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1.
Braz J Infect Dis ; 24(5): 405-411, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941805

RESUMO

Several major epidemics of Zika fever, caused by the ZIKA virus (ZIKV), have emerged in Brazil since early 2015, eventually spreading to other countries on the South American continent. The present study describes the clinical manifestations and laboratory findings of patients with confirmed acute ZIKV infection during the first epidemic that occurred in Salvador, Brazil. All included patients were seen at the emergency room of a private tertiary hospital located in Salvador, Brazil from 2015 through 2017. Patients were considered eligible if signs of systemic viral febrile disease were present. All individuals were tested for ZIKV and Chikungunya infection using PCR, while rapid test was used to detect Dengue virus antibodies or, alternatively, the NS1 antigen. A diagnosis of acute ZIKV infection was confirmed in 78/434 (18%) individuals with systemic viral febrile illness. Positivity was mainly observed in blood, followed by saliva and urine. Coinfection with Chikungunya and/or Dengue virus was detected in 5% of the ZIKV-infected patients. The most frequent clinical findings were myalgia, arthralgia and low-grade fever. Laboratory analysis demonstrated normal levels of hematocrit, platelets and liver enzymes. In summary, in acute settings where molecular testing remains unavailable, clinicians face difficulties to confirm the diagnosis of ZIKV infection, as they rely only on clinical examinations and conventional laboratory tests.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Vírus da Dengue , Dengue , Epidemias , Infecção por Zika virus , Zika virus , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Dengue/epidemiologia , Humanos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
2.
Rev Prat ; 70(3): 336-340, 2020 Mar.
Artigo em Francês | MEDLINE | ID: mdl-32877073

RESUMO

Chikungunya. Chikungunya is a cosmopolitan arbovirosis transmitted by a mosquito of the genus Aedes. It is characterized by the possible persistence of musculoskeletal symptoms more than three months after infection. After inoculation by an infected mosquito and incubation for three days, the infection is symptomatic in 75-95% of cases. There are three stages. The acute stage is characterized by the sudden onset of high fever associated with incapacitating distal polyarthralgia. Atypical, sometimes severe, manifestations are possible: neurological, digestive, cardiac, hepatic, dermatological, hematological, pulmonary and renal. These atypical forms are most often observed at extreme ages and in people with chronic diseases. The post-acute stage (60-80% of cases, from the fourth week to the end of the third month) is characterized by persistent and polymorphic musculoskeletal manifestations. During the chronic stage (50% of cases from the fourth month onwards) two entities can be distinguished: chronic inflammatory rheumatism and musculoskeletal disorders. Management is symptomatic. It is based on a precise semiological analysis, attentive listening to the patient and a multidisciplinary approach.


Assuntos
Aedes , Artrite Reumatoide , Febre de Chikungunya , Vírus Chikungunya , Animais , Febre de Chikungunya/complicações , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/transmissão , Doença Crônica , Humanos
3.
Nat Commun ; 11(1): 4693, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943634

RESUMO

The alphavirus capsid protein (Cp) selectively packages genomic RNA (gRNA) into the viral nucleocapsid to produce infectious virus. Using photoactivatable ribonucleoside crosslinking and an innovative biotinylated Cp retrieval method, here we comprehensively define binding sites for Semliki Forest virus (SFV) Cp on the gRNA. While data in infected cells demonstrate Cp binding to the proposed genome packaging signal (PS), mutagenesis experiments show that PS is not required for production of infectious SFV or Chikungunya virus. Instead, we identify multiple Cp binding sites that are enriched on gRNA-specific regions and promote infectious SFV production and gRNA packaging. Comparisons of binding sites in cytoplasmic vs. viral nucleocapsids demonstrate that budding causes discrete changes in Cp-gRNA interactions. Notably, Cp's top binding site is maintained throughout virus assembly, and specifically binds and assembles with Cp into core-like particles in vitro. Together our data suggest a model for selective alphavirus genome recognition and assembly.


