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1.
Emerg Infect Dis ; 26(5): 1019-1021, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32097111

RESUMO

We conducted a cross-sectional survey of Crimean-Congo hemorrhagic fever virus (CCHFV) in dromedary camels and attached ticks at 3 locations in the United Arab Emirates. Results revealed a high prevalence of CCHFV-reactive antibodies in camels and viral RNA in ticks and camel serum, suggesting the virus is endemic in this country.

2.
Expert Rev Anti Infect Ther ; 18(2): 145-154, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31914833

RESUMO

Introduction: West Nile virus (WNV) is a mosquito-borne human and animal pathogen with nearly worldwide distribution. In Europe, the virus is endemic with seasonal regional outbreaks that have increased in frequency over the last 10 years. A massive outbreak occurred across southern and central Europe in 2018 with the number of confirmed human cases increasing up to 7.2-fold from the previous year, and expanding to include previously virus-free regions.Areas covered: This review focuses on potential causes that may explain the 2018 European WNV outbreak. We discuss the role genetic, ecological, and environmental aspects may have played in the increased activity during the 2018 transmission season, summarizing the latest epidemiological and virological publications.Expert opinion: Optimal environmental conditions, specifically increased temperature, were most likely responsible for the observed outbreak. Other factors cannot be ruled out due to limited available information, including factors that may influence host/vector abundance and contact. Europe will likely experience even larger-scale outbreaks in the coming years. Increased surveillance efforts should be implemented with a focus on early-warning detection methods, and large-scale host and vector surveys should continue to fill gaps in knowledge.

3.
Transbound Emerg Dis ; 67(3): 1189-1197, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31840920

RESUMO

We report details of the first seven equine cases of confirmed West Nile neuroinvasive disease in Austria. The cases presented during summer and autumn of 2016 (n = 2), 2017 (n = 3) and 2018 (n = 2). All horses showed gait abnormalities and 6 of 7 horses exhibited fasciculations and/or tremors, and we provide video recordings of these. Three horses also showed cranial nerve involvement. Following rapid improvement, three horses were discharged. Four horses were euthanized due to the severity of clinical signs and subjected to neuropathological examination. West Nile virus (WNV) lineage 2 nucleic acid was detected in 5 of 7 horses, and WNV-specific neutralizing antibodies in all 7 horses. In addition, serologic evidence of WNV infection was found in two out of fourteen in-contact horses. Horses may be considered a sentinel species for human WNV infections, integrating human and veterinary medicine and thus contributing to the one health concept.

4.
Parasit Vectors ; 12(1): 153, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944019

RESUMO

BACKGROUND: In the last 50 years, the United Arab Emirates (UAE) has experienced rapid population growth and urbanization. Urbanization is known to influence biodiversity, and there appears to be a link between the emergence of arboviruses and urban growth. Very little is known about the UAE mosquito species richness and dominant vectors. We performed a mosquito survey comparing peri-urban sites in Dubai and Al Ain to a protected, natural site in Fujairah emirate. We measured mosquito biodiversity and species composition, and screened mosquito pools for common arboviruses to measure arbovirus activity in the region. RESULTS: We report ten species of mosquitoes from the UAE, with highest species diversity in the natural site, a protected wadi near the eastern coast. The predominant mosquito was Culex perexiguus, and was associated with peri-urban habitats. The site with lowest mosquito species diversity but relatively high species richness was the peri-urban site of Al Ain Zoo, where we identified Bagaza virus and Barkedji virus, two flaviviruses, in pools of Cx. perexiguus. CONCLUSIONS: Decreased mosquito biodiversity was associated with increased levels of urbanization. The predominance of two species at peri-urban sites was related to the availability of their larval habitats. Arboviruses were associated with the presence of a single predominant mosquito species, Cx. perexiguus.


