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1.
Viruses ; 16(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675940

RESUMO

West Nile Virus (WNV) and Usutu Virus (USUV) are both neurotropic mosquito-borne viruses belonging to the Flaviviridae family. These closely related viruses mainly follow an enzootic cycle involving mosquitoes as vectors and birds as amplifying hosts, but humans and other mammals can also be infected through mosquito bites. WNV was first identified in Uganda in 1937 and has since spread globally, notably in Europe, causing periodic outbreaks associated with severe cases of neuroinvasive diseases such as meningitis and encephalitis. USUV was initially isolated in 1959 in Swaziland and has also spread to Europe, primarily affecting birds and having a limited impact on human health. There has been a recent expansion of these viruses' geographic range in Europe, facilitated by factors such as climate change, leading to increased human exposure. While sharing similar biological traits, ecology, and epidemiology, there are significant distinctions in their pathogenicity and their impact on both human and animal health. While WNV has been more extensively studied and is a significant public health concern in many regions, USUV has recently been gaining attention due to its emergence in Europe and the diversity of its circulating lineages. Understanding the pathophysiology, ecology, and transmission dynamics of these viruses is important to the implementation of effective surveillance and control measures. This perspective provides a brief overview of the current situation of these two viruses in Europe and outlines the significant challenges that need to be addressed in the coming years.


Assuntos
Aves , Infecções por Flavivirus , Flavivirus , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Europa (Continente)/epidemiologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/fisiologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Humanos , Flavivirus/classificação , Flavivirus/genética , Flavivirus/patogenicidade , Flavivirus/isolamento & purificação , Flavivirus/fisiologia , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/virologia , Infecções por Flavivirus/transmissão , Infecções por Flavivirus/veterinária , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Febre do Nilo Ocidental/transmissão , Aves/virologia , Culicidae/virologia , Mosquitos Vetores/virologia , Surtos de Doenças
3.
BMC Ophthalmol ; 24(1): 160, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600458

RESUMO

BACKGROUND: To describe a case of bilateral multifocal chorioretinitis as the only presentation of acute West Nile virus (WNV) infection in the absence of neurological involvement. CASE PRESENTATION: A 78-year-old Italian woman was admitted to our emergency department because she noticed blurry vision in both eyes. She did not report fever, fatigue, or neurological symptoms in the last few days. Multimodal imaging showed the presence of bilateral hyperfluorescent lesions with a linear distribution, that corresponded to hypocyanescent spots on indocyanine green angiography. Antibody serology showed the presence of IgM antibodies, IgG antibodies, and ribonucleic acid (RNA) for WNV. Magnetic resonance imaging (MRI) of the brain ruled out central nervous system involvement. Three months later, the patient reported spontaneous resolution of her symptoms and remission of the chorioretinal infiltrates. CONCLUSIONS: In endemic areas, it is important to think of acute WNV infection as an explanatory etiology in cases of multifocal chorioretinitis, even without neurological involvement.


Assuntos
Coriorretinite , Infecções Oculares Virais , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Humanos , Feminino , Idoso , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/epidemiologia , Infecções Oculares Virais/diagnóstico , Coriorretinite/etiologia , Corpo Vítreo/patologia , Anticorpos Antivirais
4.
Emerg Microbes Infect ; 13(1): 2348510, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38686545

RESUMO

West Nile virus (WNV) is the most widely distributed mosquito-borne flavivirus in the world. This flavivirus can infect humans causing in some cases a fatal neurological disease and birds are the main reservoir hosts. WNV is endemic in Spain, and human cases have been reported since 2004. Although different studies analyse how climatic conditions can affect the dynamics of WNV infection, very few use long-term datasets. Between 2003 and 2020 a total of 2,724 serum samples from 1,707 common coots (Fulica atra) were analysed for the presence of WNV-specific antibodies. Mean (SD) annual seroprevalence was 24.67% (0.28) but showed high year-to-year variations ranging from 5.06% (0.17) to 68.89% (0.29). Significant positive correlations (p < 0.01) were observed between seroprevalence and maximum winter temperature and mean spring temperature. The unprecedented WNV outbreak in humans in the south of Spain in 2020 was preceded by a prolonged period of escalating WNV local circulation. Given current global and local climatic trends, WNV circulation is expected to increase in the next decades. This underscores the necessity of implementing One Health approaches to reduce the risk of future WNV outbreaks in humans. Our results suggest that higher winter and spring temperatures may be used as an early warning signal of more intense WNV circulation among wildlife in Spain, and consequently highlight the need of more intense vector control and surveillance in human inhabited areas.


