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1.
Mem Inst Oswaldo Cruz ; 115: e200218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696917

RESUMO

BACKGROUND: Southeast Brazil has recently experienced a Yellow Fever virus (YFV) outbreak where the mosquito Haemagogus leucocelaenus was a primary vector. Climatic factors influence the abundance of mosquito vectors and arbovirus transmission. OBJECTIVES: We aimed at describing the population dynamics of Hg. leucocelaenus in a county touched by the recent YFV outbreak. METHODS: Fortnightly egg collections with ovitraps were performed from November 2012 to February 2017 in a forest in Nova Iguaçu, Rio de Janeiro, Brazil. The effects of mean temperature and rainfall on the Hg. leucocelaenus population dynamics were explored. FINDINGS: Hg. leucocelaenus eggs were continuously collected throughout the study, with a peak in the warmer months (December-March). The climatic variables had a time-lagged effect and four weeks before sampling was the best predictor for the positivity of ovitraps and total number of eggs collected. The probability of finding > 50% positive ovitraps increased when the mean temperature was above 24ºC. The number of Hg. leucocelaenus eggs expressively increase when the mean temperature and accumulated precipitation surpassed 27ºC and 100 mm, respectively, although the effect of rainfall was less pronounced. MAIN CONCLUSIONS: Monitoring population dynamics of Hg. leucocelaenus and climatic factors in YFV risk areas, especially mean temperature, may assist in developing climate-based surveillance procedures to timely strengthening prophylaxis and control.


Assuntos
Culicidae/virologia , Florestas , Insetos Vetores/virologia , Dinâmica Populacional , Febre Amarela , Vírus da Febre Amarela/isolamento & purificação , Animais , Brasil , Culicidae/classificação , Insetos Vetores/classificação , Estações do Ano , Temperatura , Vírus da Febre Amarela/genética
2.
PLoS One ; 15(5): e0232585, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374750

RESUMO

Neurotropic flavivirus Japanese encephalitis virus (JEV) and West Nile virus (WNV) are amongst the leading causes of encephalitis. Using label-free quantitative proteomics, we identified proteins differentially expressed upon JEV (gp-3, RP9) or WNV (IS98) infection of human neuroblastoma cells. Data are available via ProteomeXchange with identifier PXD016805. Both viruses were associated with the up-regulation of immune response (IFIT1/3/5, ISG15, OAS, STAT1, IRF9) and the down-regulation of SSBP2 and PAM, involved in gene expression and in neuropeptide amidation respectively. Proteins associated to membranes, involved in extracellular matrix organization and collagen metabolism represented major clusters down-regulated by JEV and WNV. Moreover, transcription regulation and mRNA processing clusters were also heavily regulated by both viruses. The proteome of neuroblastoma cells infected by JEV or WNV was significantly modulated in the presence of mosquito saliva, but distinct patterns were associated to each virus. Mosquito saliva favored modulation of proteins associated with gene regulation in JEV infected neuroblastoma cells while modulation of proteins associated with protein maturation, signal transduction and ion transporters was found in WNV infected neuroblastoma cells.


Assuntos
Culicidae/metabolismo , Encefalite Japonesa/metabolismo , Neurônios/patologia , Proteoma/metabolismo , Febre do Nilo Ocidental/metabolismo , Animais , Linhagem Celular Tumoral , Culicidae/virologia , Vírus da Encefalite Japonesa (Subgrupo)/isolamento & purificação , Encefalite Japonesa/patologia , Encefalite Japonesa/virologia , Feminino , Humanos , Neurônios/metabolismo , Neurônios/virologia , Proteoma/análise , Saliva/metabolismo , Saliva/virologia , Febre do Nilo Ocidental/patologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação
3.
Rev Soc Bras Med Trop ; 53: e20190439, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321091

RESUMO

INTRODUCTION: DENV-2 is the cause of most dengue epidemics worldwide and is associated with severe cases. METHODS: We investigated arboviruses in 164 serum samples collected from patients presenting with clinical symptoms of dengue fever and 152 mosquito pools. RESULTS: We detected the Asian II genotype of DENV-2 in humans and mosquitoes. Our results confirmed the circulation of the Asian II genotype in Brazil, in addition to the prevalent Asian/American genotype. CONCLUSIONS: The detection of Asian II genotype of DENV-2 in mosquito pools collected in a forest park may be related to a spillback event of human dengue virus.