Assuntos
Arbovirus/isolamento & purificação , Culicidae , Animais , Arbovirus/classificação , Biodiversidade , Culicidae/classificação , Culicidae/virologia , Feminino , Masculino , Mosquitos Vetores/virologia , Emirados Árabes Unidos , Urbanização
5.
Parasit Vectors ; 12(1): 46, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665453

RESUMO

BACKGROUND: The emergence of Usutu virus (USUV) in Europe was first reported in Austria, 2001, and the virus has since spread to many European countries. Initial outbreaks are marked by a mass die-off of European blackbirds (Turdus merula) and other bird species. During outbreaks, the virus has been detected in pools of Culex pipiens mosquitoes, and these mosquitoes are probably the most important enzootic vectors. Beginning in 2017, a second wave of blackbird deaths associated with USUV was observed in eastern Austria; the affected areas expanded to the Austrian federal states of Styria in the south and to Upper Austria in the west in 2018. We sampled the potential vector population at selected sites of bird deaths in 2018 in order to identify infected mosquitoes. RESULTS: We detected USUV RNA in 16 out of 19 pools of Cx. pipiens/Cx. torrentium mosquitoes at sites of USUV-linked blackbird mortality in Linz and Graz, Austria. A disseminated virus infection was detected in individuals from selected pools, suggesting that Cx. pipiens form pipiens was the principal vector. In addition to a high rate of infected Cx. pipiens collected from Graz, a disseminated virus infection was detected in a pool of Aedes japonicus japonicus. CONCLUSIONS: We show herein that naturally-infected mosquitoes at foci of USUV activity are primarily Cx. pipiens form pipiens. In addition, we report the first natural infection of Ae. j. japonicus with USUV, suggesting that it may be involved in the epizootic transmission of USUV in Europe. Ae. j. japonicus is an invasive mosquito whose range is expanding in Europe.


Assuntos
Aedes/virologia , Culex/virologia , Infecções por Flavivirus/transmissão , Flavivirus/fisiologia , Mosquitos Vetores/virologia , Animais , Monitoramento Epidemiológico , Feminino , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/virologia , Humanos , Espécies Introduzidas
6.
Parasit Vectors ; 11(1): 456, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30081963

RESUMO

BACKGROUND: Uranotaenia unguiculata Edwards, 1913 is a species of mosquito (Diptera: Culicidae) native to central Europe. Recently a novel lineage of the West Nile virus (WNV-lineage 4c) was identified in pools of adult female Ur. unguiculata. To increase the body of knowledge about this species, various trapping methods were evaluated to determine the most efficient method for capturing adult female Ur. unguiculata. RESULTS: Sound traps collected equivalent numbers of female Ur. unguiculata as low-hanging light-baited downdraft traps. Hosts were identified as Pelophylax lessonae and P. ridibunda (Anura: Ranidae) species group frogs from the blood found in engorged females. In addition to confirming infection by WNV-lin. 4c, a potentially integrated flavivirus sequence was detected in male mosquitoes. A novel Alphamesonivirus 1 (Nidovirales: Mesoniviridae) was found to be widespread in the Ur. unguiculata population and is herein described. CONCLUSIONS: Efficient collection methods for Ur. unguiculata for arbovirus surveillance reflect mosquito questing behavior. Uranotaenia unguiculata targets frog species which call from the water, and it is likely that the novel WNV-lin. 4c is maintained in a frog-mosquito transmission cycle. The improved trapping methods listed here will assist future studies of the vector status of Ur. unguiculata for WNV and other arboviruses.


Assuntos
Anfíbios , Culicidae/fisiologia , Comportamento Alimentar , Som , Vírus/classificação , Animais , Culicidae/virologia , Feminino , Masculino , Fenômenos Fisiológicos Virais
7.
PLoS One ; 13(8): e0201307, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30067840

