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1.
Nat Commun ; 12(1): 3431, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103499

RESUMO

The current COVID-19 pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We demonstrate that despite the large size of the viral RNA genome (~30 kb), infectious full-length cDNA is readily assembled in vitro by a circular polymerase extension reaction (CPER) methodology without the need for technically demanding intermediate steps. Overlapping cDNA fragments are generated from viral RNA and assembled together with a linker fragment containing CMV promoter into a circular full-length viral cDNA in a single reaction. Transfection of the circular cDNA into mammalian cells results in the recovery of infectious SARS-CoV-2 virus that exhibits properties comparable to the parental virus in vitro and in vivo. CPER is also used to generate insect-specific Casuarina virus with ~20 kb genome and the human pathogens Ross River virus (Alphavirus) and Norovirus (Calicivirus), with the latter from a clinical sample. Additionally, reporter and mutant viruses are generated and employed to study virus replication and virus-receptor interactions.


Assuntos
Genética Reversa , SARS-CoV-2/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Chlorocebus aethiops , Culicidae/virologia , Furina/metabolismo , Genoma Viral , Células HEK293 , Humanos , Camundongos , Mutação/genética , Células NIH 3T3 , Reação em Cadeia da Polimerase , Células RAW 264.7 , Receptores Virais/metabolismo , Células Vero , Proteínas Virais/química , Replicação Viral
2.
Public Health ; 192: 21-29, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33607517

RESUMO

OBJECTIVES: The primary aim of this study was to evaluate the temporal correlation between Wikitrends and conventional surveillance data generated for Chikungunya, Dengue, Zika, and West Nile Virus infection reported by bulletin of Italian National Institute of Health (Istituto Superiore di Sanità in italian, ISS). STUDY DESIGN: A cross-sectional study design was used. METHODS: The reported cases of Dengue and Chikungunya were selected from July 2015 to December 2019. For West Nile Virus, the bulletins are issued in the period June-November (6 months) of the years 2015-2019, and for Zika virus, the data reported in the ISS bulletin start from January 2016. From Wikipedia Trends, we extracted the number of monthly views by users from the July 2015 to December 2019 of the pages Chikungunya, Dengue, Zika virus, and West Nile Virus. RESULTS: A correlation was observed between the bulletin of ISS and Wikipedia Wikitrends, the correlation was strong for Chikungunya and West Nile Virus (r = 0.9605; r = 0.9556, respectively), and highly statistically significant with P-values <0.001. The correlation was moderate for Dengue and Zika virus (r = 0.6053; r = 0.5888, respectively), but highly statistically significant with P-values <0.001. CONCLUSIONS: Classical surveillance system should be integrated with the tools of digital epidemiology that have potential role in public health for the dynamic information and provide near real-time indicators of the spread of infectious disease.


Assuntos
Arbovírus , Febre de Chikungunya/epidemiologia , Culicidae/virologia , Dengue/epidemiologia , Internet , Febre do Nilo Ocidental/epidemiologia , Infecção por Zika virus/epidemiologia , Animais , Arbovírus/classificação , Arbovírus/isolamento & purificação , Vírus Chikungunya , Estudos Transversais , Dengue/virologia , Vírus da Dengue , Monitoramento Epidemiológico , Humanos , Itália/epidemiologia , Masculino , Saúde Pública , Vírus do Nilo Ocidental , Zika virus
3.
Nat Rev Microbiol ; 19(3): 184-195, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33432235

RESUMO

Transmission of arthropod-borne viruses (arboviruses) involves infection and replication in both arthropod vectors and vertebrate hosts. Nearly all arboviruses are RNA viruses with high mutation frequencies, which leaves them vulnerable to genetic drift and fitness losses owing to population bottlenecks during vector infection, dissemination from the midgut to the salivary glands and transmission to the vertebrate host. However, despite these bottlenecks, they seem to avoid fitness declines that can result from Muller's ratchet. In addition, founder effects that occur during the geographic introductions of human-amplified arboviruses, including chikungunya virus and Zika virus, can affect epidemic and endemic circulation, as well as virulence. In this Review, we discuss the role of genetic drift following population bottlenecks and founder effects in arboviral evolution and spread, and the emergence of human disease.


