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1.
Cureus ; 16(6): e62486, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39015861

RESUMO

The West Nile virus (WNV) is the leading cause of mosquito-borne disease in the United States. Bell's palsy (BP) is a clinical syndrome associated with viral infections, but an association with West Nile virus (WNV) is not well-described, with only two cases reported in the literature. We present a case of a 68-year-old woman presenting with fevers and encephalopathy. Cerebrospinal fluid was positive for WNV. Following improvement, she developed facial weakness and was diagnosed with BP secondary to the WNV infection. Identifying BP associated with WNV infection may have significant clinical implications, but further studies are needed to fully characterize a causative relationship.

2.
Euro Surveill ; 29(30)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39056196

RESUMO

This report describes an unusual surge of West Nile fever in Israel in June 2024, during which 125 cases were diagnosed, compared with 4 cases on average during June in previous years (2014-23). Of the cases, 64 (62.1%) had neuroinvasive disease and 12 (9.6%) died; the 2024 case fatality rate was not significantly elevated vs the average rate in 2014-23. The early rise could be related to a temperature increase in spring and early summer of 2024.


Assuntos
Estações do Ano , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Israel/epidemiologia , Humanos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/mortalidade , Vírus do Nilo Ocidental/isolamento & purificação , Masculino , Feminino , Surtos de Doenças , Pessoa de Meia-Idade , Adulto , Incidência , Idoso , Vigilância da População
3.
Ther Adv Infect Dis ; 11: 20499361241247470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38693969

RESUMO

Powassan virus (POWV), a tick-borne flavivirus transmitted primarily by Ixodes ticks, poses a significant threat as it can lead to severe neuroinvasive illness. This review delves into the nuanced clinical presentation of Powassan infection, a challenge in diagnosis exacerbated by the absence of an available vaccine. Over the past decade, the prevalence of POWV has surged in North America, necessitating a thorough examination of its neurological manifestations alongside tick-borne encephalitis virus (TBEV). A comprehensive literature search conducted up to January 2024 revealed 135 cases of neurological symptoms associated with either Powassan or TBEV infection. Notably, severe occipital headache emerged as the most prevalent symptom (22.75%), followed by meningoencephalitis (10.34%), seizures (8.27%), and flaccid paresis (6.8%). Additional manifestations included poor balance, wide gait, dysarthria, facial nerve palsy, seizure, slurred speech, and absent deep tendon reflexes. Tragically, nine cases resulted in fatal outcomes attributed to POWV infection. This analysis highlights the intricate spectrum of neurological symptoms associated with Powassan infection and underscores the necessity for heightened awareness among medical practitioners, particularly in regions with a higher prevalence of the virus. The complexity of symptoms emphasizes the need for further research to unravel the factors contributing to this diversity. Additionally, exploring potential treatment avenues and vaccine development is crucial in addressing the rising threat posed by POWV, ultimately enhancing our ability to manage and prevent severe neurological outcomes.

4.
Pathogens ; 13(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38787234

RESUMO

West Nile virus (WNV) neuroinvasive disease (WNND) occurs in approximately 1 percent of WNV-infected patients and typically presents as encephalitis, meningitis, or acute flaccid paralysis (AFP). WNND remains a difficult inpatient diagnosis, creating significant challenges for prognostication and therapy selection. We characterized the clinical and diagnostic features of WNND cases at two major academic medical centers in New York City in routine clinical practice. We retrospectively reviewed the charts of thirty-six patients with WNND, including twenty-six encephalitis, four meningitis, and six AFP cases. The most common presenting symptoms were fever (86.1%) and gastrointestinal symptoms (38.9%) in addition to altered mental status (72.2%), lethargy (63.9%), gait disturbances (46.2%), and headache (44.4%). Fourteen (48.3%) patients displayed acute magnetic resonance imaging (MRI) findings, particularly T2 hyperintensities in the bilateral thalami, brainstem, and deep white matter. New York State Department of Health WNV CSF IgM testing was utilized for diagnosis in 58.3% of patients; however, just 38.1% had the result by discharge, compared to 85.6% of those who underwent serum IgM testing. The median length of stay was 13.5 days, 38.9% were intubated, and three patients (8.9%) died during acute hospitalization. Our findings underscore the morbidity, mortality, and diagnostic challenges of WNND, suggesting the potential utility of serum IgM testing in combination with confirmatory CSF testing to expedite diagnosis in the acute setting.