Assuntos
Alphavirus/metabolismo , Proteínas do Capsídeo/metabolismo , Capsídeo/metabolismo , Genômica , RNA Viral/genética , Alphavirus/genética , Alphavirus/ultraestrutura , Animais , Sítios de Ligação , Capsídeo/química , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Vírus Chikungunya/genética , Chlorocebus aethiops , Modelos Moleculares , Nucleocapsídeo/metabolismo , Ligação Proteica , RNA Viral/química , Vírus da Floresta de Semliki/metabolismo , Células Vero , Montagem de Vírus , Replicação Viral
5.
PLoS Negl Trop Dis ; 14(9): e0008549, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881913

RESUMO

BACKGROUND: Chikungunya (CHIK) and yellow fever (YF) are becoming major public health threats in East African countries including Ethiopia. In Ethiopia, there is no reliable information about the epidemiology of CHIK. This study aimed to assess a community-based sero-prevalence of CHIK and YF in the South Omo Valley, an endemic area for YF. METHODS: Between February and June 2018, blood samples were collected from study participants and screened for IgG antibody against CHIK virus (CHIKV) and YF virus (YFV) infections using ELISA. Data were computerized using Epi Data Software v.3.1 and analyzed using SPSS. RESULTS: A total of 360 participants (51.7% males, age range from 6 to 80, mean age ± SD = 31.95 ± 14.05 years) participated in this study. The overall sero-prevalence of IgG antibody was 43.6% (157/360) against CHIKV, while it was 49.5% (155/313) against YFV. Out of 155 samples which were positive for IgG antibody to YFV, 93 (60.0%) were positive for IgG antibody to CHIKV. Out of 158 samples which were negative for IgG antibody to YFV, 64(40.5%) were positive for IgG antibody to CHIKV. There was a significant positive correlation between IgG antibodies to CHIKV and YFV (sr = 0.82; P<0.01). Residency in the Debub Ari district (AOR = 8.47; 95% CI: 1.50, 47.74) and travel history to sylvatic areas (AOR = 2.21; 95% CI: 1.02, 4.81) were significantly and positively associated with high sero-prevalence of IgG antibody to CHIKV and YFV, respectively. CONCLUSION: High sero-prevalence of IgG antibody to CHIKV shows the circulation of the virus in the present study area. A low sero-prevalence of IgG antibody to YFV in YF vaccine received individuals is highly concerning from a public health point of view as waning of immune response to YFV infection could result in a periodic outbreaks of YF in endemic areas.Nevertheless, the present study has not investigated for possible cross-reactivity of antibody to CHIKV with other alphaviruses like O'nyong-nyong virus and antibody to YFV with other flaviviruses like Dengue fever virus and this warrants further studies in the present study area.


Assuntos
Anticorpos Antivirais/sangue , Febre de Chikungunya/sangue , Febre Amarela/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/imunologia , Vírus Chikungunya/isolamento & purificação , Criança , Estudos Transversais , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Características de Residência , Estudos Soroepidemiológicos , Febre Amarela/epidemiologia , Febre Amarela/virologia , Vírus da Febre Amarela/imunologia , Vírus da Febre Amarela/isolamento & purificação , Adulto Jovem
8.
PLoS Negl Trop Dis ; 14(8): e0008469, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32764759