Assuntos
Culicidae/virologia , Vírus da Dengue/genética , Dengue/virologia , Animais , Brasil , Culicidae/classificação , Genótipo , Humanos , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/genética , Estações do Ano
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(4): 571-579, 2020 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-32344484

RESUMO

Objective: To investigate the types and distribution of blood-sucking insects and arboviruses in Inner Mongolia autonomous region, and provide basic data for the prevention of arbovirus transmitted disease. Methods: Blood-sucking insects were collected by lamp trapping method in nature. Mosquito samples were classified according to morphologic characteristics and then stored at liquid nitrogen. Viruses were isolated in cell culture and characterized, using molecular biological methods. Results: A total of 24 240 mosquitoes and 17 110 aphids were collected from 2 sites of 5 counties (Flags) in Inner Mongolia in 2014 and during 2017-2018. Among them, Japanese encephalitis virus gene was detected in Culex pipiens pallens, and 4 virus strains isolates which could be stably passaged. The isolates were identified as Getah virus and densonucleosis virus by molecular biology identification. Phylogenetic analysis on the E2 gene of the Getah virus (NMDK1813-1) showed that it belonged to the same evolutionary branch of the Gansu isolates (GS10-2) and having six common amino acid variation sites. Conclusions: The emergence of Japanese encephalitis virus and Getah virus from specimen of mosquitoes in Inner Mongolia indicated the new challenges on the prevention and control of arbovirus and related diseases. The results pf this study provided basic data for the prevention and control stretagies of arbovirus transmitted diseases in Inner Mongolia.


Assuntos
Alphavirus/isolamento & purificação , Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Encefalite Japonesa , Mosquitos Vetores/virologia , RNA Viral/genética , Animais , China , Filogenia , RNA Viral/isolamento & purificação
5.
Am J Trop Med Hyg ; 102(5): 964-970, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32228777

RESUMO

Two confirmed human cases of Zika virus (ZIKV) were reported in the district of Miri, Sarawak, in 2016. Following that, a mosquito-based ZIKV surveillance study was conducted within 200-m radius from the case houses. Mosquito surveillance was conducted using five different methods, that is, biogents sentinel mosquito (BG) sentinel trap, modified sticky ovitrap, resting catch, larval surveillance, and conventional ovitrap. A total of 527 and 390 mosquito samples were obtained from the case houses in two localities, namely, Kampung Lopeng and Taman Shang Ri La, Miri, Sarawak, respectively. All mosquitoes collected were identified, which consisted of 11 species. Aedes albopictus, both the adult and larval stages, was the dominant species. Resting catch method obtained the highest number of adult mosquitoes (67%), whereas ovitrap showed the highest catch for larval mosquitoes (84%). Zika virus was detected in both adults and larvae of Ae. albopictus together with adults of Culex gelidus, and Culex quinquefasciatus using the real-time reverse transcriptase polymerase chain reaction (PCR) technique. It was noteworthy that Ae. albopictus positive with ZIKV were caught and obtained from four types of collection method. By contrast, Cx. gelidus and Culex quinquefasciatus adults collected from sticky ovitraps were also found positive with ZIKV. This study reveals vital information regarding the potential vectors of ZIKV and the possibility of transovarian transmission of the virus in Malaysia. These findings will be essentials for vector control program managers to devise preparedness and contingency plans of prevention and control of the arboviral disease.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/epidemiologia , Aedes/virologia , Animais , Culex/virologia , Feminino , Humanos , Malásia/epidemiologia , Masculino , Vigilância da População , Reação em Cadeia da Polimerase em Tempo Real , Infecção por Zika virus/etiologia , Infecção por Zika virus/transmissão
6.
Epidemiol Infect ; 148: e72, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32234110