5.
Microorganisms ; 12(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38674602

RESUMO

Tick-borne encephalitis virus (TBEV) and West Nile virus (WNV) are the most important neuroinvasive arboviruses detected in Europe. In this study, we analyzed cerebrospinal fluid (CSF) concentrations of 12 proinflammatory chemokines (CCL2, CCL3, CCL4, CCL11, CCL17, CCL20, CXCL1, CXCL5, CXCL8, CXCL9, CXCL10, and CXCL11) in 77 patients with neuroinvasive diseases (NIDs). Flavivirus infection was confirmed in 62 patients (TBEV and WNV in 31 patients each), while in 15 patients the etiology of NID was not determined (NDE). Similar patterns of high-level expression of chemokines regulating monocyte/macrophage responses (CCL2), neutrophil recruitment (CXCL1 and CXCL8), and interferon-inducible chemoattractants for leukocytes (CXCL10 and CXCL11) have been observed in WNV and TBEV groups. None of the tested chemokines significantly differed between patients with TBEV or WNV. Concentrations of CCL17, CCL20, CXCL5, CXCL10, and CXCL11 were significantly lower in both WNV and TBEV groups compared to NID NDE patients. The logistic regression model showed that CSF concentrations of CXCL11, CXCL5, and CXCL10 could potentially be used for the classification of patients into the WNV or TBEV group versus groups with other NIDs. This study identified, for the first time, similar patterns of CSF chemokine expression in WNV and TBEV infections, suggesting common immunopathogenic mechanisms in neuroinvasive flavivirus infections that should be further evaluated.

6.
Open Forum Infect Dis ; 11(5): ofae188, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38680608

RESUMO

Background: In 2021, the state of Arizona experienced the largest focal outbreak of West Nile virus (WNV) in US history. Timely and accurate diagnostic testing remains a challenge for WNV due to transient viremia and limited immunoassay specificity. Recent studies have identified whole blood (WB) and urine as more sensitive specimen types for the detection of WNV RNA. Methods: We evaluated ordering practices, test performance, and patient characteristics of probable and confirmed cases. In total, we identified 190 probable and proven cases, including 127 patients (66.8%) with neuroinvasive disease. Results: Among all cases, only 29.5% had WNV polymerase chain reaction (PCR) testing ordered on WB, of which 80.3% resulted as positive, including 7 cases in which WNV serologic testing was negative and 5 cases for which serologic testing was not ordered. In comparison, only 23.7% of cases that had cerebrospinal fluid (CSF) PCR ordered had a positive result, including 3 cases that were negative by PCR on WB. In contrast, WNV PCR on WB detected 12 neuroinvasive cases that were CSF PCR negative. WNV PCR testing in urine was only ordered on 2 patients, both of whom were positive. Crossing cycle threshold (Ct) values were not significantly different between WB and CSF specimen types, nor was there a correlation between Ct value and days from symptom onset at the time of sample collection; all specimen types and time points had Ct values, with 98% above 30. WB was positive by WNV PCR in several patients for >7 days (range, 7-25 days) after symptom onset, as was the CSF PCR. Conclusions: Taken together, these findings indicate that WNV PCR testing on WB may be the best initial test for timely diagnosis of WNV infection, irrespective of clinical manifestation; however, if negative in patients with suspected neuroinvasive disease, WNV PCR testing on CSF should be ordered.

7.
Cureus ; 16(3): e57063, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38681299

RESUMO

Multiple sclerosis (MS) has a global prevalence exceeding two million people and is a leading cause of non-traumatic physical disability. MS can be treated with ocrelizumab, an anti-CD20 monoclonal antibody. West Nile virus (WNV) is the most common cause of mosquito-borne viral encephalitis in North America. It can lead to neuroinvasive WNV disease (WNND) affecting the brain and peripheral nervous system, especially in immunocompromised patients, such as those being treated with ocrelizumab for MS. WNND is exceedingly rare and reported in less than 1% of cases of WNV. It has been established that inpatient rehabilitation improves functional outcomes in patients with MS and those with WNND. However, the inpatient rehabilitation outcomes in patients diagnosed with both WNND and MS have not been reported. In this study, we aimed to examine the rehabilitation outcomes of MS patients on ocrelizumab diagnosed with WNND. We performed a retrospective chart review of patients with MS treated with ocrelizumab, who were diagnosed with WNND and admitted to a single facility. Rehabilitation outcomes were assessed using functional independence measure (FIM) scores on admission and discharge. Three patients met the inclusion criteria; two in acute rehab, and one in the long-term acute care hospital (LTACH). Both patients admitted to acute inpatient rehabilitation showed an improvement in FIM scores from admission to discharge, one patient from 9 to 16 and the other from 14 to 54. However, the patient admitted to the LTACH had no improvement in FIM score from admission to discharge. Patients admitted to acute rehab were ultimately discharged home, while the patient admitted to the LTACH required discharge to a subacute rehabilitation facility. Based on our findings, intense and prolonged comprehensive inpatient rehabilitation is associated with improved functional outcomes and increased likelihood of discharge to home in this population suffering from both central and peripheral nervous system involvement due to MS and WNND.