RESUMO

Four of the nine sigmodontine tribes have species that serve as reservoirs of rodent-borne hantaviruses (RBO-HV), few have been studied in any depth. Several viruses have been associated with human cases of hantavirus pulmonary syndrome often through peridomestic exposure. Jabora (JABV) and Juquitiba (JUQV), harbored by Akodon montensis and Oligoryzomys nigripes, respectively, are endemic and sympatric in the Reserva Natural de Bosque Mbaracayú (RNBM), Paraguay, a protected area of the Interior Atlantic Forest. Rodent communities were surveyed along a 30 km stretch of the RNBM in eight vegetation classifications (Low, High, Bamboo, Riparian and Liana Forests, Bamboo Understory, Cerrado, and Meadow/Grasslands). We collected 417 rodents from which 11 species were identified; Akodon montensis was the predominant species (72%; 95%CI: 64.7%-76.3%), followed by Hylaeamys megacephalus (15% (11.2%-18.2%)) and Oligoryzomys nigripes (9% (6.6%-12.4%)). We examined the statistical associations among habitat (vegetation class) type, rodent species diversity, population structure (age, sex, and weight), and prevalence of RBO-HV antibody and/or viral RNA (Ab/RNA) or characteristic Leishmania tail lesions. Ab/RNA positive rodents were not observed in Cerrado and Low Forest. A. montensis had an overall Ab/RNA prevalence of 7.7% (4.9%-11.3%) and O. nigripes had an overall prevalence of 8.6% (1.8%-23.1%). For A. montensis, the odds of being Ab/RNA positive in High Forest was 3.73 times of the other habitats combined. There was no significant difference among age classes in the proportion of Ab/RNA positive rodents overall (p = 0.66), however, all 11 RNA-positive individuals were adult. Sex and habitat had independent prognostic value for hantaviral Ab/RNA in the study population; age, presence of tail scar/lesion (19% of the rodents) and weight did not. Adjusting for habitat, female rodents had less risk of becoming infected. Importantly, these data suggest habitat preferences of two sympatric rodent reservoirs for two endemic hantaviruses and the importance of including habitat in models of species diversity and habitat fragmentation.


Assuntos
Reservatórios de Doenças/virologia , Infecções por Hantavirus/epidemiologia , Hantavirus/isolamento & purificação , Doenças dos Roedores/epidemiologia , Roedores/virologia , Animais , Reservatórios de Doenças/classificação , Ecossistema , Feminino , Infecções por Hantavirus/virologia , Síndrome Pulmonar por Hantavirus/epidemiologia , Síndrome Pulmonar por Hantavirus/virologia , Humanos , Masculino , Paraguai/epidemiologia , Doenças dos Roedores/virologia , Roedores/classificação
8.
Emerg Microbes Infect ; 7(1): 25, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29535293

RESUMO

The results of integrated human and veterinary surveillance for West Nile virus (WNV) infections in Austria during the transmission seasons 2015 and 2016 are shown. Altogether WNV nucleic acid was detected in 21 humans, horses, wild birds and mosquito pools. In detail: in four human clinical cases [two cases of West Nile fever (WNF) and two cases of West Nile neuroinvasive disease (WNND)]; eight blood donors [among 145,541 tested donations], of which three remained asymptomatic and five subsequently developed mild WNF; two horses with WNND, of which one recovered and one had to be euthanized; two wild birds [one goshawk and one falcon, both succumbed to WNND]; and five Culex pipiens mosquito pools. Compared to previous years the number of infections increased remarkably. All infections were recorded in the city of Vienna and neighboring regions of Lower Austria. Sixteen coding-complete WNV sequences were established which were closely related to each other and to other Austrian, Czech and Italian viruses, all belonging to the Central/Southern European cluster of WNV sublineage 2d. However, several genetically slightly different WNV strains seem to co-circulate in the same area, as demonstrated by phylogenetic analysis. Based on detailed sequence analysis, all newly discovered Austrian WNV strains had the potential to cause neurological disease, but no correlation was found between severity of disease and the analyzed genetic virulence/neuroinvasiveness markers. Results of integrated human-animal-vector surveillance presented in this paper provide a comprehensive description of WNV activity in the region and will facilitate proactive public health measures to prevent or mitigate potential outbreaks.


Assuntos
Doenças das Aves/virologia , Culex/virologia , Doenças dos Cavalos/virologia , Mosquitos Vetores/virologia , Febre do Nilo Ocidental/veterinária , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Áustria/epidemiologia , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Aves/virologia , Culex/fisiologia , Cães , Monitoramento Epidemiológico , Feminino , Doenças dos Cavalos/sangue , Doenças dos Cavalos/epidemiologia , Cavalos/virologia , Humanos , Masculino , Mosquitos Vetores/fisiologia , Filogenia , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genética
9.
J Insect Sci ; 17(5)2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29117370

RESUMO

Flies in the family Corethrellidae Edwards 1932 (Diptera) are known to be attracted to the mating calls of male frogs. For the first time, the hosts of corethrellids were identified to species by analyzing bloodmeals taken from resting female flies. A portion of the cytochrome b gene was amplified and sequenced from blood-engorged flies using vertebrate-specific primers. The flies were collected over 6 yr at two locations in the southeastern United States from resting boxes and natural resting sites (rodent burrows). Potential host abundance focused on frog surveillance, and estimation relied on visual encounters, passive trapping (artificial refugia), and call surveys. This study confirms that corethrellids take blood from tree frogs (Hylidae); however, it was found that true frogs (Lithobates Fitzinger 1843 (Ranidae: Anura) sp.) were the principal host selected by Corethrella brakeleyi (Coquillett 1902) (~73% of identified bloodmeals). These preliminary data suggest that host selection of Corethrella Freeman 1962 sp. is not necessarily correlated with host calling abundance.