RESUMO

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus, which has rapidly spread around the globe thereby causing millions of infections. CHIKV is an enveloped virus belonging to the Togaviridae family and enters its host cell primarily via clathrin-mediated endocytosis. Upon internalization, the endocytic vesicle containing the virus particle moves through the cell and delivers the virus to early endosomes where membrane fusion is observed. Thereafter, the nucleocapsid dissociates and the viral RNA is translated into proteins. In this study, we examined the importance of the microtubule network during the early steps of infection and dissected the intracellular trafficking behavior of CHIKV particles during cell entry. We observed two distinct CHIKV intracellular trafficking patterns prior to membrane hemifusion. Whereas half of the CHIKV virions remained static during cell entry and fused in the cell periphery, the other half showed fast-directed microtubule-dependent movement prior to delivery to Rab5-positive early endosomes and predominantly fused in the perinuclear region of the cell. Disruption of the microtubule network reduced the number of infected cells. At these conditions, membrane hemifusion activity was not affected yet fusion was restricted to the cell periphery. Furthermore, follow-up experiments revealed that disruption of the microtubule network impairs the delivery of the viral genome to the cell cytosol. We therefore hypothesize that microtubules may direct the particle to a cellular location that is beneficial for establishing infection or aids in nucleocapsid uncoating.


Assuntos
Vírus Chikungunya/fisiologia , Genoma Viral , Microtúbulos/fisiologia , Replicação Viral/fisiologia , Animais , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Humanos , Nocodazol/farmacologia , Moduladores de Tubulina/farmacologia
9.
PLoS One ; 15(8): e0238254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841293

RESUMO

The identification of host / pathogen interactions is essential to both understanding the molecular biology of infection and developing rational intervention strategies to overcome disease. Alphaviruses, such as Sindbis virus, Chikungunya virus, and Venezuelan Equine Encephalitis virus are medically relevant positive-sense RNA viruses. As such, they must interface with the host machinery to complete their infectious lifecycles. Nonetheless, exhaustive RNA:Protein interaction discovery approaches have not been reported for any alphavirus species. Thus, the breadth and evolutionary conservation of host interactions on alphaviral RNA function remains a critical gap in the field. Herein we describe the application of the Cross-Link Assisted mRNP Purification (CLAMP) strategy to identify conserved alphaviral interactions. Through comparative analyses, conserved alphaviral host / pathogen interactions were identified. Approximately 100 unique host proteins were identified as a result of these analyses. Ontological assessments reveal enriched Molecular Functions and Biological Processes relevant to alphaviral infection. Specifically, as anticipated, Poly(A) RNA Binding proteins are significantly enriched in virus specific CLAMP data sets. Moreover, host proteins involved in the regulation of mRNA stability, proteasome mediated degradation, and a number of 14-3-3 proteins were identified. Importantly, these data expand the understanding of alphaviral host / pathogen interactions by identifying conserved interactants.


Assuntos
Alphavirus/genética , Alphavirus/patogenicidade , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Proteínas de Ligação a Poli(A)/genética , Proteínas de Ligação a Poli(A)/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Alphavirus/fisiologia , Animais , Linhagem Celular , Vírus Chikungunya/genética , Vírus Chikungunya/patogenicidade , Vírus Chikungunya/fisiologia , Vírus da Encefalite Equina Venezuelana/genética , Vírus da Encefalite Equina Venezuelana/patogenicidade , Vírus da Encefalite Equina Venezuelana/fisiologia , Evolução Molecular , Células HEK293 , Humanos , Mapas de Interação de Proteínas , Ribonucleoproteínas/genética , Ribonucleoproteínas/isolamento & purificação , Ribonucleoproteínas/metabolismo , Vírus Sindbis/genética , Vírus Sindbis/patogenicidade , Vírus Sindbis/fisiologia , Especificidade da Espécie
10.
Virology ; 548: 250-260, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32791353

RESUMO

Chikungunya has re-emerged as an epidemic with global distribution and high morbidity, necessitating the need for effective therapeutics. We utilized already approved drugs with a good safety profile used in other diseases for their new property of anti-chikungunya activity. It provides a base for a fast and efficient approach to bring a novel therapy from bench to bedside by the process of drug-repositioning. We utilized an in-silico drug screening with FDA approved molecule library to identify inhibitors of the chikungunya nsP2 protease, a multifunctional and essential non-structural protein required for virus replication. Telmisartan, an anti-hypertension drug, and the antibiotic novobiocin emerged among top hits on the screen. Further, SPR experiments revealed strong in-vitro binding of telmisartan and novobiocin to nsP2 protein. Additionally, small angle x-ray scattering suggested binding of molecules to nsP2 and post-binding compaction and retention of monomeric state in the protein-inhibitor complex. Protease activity measurement revealed that both compounds inhibited nsP2 protease activity with IC50 values in the low micromolar range. More importantly, plaque formation assays could show the effectiveness of these drugs in suppressing virus propagation in host cells. We propose novobiocin and telmisartan as potential inhibitors of chikungunya replication. Further research is required to establish the molecules as antivirals of clinical relevance against chikungunya.