Assuntos
Anticorpos Antivirais , Estações do Ano , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Espanha/epidemiologia , Vírus do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/isolamento & purificação , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Febre do Nilo Ocidental/veterinária , Animais , Estudos Soroepidemiológicos , Humanos , Anticorpos Antivirais/sangue , Surtos de Doenças , Temperatura
5.
Viruses ; 16(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38543707

RESUMO

BACKGROUND: Viral meningitis/encephalitis (ME) is a rare but potentially harmful disease. The prompt identification of the respective virus is important to guide not only treatment but also potential public health countermeasures. However, in about 40% of cases, no virus is identified despite an extensive diagnostic workup. The aim of the present study was to analyze demographic, seasonal, and routine cerebrospinal fluid (CSF) parameters in cases of viral ME and assess their utility for the prediction of the causative virus. METHODS: Demographic data, season, and routine CSF parameters (total leucocytes, CSF cell differentiation, age-adjusted CSF/serum albumin ratio, and total immunoglobulin ratios) were retrospectively assessed in cases of viral ME. RESULTS: In total, 156 cases of acute viral ME (74 female, median age 40.0 years) were treated at a tertiary-care hospital in Germany. Specific viral infections were detected in 93 (59.6%) cases. Of these, 14 (9.0%) cases were caused by herpes simplex virus (HSV), 36 (23.1%) by varicella-zoster virus (VZV), 27 (17.3%) by enteroviruses, 9 (5.8%) by West Nile virus (WNV), and 7 (4.5%) by other specific viruses. Additionally, 64 (41.0%) cases of ME of unknown viral etiology were diagnosed. Cases of WNV ME were older, predominantly male, showed a severe disruption of the blood-CSF-barrier, a high proportion of neutrophils in CSF, and an intrathecal total immunoglobulin M synthesis in the first CSF sample. In a multinominal logistic regression analysis, the accuracy of these CSF parameters together with age and seasonality was best for the prediction of WNV (87.5%), followed by unknown viral etiology (66.7%), VZV (61.8%), and enteroviruses (51.9%). CONCLUSIONS: Cases with WNV ME showed a specific pattern of routine CSF parameters and demographic data that allowed for their identification with good accuracy. These findings might help to guide the diagnostic workup in cases with viral ME, in particular allowing the timely identification of cases with ME due to WNV.


Assuntos
Encefalite Viral , Infecções por Enterovirus , Meningite Viral , Vírus , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Masculino , Humanos , Feminino , Adulto , Estudos Retrospectivos , Anticorpos Antivirais , Febre do Nilo Ocidental/diagnóstico , Meningite Viral/diagnóstico , Herpesvirus Humano 3
6.
JAMA Netw Open ; 7(3): e244294, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38546642