Assuntos
Infecções por Arbovirus/transmissão , Infecções por Arbovirus/virologia , Arbovírus/genética , Culicidae/virologia , Doenças Transmitidas por Vetores/virologia , Animais , Deriva Genética , Genômica , Humanos
4.
Viruses ; 12(12)2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339099

RESUMO

RNA of Kyzylagach virus (KYZV), a Sindbis-like mosquito-borne alphavirus from Western equine encephalitis virus complex, was detected in four pools (out of 221 pools examined), encompassing 10,784 female Culex modestus mosquitoes collected at a fishpond in south Moravia, Czech Republic, with a minimum infection rate of 0.04%. This alphavirus was never detected in Central Europe before.


Assuntos
Infecções por Alphavirus/transmissão , Infecções por Alphavirus/virologia , Culicidae/virologia , Mosquitos Vetores/virologia , Vírus Sindbis , Animais , Europa (Continente)/epidemiologia , Feminino
5.
PLoS One ; 15(12): e0244587, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33378361

RESUMO

Our previous studies have shown that Zika virus (ZIKV) replicates in human prostate cells, suggesting that the prostate may serve as a long-term reservoir for virus transmission. Here, we demonstrated that the innate immune responses generated to three distinct ZIKV strains (all isolated from human serum) were significantly different and dependent on their passage history (in mosquito, monkey, or human cells). In addition, some of these phenotypic differences were reduced by a single additional cell culture passage, suggesting that viruses that have been passaged more than 3 times from the patient sample will no longer reflect natural phenotypes. Two of the ZIKV strains analyzed induced high levels of the IP-10 chemokine and IFNγ in human prostate epithelial and stromal mesenchymal stem cells. To further understand the importance of these innate responses on ZIKV replication, we measured the effects of IP-10 and its downstream receptor, CXCR3, on RNA and virus production in prostate cells. Treatment with IP-10, CXCR3 agonist, or CXCR3 antagonist significantly altered ZIKV viral gene expression, depending on their passage in cells of relevant hosts (mosquito or human). We detected differences in gene expression of two primary CXCR3 isoforms (CXCR3-A and CXCR3-B) on the two cell types, possibly explaining differences in viral output. Lastly, we examined the effects of IP-10, agonist, or antagonist on cell death and proliferation under physiologically relevant infection rates, and detected no significant differences. Although we did not measure protein expression directly, our results indicate that CXCR3 signaling may be a target for therapeutics, to ultimately stop sexual transmission of this virus.


Assuntos
Quimiocina CXCL10/metabolismo , Próstata/virologia , Receptores CXCR3/metabolismo , Infecção por Zika virus/imunologia , Zika virus/fisiologia , Animais , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Quimiocina CXCL10/genética , Culicidae/virologia , Regulação da Expressão Gênica , Haplorrinos/virologia , Humanos , Imunidade Inata , Masculino , Próstata/citologia , Próstata/imunologia , Receptores CXCR3/genética , Inoculações Seriadas , Transdução de Sinais , Replicação Viral , Zika virus/imunologia , Infecção por Zika virus/genética , Infecção por Zika virus/virologia
6.
Viruses ; 13(1)2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374822

RESUMO

Flaviviruses are a group of positive-sense RNA viruses that are primarily transmitted through arthropod vectors and are capable of causing a broad spectrum of diseases. Many of the flaviviruses that are pathogenic in humans are transmitted specifically through mosquito vectors. Over the past century, many mosquito-borne flavivirus infections have emerged and re-emerged, and are of global importance with hundreds of millions of infections occurring yearly. There is a need for novel, effective, and accessible vaccines and antivirals capable of inhibiting flavivirus infection and ameliorating disease. The development of therapeutics targeting viral entry has long been a goal of antiviral research, but most efforts are hindered by the lack of broad-spectrum potency or toxicities associated with on-target effects, since many host proteins necessary for viral entry are also essential for host cell biology. Mosquito-borne flaviviruses generally enter cells by clathrin-mediated endocytosis (CME), and recent studies suggest that a subset of these viruses can be internalized through a specialized form of CME that has additional dependencies distinct from canonical CME pathways, and antivirals targeting this pathway have been discovered. In this review, we discuss the role and contribution of endocytosis to mosquito-borne flavivirus entry as well as consider past and future efforts to target endocytosis for therapeutic interventions.


