adulthood stage, from 1.1% at the age group of 50-59 years to 7.6% at the age group of 60-69 years. For people aged over 70 years, the seropositive rate reached 19%. Age, nationality, and regions of residency were associated with the IgG seropositivity. There was no statistically significant difference in seroprevalence of anti-Dengue IgM, indicating recent infection, among univariate predictors we proposed, including gender, age, residency, nationality, and household size. CONCLUSIONS: Our results indicated that the majority of population in Taiwan born after 1940 is naive to dengue virus and the prevalence of IgG antibody against dengue virus rises with age. Nationality, and regions of residency are associated with the exposure of population to infection by dengue viruses. Further studies are needed to realize the current situation of seroprevalence of dengue fever in Taiwan.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Dengue/sangue , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Taiwan/epidemiologia , Adulto Jovem
3.
BMC Infect Dis ; 21(1): 104, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482756

RESUMO

BACKGROUND: Dengue virus (DENV) infection is increasingly common in southern China and can be transmitted through blood transfusion but is not currently part of donor screening throughout the region. We assessed DENV prevalence among donors at the Xishuangbanna Blood Center, Yunnan, to support development of DENV screening strategies. METHODS: Blood samples were collected randomly between June 2019 and August 2019. These were screened for anti-DENV IgG and IgM using enzyme-linked immunosorbent assay (ELISA). Then, all reactive samples and some randomly-chosen non-reactive samples were used to detect DENV RNAs using real-time polymerase-chain-reaction (RT-PCR) assays. After RT-PCR, samples were further tested for soluble nonstructural protein 1 (NS1) using the colloidal gold method. Donors demographics were also collected and assessed. RESULTS: Over the study period, 2254 donor samples were collected and tested for anti-DENV IgG and IgM by ELISA. This revealed 598 anti-DENV IgG and/or IgM reactive samples, a serological prevalence of 26.53%. Of these, 26 were RT-PCR positive and/or NS1 positive. Significant differences in DENV prevalence were noted by occupation (P = 0.001), education (P < 0.001), and ethnicity (P = 0.026). CONCLUSION: The prevalence of DENV in Xishuangbanna Blood Center was higher than most other blood centers that have implemented DENV donor screening. Our study provides first-hand data about the prevalence of DENV and allows the development of a screening strategy for clinical use.


Assuntos
Doadores de Sangue , Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Dengue/epidemiologia , Programas de Rastreamento/métodos , Adulto , Anticorpos Antivirais/sangue , China/epidemiologia , Dengue/sangue , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Feminino , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Prevalência , RNA Viral/genética , Proteínas não Estruturais Virais/genética , Adulto Jovem
4.
BMC Infect Dis ; 20(1): 639, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867694

RESUMO

BACKGROUND: Dengue fever is an arthropod vector-borne disease transmitted to humans by infected Aedes mosquitoes. Ethiopia has a favorable ecology for arthropods and report high burden of acute febrile illnesses. However, the contribution of arboviral infections to the burden of acute febrile illnesses is barely known. In this study the seropositivity to dengue virus infection and associated risk factors were assessed in Arba Minch districts, southern Ethiopia. METHODS: An institution based cross-sectional study was conducted in a consecutive group of 529 acute febrile patients between May to August 2016. Socio-demographic data, residence place and clinical signs and symptoms were collected using structured questionnaires. Sera were tested for anti-dengue IgG and IgM using Euroimmune indirect immunofluorescent assay. Data analysis was done using SPSS V-20 (IBM Corp, 2012). P-value < 0.05 was taken as statistically significant. RESULT: Seropositivity was 25.1% (133/529) and 8.1% (43/529) for anti- IgG and IgM respectively. CONCLUSION: The high IgM prevalence detected indicate the probability of active transmission with a potential of public health significance that calls for a proactive follow up of the communities in the study area to forecast and avert the risk.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/sangue , Dengue/epidemiologia , Febre/sangue , Febre/epidemiologia , Adolescente , Adulto , Animais , Estudos Transversais , Dengue/diagnóstico , Dengue/virologia , Etiópia/epidemiologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
6.
PLoS Negl Trop Dis ; 14(7): e0008061, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32687540