8.
Cureus ; 16(2): e53705, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38455772

RESUMO

Here we report a rare case with concurrent longitudinal extensive transverse myelitis (LETM) and leptomeningitis due to West Nile virus infection. A 47-year-old man initially presented with a six-day progressive, intermittent low-grade fever, headache, diplopia, malaise, myalgia, lower back pain, and difficulty walking that developed into progressive asymmetric paralysis. Initial lab work was notable for mild lactic acidosis and hyperCKemia. Brain MRI with contrast demonstrated small foci of leptomeningeal enhancement in the cerebellum, pons, medulla, and right CN VI at the cisternal segment. MRI of the spine was remarkable for edema in the spinal cord extending from T10 to L1 with diffuse enlargement of the cord contour at T11 to L1 and subtle enhancement of nerve roots within the thecal sac and cauda equina regions. The patient responded partially to five-day intravenous immunoglobulin therapy (total dose, 2 g/kg). Electromyography four months after the onset of symptoms also showed chronic reinnervation with active denervating features in thoracolumbar myotomes. Clinically, this case highlights the ill-defined and non-specific nature of the presentation of West Nile neuroinvasive disease. It can pose a diagnostic challenge for clinicians and, if unrecognized, is associated with significant morbidity and mortality in older and compromised individuals.

9.
Open Forum Infect Dis ; 11(3): ofae048, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38434615

RESUMO

Background: Bacillus cereus is a ubiquitous gram-positive rod-shaped bacterium that can cause sepsis and neuroinvasive disease in patients with acute leukemia or neutropenia. Methods: A single-center retrospective review was conducted to evaluate patients with acute leukemia, positive blood or cerebrospinal fluid test results for B cereus, and abnormal neuroradiographic findings between January 2018 and October 2022. Infection control practices were observed, environmental samples obtained, a dietary case-control study completed, and whole genome sequencing performed on environmental and clinical Bacillus isolates. Results: Five patients with B cereus neuroinvasive disease were identified. All patients had acute myeloid leukemia (AML), were receiving induction chemotherapy, and were neutropenic. Neurologic involvement included subarachnoid or intraparenchymal hemorrhage or brain abscess. All patients were treated with ciprofloxacin and survived with limited or no neurologic sequelae. B cereus was identified in 7 of 61 environmental samples and 1 of 19 dietary protein samples-these were unrelated to clinical isolates via sequencing. No point source was identified. Ciprofloxacin was added to the empiric antimicrobial regimen for patients with AML and prolonged or recurrent neutropenic fevers; no new cases were identified in the ensuing year. Conclusions: B cereus is ubiquitous in the hospital environment, at times leading to clusters with unrelated isolates. Fastidious infection control practices addressing a range of possible exposures are warranted, but their efficacy is unknown and they may not be sufficient to prevent all infections. Thus, including B cereus coverage in empiric regimens for patients with AML and persistent neutropenic fever may limit the morbidity of this pathogen.

10.
Viruses ; 16(3)2024 02 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
11.
J Biol Chem ; 300(4): 107168, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490434

RESUMO

Lipids have been previously implicated in the lifecycle of neuroinvasive viruses. However, the role of lipids in programmed cell death and the relationship between programmed cell death and lipid droplets (LDs) in neuroinvasive virus infection remains unclear. Here, we found that the infection of neuroinvasive virus, such as rabies virus and encephalomyocarditis virus could enhance the LD formation in N2a cells, and decreasing LDs production by targeting diacylglycerol acyltransferase could suppress viral replication. The lipidomics analysis revealed that arachidonic acid (AA) was significantly increased after reducing LD formation by restricting diacylglycerol acyltransferase, and AA was further demonstrated to induce ferroptosis to inhibit neuroinvasive virus replication. Moreover, lipid peroxidation and viral replication inhibition could be significantly alleviated by a ferroptosis inhibitor, ferrostatin-1, indicating that AA affected neuroinvasive virus replication mainly through inducing ferroptosis. Furthermore, AA was demonstrated to activate the acyl-CoA synthetase long-chain family member 4-lysophosphatidylcholine acyltransferase 3-cytochrome P450 oxidoreductase axis to induce ferroptosis. Our findings highlight novel cross-talks among viral infection, LDs, and ferroptosis for the first time, providing a potential target for antiviral drug development.