Assuntos
Culicidae/virologia , Endocitose , Infecções por Flavivirus/transmissão , Infecções por Flavivirus/virologia , Flavivirus/fisiologia , Interações Hospedeiro-Patógeno , Animais , Antivirais/farmacologia , Clatrina/metabolismo , Endocitose/imunologia , Flavivirus/efeitos dos fármacos , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/imunologia , Interações Hospedeiro-Patógeno/imunologia , Receptores Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
7.
Viruses ; 13(1)2020 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-33375455

RESUMO

The emergence of arthropod-borne viruses (arboviruses) as linked to land-use changes, especially the growing agricultural intensification and expansion efforts in rural parts of Africa, is of growing health concern. This places an additional burden on health systems as drugs, vaccines, and effective vector-control measures against arboviruses and their vectors remain lacking. An integrated One Health approach holds potential in the control and prevention of arboviruses. Land-use changes favour invasion by invasive alien plants (IAPs) and investigating their impact on mosquito populations may offer a new dimension to our understanding of arbovirus emergence. Of prime importance to understand is how IAPs influence mosquito life-history traits and how this may affect transmission of arboviruses to mammalian hosts, questions that we are exploring in this review. Potential effects of IAPs may be significant, including supporting the proliferation of immature and adult stages of mosquito vectors, providing additional nutrition and suitable microhabitats, and a possible interaction between ingested secondary plant metabolites and arboviruses. We conclude that aspects of vector biology are differentially affected by individual IAPs and that while some plants may have the potential to indirectly increase the risk of transmission of certain arboviruses by their direct interaction with the vectors, the reverse holds for other IAPs. In addition, we highlight priority research areas to improve our understanding of the potential health impacts of IAPs.


Assuntos
Infecções por Arbovirus/epidemiologia , Infecções por Arbovirus/transmissão , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/transmissão , Culicidae/virologia , Espécies Introduzidas , Mosquitos Vetores/virologia , Plantas , Animais , Infecções por Arbovirus/virologia , Doenças Transmissíveis Emergentes/virologia , Ecossistema , Humanos
9.
Korean J Parasitol ; 58(5): 551-558, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33202507

RESUMO

The flaviviruses are small single-stranded RNA viruses that are typically transmitted by mosquitoes or tick vectors and are etiological agents of acute zoonotic infections. The viruses are found around the world and account for significant cases of human diseases. We investigated population of culicine mosquitoes in central region of Korean Peninsula, Incheon Metropolitan City and Hwaseong-si. Aedes vexans nipponii was the most frequently collected mosquitoes (56.5%), followed by Ochlerotatus dorsalis (23.6%), Anopheles spp. (10.9%), and Culex pipiens complex (5.9%). In rural regions of Hwaseong, Aedes vexans nipponii was the highest population (62.9%), followed by Ochlerotatus dorsalis (23.9%) and Anopheles spp. (12.0%). In another rural region of Incheon (habitat of migratory birds), Culex pipiens complex was the highest population (31.4%), followed by Ochlerotatus dorsalis (30.5%), and Aedes vexans vexans (27.5%). Culex pipiens complex was the predominant species in the urban region (84.7%). Culicine mosquitoes were identified at the species level, pooled up to 30 mosquitoes each, and tested for flaviviral RNA using the SYBR Green-based RT-PCR and confirmed by cDNA sequencing. Three of the assayed 2,683 pools (989 pools without Anopheles spp.) were positive for Culex flaviviruses, an insect-specific virus, from Culex pipiens pallens collected at the habitats for migratory birds in Incheon. The maximum likelihood estimation (the estimated number) for Culex pipiens pallens positive for Culex flavivirus was 25. Although viruses responsible for mosquito-borne diseases were not identified, we encourage intensified monitoring and long-term surveillance of both vector and viruses in the interest of global public health.