Assuntos
Anuros/parasitologia , Dípteros/fisiologia , Animais , Comportamento Alimentar , Feminino , Especificidade de Hospedeiro , Masculino
10.
Front Immunol ; 8: 550, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553293

RESUMO

Neutrophils are immune cells that are well known to be present during many types of lung diseases associated with acute respiratory distress syndrome (ARDS) and may contribute to acute lung injury. Neutrophils are poorly studied with respect to viral infection, and specifically to respiratory viral disease. Influenza A virus (IAV) infection is the cause of a respiratory disease that poses a significant global public health concern. Influenza disease presents as a relatively mild and self-limiting although highly pathogenic forms exist. Neutrophils increase in the respiratory tract during infection with mild seasonal IAV, moderate and severe epidemic IAV infection, and emerging highly pathogenic avian influenza (HPAI). During severe influenza pneumonia and HPAI infection, the number of neutrophils in the lower respiratory tract is correlated with disease severity. Thus, comparative analyses of the relationship between IAV infection and neutrophils provide insights into the relative contribution of host and viral factors that contribute to disease severity. Herein, we review the contribution of neutrophils to IAV disease pathogenesis and to other respiratory virus infections.

11.
PLoS Pathog ; 12(12): e1006104, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27959961

RESUMO

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVΔnef antigenic load. In conclusion, maturation of SIVΔnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Citometria de Fluxo , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Macaca mulatta , Reação em Cadeia da Polimerase em Tempo Real , Vagina/imunologia , Vagina/virologia , Carga Viral
12.
J Virol Methods ; 236: 252-257, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27491341

RESUMO

The development of reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assays are described herein for the detection of two orthobunyaviruses (Bunyaviridae), which represent the two main serogroups found in mosquitoes in Central Europe. The RT-LAMP assays were optimized for the detection of Tahyna virus (a California encephalitis group virus found in Aedes sp or Ochlerotatus sp mosquitoes) and Batai virus (also called Calovo virus, a Bunyamwera group virus found in Anopheles maculipennis s.l. mosquitoes) nucleic acid using endemic European virus isolates. The sensitivity of the RT-LAMP assays was determined to be comparable to that of conventional tests, with a limit of detection<0.1 pfu per reaction. The assays can be performed in 60min under isothermal conditions using very simple equipment. Furthermore, it was possible to proceed with the assays without nucleic acid extraction, albeit at a 100-fold loss of sensitivity. The RT-LAMP assays are a sensitive, cost-efficient method for both arbovirus surveillance as well as diagnostic laboratories to detect the presence of these endemic orthobunyaviruses.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Orthobunyavirus/classificação , Orthobunyavirus/isolamento & purificação , RNA Viral/genética , Transcrição Reversa , Animais , Análise Custo-Benefício , Europa (Continente) , Orthobunyavirus/genética , Sensibilidade e Especificidade , Fatores de Tempo
13.
Med Phys ; 42(7): 3896-910, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26133591