RESUMO

Importance: West Nile virus (WNV) is the leading cause of human arboviral disease in the US, peaking during summer. The incidence of WNV, including its neuroinvasive form (NWNV), is increasing, largely due to the expanding distribution of its vector, the Culex mosquito, and climatic changes causing heavy monsoon rains. However, the distinct characteristics and outcomes of NWNV in individuals who are immunosuppressed (IS) and individuals who are not IS remain underexplored. Objective: To describe and compare clinical and radiographic features, treatment responses, and outcomes of NWNV infection in individuals who are IS and those who are not IS. Design, Setting, and Participants: This retrospective cohort study used data from the Mayo Clinic Hospital system collected from July 2006 to December 2021. Participants were adult patients (age ≥18 years) with established diagnosis of NWNV infection. Data were analyzed from May 12, 2020, to July 20, 2023. Exposure: Immunosuppresion. Main Outcomes and Measures: Outcomes of interest were clinical and radiographic features and 90-day mortality among patients with and without IS. Results: Of 115 participants with NWNV infection (mean [SD] age, 64 [16] years; 75 [66%] male) enrolled, 72 (63%) were not IS and 43 (37%) were IS. Neurologic manifestations were meningoencephalitis (98 patients [85%]), encephalitis (10 patients [9%]), and myeloradiculitis (7 patients [6%]). Patients without IS, compared with those with IS, more frequently reported headache (45 patients [63%] vs 18 patients [42%]) and myalgias (32 patients [44%] vs 9 patients [21%]). In contrast, patients with IS, compared with those without, had higher rates of altered mental status (33 patients [77%] vs 41 patients [57%]) and myoclonus (8 patients [19%] vs 8 patients [4%]). Magnetic resonance imaging revealed more frequent thalamic T2 fluid-attenuated inversion recovery hyperintensities in individuals with IS than those without (4 patients [11%] vs 0 patients). Individuals with IS had more severe disease requiring higher rates of intensive care unit admission (26 patients [61%] vs 24 patients [33%]) and mechanical ventilation (24 patients [56%] vs 22 patients [31%]). The 90-day all-cause mortality rate was higher in the patients with IS compared with patients without IS (12 patients [28%] vs 5 patients [7%]), and this difference in mortality persisted after adjusting for Glasgow Coma Scale score (adjusted hazard ratio, 2.22; 95% CI, 1.07-4.27; P = .03). Individuals with IS were more likely to receive intravenous immunoglobulin than individuals without IS (12 individuals [17%] vs 24 individuals [56%]), but its use was not associated with survival (hazard ratio, 1.24; 95% CI, 0.50-3.09; P = .64). Conclusions and Relevance: In this cohort study of individuals with NWNV infection, individuals with IS had a higher risk of disease complications and poor outcomes than individuals without IS, highlighting the need for innovative and effective therapies to improve outcomes in this high-risk population.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Adulto , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Adolescente , Feminino , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/epidemiologia , Estudos de Coortes , Estudos Retrospectivos , Mosquitos Vetores
7.
Parasit Vectors ; 17(1): 156, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532512

RESUMO

BACKGROUND: Mosquito-borne diseases are on the rise. While climatic factors have been linked to disease occurrences, they do not explain the non-random spatial distribution in disease outbreaks. Landscape-related factors, such as vegetation structure, likely play a crucial but hitherto unquantified role. METHODS: We explored how three critically important factors that are associated with mosquito-borne disease outbreaks: microclimate, mosquito abundance and bird communities, vary at the landscape scale. We compared the co-occurrence of these three factors in two contrasting habitat types (forest versus grassland) across five rural locations in the central part of the Netherlands between June and September 2021. RESULTS: Our results show that forest patches provide a more sheltered microclimate, and a higher overall abundance of birds. When accounting for differences in landscape characteristics, we also observed that the number of mosquitoes was higher in isolated forest patches. CONCLUSIONS: Our findings indicate that, at the landscape scale, variation in tree cover coincides with suitable microclimate and high Culex pipiens and bird abundance. Overall, these factors can help understand the non-random spatial distribution of mosquito-borne disease outbreaks.


Assuntos
Culex , Culicidae , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Microclima , Aves , Mosquitos Vetores
8.
Parasit Vectors ; 17(1): 140, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500161

RESUMO

BACKGROUND: Different mosquito control strategies have been implemented to mitigate or prevent mosquito-related public health situations. Modern mosquito control largely relies on multiple approaches, including targeted, specific treatments. Given this, it is becoming increasingly important to supplement these activities with rapid and mobile diagnostic capacities for mosquito-borne diseases. We aimed to create and test the applicability of a rapid diagnostic system for West Nile virus that can be used under field conditions. METHODS: In this pilot study, various types of adult mosquito traps were applied within the regular mosquito monitoring activity framework for mosquito control. Then, the captured specimens were used for the detection of West Nile virus RNA under field conditions with a portable qRT-PCR approach within 3-4 h. Then, positive samples were subjected to confirmatory RT-PCR or NGS sequencing in the laboratory to obtain genome information of the virus. We implemented phylogenetic analysis to characterize circulating strains. RESULTS: A total of 356 mosquito individuals representing 7 species were processed in 54 pools, each containing up to 20 individuals. These pools were tested for the presence of West Nile virus, and two pools tested positive, containing specimens from the Culex pipiens and Anopheles atroparvus mosquito species. As a result of subsequent sequencing, we present the complete genome of West Nile virus and Bagaza virus. CONCLUSIONS: The rapid identification of infected mosquitoes is the most important component of quick response adulticide or larvicide treatments to prevent human cases. The conceptual framework of real-time surveillance can be optimized for other pathogens and situations not only in relation to West Nile virus. We present an early warning system for mosquito-borne diseases and demonstrate its application to aid rapid-response mosquito control actions.