Assuntos
Culicidae/virologia , Flavivirus , Insetos Vetores/virologia , Animais , Monitoramento Ambiental , Flavivirus/genética , Flavivirus/isolamento & purificação , Humanos , RNA Viral/análise , República da Coreia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
10.
BMC Infect Dis ; 20(1): 790, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33096994

RESUMO

BACKGROUND: Jamestown Canyon virus (JCV) is a mosquito-borne orthobunyavirus that causes acute febrile illness, meningitis, and meningoencephalitis, mainly among adults. JCV is widely distributed in North America and the number of JCV cases in the U.S. has increased in recent years. Therefore, the central nervous system disease caused by JCV can be considered a potentially re-emerging viral disease. However, the seroprevalence of JCV is unknown in Japan. The purpose of this study is to evaluate the seroprevalence of JCV in the Japanese population. METHODS: We used an IgG enzyme-linked immunosorbent assay (IgG-ELISA) with JCV-infected cell-lysates and/or a neutralizing (NT) antibody assay. The cut-off value of IgG-ELISA was determined using IgG-ELISA to analyze serum specimens from 37 healthy Japanese donors. IgG-ELISA was validated by assessing its sensitivity and specificity, using 38 human serum samples previously tested for the presence or absence of antibodies against JCV and snowshoe hare virus (SSHV), in an in-house NT antibody assay conducted by the Public Health Agency of Canada. The seroepidemiological study was performed using IgG-ELISA and NT antibody assay to analyze 246 human serum samples from the serum bank of the National Institute of Infectious Diseases (NIID) in Japan. RESULTS: The cut-off value of IgG-ELISA was determined at 0.20, based on the mean (- 0.075) and standard deviation (0.092) values using Japanese donors' sera. The sensitivity and the specificity of IgG-ELISA determined using 25 JCV-positive and 4 JCV-negative serum samples were 96 and 100%, respectively. Analysis of the 246 Japanese serum samples revealed that no specimen showed a higher value than the cut-off value of IgG-ELISA, and no sample tested positive by the NT antibody assay. CONCLUSIONS: Our results showed that JCV is not circulating significantly in Japan. To the best of our knowledge, this is the first report to demonstrate the seroprevalence of JCV in the general population in Japan.


Assuntos
Anticorpos Antivirais/imunologia , Vírus da Encefalite da Califórnia/imunologia , Encefalite da Califórnia/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Testes de Neutralização/métodos , Adolescente , Adulto , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Culicidae/virologia , Encefalite da Califórnia/virologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Adulto Jovem
11.
PLoS Negl Trop Dis ; 14(9): e0008621, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32970673

RESUMO

Ross River virus (RRV) is the most common and widespread arbovirus in Australia. Epidemiological models of RRV increase understanding of RRV transmission and help provide early warning of outbreaks to reduce incidence. However, RRV predictive models have not been systematically reviewed, analysed, and compared. The hypothesis of this systematic review was that summarising the epidemiological models applied to predict RRV disease and analysing model performance could elucidate drivers of RRV incidence and transmission patterns. We performed a systematic literature search in PubMed, EMBASE, Web of Science, Cochrane Library, and Scopus for studies of RRV using population-based data, incorporating at least one epidemiological model and analysing the association between exposures and RRV disease. Forty-three articles, all of high or medium quality, were included. Twenty-two (51.2%) used generalised linear models and 11 (25.6%) used time-series models. Climate and weather data were used in 27 (62.8%) and mosquito abundance or related data were used in 14 (32.6%) articles as model covariates. A total of 140 models were included across the articles. Rainfall (69 models, 49.3%), temperature (66, 47.1%) and tide height (45, 32.1%) were the three most commonly used exposures. Ten (23.3%) studies published data related to model performance. This review summarises current knowledge of RRV modelling and reveals a research gap in comparing predictive methods. To improve predictive accuracy, new methods for forecasting, such as non-linear mixed models and machine learning approaches, warrant investigation.