RESUMO

PURPOSE: To develop an automated pulmonary image analysis framework for infectious lung diseases in small animal models. METHODS: The authors describe a novel pathological lung and airway segmentation method for small animals. The proposed framework includes identification of abnormal imaging patterns pertaining to infectious lung diseases. First, the authors' system estimates an expected lung volume by utilizing a regression function between total lung capacity and approximated rib cage volume. A significant difference between the expected lung volume and the initial lung segmentation indicates the presence of severe pathology, and invokes a machine learning based abnormal imaging pattern detection system next. The final stage of the proposed framework is the automatic extraction of airway tree for which new affinity relationships within the fuzzy connectedness image segmentation framework are proposed by combining Hessian and gray-scale morphological reconstruction filters. RESULTS: 133 CT scans were collected from four different studies encompassing a wide spectrum of pulmonary abnormalities pertaining to two commonly used small animal models (ferret and rabbit). Sensitivity and specificity were greater than 90% for pathological lung segmentation (average dice similarity coefficient > 0.9). While qualitative visual assessments of airway tree extraction were performed by the participating expert radiologists, for quantitative evaluation the authors validated the proposed airway extraction method by using publicly available EXACT'09 data set. CONCLUSIONS: The authors developed a comprehensive computer-aided pulmonary image analysis framework for preclinical research applications. The proposed framework consists of automatic pathological lung segmentation and accurate airway tree extraction. The framework has high sensitivity and specificity; therefore, it can contribute advances in preclinical research in pulmonary diseases.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Pneumopatias/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Modelos Animais de Doenças , Compostos Férricos , Vírus da Influenza A Subtipo H1N1 , Estudos Longitudinais , Medidas de Volume Pulmonar/métodos , Aprendizado de Máquina , Infecções por Orthomyxoviridae/diagnóstico por imagem , Coelhos , Tuberculose Pulmonar/diagnóstico por imagem
14.
J Virol ; 89(17): 8733-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26063430

RESUMO

UNLABELLED: Infection of the lower respiratory tract by influenza A viruses results in increases in inflammation and immune cell infiltration in the lung. The dynamic relationships among the lung microenvironments, the lung, and systemic host responses during infection remain poorly understood. Here we used extensive systematic histological analysis coupled with live imaging to gain access to these relationships in ferrets infected with the 2009 H1N1 pandemic influenza A virus (H1N1pdm virus). Neutrophil levels rose in the lungs of H1N1pdm virus-infected ferrets 6 h postinfection and became concentrated at areas of the H1N1pdm virus-infected bronchiolar epithelium by 1 day postinfection (dpi). In addition, neutrophil levels were increased throughout the alveolar spaces during the first 3 dpi and returned to baseline by 6 dpi. Histochemical staining revealed that neutrophil infiltration in the lungs occurred in two waves, at 1 and 3 dpi, and gene expression within microenvironments suggested two types of neutrophils. Specifically, CCL3 levels, but not CXCL8/interleukin 8 (IL-8) levels, were higher within discrete lung microenvironments and coincided with increased infiltration of neutrophils into the lung. We used live imaging of ferrets to monitor host responses within the lung over time with [(18)F]fluorodeoxyglucose (FDG). Sites in the H1N1pdm virus-infected ferret lung with high FDG uptake had high levels of proliferative epithelium. In summary, neutrophils invaded the H1N1pdm virus-infected ferret lung globally and focally at sites of infection. Increased neutrophil levels in microenvironments did not correlate with increased FDG uptake; hence, FDG uptake may reflect prior infection and inflammation of lungs that have experienced damage, as evidenced by bronchial regeneration of tissues in the lungs at sites with high FDG levels. IMPORTANCE: Severe influenza disease is characterized by an acute infection of the lower airways that may progress rapidly to organ failure and death. Well-developed animal models that mimic human disease are essential to understanding the complex relationships of the microenvironment, organ, and system in controlling virus replication, inflammation, and disease progression. Employing the ferret model of H1N1pdm virus infection, we used live imaging and comprehensive histological analyses to address specific hypotheses regarding spatial and temporal relationships that occur during the progression of infection and inflammation. We show the general invasion of neutrophils at the organ level (lung) but also a distinct pattern of localized accumulation within the microenvironment at the site of infection. Moreover, we show that these responses were biphasic within the lung. Finally, live imaging revealed an early and sustained host metabolic response at sites of infection that may reflect damage and repair of tissues in the lungs.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Infecções por Orthomyxoviridae/imunologia , Infecções Respiratórias/imunologia , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Quimiocina CCL3/genética , Quimiocina CCL3/imunologia , Feminino , Furões/imunologia , Furões/virologia , Fluordesoxiglucose F18 , Expressão Gênica , Vírus da Influenza A Subtipo H1N1/patogenicidade , Interleucina-8/imunologia , Pulmão/citologia , Pulmão/imunologia , Pulmão/virologia , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Tomografia por Emissão de Pósitrons , Infecções Respiratórias/veterinária , Infecções Respiratórias/virologia
15.
Viruses ; 5(11): 2704-20, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24217424