Assuntos
Culex , Culicidae , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Vírus do Nilo Ocidental/genética , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/prevenção & controle , Febre do Nilo Ocidental/epidemiologia , Filogenia , Projetos Piloto , Controle de Mosquitos , Mosquitos Vetores
9.
Proc Biol Sci ; 291(2018): 20232432, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38471554

RESUMO

Mathematical models within the Ross-Macdonald framework increasingly play a role in our understanding of vector-borne disease dynamics and as tools for assessing scenarios to respond to emerging threats. These threats are typically characterized by a high degree of heterogeneity, introducing a range of possible complexities in models and challenges to maintain the link with empirical evidence. We systematically identified and analysed a total of 77 published papers presenting compartmental West Nile virus (WNV) models that use parameter values derived from empirical studies. Using a set of 15 criteria, we measured the dissimilarity compared with the Ross-Macdonald framework. We also retrieved the purpose and type of models and traced the empirical sources of their parameters. Our review highlights the increasing refinements in WNV models. Models for prediction included the highest number of refinements. We found uneven distributions of refinements and of evidence for parameter values. We identified several challenges in parametrizing such increasingly complex models. For parameters common to most models, we also synthesize the empirical evidence for their values and ranges. The study highlights the potential to improve the quality of WNV models and their applicability for policy by establishing closer collaboration between mathematical modelling and empirical work.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Humanos , Modelos Teóricos , Febre do Nilo Ocidental/transmissão
10.
J Infect Public Health ; 17(5): 868-880, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38555655

RESUMO

BACKGROUND: West Nile virus (WNV) is a mosquito-borne flavivirus. In humans, 80% of infections are asymptomatic, while approximately 20% experience influenza-like symptoms. Fewer than 1% develop the neuroinvasive form which can lead to encephalitis, meningitis, acute flaccid paralysis, and even death. The global spread of the virus to areas where it was not previously present has become a growing concern. Since the 2000 s, there have been numerous outbreaks affecting local and travelling populations worldwide. Given the lack of a vaccine, preventative measures are primarily focused on surveillance, vector control, and the use of personal protective behaviours (PPBs). The importance of PPBs is central to public health recommendations. However, translating these messages into coherent action by the public can prove challenging, as the uptake of such measures is inevitably influenced by socio-economic factors, awareness, knowledge, and risk perception. METHODS: A PRISMA-based systematic research was conducted on EMBASE, PubMed/MEDLINE, and Web of Science databases. PROSPERO registration number CRD42023459714. Quality of studies included in the final stage was evaluated using the Critical Appraisal Checklist for Cross-Sectional Study (CEBMa). RESULTS: 2963 articles were screened, and 17 studies were included in the final round. Out of these, six were deemed of high quality, ten were of medium quality, and one was of low quality. In almost all studies considered, both awareness and knowledge of WNV transmission were above 90%, while concern about WNV ranged from 50% to 80%. Concern about the safety of repellents, either with or without DEET, ranged from 27% to 70%. The percentage of people actually using repellents ranged from 30% to 75%, with the lowest usage reported among individuals over 60 years old (29%) and pregnant women (33%), and the highest among students aged 9-11 (75%). Concern for West Nile Virus (WNV) was consistently linked to an increase in taking preventative measures, including the use of repellents, by two to four times across studies. The school-based intervention was effective in increasing the practice of removing standing water (AOR=4.6; 2.7-8.0) and wearing long clothing (AOR=2.4; 95%CI: 1.3-4.3), but did not have a significant impact on the use of repellents. CONCLUSIONS: The present systematic review provides an overview of the knowledge, attitudes, and practices (KAP) of WNV and their determinants. While concern about West Nile Virus (WNV) and its effects can be a significant motivator, it is important to promote evidence-based personal protective behaviours (PPBs) to counter unwarranted fears. For example, the use of repellents among the most vulnerable age groups. Given the geographical expansion of WNV, it is necessary to target the entire population preventively, including those who are difficult to reach and areas not yet endemic. The findings of this investigation could have significant implications for public health and support well-informed and effective communication strategies and interventions.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Feminino , Gravidez , Pessoa de Meia-Idade , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/prevenção & controle , Febre do Nilo Ocidental/diagnóstico , Conhecimentos, Atitudes e Prática em Saúde , Estudos Transversais , Mosquitos Vetores
11.
Vet Res ; 55(1): 32, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493182