Assuntos
Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Animais , Austrália/epidemiologia , Clima , Culicidae/virologia , Previsões , Humanos , Incidência , Vírus do Rio Ross/isolamento & purificação , Tempo (Meteorologia)
12.
Arch Virol ; 165(12): 2903-2908, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32894348

RESUMO

A novel orbivirus (genus Orbivirus, family Reoviridae), designated Yonaguni orbivirus (YONOV), was isolated from bovine blood collected on a subtropical island of Japan in 2015. The YONOV genome (20,054 nucleotides in total) has a coding arrangement similar to those of mosquito-borne orbiviruses. YONOV has a close genetic relationship to mosquito-borne orbiviruses, especially to Mobuck virus (MBV), which was isolated in North America. However, YONOV and MBV share less than 74% nucleotide sequence identity in the major subcore protein (T2) coding sequence, which satisfies the criterion for species demarcation. It is still uncertain whether YONOV should be assigned to a novel species in the genus Orbivirus.


Assuntos
Genoma Viral , Orbivirus/classificação , Orbivirus/isolamento & purificação , Filogenia , Infecções por Reoviridae/veterinária , Proteínas Virais/genética , Animais , Bovinos/virologia , Culicidae/virologia , Japão , Fases de Leitura Aberta , Infecções por Reoviridae/virologia , Análise de Sequência de DNA
13.
PLoS Negl Trop Dis ; 14(8): e0008574, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853274

RESUMO

BACKGROUND: Shifts have occurred in the epidemiological characteristics of Japanese encephalitis (JE), extending from the molecular level to the population level. The aim of this study was to investigate the seroprevalence of JE neutralizing antibodies in healthy populations from different age groups in Zhejiang Province, and to conduct mosquito monitoring to evaluate the infection rate of Japanese encephalitis virus (JEV) among vectors, as well as the molecular characteristics of the E gene of isolated JEV strains. METHODOLOGY/PRINCIPAL FINDINGS: A total of 1190 sera samples were screened by a microseroneutralization test, including 429 infants (28d-11m) and 761 participants (2y-82y). For those under 1 year old, the geometric mean titers (GMTs) of the JE neutralizing antibody was 9.49 at birth and significantly declined as the age of month increased (r = -0.225, P<0.001). For those above 1-year old, seropositive proportions were higher in subjects aged 1-3 years old as well as ≥25 years old (65%-75%), and relatively lower in subjects aged between 4-25 years old (22%-55%). Four or more years after the 2nd dose of JEV-L (first dose administered at 8 months and the second at 2 years of age), the seropositive proportion decreased to 32.5%, and GMTs decreased to 8.08. A total of 87,201 mosquitoes were collected from livestock sheds in 6 surveillance sites during 2015-2018, from which 139 E gene sequences were successfully amplified. The annual infection rate according to bias-corrected maximum likelihood estimation of JEV in Culex tritaeniorhynchus was 1.56, 2.36, 5.65 and 1.77 per 1000, respectively. JEV strains isolated during 2015-2018 all belonged to Genotype I. The E gene of amplified 139 samples differed from the JEV-L vaccine strain at fourteen amino acid residues, including the eight key residues related to virulence and virus attenuation. No divergence was observed at the sites related to antigenicity. CONCLUSIONS/SIGNIFICANCE: Zhejiang Province was at a high risk of JE exposure due to relatively lower neutralizing antibody levels among the younger-aged population and higher infection rates of JEV in mosquitoes. Continuous, timely and full coverage of JE vaccination are essential, as well as the separation of human living areas and livestock shed areas. In addition, annual mosquito surveillance and periodic antibody level monitoring are important for providing evidence for improvement in JE vaccines and immunization schedules.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/virologia , Epidemiologia Molecular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Culex/virologia , Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/classificação , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/isolamento & purificação , Genes Virais/genética , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Mosquitos Vetores/virologia , Estudos Soroepidemiológicos , Adulto Jovem
14.
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
15.
Nature ; 585(7825): 414-419, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32641828