RESUMO

Andes virus, ANDV, harbored by wild rodents, causes the highly lethal hantavirus pulmonary syndrome (HPS) upon transmission to humans resulting in death in 30% to 50% of the cases. As there is no treatment for this disease, we systematically tested the efficacy of ribavirin in vitro and in an animal model. In vitro assays confirmed antiviral activity and determined that the most effective doses were 40 µg/mL and above. We tested three different concentrations of ribavirin for their capability to prevent HPS in the ANDV hamster model following an intranasal challenge. While the highest level of ribavirin (200 mg/kg) was toxic to the hamster, both the middle (100 mg/kg) and the lowest concentration (50 mg/kg) prevented HPS in hamsters without toxicity. Specifically, 8 of 8 hamsters survived intranasal challenge for both of those groups whereas 7 of 8 PBS control-treated animals developed lethal HPS. Further, we report that administration of ribavirin at 50 mg/kg/day starting on days 6, 8, 10, or 12 post-infection resulted in significant protection against HPS in all groups. Administration of ribavirin at 14 days post-infection also provided a significant level of protection against lethal HPS. These data provide in vivo evidence supporting the potential use of ribavirin as a post-exposure treatment to prevent HPS after exposure by the respiratory route.


Assuntos
Antivirais/administração & dosagem , Síndrome Pulmonar por Hantavirus/prevenção & controle , Hantavirus/efeitos dos fármacos , Ribavirina/administração & dosagem , Animais , Antivirais/efeitos adversos , Cricetinae , Modelos Animais de Doenças , Feminino , Hantavirus/fisiologia , Síndrome Pulmonar por Hantavirus/tratamento farmacológico , Síndrome Pulmonar por Hantavirus/virologia , Humanos , Mesocricetus , Cavidade Nasal/virologia , Ribavirina/efeitos adversos
16.
PLoS One ; 8(11): e78912, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244384

RESUMO

Replication, cell tropism and the magnitude of the host's antiviral immune response each contribute to the resulting pathogenicity of influenza A viruses (IAV) in humans. In contrast to seasonal IAV in human cases, the 2009 H1N1 pandemic IAV (H1N1pdm) shows a greater tropism for infection of the lung similar to H5N1. We hypothesized that host responses during infection of well-differentiated, primary human bronchial epithelial cells (wd-NHBE) may differ between seasonal (H1N1 A/BN/59/07) and H1N1pdm isolates from a fatal (A/KY/180/10) and nonfatal (A/KY/136/09) case. For each virus, the level of infectious virus and host response to infection (gene expression and apical/basal cytokine/chemokine profiles) were measured in wd-NHBE at 8, 24, 36, 48 and 72 hours post-infection (hpi). At 24 and 36 hpi, KY/180 showed a significant, ten-fold higher titer as compared to the other two isolates. Apical cytokine/chemokine levels of IL-6, IL-8 and GRO were similar in wd-NHBE cells infected by each of these viruses. At 24 and 36 hpi, NHBE cells had greater levels of pro-inflammatory cytokines including IFN-α, CCL2, TNF-α, and CCL5, when infected by pandemic viruses as compared with seasonal. Polarization of IL-6 in wd-NHBE cells was greatest at 36 hpi for all isolates. Differential polarized secretion was suggested for CCL5 across isolates. Despite differences in viral titer across isolates, no significant differences were observed in KY/180 and KY/136 gene expression intensity profiles. Microarray profiles of wd-NHBE cells diverged at 36 hpi with 1647 genes commonly shared by wd-NHBE cells infected by pandemic, but not seasonal isolates. Significant differences were observed in cytokine signaling, apoptosis, and cytoskeletal arrangement pathways. Our studies revealed differences in temporal dynamics and basal levels of cytokine/chemokine responses of wd-NHBE cells infected with each isolate; however, wd-NHBE cell gene intensity profiles were not significantly different between the two pandemic isolates suggesting post-transcriptional or later differences in viral-host interactions.