Assuntos
Antivirais/farmacologia , Febre de Chikungunya/virologia , Vírus Chikungunya/efeitos dos fármacos , Novobiocina/farmacologia , Telmisartan/farmacologia , Febre de Chikungunya/tratamento farmacológico , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
11.
PLoS Pathog ; 16(8): e1008754, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776975

RESUMO

Arbovirus infection of Aedes aegypti salivary glands (SGs) determines transmission. However, there is a dearth of knowledge on SG immunity. Here, we characterized SG immune response to dengue, Zika and chikungunya viruses using high-throughput transcriptomics. We also describe a transcriptomic response associated to apoptosis, blood-feeding and lipid metabolism. The three viruses differentially regulate components of Toll, Immune deficiency (IMD) and c-Jun N- terminal Kinase (JNK) pathways. However, silencing of the Toll and IMD pathway components showed variable effects on SG infection by each virus. In contrast, regulation of the JNK pathway produced consistent responses in both SGs and midgut. Infection by the three viruses increased with depletion of the activator Kayak and decreased with depletion of the negative regulator Puckered. Virus-induced JNK pathway regulates the complement factor, Thioester containing protein-20 (TEP20), and the apoptosis activator, Dronc, in SGs. Individual and co-silencing of these genes demonstrate their antiviral effects and that both may function together. Co-silencing either TEP20 or Dronc with Puckered annihilates JNK pathway antiviral effect. Upon infection in SGs, TEP20 induces antimicrobial peptides (AMPs), while Dronc is required for apoptosis independently of TEP20. In conclusion, we revealed the broad antiviral function of JNK pathway in SGs and showed that it is mediated by a TEP20 complement and Dronc-induced apoptosis response. These results expand our understanding of the immune arsenal that blocks arbovirus transmission.


Assuntos
Aedes/imunologia , Apoptose , Febre de Chikungunya/imunologia , Proteínas do Sistema Complemento/imunologia , Dengue/imunologia , Sistema de Sinalização das MAP Quinases , Glândulas Salivares/imunologia , Infecção por Zika virus/imunologia , Aedes/virologia , Animais , Febre de Chikungunya/metabolismo , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/virologia , Vírus Chikungunya/imunologia , Proteínas do Sistema Complemento/metabolismo , Dengue/metabolismo , Dengue/prevenção & controle , Dengue/virologia , Vírus da Dengue/imunologia , Feminino , Interações Hospedeiro-Patógeno , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Insetos Vetores/imunologia , Insetos Vetores/virologia , Glândulas Salivares/virologia , Transcriptoma , Replicação Viral , Zika virus/imunologia , Infecção por Zika virus/metabolismo , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/virologia
13.
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
14.
PLoS Negl Trop Dis ; 14(6): e0008135, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603322

RESUMO

Mosquitoes are vectors of viruses affecting animal and human health. In Iran, the prevalence of mosquito-borne viruses remains poorly investigated. Once infected, mosquito females remain infected for all their life making virus detections possible at early steps before infections are reported in vertebrate hosts. In this study, we used a recently developed high-throughput chip based on the BioMark Dynamic arrays system capable of detecting 37 arboviruses in a single experiment. A total of 1,212 mosquitoes collected in Mazandaran, North-Khorasan, and Fars provinces of Iran were analyzed. Eighteen species were identified, belonging to five genera; the most prevalent species were Anopheles maculipennis s.l. (42.41%), Culex pipiens (19.39%), An. superpictus (11.72%), and Cx. tritaeniorhynchus (10.64%). We detected chikungunya virus (CHIKV) of the Asian genotype in six mosquito pools collected in North Khorasan and Mazandaran provinces. To our knowledge, this is the first report of mosquitoes infected with CHIKV in Iran. Our high-throughput screening method can be proposed as a novel epidemiological surveillance tool to identify circulating arboviruses and to support preparedness to an epidemic in animals and humans.