RESUMO

Zika virus (ZIKV) belongs to the family Flaviviridae, and is related to other viruses that cause human diseases. Unlike other flaviviruses, ZIKV infection can cause congenital neurological disorders and replicates efficiently in reproductive tissues1-3. Here we show that the envelope protein (E) of ZIKV is polyubiquitinated by the E3 ubiquitin ligase TRIM7 through Lys63 (K63)-linked polyubiquitination. Accordingly, ZIKV replicates less efficiently in the brain and reproductive tissues of Trim7-/- mice. Ubiquitinated E is present on infectious virions of ZIKV when they are released from specific cell types, and enhances virus attachment and entry into cells. Specifically, K63-linked polyubiquitin chains directly interact with the TIM1 (also known as HAVCR1) receptor of host cells, which enhances virus entry in cells as well as in brain tissue in vivo. Recombinant ZIKV mutants that lack ubiquitination are attenuated in human cells and in wild-type mice, but not in live mosquitoes. Monoclonal antibodies against K63-linked polyubiquitin specifically neutralize ZIKV and reduce viraemia in mice. Our results demonstrate that the ubiquitination of ZIKV E is an important determinant of virus entry, tropism and pathogenesis.


Assuntos
Ubiquitinação , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus , Zika virus/metabolismo , Zika virus/patogenicidade , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Encéfalo/metabolismo , Linhagem Celular , Culicidae/citologia , Culicidae/virologia , Endossomos/metabolismo , Feminino , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Masculino , Fusão de Membrana , Camundongos , Especificidade de Órgãos , Poliubiquitina/imunologia , Poliubiquitina/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Tropismo Viral , Viremia/imunologia , Viremia/prevenção & controle , Viremia/virologia , Replicação Viral , Zika virus/química , Zika virus/genética , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/virologia
16.
PLoS Negl Trop Dis ; 14(7): e0008450, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32628662

RESUMO

BACKGROUND: Zika virus (ZIKV) disease outbreaks have been occurring in South America since 2015, and has spread to North America. Because birth defects and cases of Guillain Barré have been associated with infection with ZIKV, this has drawn global attention. ZIKV is generally considered an Aedes-transmitted pathogen. The transmission of ZIKV through blood by Aedes mosquito bites has been recognized as the major transmission route. However, it is not clear whether there are other transmission routes that can cause viral infection in mosquitos. The aim of the present study is to describe the susceptibility of Armigeres subalbatus, which often develop in human waste lagoons, to ZIKV, through oral infection in adult mosquitoes and urine infection in larvae. METHODOLOGY/PRINCIPAL FINDINGS: Five-day-old female Ar. subalbatus ingested infectious blood meals containing ZIKV. After 4, 7, and 10 days of ingesting infectious blood meals, ZIKV could be detected in the midguts, salivary glands, ovaries, and collected saliva of mosquitoes. The ZIKV infection rate (IR) on day 10 reached 40% in salivary glands and 13% in saliva, indicating that these mosquitoes were able to transmit ZIKV. In addition, ZIKV infection was also discovered in mosquito ovaries, suggesting the possibility of vertical transmission of virus. Moreover, Ar. subalbatus transmitted ZIKV to infant mice bitten by infectious mosquitoes. In a second experiment, 1st-instar larvae of Ar. subalbatus were reared in water containing ZIKV and human urine. After pupation, pupae were placed in clean water and transferred to a mosquito cage for emergence. Although ZIKV RNA was detected in all of the larvae tested, ZIKV was not detected in the saliva of any adult Ar. subalbatus. Considering that there are more uncontrollable factors in nature than in the laboratory environment, the possibility that the virus is transmitted to adult mosquitoes via larvae is very small period. CONCLUSIONS/SIGNIFICANCE: Adult Ar. subalbatus could be infected with ZIKV and transmit ZIKV through mosquito bites. Therefore, in many rural areas in China and in undeveloped areas of other Asian countries, the management of human waste lagoons in the prevention and control of Zika disease should be considered. Corresponding adjustments and modifications should also be made in prevention and control strategies against ZIKV.