RESUMO

Tanzania has recently experienced outbreaks of dengue in two coastal regions of Dar es Salaam and Tanga. Chikungunya and Rift Valley Fever outbreaks have also been recorded in the past decade. Little is known on the burden of the arboviral disease causing viruses (Dengue, Rift Valley and Chikungunya) endemically in the inter-epidemic periods. We aimed at determining the prevalence of the dengue, rift valley and chikungunya among humans in two geo ecologically distinct sites. The community-based cross-sectional study was conducted in Magugu in Manyara region and Wami-Dakawa in Morogoro region in Tanzania. Venous blood was collected from participants of all age groups, serum prepared from samples and subjected to ELISA tests for RVFV IgG/IgM, DENV IgG/IgM, and CHIKV IgM/IgG. Samples that were positive for IgM ELISA tests were subjected to a quantitative RT PCR for each virus. A structured questionnaire was used to collect socio-demographic information. Data analysis was performed by using SPSSv22. A total of 191 individuals from both sites participated in the study. Only one individual was CHIKV seropositive in Magugu, but none was seropositive or positive for either RVFV or DENV. Of the 122 individuals from Wami-Dakawa site, 16.39% (n = 20) had recent exposure to RVFV while 9.83% (n = 12) were seropositive for CHIKV. All samples were negative by RVFV and CHIKV qPCR. Neither infection nor exposure to DENV was observed in participants from both sites. Being more than 5 in a household, having no formal education and having recently travelled to an urban area were risk factors associated with RVFV and CHIKV seropositivity. We report a considerable exposure to RVFV and CHIKV among Wami-Dakawa residents during the dry season and an absence of exposure of the viruses among humans in Magugu site. In both sites, neither DENV exposure nor infection was detected.


Assuntos
Anticorpos Antivirais/sangue , Febre de Chikungunya/sangue , Vírus Chikungunya/imunologia , Vírus da Dengue/imunologia , Dengue/sangue , Febre do Vale de Rift/sangue , Vírus da Febre do Vale do Rift/imunologia , Adulto , Animais , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/fisiologia , Estudos Transversais , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/fisiologia , Feminino , Humanos , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Febre do Vale de Rift/epidemiologia , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/fisiologia , Estudos Soroepidemiológicos , Tanzânia/epidemiologia , Adulto Jovem
7.
Am J Trop Med Hyg ; 103(1): 112-119, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32431270

RESUMO

This study describes the natural history of dengue virus (DENV) infection in rhesus monkeys exposed to the bites of DENV-infected Aedes aegypti mosquitoes. Dengue virus-infected mosquitoes were generated by either intrathoracic inoculation or by oral feeding on viremic blood meals. Each of the six rhesus monkeys that were fed upon by intrathoracically infected mosquitoes developed non-structural protein 1 (NS1) antigenemia and an IgM response; viremia was detected in 4/6 individuals. No virological or immunological evidence of DENV infection was detected in the three monkeys exposed to mosquitoes that had been orally infected with DENV. These results demonstrate the utility of mosquito-borne challenge of rhesus monkeys with DENV.


Assuntos
Aedes/virologia , Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/imunologia , Imunoglobulina M/sangue , Mosquitos Vetores/virologia , Viremia/imunologia , Animais , Dengue/sangue , Dengue/diagnóstico , Dengue/transmissão , Vírus da Dengue/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Macaca mulatta , Projetos Piloto , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas não Estruturais Virais/genética , Viremia/sangue , Viremia/diagnóstico , Viremia/transmissão
8.
J Infect Public Health ; 13(5): 724-729, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32224108