Assuntos
Ácido Araquidônico , Ferroptose , Gotículas Lipídicas , Replicação Viral , Ferroptose/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , Animais , Replicação Viral/efeitos dos fármacos , Camundongos , Ácido Araquidônico/metabolismo , Ácido Araquidônico/farmacologia , Vírus da Encefalomiocardite/efeitos dos fármacos , Diacilglicerol O-Aciltransferase/metabolismo , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Peroxidação de Lipídeos/efeitos dos fármacos , Coenzima A Ligases/metabolismo , Linhagem Celular Tumoral , Humanos
12.
Neurol Sci ; 45(2): 719-726, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37606743

RESUMO

INTRODUCTION: We aimed to describe neurological manifestations and functional outcome at discharge in patients with West Nile neuroinvasive disease. METHODS: This retrospective study enrolled inpatients treated in the University Clinic for Infectious and Tropical Diseases in Belgrade, Serbia, from 1 June until 31 October 2022. Functional outcome at discharge was assessed using modified Rankin scale. RESULTS: Among the 135 analyzed patients, encephalitis, meningitis and acute flaccid paralysis (AFP) were present in 114 (84.6%), 20 (14.8%), and 21 (15.6%), respectively. Quadriparesis/quadriplegia and monoparesis were the most frequent forms of AFP, present in 9 (6.7%) and 6 (4.4%) patients, respectively. Fourty-five (33.3%) patients had cerebellitis, 80 (59.3%) had rhombencephalitis, and 5 (3.7%) exhibited Parkinsonism. Ataxia and wide-based gait were present in 79 (58.5%) patients each. Fifty-one (37.8%) patients had tremor (41 (30.3%) had postural and/or kinetic tremor, 10 (7.4%) had resting tremor). Glasgow coma score (GCS) ≤ 8 and respiratory failure requiring mechanical ventilation developed in 39 (28.9%), and 33 (24.4%) patients, respectively. Quadriparesis was a risk factor for prolonged ventilator support (29.5 ± 16.8 vs. 12.4 ± 8.7 days, p = 0.001). At discharge, one patient with monoparesis recovered full muscle strength, whereas 8 patients with AFP were functionally dependent. Twenty-nine (21.5%) patients died. All of the succumbed had encephalitis, and 7 had quadriparesis. Ataxia, tremor and cognitive deficit persisted in 18 (16.9%), 15 (14.2%), and 22 (16.3%) patients at discharge, respectively. Age, malignancy, coronary disease, quadriparesis, mechanical ventilation, GCS ≤ 8 and healthcare-associated infections were risk factors for death (p = 0.001; p = 0.019; p = 0.004; p = 0.001; p < 0.001; p < 0.001, and p < 0.001, respectively).


Assuntos
Viroses do Sistema Nervoso Central , Mielite , Doenças Neuromusculares , Febre do Nilo Ocidental , Humanos , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/epidemiologia , Estudos Retrospectivos , Tremor/complicações , Sérvia/epidemiologia , Estações do Ano , alfa-Fetoproteínas , Quadriplegia/epidemiologia , Quadriplegia/etiologia , Paresia , Ataxia/complicações
13.
Microorganisms ; 11(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37763999

RESUMO

BACKGROUND: Although the Bhanja bandavirus (BHAV) is widely distributed in some European countries, human infections are rarely reported. This study analyzed the prevalence of BHAV antibodies in patients with neuroinvasive diseases of unsolved etiology. METHODS: A total of 254 Croatian patients who developed neurological symptoms during the four consecutive arbovirus transmission seasons (April 2017-October 2021) were tested. Cerebrospinal fluid (CSF) and urine samples were tested using RT-qPCR. In addition, CSF and serum samples were tested using a virus neutralization test. RESULTS: BHAV RNA was not detected in any samples, while neutralizing (NT) antibodies were detected in serum samples of 53/20.8% of patients (95% CI = 16.0-26.3). In two patients, BHAV NT antibodies were detected in the CSF, indicating a recent infection. Both patients were inhabitants of rural areas in continental Croatia, and one reported a tick bite two weeks before symptoms onset. The seropositivity was high in all age groups (15.2-29.1%). The majority of seropositive patients (94.3%) resided at altitudes less than 200 m above sea level. The prevalence rates correlated positively with population density and negatively with certain climate parameters (temperature, number of hot/warm days). CONCLUSIONS: The presented results indicate that BHAV is distributed in Croatia. Further studies are needed to determine the clinical significance of this neglected arbovirus.