RESUMO

From 1971 to 2012, in New York State, years with human Eastern equine encephalitis (EEE) were more strongly associated with the presence of Aedes canadensis, Coquillettidia perturbans and Culiseta melanura mosquitoes infected with the EEE virus (Fisher's exact test, one-sided P = 0.005, 0.03, 0.03) than with Culiseta morsitans, Aedes vexans, Culex pipiens-restuans, Anopheles quadrimaculatus or Anopheles punctipennis (P = 0.05, 0.40, 0.33, 1.00, 1.00). The estimated relative risk of a case in a year in which the virus was detected vs. not detected was 14.67 for Ae. canadensis, 6.38 for Cq. perturbans and 5.50 for Cs. morsitans. In all 5 years with a case, Cs. melanura with the virus was detected. In no year was there a case in the absence of Cs. melanura with the virus. There were 18 years with no case in the presence of Cs. melanura with the virus. Such observations may identify the time of increased risk, and when the methods may be used to prevent or reduce exposure to vector mosquito species in this geographic region.


Assuntos
Culicidae/virologia , Vírus da Encefalite Equina do Leste , Encefalomielite Equina do Leste , Mosquitos Vetores/virologia , Aedes/virologia , Animais , Encefalomielite Equina do Leste/epidemiologia , Encefalomielite Equina do Leste/transmissão , Encefalomielite Equina do Leste/virologia , Humanos , New York , Análise Espaço-Temporal
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(2): 236-243, 2020 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-32164136

RESUMO

Objective: To understand the types and distribution of Arboviruses in Hainan province. Methods: Blood-sucking insects were collected in Hainan province from 2017 to 2018. After laboratory treatment, BHK-21 cells and C6/36 cells were inoculated with grinding supernatant of all blood-sucking insects to isolate all of involving virus. Arbovirus genes in blood-sucking insects were detected in parallel by RT-PCR method. Results: A total of 15 062 mosquitoes were classified into four genera (Culex, Armigeres, Aedes, Anopheles) and 11 360 midges were collected. Culex tritaeniorhynchus was in the majority and accounted for 92.88% (13 990/15 062) of all the mosquitoes collected. Four strains of virus isolates were notified by tissue culture method. Three strains of viruses belonged to Japanese encephalitis virus (JEV), with the other one as Getah virus (GETV). Five pools of JEV gene amplification were positive, from Culex tritaeniorhynchus. Results from the phylogenetic analysis showed that they belonged to genotype JEV-Ⅰ. The minimum infection rate of JEV was 0.57‰ (8/13 990). A total of 5 pools of Akabane virus (AKV) gene amplification were positive. The minimum infection rate of AKV was 0.44‰ (5/11 360). Based on the S gene and M gene sequences of the virus, data from the phylogenetic analysis showed that the five AKV strains carried by midges in Hainan province were in a separate evolutionary branch and with formed unique geographical distribution. Conclusions: JEV and GETV had been isolated again from the mosquito specimens in this survey, since the 1980s. AKV was detected from the midge specimens in Hainan province. These results showed the needs of strengthening the programs on detection and monitor of JEV, GETV and AKV that were related to animal and human diseases in order to reduce the risks of related diseases in this area.


Assuntos
Arbovirus/genética , Arbovirus/isolamento & purificação , Culicidae/virologia , Alphavirus/genética , Alphavirus/isolamento & purificação , Animais , China , Culex/virologia , Vírus da Encefalite Japonesa (Espécie)/genética , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Humanos , Filogenia
8.
PLoS Negl Trop Dis ; 14(3): e0008166, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32203536