RESUMO

BACKGROUND: The co-circulation of Chikungunya (CHIKV), Dengue (DENV) and Zika (ZIKV) viruses increased the risk of outbreaks and coinfections among them. Here, we report cases of coinfection in clinical samples from state of Tocantins, Brazil. METHODS: In 2017, the Central Public Health Laboratory (LACEN) received samples of patients who consulted health units with symptoms compatible with arboviral infections. A total of 102 samples were sent to the Retrovirology Laboratory at the Federal University of São Paulo, where they were tested by RT-qPCR to confirm DENV, ZIKV and CHIKV infections and to detect coinfected patients. RESULTS: We identified with CHIKV monoinfection (52), DENV serotypes 1 (28) and serotypes 2 (22). We did not detect ZIKV. Five patients were characterized with coinfection involving CHIKV and DENV serotype 2. CONCLUSIONS: The presence of co-circulating arboviruses increases the chance of coinfection and demonstrates the importance of differential diagnosis and vector control.


Assuntos
Febre de Chikungunya/epidemiologia , Coinfecção/epidemiologia , Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Febre de Chikungunya/sangue , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Criança , Coinfecção/diagnóstico , Estudos Transversais , Dengue/sangue , Dengue/diagnóstico , Dengue/genética , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorogrupo , Adulto Jovem , Zika virus/isolamento & purificação , Infecção por Zika virus/sangue
9.
Sci Rep ; 10(1): 6351, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286360

RESUMO

Dengue virus (DENV) co-circulation in Brazil represents a challenge for treatment and vaccine development. Despite public health impact, the occurrence of coinfections with other viruses is a common event. Increased T cell activation and altered inflammatory response are found during DENV coinfection with Human Immunodeficiency Virus (HIV) impacting HIV-pathogenesis. Even with Antiretroviral therapy (ART), HIV- treated patients had chronic immune activation and lymphocyte apoptosis. However, apoptotic mechanisms have not been investigated during coinfection with DENV. Our attention was attracted to apoptotic cell markers expressions in PBMCs from DENV and DENV/HIV coinfected patients. We found CD4/CD8 ratio inversion in most coinfected patients. CD4 T and CD8 T-cell subsets from DENV and DENV/HIV groups expressed low levels of anti-apoptotic protein Bcl-2. Furthermore, CD8 CD95 double positive cells frequency expressing low levels of Bcl-2 were significantly higher in these patients. Additionally, the density of Bcl-2 on classical monocytes (CD14++CD16-) was significantly lower during DENV infection. Upregulation of pro-apoptotic proteins and anti-apoptotic proteins were found in DENV and DENV/HIV, while catalase, an antioxidant protein, was upregulated mainly in DENV/HIV coinfection. These findings provide evidence of apoptosis triggering during DENV/HIV coinfection, which may contribute to knowledge of immunological response during DENV acute infection in HIV-patients treated with ART.


Assuntos
Apoptose/genética , Dengue/sangue , Infecções por HIV/sangue , Subpopulações de Linfócitos T/imunologia , Doença Aguda/epidemiologia , Adulto , Idoso , Brasil/epidemiologia , Relação CD4-CD8 , Linfócitos T CD8-Positivos/imunologia , Coinfecção/sangue , Coinfecção/imunologia , Coinfecção/virologia , Dengue/imunologia , Dengue/patologia , Dengue/virologia , Vírus da Dengue/patogenicidade , Feminino , HIV/patogenicidade , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , Humanos , Leucócitos Mononucleares/virologia , Ativação Linfocitária/genética , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Subpopulações de Linfócitos T/patologia , Adulto Jovem
10.
Am J Trop Med Hyg ; 102(6): 1217-1225, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32189614