Assuntos
Culicidae/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Zika virus/fisiologia , Animais , Culicidae/crescimento & desenvolvimento , Culicidae/fisiologia , Feminino , Humanos , Larva/virologia , Camundongos , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/fisiologia , Saliva/virologia , Zika virus/genética , Zika virus/isolamento & purificação , Infecção por Zika virus/urina , Infecção por Zika virus/virologia
17.
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
18.
Sci Rep ; 10(1): 11915, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681089

RESUMO

This research addresses public speculation that SARS-CoV-2 might be transmitted by mosquitoes. The World Health Organization has stated "To date there has been no information nor evidence to suggest that the new coronavirus could be transmitted by mosquitoes". Here we provide the first experimental data to investigate the capacity of SARS-CoV-2 to infect and be transmitted by mosquitoes. Three widely distributed species of mosquito; Aedes aegypti, Ae. albopictus and Culex quinquefasciatus, representing the two most significant genera of arbovirus vectors that infect people, were tested. We demonstrate that even under extreme conditions, SARS-CoV-2 virus is unable to replicate in these mosquitoes and therefore cannot be transmitted to people even in the unlikely event that a mosquito fed upon a viremic host.


Assuntos
Betacoronavirus/fisiologia , Culicidae/virologia , Aedes/virologia , Animais , Betacoronavirus/isolamento & purificação , Chlorocebus aethiops , Culex/virologia , Insetos Vetores/virologia , Células Vero
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 Negl Trop Dis ; 14(6): e0008343, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32520944

RESUMO

St. Louis encephalitis virus (SLEV) is a flavivirus that circulates in an enzootic cycle between birds and mosquitoes and can also infect humans to cause febrile disease and sometimes encephalitis. Although SLEV is endemic to the United States, no activity was detected in California during the years 2004 through 2014, despite continuous surveillance in mosquitoes and sentinel chickens. In 2015, SLEV-positive mosquito pools were detected in Maricopa County, Arizona, concurrent with an outbreak of human SLEV disease. SLEV-positive mosquito pools were also detected in southeastern California and Nevada in summer 2015. From 2016 to 2018, SLEV was detected in mosquito pools throughout southern and central California, Oregon, Idaho, and Texas. To understand genetic relatedness and geographic dispersal of SLEV in the western United States since 2015, we sequenced four historical genomes (3 from California and 1 from Louisiana) and 26 contemporary SLEV genomes from mosquito pools from locations across the western US. Bayesian phylogeographic approaches were then applied to map the recent spread of SLEV. Three routes of SLEV dispersal in the western United States were identified: Arizona to southern California, Arizona to Central California, and Arizona to all locations east of the Sierra Nevada mountains. Given the topography of the Western United States, these routes may have been limited by mountain ranges that influence the movement of avian reservoirs and mosquito vectors, which probably represents the primary mechanism of SLEV dispersal. Our analysis detected repeated SLEV introductions from Arizona into southern California and limited evidence of year-to-year persistence of genomes of the same ancestry. By contrast, genetic tracing suggests that all SLEV activity since 2015 in central California is the result of a single persistent SLEV introduction. The identification of natural barriers that influence SLEV dispersal enhances our understanding of arbovirus ecology in the western United States and may also support regional public health agencies in implementing more targeted vector mitigation efforts to protect their communities more effectively.


Assuntos
Culicidae/virologia , Vírus da Encefalite de St. Louis/classificação , Vírus da Encefalite de St. Louis/genética , Encefalite de St. Louis/epidemiologia , Encefalite de St. Louis/virologia , Mosquitos Vetores/virologia , Animais , Teorema de Bayes , Surtos de Doenças , Genoma Viral , Humanos , Filogenia , Filogeografia , Estados Unidos/epidemiologia , Sequenciamento Completo do Genoma
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