RESUMO

Flaviviruses such as yellow fever, dengue or Zika viruses are responsible for significant human and veterinary diseases worldwide. These viruses contain an RNA genome, prone to mutations, which enhances their potential to emerge as pathogens. Bamaga virus (BgV) is a mosquito-borne flavivirus in the yellow fever virus group that we have previously shown to be host-restricted in vertebrates and horizontally transmissible by Culex mosquitoes. Here, we aimed to characterise BgV host-restriction and to investigate the mechanisms involved. We showed that BgV could not replicate in a wide range of vertebrate cell lines and animal species. We determined that the mechanisms involved in BgV host-restriction were independent of the type-1 interferon response and RNAse L activity. Using a BgV infectious clone and two chimeric viruses generated as hybrids between BgV and West Nile virus, we demonstrated that BgV host-restriction occurred post-cell entry. Notably, BgV host-restriction was shown to be temperature-dependent, as BgV replicated in all vertebrate cell lines at 34°C but only in a subset at 37°C. Serial passaging of BgV in Vero cells resulted in adaptive mutants capable of efficient replication at 37°C. The identified mutations resulted in amino acid substitutions in NS4A-S124F, NS4B-N244K and NS5-G2C, all occurring close to a viral protease cleavage site (NS4A/2K and NS4B/NS5). These mutations were reverse engineered into infectious clones of BgV, which revealed that NS4B-N244K and NS5-G2C were sufficient to restore BgV replication in vertebrate cells at 37°C, while NS4A-S124F further increased replication efficiency. When these mutant viruses were injected into immunocompetent mice, alongside BgV and West Nile virus chimeras, infection and neurovirulence were enhanced as determined by clinical scores, seroconversion, micro-neutralisation, viremia, histopathology and immunohistochemistry, confirming the involvement of these residues in the attenuation of BgV. Our studies identify a new mechanism of host-restriction and attenuation of a mosquito-borne flavivirus.


Assuntos
Infecções por Flavivirus/virologia , Flavivirus/genética , Flavivirus/patogenicidade , Mutação , Proteínas não Estruturais Virais/genética , Animais , Encéfalo/patologia , Encéfalo/virologia , Linhagem Celular , Chlorocebus aethiops , Culicidae/virologia , Modelos Animais de Doenças , Endorribonucleases/metabolismo , Feminino , Flavivirus/fisiologia , Infecções por Flavivirus/metabolismo , Infecções por Flavivirus/patologia , Células HEK293 , Humanos , Masculino , Camundongos , Mosquitos Vetores/virologia , Células Vero , Virulência/genética , Replicação Viral , Vírus do Nilo Ocidental/genética
9.
Cell Host Microbe ; 27(3): 329-344, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32164844

RESUMO

The intestine is an essential physical and immunological barrier comprised of a monolayer of diverse and specialized epithelial cells that perform functions ranging from nutrient absorption to pathogen sensing and intestinal homeostasis. The intestinal barrier prevents translocation of intestinal microbes into internal compartments. The microbiota is comprised of a complex community largely populated by diverse bacterial species that provide metabolites, nutrients, and immune stimuli that promote intestinal and organismal health. Although commensal organisms promote health, enteric pathogens, including a diverse plethora of enteric viruses, cause acute and chronic diseases. The barrier epithelium plays fundamental roles in immune defenses against enteric viral infections by integrating diverse signals, including those from the microbiota, to prevent disease. Importantly, many model systems have contributed to our understanding of this complex interface. This review will focus on the antiviral mechanisms at play within the intestinal epithelium and how these responses are shaped by the microbiota.


Assuntos
Microbioma Gastrointestinal , Enteropatias/virologia , Mucosa Intestinal/microbiologia , Viroses/patologia , Animais , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/virologia , Culicidae/imunologia , Culicidae/virologia , Drosophila melanogaster/imunologia , Drosophila melanogaster/virologia , Humanos , Imunidade Inata , Camundongos , Viroses/microbiologia
10.
PLoS Negl Trop Dis ; 14(2): e0008066, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32092063

RESUMO

BACKGROUND: In the northeast United States (U.S.), mosquitoes transmit a number of arboviruses, including eastern equine encephalitis, Jamestown Canyon, and West Nile that pose an annual threat to human and animal health. Local transmission of each arbovirus may be driven by the involvement of multiple mosquito species; however, the specificity of these vector-virus associations has not been fully quantified. METHODOLOGY: We used long-term surveillance data consistently collected over 18 years to evaluate mosquito and arbovirus community composition in the State of Connecticut (CT) based on land cover classifications and mosquito species-specific natural histories using community ecology approaches available in the R package VEGAN. We then used binomial-error generalized linear mixed effects models to quantify species-specific trends in arbovirus detections. PRIMARY RESULTS: The composition of mosquito communities throughout CT varied more among sites than among years, with variation in mosquito community composition among sites explained mostly by a forested-to-developed-land-cover gradient. Arboviral communities varied equally among sites and years, and only developed and forested wetland land cover classifications were associated with the composition of arbovirus detections among sites. Overall, the avian host arboviruses, mainly West Nile and eastern equine encephalitis, displayed the most specific associations among mosquito species and sites, while in contrast, the mammalian host arboviruses (including Cache Valley, Jamestown Canyon, and Potosi) associated with a more diverse mix of mosquito species and were widely distributed throughout CT. CONCLUSIONS: We find that avian arboviruses act as vector specialists infecting a few key mosquito species that associate with discrete habitats, while mammalian arboviruses are largely vector generalists infecting a wide diversity of mosquito species and habitats in the region. These distinctions have important implications for the design and implementation of mosquito and arbovirus surveillance programs as well as mosquito control efforts.