RESUMO

Dengue virus (DENV) infection is a major cause of morbidity and mortality in Vietnam, and the incidence is higher and more consistent in the southern part of the country. This study investigated the circulation of DENV serotypes, viremia levels, immunological status, and cytokine levels, with disease severities among children infected in 2017 in Ho Chi Minh City, Southern Vietnam. Acute and convalescent serum samples were collected from clinically diagnosed dengue children. They were confirmed to have DENV infection by NS1 antigen, IgM and IgG ELISAs, virus isolation, and conventional and real-time RT-PCR. Measurement of 10 cytokine levels was performed in the serum samples. All the children were dengue IgM positive; 28% and 72% of them had primary and secondary DENV infections, respectively, whereas 54% of those with secondary infection were children with dengue with warning signs and with severe dengue. Any or mixed infection of the four serotypes of DENV RNA was detected in 58 children. Twenty DENV strains (DENV-1 = 16 and DENV-4 = 4) were isolated. Levels of IFN-γ, TNF-α, MCP-1, IL-10, and IL-6 were significantly higher in severe dengue cases. We report the predominance of DENV-1 over other serotypes in the 2017 dengue outbreak in Southern Vietnam. Our data showed that cytokine expressions were correlated with dengue pathogenesis and may help in identifying an effective therapeutic strategy.


Assuntos
Citocinas/sangue , Dengue/sangue , Dengue/epidemiologia , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Dengue/metabolismo , Dengue/patologia , Surtos de Doenças , Feminino , Regulação da Expressão Gênica , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Masculino , Estudos Retrospectivos , Vietnã/epidemiologia
11.
PLoS One ; 15(3): e0230337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32182271

RESUMO

BACKGROUND: Rapid tests detecting both dengue virus (DENV) NS1 antigen and anti-DENV IgM and IgG antibodies facilitate diagnosis of dengue fever (DF) in resource-poor settings. METHODOLOGY/PRINCIPAL FINDINGS: 92 acute phase serum samples from patients with a PCR-confirmed DENV infection collected in Lao People's Democratic Republic (Lao PDR) in 2013 and 2015 were analyzed with the SD Bioline Dengue Duo test. A subset of 74 samples was additionally tested with the Platelia NS1 antigen test, the Panbio DENV µ-capture ELISA and the Panbio DENV IgG ELISA. IgM seroconversion was assayed using follow-up samples of 35 patients collected in the convalescent phase. 57.6%, 22.8% and 44.6% of acute phase serum samples tested positive in the SD Bioline Dengue Duo NS1, IgM, and IgG test, respectively. Diagnostic sensitivity of the SD Bioline Dengue Duo NS1 test strongly correlated with viral load, decreased rapidly over the acute phase of the disease, and was significantly reduced in presence of high anti-DENV IgG antibody titers resulting from secondary DENV infection. While a good concordance (Cohen's kappa 0.78) was found between the SD Bioline Dengue Duo NS1 test and the Platelia NS1 antigen ELISA, both the SD Bioline Dengue Duo IgM and IgG test displayed a significantly lower sensitivity than the corresponding ELISA tests. CONCLUSIONS/SIGNIFICANCE: The SD Bioline Dengue Duo test is a valuable tool for diagnosis of DENV infections especially when analyzing early acute phase samples with high viral load. Nevertheless, in endemic areas, where secondary flavivirus infections are common, diagnostic sensitivity of the NS1 and IgM test components may be compromised.


Assuntos
Coinfecção/diagnóstico , Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Kit de Reagentes para Diagnóstico , Adolescente , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , Coinfecção/sangue , Coinfecção/imunologia , Coinfecção/virologia , Dengue/sangue , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulina M/isolamento & purificação , Laos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Soroconversão , Carga Viral , Proteínas não Estruturais Virais/sangue , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/isolamento & purificação , Adulto Jovem
12.
Immunology ; 160(1): 90-102, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32128816