RESUMO

Outbreaks of West Nile virus (WNV) occur periodically, affecting both human and equine populations. There are no vaccines for humans, and those commercialised for horses do not have sufficient coverage. Specific antiviral treatments do not exist. Many drug discovery studies have been conducted, but since rodent or primate cell lines are normally used, results cannot always be transposed to horses. There is thus a need to develop relevant equine cellular models. Here, we used induced pluripotent stem cells to develop a new in vitro model of WNV-infected equine brain cells suitable for microplate assay, and assessed the cytotoxicity and antiviral activity of forty-one chemical compounds. We found that one nucleoside analog, 2'C-methylcytidine, blocked WNV infection in equine brain cells, whereas other compounds were either toxic or ineffective, despite some displaying anti-viral activity in human cell lines. We also revealed an unexpected proviral effect of statins in WNV-infected equine brain cells. Our results thus identify a potential lead for future drug development and underscore the importance of using a tissue- and species-relevant cellular model for assessing the activity of antiviral compounds.


Assuntos
Doenças dos Cavalos , Células-Tronco Pluripotentes Induzidas , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Cavalos , Humanos , Febre do Nilo Ocidental/veterinária , Febre do Nilo Ocidental/epidemiologia , Encéfalo , Antivirais/farmacologia , Antivirais/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico
12.
G Ital Nefrol ; 41(1)2024 Feb 28.
Artigo em Italiano | MEDLINE | ID: mdl-38426678

RESUMO

The West Nile Virus (WNV), an RNA arbovirus, has been transmitted by wild birds and conveyed by ticks and mosquitoes, with wide diffusion all over the world; it is not transmitted from human to human. It can give clinical symptoms only in a minority of infected subjects such as fever, headache, muscle tiredness, visual disturbances, drowsiness, convulsions and muscle paralysis; in the most serious cases even potentially fatal encephalitis. In the literature there are few reports on WNV infection in patients with kidney diseases: here we report our experience on two patients on peritoneal dialysis infected by WNV with a revision of the literature.


Assuntos
Culicidae , Nefropatias , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética , Aves
13.
Viruses ; 16(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38543749

RESUMO

BACKGROUND: West Nile virus (WNV) infection is a seasonal arbovirosis with the potential to cause severe neurological disease. Outcomes of the infection from WNV depend on viral factors (e.g., lineage) and host-intrinsic factors (e.g., age, sex, immunocompromising conditions). Immunity is essential to control the infection but may also prove detrimental to the host. Indeed, the persistence of high levels of pro-inflammatory cytokines and chemokines is associated with the development of blood-brain barrier (BBB) damage. Due to the importance of the inflammatory processes in the development of West Nile neuroinvasive disease (WNND), we reviewed the available literature on the subject. METHODS: According to the 2020 updated PRISMA guidelines, all peer-reviewed articles regarding the inflammatory response associated with WNND were included. RESULTS: One hundred and thirty-six articles were included in the data analysis and sorted into three groups (in vitro on-cell cultures, in vivo in animals, and in humans). The main cytokines found to be increased during WNND were IL-6 and TNF-α. We highlighted the generally small quantity and heterogeneity of information about the inflammatory patterns associated with WNND. CONCLUSIONS: Further studies are needed to understand the pathogenesis of WNND and to investigate the extent and the way the host inflammatory response either helps in controlling the infection or in worsening the outcomes. This might prove useful both for the development of target therapies and for the development of molecular markers allowing early identification of patients displaying an inflammatory response that puts them at a higher risk of developing neuroinvasive disease and who might thus benefit from early antiviral therapies.