Assuntos
Arbovirus/fisiologia , Culicidae/virologia , Animais , Arbovirus/classificação , Connecticut , Feminino , Interações Hospedeiro-Patógeno , Humanos , Mosquitos Vetores/virologia , Estudos Retrospectivos
11.
Yi Chuan ; 42(2): 153-160, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32102772

RESUMO

Mosquito-borne diseases have become an important public health issue of global concern because of their high incidence and transmission rate. As a vector for mosquito-borne diseases, studying the interaction mechanism between mosquitoes and mosquito-borne viruses will help control mosquito-borne diseases. The impaired innate immunity and immune barriers evasion caused by mosquito-borne viruses in mosquitoes pose a potential risk for the persistent infection of the virus in mosquitoes and the outbreak of mosquito-borne diseases. The RNA interference (RNAi) pathway, as a powerful antiviral defense barrier in mosquitoes, can inhibit viral replication and transmission by producing a variety of small RNAs to degrade viral RNA. In this review, we summarize the related studies on the innate immune mechanism against mosquito- borne virus infection in mosquitoes about small interfering RNA (siRNA), microRNA (miRNA), and Piwi-interacting RNA (piRNA), aiming to provide a theoretical reference for the prevention and control of mosquito-borne diseases.


Assuntos
Culicidae/virologia , Interferência de RNA , Viroses , Animais , Culicidae/imunologia , Imunidade Inata , Mosquitos Vetores/imunologia , Mosquitos Vetores/virologia , RNA Interferente Pequeno , Viroses/prevenção & controle , Viroses/transmissão
12.
Cell Host Microbe ; 27(1): 14-24, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31917957

RESUMO

Humoral immunity is an essential component of the protective immune response to flavivirus infection. Typically, primary infection generates a robust neutralizing antibody response that mediates viral control and protection. It is becoming increasingly apparent that secondary infection with a closely related flavivirus strain can result in immunological cross-reactivity; however, the consequences to infection outcome remain controversial. Since its introduction to Brazil in 2015, Zika virus (ZIKV) has caused an epidemic of fetal congenital malformations within the Americas. Because ZIKV is a mosquito-borne flavivirus with a high degree of sequence and structural homology to Dengue virus (DENV), the role of immunological cross-reactivity in ZIKV and DENV infections has become a great concern. In this review, we highlight contemporary findings that implicate a role for flavivirus antibodies in mediating protection, contributing to pathogenesis, and seeding the human placenta.


Assuntos
Vírus da Dengue/imunologia , Flavivirus/imunologia , Placenta/virologia , Infecção por Zika virus , Zika virus/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais , Reações Cruzadas/imunologia , Culicidae/virologia , Dengue/imunologia , Feminino , Humanos , Imunidade Humoral , Transmissão Vertical de Doença Infecciosa , Placenta/imunologia , Gravidez , Vacinas Virais , Infecção por Zika virus/imunologia , Infecção por Zika virus/patologia , Infecção por Zika virus/terapia
13.
Virol J ; 17(1): 9, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31973727