RESUMO

Multifunctional interleukin 10 (IL10)+ Th1 cells have been implicated in favorable evolution of many infectious diseases, promoting an efficacious immune response while limiting immunopathology. Here, we investigated the presence of multifunctional CD4+ and CD8+ T-cells that expressed interferon gamma (IFNγ), IL10 and tumor necrosis factor (TNF), or its combinations during dengue infection. Peripheral blood mononuclear cells (PBMCs) from outpatients with dengue (mild dengue forms) and hospitalized patients (or patients with dengue with warning signs and severe dengue) were cultured in the presence of envelope (ENV) or NS3 peptide libraries of DENV during critical (hospitalization period) and convalescence phases. The production of IFNγ, IL10 and TNF by CD4+ and CD8+ T-cells was assessed by flow cytometry. Our data show that patients with mild dengue, when compared with patients with dengue with warning signs and severe dengue, presented higher frequencies of multifunctional T-cells like NS3-specific IFNγ/IL10-producing CD4+ T-cells in critical phase and NS3- and ENV-specific CD8+ T-cells producing IFNγ/IL10. In addition, NS3-specific CD8+ T-cells producing high levels of IFNγ/TNF and IFNγ/TNF/IL10 were also observed in the mild dengue group. We observed that multifunctional T-cells produced higher levels of cytokines as measured by intracellular content when compared with single producer T-cells. Importantly, multifunctional CD4+ and CD8+ T-cells producing IFNγ, TNF and IL10 simultaneously displayed positive correlation with platelet levels, suggesting a protective role of this population. The presence of IL10+ Th1 and IL10+ Tc1 multifunctional cells was associated with mild dengue presentation, suggesting that these cells play a role in clinical evolution of dengue infection.


Assuntos
Dengue/diagnóstico , Dengue/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Antígenos Virais/imunologia , Brasil , Estudos de Casos e Controles , Dengue/sangue , Vírus da Dengue/imunologia , Feminino , Voluntários Saudáveis , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , RNA Helicases/imunologia , Serina Endopeptidases/imunologia , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteínas não Estruturais Virais/imunologia , Adulto Jovem
13.
BMC Res Notes ; 13(1): 67, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041646

RESUMO

OBJECTIVE: To evaluate the frequency of infection caused by the Oropouche virus (OROV) in 496 patients with acute febrile disease (AFI), whose samples were obtained for the analysis of endemic arboviruses in a previous investigation carried out in 2016. RESULTS: OROV was detected in 26.4% (131/496) of serum samples from patients with AFI. Co-infections with Dengue virus (7.3%), Zika virus (1.8%) and Chikungunya (0.2%) were observed. The most common clinical symptoms reported among the patients with OROV infections were headache 85.5% (112/131), myalgia 80.9% (106/131), arthralgia 72.5% (95/131) and loss of appetite 67.9% (89/131). Headache and myalgia were predominant in all age groups. Both OROV infections and co-infections were more frequent in May, June and July corresponding to the dry season of the region.


Assuntos
Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/fisiopatologia , Febre de Chikungunya/epidemiologia , Coinfecção , Dengue/epidemiologia , Orthobunyavirus/patogenicidade , Infecção por Zika virus/epidemiologia , Adolescente , Adulto , Idoso , Infecções por Bunyaviridae/sangue , Infecções por Bunyaviridae/complicações , Febre de Chikungunya/sangue , Criança , Pré-Escolar , Comorbidade , Dengue/sangue , Feminino , Febre/epidemiologia , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Adulto Jovem , Infecção por Zika virus/sangue
14.
Ann Palliat Med ; 9(1): 70-81, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32005065