14.
J Neuroimmunol ; 383: 578179, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657130

RESUMO

The 2020-21 West Nile Virus (WNV) outbreak in Andalusia, Spain, was the largest reported in the country, with eight cases of West Nile Neuroinvasive Disease (WNND) diagnosed in a tertiary hospital. Diagnosis of WNND is based on detecting WNV RNA, viral isolation, or demonstrating a specific immune response against the virus, with additional tests used to support the diagnosis. Treatment remains supportive, with variable outcomes. The potential efficacy of plasma exchange (PLEX) in select cases raises the possibility of an autoimmune component secondary to infectious pathology of the central nervous system. The influence of climate change on the expansion of WNV into new regions is a significant concern. It is crucial for physicians practicing in high-risk areas to be knowledgeable about the disease for early prevention and effective control measures.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Humanos , Vírus do Nilo Ocidental/genética , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/diagnóstico , Espanha/epidemiologia , Sistema Nervoso Central/patologia , Surtos de Doenças
15.
Diagn Microbiol Infect Dis ; 107(1): 115920, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37390574

RESUMO

Short and low-level viremia and virorachia, antibody cross-reactivity, IgM persistence, and inaccessibility of neutralization test, make laboratory diagnosis of West Nile virus (WNV) infection difficult. Recent investigations imply that WNV is excreted in urine longer and at higher concentrations compared to blood. The detection of WNV nucleic acid in cerebrospinal fluid (CSF), serum, and urine samples collected from 41 patients with suspected WNV neuroinvasive disease, was done by real-time RT-PCR assay. CSF and serum samples were also serologically tested using anti-WNV IgM/IgG ELISA kits. WNV infection was confirmed in 46.3% of patients by positive WNV RNA results in serum and/or CSF samples. The WNV RNA testing of urine allowed confirmation of 31.7% more cases. No association between WNV RNA urine positivity and age, gender, or the day of sample collection was found. The urine qRT-PCR can be a valuable diagnostic test for confirmation of probable cases of WNV neuroinvasive disease.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Humanos , Vírus do Nilo Ocidental/genética , Febre do Nilo Ocidental/diagnóstico , Anticorpos Antivirais , Reação em Cadeia da Polimerase em Tempo Real , RNA Viral/genética , Imunoglobulina G , Imunoglobulina M
16.
Redox Biol ; 64: 102769, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37285742

RESUMO

Cholesterol-24-hydroxylase (CH24H or Cyp46a1) is a reticulum-associated membrane protein that plays an irreplaceable role in cholesterol metabolism in the brain and has been well-studied in several neuro-associated diseases in recent years. In the present study, we found that CH24H expression can be induced by several neuroinvasive viruses, including vesicular stomatitis virus (VSV), rabies virus (RABV), Semliki Forest virus (SFV) and murine hepatitis virus (MHV). The CH24H metabolite, 24-hydroxycholesterol (24HC), also shows competence in inhibiting the replication of multiple viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 24HC can increase the cholesterol concentration in multivesicular body (MVB)/late endosome (LE) by disrupting the interaction between OSBP and VAPA, resulting in viral particles being trapped in MVB/LE, ultimately compromising VSV and RABV entry into host cells. These findings provide the first evidence that brain cholesterol oxidation products may play a critical role in viral infection.


Assuntos
Internalização do Vírus , Animais , Camundongos , Colesterol/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Homeostase , SARS-CoV-2/metabolismo , Colesterol 24-Hidroxilase/metabolismo
17.
J Virol ; 97(7): e0071523, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37310228