RESUMO

Yellow fever (YF) is an acute viral disease, affecting humans and non-human primates (NHP), caused by the yellow fever virus (YFV). Despite the existence of a safe vaccine, YF continues to cause morbidity and mortality in thousands of people in Africa and South America. Since 2016, massive YF outbreaks have taken place in Brazil, reaching YF-free zones, causing thousands of deaths of humans and NHP. Here we reviewed the main epidemiological aspects, new clinical findings in humans, and issues regarding YFV infection in vectors and NHP in Brazil. The 2016-2019 YF epidemics have been considered the most significant outbreaks of the last 70 years in the country, and the number of human cases was 2.8 times higher than total cases in the previous 36 years. A new YFV lineage was associated with the recent outbreaks, with persistent circulation in Southeast Brazil until 2019. Due to the high number of infected patients, it was possible to evaluate severity and death predictors and new clinical features of YF. Haemagogus janthinomys and Haemagogus leucocelaenus were considered the primary vectors during the outbreaks, and no human case suggested the occurrence of the urban transmission cycle. YFV was detected in a variety of NHP specimens presenting viscerotropic disease, similar to that described experimentally. Further studies regarding NHP sensitivity to YFV, YF pathogenesis, and the duration of the immune response in NHP could contribute to YF surveillance, control, and future strategies for NHP conservation.


Assuntos
Febre Amarela , Vírus da Febre Amarela , Aedes/virologia , Animais , Brasil/epidemiologia , Culicidae/virologia , Surtos de Doenças , Reservatórios de Doenças/virologia , Epidemias , Humanos , Mosquitos Vetores/virologia , Primatas/virologia , Viroses/epidemiologia , Febre Amarela/epidemiologia , Febre Amarela/prevenção & controle , Febre Amarela/transmissão , Vírus da Febre Amarela/imunologia , Vírus da Febre Amarela/isolamento & purificação , Vírus da Febre Amarela/patogenicidade , Zoonoses/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
15.
Acta Microbiol Immunol Hung ; 66(4): 423-442, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31658836

RESUMO

Zika virus is a mosquito-borne flavivirus with significant public health concern due to its association with neurological symptoms and intrauterine malformations. Although it is endemic in tropical and subtropical areas, sexual transmission raises the possibility of autochthonous spreading elsewhere. We describe the first laboratory diagnosed imported Zika-infections of Hungary, to highlight the challenges of microbiological identification of the pathogen, caused by serological cross-reactivity and short viremia. Serological examination was carried out using indirect immunofluorescent assay and enzyme-linked immunosorbent assay. Plaque-reduction neutralization test was used for verification purposes. A wide range of clinical specimens: serum, whole-blood, urine, saliva, and semen were analyzed by molecular methods, and sequencing was applied in case of PCR positive results to identify the virus strain. Zika-infected patients with previous vaccination against flaviviruses or possible flavivirus infection in the past showed high serological cross-reactivity, and even cross-neutralizing antibodies were observed. Zika virus RNA could be detected in urine specimen in case of two patients, and in EDTA-anticoagulated whole-blood sample of one patient. The detected strains belong to the Asian lineage of the virus. We presume that serological investigation of imported Zika virus could be altered by infections, vaccination of endemic flaviviruses in Hungary and vice versa.


Assuntos
Anticorpos Antivirais/sangue , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia , Adulto , Idoso , Animais , Técnicas de Laboratório Clínico , Reações Cruzadas , Culicidae/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hungria/epidemiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Testes de Neutralização , Infecção por Zika virus/imunologia
16.
J Am Mosq Control Assoc ; 35(3): 220-223, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31647704

RESUMO

An arbovirus surveillance military exercise was conducted to assess the risk of Ross River virus (RRV) and Barmah Forest virus (BFV) in the Australian Defence Force (ADF) Wide Bay training area (WBTA), northeastern Australia, in April 2018. Of the 5,540 female mosquitoes collected, 3,702 were screened for RRV and BFV by quantitative reverse transcription-polymerase chain reaction in a field laboratory. One pool of Verrallina funerea was positive for RRV and 8 pools (7 pools of Aedes vigilax and 1 pool of Culex annulirostris) were positive for BFV. Phylogenetic analysis of the complete nucleotide sequence of the E2 protein subgrouped both RRV and BFV with viruses previously isolated from human infections, indicating the potential risk of RRV and BFV infection to ADF personnel while training in WBTA. This is the 1st time that both RRV and BFV have been detected in a military training area.