RESUMO

BACKGROUND: In 2014, a serious dengue outbreak occurred in Guangzhou, South China. In this study, the clinical and laboratory characteristics of dengue fever (DF) group and other febrile illnesses (OFI) group in Guangzhou were described. METHODS: Clinical and laboratory data collected by studying 1,792 patients from Nanfang Hospital, Southern Medical University during 2014 and 2018. Laboratory data was analyzed by SPSS 22.0 statistical software including Full blood counts (SYSMEX XE-5000), Laboratory Biochemical tests (Roche Cobas 8000), Dengue virus RNA (RT-PCR-Fluorescence Probing) and Dengue IgG/IgM Antibody (Colloidal Gold), Dengue Virus NS1 (ELISA). RESULTS: In the DF group and OFI group, gender ratios were 1.08:1 (male/female, P>0.05) and 1.45:1 (male/female, P<0.05). Adults aged 25-34 years old (29.4%) with the main peak appeared in the DF group, and the same main peak appeared in the OFI group: 25-34 years old (25.13%). Patients were from Medical emergency (41.2% DF group, 29.4% OFI group). The distribution of fever days before treatment was mainly focused within 5 days, with a main peak in the 2 fever days before treatment (24.6%) in the DF group and the main peak in 1 fever day before treatment (46.9%) in OFI group. The major symptoms of the DF group were presented with were fever (100%), myalgia (34.77%), pharyngeal hyperemia (31.33%), headache (25.65%), adenoids (19.62%), and rash (13.25%). In the OFI group, Pharyngeal hyperemia was the most common clinical symptom, accounting for 27.24%, and the next symptom was adenoids (21.26%). The sensitivity and specificity of DV RNA were 61.54%, 100%, respectively, compared to the DF Nonstructural protein 1 (NS1). Dengue virus (DENV) Immunoglobulin M (IgM) IgM in both groups was statistically significant, with DENV-IgM in the DF group were stronger (Z=-7.863, P<0.001), and DENV immunoglobulin G (IgG) were no statistically significant (Z=-1.212, P=0.226). In DF group, 37.14% of serum samples had elevated Alanine transaminase (ALT) levels, 76.85% of them had elevated aspartate aminotransferase (AST) levels, 32.08% of them had elevated creatine kinase (CK) levels, and 2.67% of them had elevated C-reaction protein (CRP) levels, compared with 13.51% of them had elevated ALT levels, 30.65% of them had elevated AST levels, 6.06% of them had elevated CK levels and 69.35% of them had elevated CRP levels of the OFI patients. The prominent manifestations were thrombocytopenia (occurring in 28.07% of the DF group, compared to 5.18% of OFI group) and leucopenia (occurring in 43.27% of DF group and 3.63% of OFI group). The DF incidence of all fever cases was 49.0% within three months in 2014, compared with 1.4% in 2015, 0% in 2016, 0.9% in 2017 and 6.4% in 2018 (P<0.001). DF and OFI can occur in any age and sex. DF occurred in the young and the old, OFI occurred in children and youth. The clinical symptoms of myalgia, headache, rash, weak, Chills, follicular hyperplasia in both groups were statistically significant (P<0.001). CONCLUSIONS: IgM can be easily recognized for early diagnoses, DENV-RNA had lower sensitivity and higher specificity, and DF NS1 enzyme-linked immunosorbent assay (ELISA) has a higher sensitive and specificity. DF is a serious public health problem and an emerging continuous threat in Guangzhou. In high-prevalence areas, effective epidemic monitoring and prevention measures need to be undertaken. After the unprecedented outbreak in 2014, on account of the government and citizen paying more attention to the DF epidemic, the cases of DF were decreased significantly from 2015 to 2018.


Assuntos
Dengue/patologia , Surtos de Doenças , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Dengue/sangue , Dengue/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lactente , Masculino , Sensibilidade e Especificidade , Inquéritos e Questionários , Adulto Jovem
15.
Am J Trop Med Hyg ; 102(3): 622-624, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31933466

RESUMO

Laboratory-based surveillance for arboviral diseases is challenging in resource-limited settings. We evaluated the use of filter paper-dried sera for detection of dengue virus (DENV) RNA during an outbreak in American Samoa. Matched liquid and filter paper-dried sera were collected from patients with suspected dengue and shipped to a reference laboratory for diagnostic testing. RNA was extracted from each sample and tested for DENV RNA by real-time reverse transcription-polymerase chain reaction (RT-PCR). Of 18 RT-PCR-positive liquid specimens, 14 matched filter paper-dried specimens were positive for a sensitivity of 78% (95% CI, 55-91%). Of 82 RT-PCR-negative liquid specimens, all filter paper-dried specimens were negative for a specificity of 100% (95% CI, 96-100%). Shipping of filter paper-dried specimens was similarly timely but less expensive than shipping liquid sera. Using filter paper-dried serum or blood can be a cost-effective and sustainable approach to surveillance of dengue and other arboviral diseases in resource-limited settings.