Assuntos
Células Epiteliais/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Pandemias , Mucosa Respiratória/imunologia , Animais , Citocinas/imunologia , Cães , Células Epiteliais/patologia , Células Epiteliais/virologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/patologia , Células Madin Darby de Rim Canino , Análise de Sequência com Séries de Oligonucleotídeos , Células PC12 , Ratos , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia
17.
J Virol ; 87(20): 10997-1007, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23903835

RESUMO

In vitro, ribavirin acts as a lethal mutagen in Hantaan virus (HTNV)-infected Vero E6 cells, resulting in an increased mutation load and viral population extinction. In this study, we asked whether ribavirin treatment in the lethal, suckling mouse model of HTNV infection would act similarly. The HTNV genomic RNA (vRNA) copy number and infectious virus were measured in lungs of untreated and ribavirin-treated mice. In untreated, HTNV-infected mice, the vRNA copy number increased for 10 days postinfection (dpi) and thereafter remained constant through 26 dpi. Surprisingly, in ribavirin-treated, HTNV-infected mice, vRNA levels were similar to those in untreated mice between 10 and 26 dpi. Infectious virus levels, however, were different: in ribavirin-treated mice, the amount of infectious HTNV was significantly decreased relative to that in untreated mice, suggesting that ribavirin reduced the specific infectivity of the virus (amount of infectious virus produced per vRNA copy). Mutational analysis revealed a ribavirin-associated elevation in mutation frequency in HTNV vRNA similar to that previously reported in vitro. Codon-based analyses of rates of nonsynonymous (dN) and synonymous (dS) substitutions in the S segment revealed a positive selection for codons within the HTNV N protein gene in the ribavirin-treated vRNA population. In contrast, the vRNA population in untreated, HTNV-infected mice showed a lower level of diversity, reflecting purifying selection for the wild-type genome. In summary, these experiments show two different evolutionary paths that Hantavirus may take during infection in a lethal murine model of disease, as well as the importance of the in vivo host environment in the evolution of the virus, which was not apparent in our prior in vitro model system.


Assuntos
Antivirais/administração & dosagem , Evolução Molecular , Vírus Hantaan/genética , Febre Hemorrágica com Síndrome Renal/virologia , RNA Viral/genética , Ribavirina/administração & dosagem , Animais , Animais Recém-Nascidos , Análise Mutacional de DNA , Modelos Animais de Doenças , Feminino , Vírus Hantaan/isolamento & purificação , Febre Hemorrágica com Síndrome Renal/tratamento farmacológico , Pulmão/virologia , Camundongos , Camundongos Endogâmicos ICR , Taxa de Mutação , Gravidez , Análise de Sequência de DNA , Carga Viral
18.
PLoS One ; 8(2): e56602, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23441208

RESUMO

To capture the possible genotypic and phenotypic differences of the 2009 influenza A virus H1N1 pandemic (H1N1pdm) strains circulating in adult hospitalized patients, we isolated and sequenced nine H1N1pdm viruses from patients hospitalized during 2009-2010 with severe influenza pneumonia in Kentucky. Each viral isolate was characterized in mice along with two additional H1N1 pandemic strains and one seasonal strain to assess replication and virulence. All isolates showed similar levels of replication in nasal turbinates and lung, but varied in their ability to cause morbidity. Further differences were identified in cytokine and chemokine responses. IL-6 and KC were expressed early in mice infected with strains associated with higher virulence. Strains that showed lower pathogenicity in mice had greater IFNγ, MIG, and IL-10 responses. A principal component analysis (PCA) of the cytokine and chemokine profiles revealed 4 immune response phenotypes that correlated with the severity of disease. A/KY/180/10, which showed the greatest virulence with a rapid onset of disease progression, was compared in additional studies with A/KY/136/09, which showed low virulence in mice. Analyses comparing a low (KY/136) versus a high (KY/180) virulent isolate showed a significant difference in the kinetics of infection within the lower respiratory tract and immune responses. Notably by 4 DPI, virus titers within the lung, bronchoalveolar lavage fluid (BALf), and cells within the BAL (BALc) revealed that the KY/136 replicated in BALc, while KY/180 replication persisted in lungs and BALc. In summary, our studies suggest four phenotypic groups based on immune responses that result in different virulence outcomes in H1N1pdm isolates with a high degree of genetic similarity. In vitro studies with two of these isolates suggested that the more virulent isolate, KY/180, replicates productively in macrophages and this may be a key determinant in tipping the response toward a more severe disease progression.