Assuntos
Alphavirus/isolamento & purificação , Culicidae/virologia , Vírus do Rio Ross/isolamento & purificação , Alphavirus/genética , Animais , Feminino , Militares , Vigilância da População , Queensland , Vírus do Rio Ross/genética
17.
Int J Infect Dis ; 89: 169-174, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606414

RESUMO

BACKGROUND: Arboviral diseases are a global growing problem due to climate change, urbanization, population density, and global transportation. However, new technologies currently being developed in research labs are expected to play a relevant role in combatting arboviral diseases in the future, reducing the health and economic burden imposed by these diseases. OBJECTIVES: This paper aims to anticipate the technologies that might be relevant for prevention and vector control of arboviral diseases in the future. METHODS: A web-based survey was conducted of over 2,000 experts from all over the world. Both the technologies and the respondents were identified from recent scientific publications on arboviral diseases indexed in the Web of Science Core Collection. RESULTS: Our results show that within 20 years the enveloped virus-like particles-based vaccine and the gene-edited mosquitoes through CRISPR/Cas9 will likely be the most promising technologies for, respectively, prevention and vector control of arboviral diseases. CONCLUSIONS: If these expectations are confirmed, these new technologies, when fully developed, may support global public health efforts aimed at reducing transmission, mortality and morbidity of arboviral diseases.


Assuntos
Infecções por Arbovirus/prevenção & controle , Arbovirus/fisiologia , Culicidae/virologia , Mosquitos Vetores/fisiologia , Animais , Infecções por Arbovirus/epidemiologia , Infecções por Arbovirus/transmissão , Infecções por Arbovirus/virologia , Culicidae/genética , Culicidae/fisiologia , Humanos , Controle de Mosquitos , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , Saúde Pública , Vacinas Virais/administração & dosagem
18.
J Med Entomol ; 56(6): 1467-1474, 2019 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-31549720

RESUMO

West Nile virus (WNV) was first identified in North America almost 20 yr ago. In that time, WNV has crossed the continent and established enzootic transmission cycles, resulting in intermittent outbreaks of human disease that have largely been linked with climatic variables and waning avian seroprevalence. During the transcontinental dissemination of WNV, the original genotype has been displaced by two principal extant genotypes which contain an envelope mutation that has been associated with enhanced vector competence by Culex pipiens L. (Diptera: Culicidae) and Culex tarsalis Coquillett vectors. Analyses of retrospective avian host competence data generated using the founding NY99 genotype strain have demonstrated a steady reduction in viremias of house sparrows over time. Reciprocally, the current genotype strains WN02 and SW03 have demonstrated an inverse correlation between house sparrow viremia magnitude and the time since isolation. These data collectively indicate that WNV has evolved for increased avian viremia while house sparrows have evolved resistance to the virus such that the relative host competence has remained constant. Intrahost analyses of WNV evolution demonstrate that selection pressures are avian species-specific and purifying selection is greater in individual birds compared with individual mosquitoes, suggesting that the avian adaptive and/or innate immune response may impose a selection pressure on WNV. Phylogenomic, experimental evolutionary systems, and models that link viral evolution with climate, host, and vector competence studies will be needed to identify the relative effect of different selective and stochastic mechanisms on viral phenotypes and the capacity of newly evolved WNV genotypes for transmission in continuously changing landscapes.


Assuntos
Doenças das Aves/epidemiologia , Aves , Culicidae/virologia , Genoma Viral , Interações Hospedeiro-Patógeno , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/fisiologia , Animais , Doenças das Aves/virologia , Meio Ambiente , América do Norte , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/crescimento & desenvolvimento
19.
Indian J Med Res ; 149(6): 771-777, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31496530