Assuntos
Dengue/sangue , Dengue/diagnóstico , Vigilância da População , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Testes Sorológicos/métodos , Samoa Americana , Dengue/epidemiologia , Humanos , Sensibilidade e Especificidade , Soro
16.
Biosens Bioelectron ; 151: 111972, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31999580

RESUMO

Dengue non-structural protein 1 (NS1 DENV) is considered a biomarker for dengue fever in an early stage. A sensitive and rapid assay for distinguishing positive from negative dengue infection samples is imperative for epidemic control and public health in tropical regions because it enables the development of instantaneous updatable databases and effective surveillance systems. Presently, we successfully report, for the first time, the use of the electrochemical capacitive method for the detection of NS1 DENV biomarker in human serum samples. By using a ferrocene-tagged peptide modified surface containing anti-NS1 as the receptor, it was possible to differentiate positive from negative samples with a p < 0.01 in a reagentless and label-free capacitive format. This capacitive assay had a cut-off of 1.36% (confidence interval of 99.99%); it therefore opens new avenues for developing miniature label-free electrochemical devices for infectious diseases.


Assuntos
Técnicas Biossensoriais , Vírus da Dengue/isolamento & purificação , Dengue/sangue , Proteínas não Estruturais Virais/sangue , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/sangue , Antígenos Virais/imunologia , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Proteínas não Estruturais Virais/imunologia
17.
J Infect Dis ; 221(1): 91-101, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31428794

RESUMO

BACKGROUND: Micronutrients are known to modulate host immunity, and there is limited literature on this association in the context of dengue virus infection (DENV). METHODS: Using a nested case-control design in a surveillance program, we measured the following: anthropometry; nutritional biomarkers including serum ferritin, soluble transferrin receptor, retinol-binding protein (RBP), 25-hydroxy vitamin D, folate, and vitamin B12; and a panel of immune response markers. We then compared these measures across 4 illness categories: healthy control, nonfebrile DENV, other febrile illness (OFI), and apparent DENV using multivariate polytomous logistic regression models. RESULTS: Among 142 participants, serum ferritin (ng/mL) was associated with apparent DENV compared to healthy controls (odds ratio [OR], 2.66; confidence interval [CI], 1.53-4.62; P = .001), and RBP concentrations (µmol/L) were associated with apparent DENV (OR, 0.03; CI, 0.00-0.30; P = .003) and OFI (OR, 0.02; CI, 0.00-0.24; P = .003). In a subset of 71 participants, interleukin-15 levels (median fluorescent intensity) were positively associated with apparent DENV (OR, 1.09; CI, 1.03-1.14; P = .001) and negatively associated with nonfebrile DENV (OR, 0.89; CI, 0.80-0.99; P = .03) compared to healthy controls. CONCLUSIONS: After adjusting for the acute-phase response, serum ferritin and RBP concentrations were associated with apparent DENV and may represent biomarkers of clinical importance in the context of dengue illness.


Assuntos
Dengue/sangue , Dengue/imunologia , Interleucina-15/sangue , Vigilância da População , Adolescente , Biomarcadores/sangue , Índice de Massa Corporal , Tamanho Corporal , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Equador , Feminino , Ferritinas/sangue , Febre/sangue , Febre/virologia , Humanos , Masculino , Micronutrientes , Estado Nutricional , Orosomucoide/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Vitamina D/sangue , Adulto Jovem
18.
J Microbiol Immunol Infect ; 53(1): 157-162, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31029530