Assuntos
Doenças do Sistema Nervoso , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Citocinas , Fator de Necrose Tumoral alfa
16.
Res Vet Sci ; 170: 105183, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359648

RESUMO

The role of wildlife in maintaining infectious diseases in veterinary medicine is often neglected, although the disease eradication process in domestic animals is continuously affected by the risk of pathogens transmission from wildlife as a primary source. The main aim of this paper was to estimate the prevalence and distribution of selected infectious diseases in wild ruminants in Serbia. In total, 259 sera from wild ruminants were tested for specific antibodies to bluetongue virus, Schmallenberg virus, Bovine viral diarrhea/border disease virus, Capripox virus, West Nile fever virus, Bovine herpes virus-1, Coxiella burnetii, Brucella spp., and Leptospira spp. Specific Capripox virus and Leptospira spp. antibodies were not detected in any of the 259 wild ruminant samples. Although one animal was detected positive for BVDV/BDV specific antibodies, with 99.8% confidence, the prevalence of BVD within this population could be very low i.e. essentially free from BVD infection. One and three positive animals were detected for Brucella spp. and Coxiella burnetii antibodies, respectively. Bovine herpes virus-1 specific antibodies were detected in 20.85% of the samples. The estimated seroprevalence of vector-borne diseases was 20.5% for Schmallenberg disease, 34.3% for West Nile fever, and 38.6% for Bluetongue. Considering the reported results, wildlife health status is a result of different factors in complex relation, such as the presence of disease in domestic animals, disease nature, pathogen characteristics, environmental factors, presence, and vector competence. Wildlife should be considered not only as a risk but as a source of important information on disease distribution and its indicators.


Assuntos
Doenças Transmissíveis , Febre do Nilo Ocidental , Animais , Sérvia/epidemiologia , Estudos Soroepidemiológicos , Estudos Transversais , Febre do Nilo Ocidental/veterinária , Ruminantes , Animais Selvagens , Animais Domésticos , Doenças Transmissíveis/veterinária , Anticorpos Antivirais
19.
Immunol Cell Biol ; 102(4): 280-291, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421112

RESUMO

Natural killer (NK) cells are cytotoxic lymphocytes important for viral defense. West Nile virus (WNV) infection of the central nervous system (CNS) causes marked recruitment of bone marrow (BM)-derived monocytes, T cells and NK cells, resulting in severe neuroinflammation and brain damage. Despite substantial numbers of NK cells in the CNS, their function and phenotype remain largely unexplored. Here, we demonstrate that NK cells mature from the BM to the brain, upregulate inhibitory receptors and show reduced cytokine production and degranulation, likely due to the increased expression of the inhibitory NK cell molecule, MHC-I. Intriguingly, this correlated with a reduction in metabolism associated with cytotoxicity in brain-infiltrating NK cells. Importantly, the degranulation and killing capability were restored in NK cells isolated from WNV-infected tissue, suggesting that WNV-induced NK cell inhibition occurs in the CNS. Overall, this work identifies a potential link between MHC-I inhibition of NK cells and metabolic reduction of their cytotoxicity during infection.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Humanos , Vírus do Nilo Ocidental/genética , Febre do Nilo Ocidental/genética , Encéfalo , Células Matadoras Naturais , Linfócitos T
20.
J Am Mosq Control Assoc ; 40(1): 1-10, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38314881

RESUMO

While most research on West Nile virus (WNV) and its main vector, the Culex mosquito, has been conducted in laboratory or urban settings, studies with field-caught mosquitoes in rural areas, such as west-central Illinois, are lacking. The objective of this research was to investigate key abiotic factors using macroclimate data, including temperature, precipitation, and wind speed, to determine their influence on field-caught mosquito abundance in 4 rural counties in Illinois from 2014 to 2016. Additionally, the relationship between minimum infection rate (MIR) and thermal time was examined. Using gravid traps at 15 sites, Culex mosquitoes were collected twice a week. A total of 5,255 adult female Culex mosquitoes (Cx. pipiens, Cx. quinquefasciatus, and Cx. restuans) were collected in 2014; 9,138 in 2015; and 5,702 in 2016. Regression models were developed based on outcomes of relationships between field-caught mosquitoes and abiotic factors. Precipitation and thermal time had the most significant relationship with mosquito abundance (r2 = 0.993 and r2 = 0.993, respectively), while wind speed was less (r2 = 0.714). The greatest number of Culex and the highest annual MIR were observed in 2015, which was also the driest of the 3 sampling seasons. Mosquito abundance was observed to increase with warmer degree days and MIR was found to increase with abundance in mosquitoes. These models can be used for other mosquito surveillance and monitoring studies in various climate types and environments.


Assuntos
Culex , Culicidae , Febre do Nilo Ocidental , Animais , Feminino , Febre do Nilo Ocidental/epidemiologia , Temperatura , Vento , Mosquitos Vetores , Illinois/epidemiologia
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