RESUMO

Background & objectives: Chikungunya virus (CHIKV), a mosquito-borne arthritogenic virus causes infections ranging from febrile illness to debilitating polyarthralgia in humans. Re-emergence of the virus has affected millions of people in Africa and Asia since 2004. During the outbreak, a new lineage of the virus has evolved as an adaptation for enhanced replication and transmission by Aedes albopictus mosquito. A study was designed to compare the susceptibility of four vertebrate cell lines, namely Vero E6 (African green monkey kidney), BHK-21 (Baby hamster kidney), RD (human rhabdomyosarcoma), A-549 (human alveolar basal epithelial cell) and C6/36 (Ae. albopictus) to Asian genotype and two lineages of East, Central and South African (E1:A226 and E1:A226V) of CHIKV. Methods: One-step growth kinetics of different CHIKV strains was carried out in the above five cell lines to determine the growth kinetics and virus yield. Virus titre was determined by 50 per cent tissue culture infectious dose assay and titres were calculated by the Reed and Muench formula. Growth and virus yield of the three strains in Ae. aegypti mosquitoes was studied by intrathoracic inoculation and virus titration in Vero E6 cell line. Results: Virus titration showed Vero E6, C6/36 and BHK-21 cell lines are high virus yielding with all the three lineages while RD and A-549 yielded low virus titres. C6/36 cell line was the most sensitive and yielded the maximum titre. Ae. aegypti mosquitoes, when inoculated with high titre virus, yielded an almost equal growth with the three strains while rapid growth of E1:A226V and Asian strain was observed with 1 log virus. Interpretation & conclusions: C6/36 cell line was found to be the most sensitive and high yielding for CHIKV irrespective of lineages while Vero E6 and BHK-21 cell lines yielded high titres and may find application for vaccine/diagnostic development. Infection of Ae. aegypti mosquitoes with the three CHIKV strains gave almost identical pattern of growth.


Assuntos
Aedes/virologia , Febre de Chikungunya/virologia , Vírus Chikungunya/crescimento & desenvolvimento , Culicidae/virologia , Células A549/virologia , África/epidemiologia , Animais , Ásia/epidemiologia , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/genética , Vírus Chikungunya/genética , Vírus Chikungunya/patogenicidade , Chlorocebus aethiops , Surtos de Doenças , Genótipo , Humanos , Mosquitos Vetores/genética , Mosquitos Vetores/crescimento & desenvolvimento , Saliva/virologia , Células Vero/virologia
20.
BMC Vet Res ; 15(1): 320, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488162

RESUMO

BACKGROUND: Getah virus (GETV) is a neglected mosquito-borne Alphavirus that causes pyrexia, body rash, and leg oedema in horses and foetal death and reproductive disorders in pigs. Infected animals may play a critical role in the amplification and circulation of the virus. The present study aimed to investigate GETV infection in clinically infected cattle and vector mosquito species in northeastern China. RESULTS: Serum samples were collected from beef cattle that presented sudden onset of fever in forest grazing areas, and metagenomic sequencing was conducted, revealing 29 contigs from ten serum samples matching the GETV genome. Quantitative RT-PCR (RT-qPCR) was performed with GETV RNA from 48 beef cattle serum samples, showing that the overall prevalence of GETV in the beef cattle samples was 6.25% (3/48). Serological investigation indicated that GETV neutralizing antibodies were detected in 83.3% (40/48, 95% CI 67-100) of samples from the study region. The GETV JL1808 strain was isolated from clinically infected cattle showing fever. Sequence comparisons showed high identity with the HuN1 strain, a highly pathogenic swine epidemic isolate obtained in Hunan province in 2017, at the nucleotide level (99.5%) and at the deduced amino acid level (99.7-99.9%). The phylogenetic analysis of JL1808 clustered in Group III, and also revealed a close genetic relationship with the HuN1 strain. Additionally, about 12,000 mosquitoes were trapped in this region. The presence of GETV infection was detected in mosquitoes, suggesting that the minimum infection rate (MIR) was 1.50‰, with MIRs of 1.67‰ in Culex pseudovishnui, 1.60‰ in Culex tritaeniorhynchus, and 1.21‰ in Anopheles sinensis. CONCLUSIONS: To the best of our knowledge, this is the first report of GETV infection in cattle. These results demonstrated that a highly pathogenic, mosquito-borne swine GETV can infect and circulate in cattle, implying that it is necessary to conduct surveillance of GETV infection in animals in northeastern China.


Assuntos
Infecções por Alphavirus/veterinária , Alphavirus/isolamento & purificação , Doenças dos Bovinos/virologia , Alphavirus/classificação , Infecções por Alphavirus/virologia , Animais , Bovinos , China , Culicidae/virologia , Vetores de Doenças , Filogenia , RNA Viral/isolamento & purificação
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