RESUMO

BACKGROUND: Human leptospirosis, or commonly known as "rat urine disease" is a zoonotic disease that is caused by the bacteria called Leptospira sp. The incidence rate of leptospirosis has been under-reported due to its unspecific clinical symptoms and the limitations of current laboratory diagnostic methods. Leptospirosis can be effectively treated with antibiotics in the early stage, and it is a curable disease but the accuracy to diagnose the infection is rarely achieved. METHODS: The present pilot study investigated plasma protein profiles of leptospirosis patients and compared them against two control groups which consisted of dengue patients and healthy individuals. The plasma protein digests were analyzed using shotgun approach by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Protein abundances were estimated from the exponentially modified protein abundance index (emPAI) values. Plasma proteins in leptospirosis patients with at least two-fold differential expression compared to dengue and healthy control groups (p < 0.05, ANOVA) were identified. RESULTS: Lipopolysaccharide (LPS)-binding protein (LBP) was found to be the only protein that has significant different expression between leptospirosis and the two control groups. The expression levels of leucine-rich alpha-2-glycoprotein (LRG1) and alpha-1-antichymotrypsin (ACT) were different significantly between leptospirosis and healthy group but not to the dengue control group. CONCLUSION: This is the first plasma proteome-based study on leptospirosis that reports the differential expression of LBP compared to both dengue and healthy controls, which has not been previously reported in the context of leptospirosis.


Assuntos
Proteínas da Fase Aguda/genética , Proteínas de Transporte/sangue , Proteínas de Transporte/genética , Leptospirose/sangue , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/genética , Proteoma/análise , Adolescente , Adulto , Cromatografia Líquida , Dengue/sangue , Humanos , Projetos Piloto , Proteômica , Espectrometria de Massas em Tandem , Adulto Jovem
19.
Transfus Med ; 30(1): 37-45, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31709647

RESUMO

OBJECTIVES: Our study aimed to update the seroprevalence and factors associated with anti-dengue virus (DENV) antibody positivity among blood donors and to discuss their implications for blood supply. BACKGROUND: Questions on the potential transmission of DENV by transfusion increased after the documentation of the risk of transmission of the West Nile virus. This risk was estimated after transfusion of DENV RNA-positive blood units of up to 37.5%. In Burkina Faso, very few studies on DENV in blood donors have been conducted. As a result, there were no reliable data on DENV to allow the implementation of appropriate measures to control the risk of transmission of the dengue virus by blood transfusion. METHODS: We conducted a 4-week cross-sectional study from December 4 to 30, 2016. Blood donors of both genders, aged 18-60 years, accepted for blood donation after medical selection were consecutively enrolled. RESULTS: Our study included a total of 1007 blood donors, in which donors living in urban areas represented 78.2%. The mean age was 26.1 ± 8.1 years. After adjustment in a multiple regression logistic model, the odds of having IgG anti-DENV increased as age increased. The odds of DENV was 53% lower in rural areas (OR = 0.47; P = .000) compared to urban settings and 42% lower in mobile sites (OR = 0.58; P = .03) compared to fixed ones. CONCLUSION: Our study provides new and useful insights for future research on the risk of TT-DENV throughout blood transfusion.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Segurança do Sangue , Vírus da Dengue/metabolismo , Dengue , Surtos de Doenças , Adolescente , Adulto , Burkina Faso , Estudos Transversais , Dengue/sangue , Dengue/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos
20.
Diagn Microbiol Infect Dis ; 96(3): 114918, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31839333

RESUMO

We assessed a dengue IgG rapid diagnostic test (RDT) and IgG enzyme-linked immunosorbent assay (ELISA) to determine their suitability for dengue prevaccination screening. Each exhibited ≥99% specificity. The RDT demonstrated no Zika cross-reactivity, while the ELISA displayed greater sensitivity. Both could safely guide vaccination in Puerto Rico pending availability of improved serotests.


Assuntos
Anticorpos Antivirais/sangue , Dengue/diagnóstico , Ensaio de Imunoadsorção Enzimática , Testes Sorológicos/métodos , Ensaios Clínicos como Assunto , Reações Cruzadas/imunologia , Dengue/sangue , Dengue/imunologia , Vacinas contra Dengue/administração & dosagem , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Porto Rico , Sensibilidade e Especificidade , Vacinação/estatística & dados numéricos , Infecção por Zika virus/diagnóstico
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