Assuntos
Vírus Chikungunya/isolamento & purificação , Culicidae/virologia , Animais , Culicidae/classificação , Feminino , Irã (Geográfico) , Masculino
15.
PLoS One ; 15(7): e0234959, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663230

RESUMO

The economic and social impacts due to diseases transmitted by mosquitoes in the latest years have been significant. Currently, no specific treatment or commercial vaccine exists for the control and prevention of arboviruses, thereby making entomological characterization fundamental in combating diseases such as dengue, chikungunya, and Zika. The morphological identification of mosquitos includes a visual exam of the samples. It is time consuming and requires adequately trained professionals. Accordingly, the development of a new automated method for realizing mosquito-perception and -classification is becoming increasingly essential. Therefore, in this study, a computational model based on a convolutional neural network (CNN) was developed to extract features from the images of mosquitoes and then classify the species Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus. In addition, the model was trained to detect the mosquitoes of the genus Aedes. To train CNNs to perform the automatic morphological classification of mosquitoes, a dataset, which included 7,561 images of the target mosquitoes and 1,187 images of other insects, was acquired. Various neural networks, such as Xception and DenseNet, were used for developing the automatic-classification model based on images. A structured optimization process of random search and grid search was developed to select the hyperparameters set and increase the accuracy of the model. In addition, strategies to eliminate overfitting were implemented to increase the generalization of the model. The optimized model, during the test phase, obtained the balanced accuracy (BA) of 93.5% in classifying the target mosquitoes and other insects and the BA of 97.3% in detecting the mosquitoes of the genus Aedes in comparison to Culex. The results provide fundamental information for performing the automatic morphological classification of mosquito species. Using a CNN-embedded entomological tool is a valuable and accessible resource for health workers and non-taxonomists for identifying insects that can transmit infectious diseases.


Assuntos
Arbovirus/classificação , Culicidae/classificação , Processamento de Imagem Assistida por Computador/métodos , Aedes/virologia , Animais , Automação Laboratorial/métodos , Febre de Chikungunya/transmissão , Vírus Chikungunya/genética , Culex/virologia , Culicidae/genética , Dengue/transmissão , Vírus da Dengue/genética , Feminino , Masculino , Mosquitos Vetores/virologia , Zika virus/genética , Infecção por Zika virus/transmissão
16.
Viruses ; 12(7)2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635194

RESUMO

Chikungunya virus (CHIKV) is an enveloped virus that enters host cells and transits within the endosomes before starting its replication cycle, the precise mechanism of which is yet to be elucidated. Endocytosis and endosome acidification inhibitors inhibit infection by CHIKV, murine leukemia virus (MLV), or SARS-coronavirus, indicating that these viral entries into host cells occur through endosomes and require endosome acidification. Although endosomal cathepsin B protease is necessary for MLV, Ebola virus, and SARS-CoV infections, its role in CHIKV infection is unknown. Our results revealed that endocytosis inhibitors attenuated CHIKV-pseudotyped MLV vector infection in 293T cells but not in TE671 cells. In contrast, macropinocytosis inhibitors attenuated CHIKV-pseudotyped MLV vector infection in TE671 cells but not in 293T cells, suggesting that CHIKV host cell entry occurs via endocytosis or macropinocytosis, depending on the cell lines used. Cathepsin B inhibitor and knockdown by an shRNA suppressed CHIKV-pseudotyped MLV vector infection both in 293T and TE671 cells. These results show that cathepsin B facilitates CHIKV infection regardless of the entry pathway.