Assuntos
Vírus da Influenza A Subtipo H1N1/fisiologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Fenótipo , Adulto , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linhagem Celular , Citocinas/metabolismo , Feminino , Genes Virais , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/imunologia , Influenza Humana/virologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Macrófagos/imunologia , Macrófagos/virologia , Masculino , Camundongos , Pessoa de Meia-Idade , Infecções por Orthomyxoviridae/mortalidade , Análise de Componente Principal , Virulência , Replicação Viral , Perda de Peso
19.
PLoS One ; 7(7): e40094, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22911695

RESUMO

Molecular imaging has gained attention as a possible approach for the study of the progression of inflammation and disease dynamics. Herein we used [(18)F]-2-deoxy-2-fluoro-D-glucose ([(18)F]-FDG) as a radiotracer for PET imaging coupled with CT (FDG-PET/CT) to gain insight into the spatiotemporal progression of the inflammatory response of ferrets infected with a clinical isolate of a pandemic influenza virus, H1N1 (H1N1pdm). The thoracic regions of mock- and H1N1pdm-infected ferrets were imaged prior to infection and at 1, 2, 3 and 6 days post-infection (DPI). On 1 DPI, FDG-PET/CT imaging revealed areas of consolidation in the right caudal lobe which corresponded with elevated [(18)F]-FDG uptake (maximum standardized uptake values (SUVMax), 4.7-7.0). By days 2 and 3, consolidation (CT) and inflammation ([(18)F]-FDG) appeared in the left caudal lobe. By 6 DPI, CT images showed extensive areas of patchy ground-glass opacities (GGO) and consolidations with the largest lesions having high SUVMax (6.0-7.6). Viral shedding and replication were detected in most nasal, throat and rectal swabs and nasal turbinates and lungs on 1, 2 and 3 DPI, but not on day 7, respectively. In conclusion, molecular imaging of infected ferrets revealed a progressive consolidation on CT with corresponding [(18)F]-FDG uptake. Strong positive correlations were measured between SUVMax and bronchiolitis-related pathologic scoring (Spearman's ρ = 0.75). Importantly, the extensive areas of patchy GGO and consolidation seen on CT in the ferret model at 6 DPI are similar to that reported for human H1N1pdm infections. In summary, these first molecular imaging studies of lower respiratory infection with H1N1pdm show that FDG-PET can give insight into the spatiotemporal progression of the inflammation in real-time.


Assuntos
Vírus da Influenza A Subtipo H1N1/fisiologia , Imagem Molecular , Imagem Multimodal , Infecções por Orthomyxoviridae/diagnóstico , Pneumonia/diagnóstico , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Animais , Progressão da Doença , Feminino , Furões/virologia , Fluordesoxiglucose F18 , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Pulmão/patologia , Pulmão/virologia , Nariz/virologia , Infecções por Orthomyxoviridae/virologia , Pandemias , Pneumonia/virologia , Replicação Viral , Eliminação de Partículas Virais
20.
PLoS One ; 7(7): e40743, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808249

RESUMO

Different respiratory viruses induce virus-specific gene expression in the host. Recent evidence, including those presented here, suggests that genetically related isolates of influenza virus induce strain-specific host gene regulation in several animal models. Here, we identified systemic strain-specific gene expression signatures in ferrets infected with pandemic influenza A/California/07/2009, A/Mexico/4482/2009 or seasonal influenza A/Brisbane/59/2007. Using uncorrelated shrunken centroid classification, we were able to accurately identify the infecting influenza strain with a combined gene expression profile of 10 selected genes, independent of the severity of disease. Another gene signature, consisting of 7 genes, could classify samples based on lung pathology. Furthermore, we identified a gene expression profile consisting of 31 probes that could classify samples based on both strain and severity of disease. Thus, we show that expression-based analysis of non-infected tissue enables distinction between genetically related influenza viruses as well as lung pathology. These results open for development of alternative tools for influenza diagnostics.


Assuntos
Furões/virologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Vírus da Influenza A Subtipo H1N1/genética , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Animais , Análise por Conglomerados , Furões/imunologia , Regulação da Expressão Gênica , Vírus da Influenza A Subtipo H1N1/classificação , Pulmão/patologia , Pulmão/virologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia
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