Assuntos
Catepsina B/metabolismo , Febre de Chikungunya/patologia , Vírus Chikungunya/fisiologia , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus , Catepsina B/antagonistas & inibidores , Linhagem Celular Tumoral , Endocitose/fisiologia , Endossomos/virologia , Células HEK293 , Células HeLa , Humanos , Vírus da Leucemia Murina/fisiologia , Pinocitose/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética
17.
Am J Trop Med Hyg ; 103(4): 1660-1669, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32700661

RESUMO

Chikungunya fever is a viral mosquito-borne, acute febrile illness associated with rash, joint pain, and occasionally prolonged polyarthritis. Chikungunya outbreaks have been reported worldwide including many provinces of Thailand. Although chikungunya virus (CHIKV) occurs in Thailand, details on its epidemiology are lacking compared with dengue, a common mosquito-borne disease in the country. Therefore, study on CHIKV and its epidemiology in both humans and mosquitoes is required to better understand its importance clinically and dynamics in community settings. So a prospective examination of virus circulation in human and mosquito populations in northeastern Thailand using serological and molecular methods, including the genetic characterization of the virus, was undertaken. The study was conducted among febrile patients in eight district hospitals in northeastern Thailand from June 2016 to October 2017. Using real-time PCR on the conserved region of nonstructural protein 1 gene, CHIKV was detected in eight (4.9%) of 161 plasma samples. Only one strain yielded a sequence of sufficient size allowing for phylogenetic analysis. In addition, anti-CHIKV IgM and IgG were detected in six (3.7%) and 17 (10.6%) patient plasma samples. The single sequenced sample belonged to the East/Central/South Africa (ECSA) genotype and was phylogenetically similar to the Indian Ocean sub-lineage. Adult Aedes mosquitoes were collected indoors and within a 100-m radius from the index case house and four neighboring houses. CHIKV was detected in two of 70 (2.9%) female Aedes aegypti mosquito pools. This study clearly demonstrated the presence and local transmission of the ECSA genotype of CHIKV in the northeastern region of Thailand.


Assuntos
Aedes/virologia , Anticorpos Antivirais/sangue , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/imunologia , Surtos de Doenças , Mosquitos Vetores/virologia , Adolescente , Adulto , Idoso , Animais , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Prospectivos , Tailândia/epidemiologia , Adulto Jovem
18.
BMC Public Health ; 20(1): 947, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546159

RESUMO

INTRODUCTION: Chikungunya and Zika Virus are vector-borne diseases responsible for a substantial disease burden in the Americas. Between 2013 and 2016, no cases of Chikungunya or Zika Virus were reported by the Venezuelan Ministry of Health. However, peaks of undiagnosed fever cases have been observed during the same period. In the context of scarce data, alternative surveillance methods are needed. Assuming that unusual peaks of acute fever cases correspond to the incidences of both diseases, this study aims to evaluate the use of Google Trends as an indicator of the epidemic behavior of Chikungunya and Zika. METHODS: Time-series cross-correlations of acute fever cases reported by the Venezuelan Ministry of Health and data on Google search queries related to Chikungunya and Zika were calculated. RESULTS: A temporal distinction has been made so that acute febrile cases occurring between 25th of June 2014 and 23rd of April 2015 were attributed to the Chikungunya virus, while cases occurring between 30th of April 2015 and 29th of April 2016 were ascribed to the Zika virus. The highest cross-correlations for each disease were shown at a lag of 0 (r = 0.784) for Chikungunya and at + 1 (r = 0.754) for Zika. CONCLUSION: The strong positive correlation between Google search queries and official data on acute febrile cases suggests that this resource can be used as an indicator of endemic urban arboviruses activity. In the Venezuelan context, Internet search queries might help to overcome some of the gaps that exist in the national surveillance system.


Assuntos
Arbovirus , Febre de Chikungunya/epidemiologia , Febre/etiologia , Comportamento de Busca de Informação , Internet , Vigilância da População/métodos , Infecção por Zika virus/epidemiologia , Febre de Chikungunya/complicações , Febre de Chikungunya/virologia , Vírus Chikungunya , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue , Epidemias , Febre/virologia , Órgãos Governamentais , Humanos , Incidência , Ferramenta de Busca/tendências , População Urbana , Venezuela/epidemiologia , Zika virus , Infecção por Zika virus/complicações , Infecção por Zika virus/virologia
19.
Am J Trop Med Hyg ; 103(3): 1228-1233, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32588813

RESUMO

Zoonotic pathogens such as arboviruses have comprised a significant proportion of emerging infectious diseases in humans. The role of wildlife species as reservoirs for arboviruses is poorly understood, especially in endemic areas such as Southeast Asia. This study aims to determine the exposure history of different macaque species from national parks in Thailand to mosquito-borne flaviviruses and alphavirus by testing the serum samples collected from 25 northern pigtailed macaques, 33 stump-tailed macaques, and 4 long-tailed macaques for the presence of antibodies against dengue, Zika, and chikungunya viruses by plaque reduction neutralization assay. Specific neutralizing antibodies against Dengue virus (DENV1-4) and Zika virus (ZIKV) were mainly found in stump-tailed macaques, whereas neutralizing antibody titers were not detected in long-tailed macaques and pigtailed macaques as determined by 90% plaque reduction neutralization assay (PRNT90). One long-tailed macaque captured from the south of Thailand exhibited antibody titers against chikungunya virus (CHIKV), suggesting enzootic of this virus to nonhuman primates (NHPs) in Thailand. Encroachment of human settlements into the forest has increased the interface that exposes humans to zoonotic pathogens such as arboviruses found in monkeys. Nonhuman primates living in different regions of Thailand showed different patterns of arboviral infections. The presence of neutralizing antibodies among wild monkeys in Thailand strongly suggests the existence of sylvatic cycles for DENV, ZIKV, and CHIKV in Thailand. The transmission of dengue, Zika, and chikungunya viruses among wild macaques may have important public health implications.


Assuntos
Febre de Chikungunya/epidemiologia , Vírus Chikungunya/imunologia , Culicidae/virologia , Vírus da Dengue/imunologia , Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Zika virus/imunologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/sangue , Febre de Chikungunya/virologia , Dengue/virologia , Feminino , Geografia , Humanos , Macaca , Masculino , Mosquitos Vetores/virologia , Estudos Soroepidemiológicos , Tailândia/epidemiologia , Infecção por Zika virus/virologia
20.
PLoS One ; 15(6): e0234267, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32503031

RESUMO

Our objective was to describe the clinical presentation of chikungunya virus (CHIKV) infection in patients living with HIV (PLHIV) during the 2014 Martinique outbreak. During the outbreak and the 6 following months, all PLHIV coming in our unit for a medical evaluation answered questions about potential CHIKV related symptoms, and had blood tests to assess the diagnosis. For patients coming in at the acute phase of infection, we are able to provide and analyze CD4+, CD8+ T-cells and HIV viral load evolution before, during and after CHIK infection. Among the 1 003 PLHIV in care in the center at the time of the outbreak, 188 (94 men and 94 women) had confirmed (following the WHO definition) CHIKV infection. Clinical presentation was common in 63% of the cases, severe and atypical forms were scarce. During the acute phase, CD4+ and CD8+ T-cells (evaluated in 30 PLHIV, 15 men and 15 women) absolute numbers dropped significantly, but returned to pre-CHIKV values after the acute phase. Reassuringly, CD4 and CD8 T cells proportions did not decrease during the acute phase. CHIKV infection had no significant impact on this anti-retroviral treated population.


Assuntos
Febre de Chikungunya/complicações , Vírus Chikungunya/fisiologia , Surtos de Doenças , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Adolescente , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Martinica/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem
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