RESUMO

Powassan virus (POWV) is an emerging tick-borne flavivirus that causes neuroinvasive diseases, including encephalitis, meningitis, and paralysis. Similar to other neuroinvasive flaviviruses, such as West Nile virus (WNV) and Japanese encephalitis virus (JEV), POWV disease presentation is heterogeneous, and the factors influencing disease outcome are not fully understood. We used Collaborative Cross (CC) mice to assess the impact of host genetic factors on POWV pathogenesis. We infected a panel of Oas1b-null CC lines with POWV and observed a range of susceptibility, indicating that host factors other than the well-characterized flavivirus restriction factor Oas1b modulate POWV pathogenesis in CC mice. Among the Oas1b-null CC lines, we identified multiple highly susceptible lines (0% survival), including CC071 and CC015, and two resistant lines, CC045 and CC057 (>75% survival). The susceptibility phenotypes generally were concordant among neuroinvasive flaviviruses, although we did identify one line, CC006, that was specifically resistant to JEV, suggesting that both pan-flavivirus and virus-specific mechanisms contribute to susceptibility phenotypes in CC mice. We found that POWV replication was restricted in bone marrow-derived macrophages from CC045 and CC057 mice, suggesting that resistance could result from cell-intrinsic restriction of viral replication. Although serum viral loads at 2 days postinfection were equivalent between resistant and susceptible CC lines, clearance of POWV from the serum was significantly enhanced in CC045 mice. Furthermore, CC045 mice had significantly lower viral loads in the brain at 7 days postinfection than did CC071 mice, suggesting that reduced central nervous system (CNS) infection contributes to the resistant phenotype of CC045 mice. IMPORTANCE Neuroinvasive flaviviruses, such as WNV, JEV, and POWV, are transmitted to humans by mosquitoes or ticks and can cause neurologic diseases, such as encephalitis, meningitis, and paralysis, and they can result in death or long-term sequelae. Although potentially severe, neuroinvasive disease is a rare outcome of flavivirus infection. The factors that determine whether someone develops severe disease after a flavivirus infection are not fully understood, but host genetic differences in polymorphic antiviral response genes likely contribute to the outcome of infection. We evaluated a panel of genetically diverse mice and identified lines with distinct outcomes following infection with POWV. We found that resistance to POWV pathogenesis corresponded to reduced viral replication in macrophages, more rapid clearance of virus in peripheral tissues, and reduced viral infection in the brain. These susceptible and resistant mouse lines will provide a system for investigating the pathogenic mechanisms of POWV and identifying polymorphic host genes that contribute to resistance.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Vírus da Encefalite Transmitidos por Carrapatos , Encefalite , Infecções por Flavivirus , Flavivirus , Vírus do Nilo Ocidental , Humanos , Camundongos , Animais , Flavivirus/genética , Camundongos de Cruzamento Colaborativo , Infecções por Flavivirus/genética , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Vírus da Encefalite Japonesa (Espécie)/genética , Suscetibilidade a Doenças , Paralisia , 2',5'-Oligoadenilato Sintetase/genética
18.
Cureus ; 15(4): e38137, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37252502

RESUMO

Infection with West Nile virus (WNV) is often characterized by a mild febrile illness, but it can progress to meningitis, encephalitis, flaccid paralysis, and respiratory failure. The neuro-ophthalmological manifestations of this disease are uncommonly discussed. This case describes a 49-year-old undomiciled male who developed WNV flaccid paralysis with ophthalmoplegia. His symptoms began with difficulty in walking and progressed over several days to flaccid paralysis and ophthalmoplegia. Cerebrospinal fluid was positive for WNV immunoglobulin M antibodies and electromyography demonstrated acute denervation in several muscle groups. This is an unusual case of neuro-invasive WNV presenting with flaccid paralysis and ophthalmoplegia.

19.
Cureus ; 15(4): e37168, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37168156

RESUMO

West Nile encephalitis is a rare complication of infection from the West Nile virus (WNv). Viral encephalitis can mimic manifestations of other neurologic diseases. The purpose of this article is to report a case of a 60-year-old female who developed bilateral upper extremity tremors with West Nile encephalitis. She presented to a hospital in Southern Louisiana with persistent high fevers and new onset confusion. She soon developed tremors which persisted throughout her hospitalization. Computerized tomography (CT) of the head revealed no abnormalities. Cerebral spinal fluid (CSF) was remarkable for WNv IgM, and supportive care was pursued. After nearly three weeks, she was transferred to a skilled nursing facility for further care. The presentation of movement disorder with confusion usually raises concern for injury to the brain or spinal cord or other neurologic illnesses. Despite the presentation of movement disorders or other neurologic manifestations, viral etiologies should remain high on the differential when the patient has additional symptoms, such as fever and elevated white blood cell (WBC) count, to limit inappropriate diagnostic testing and treatment.

20.
Pharmaceutics ; 15(5)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37242804

RESUMO

Coronavirus infections are neuroinvasive and can provoke injury to the central nervous system (CNS) and long-term illness consequences. They may be associated with inflammatory processes due to cellular oxidative stress and an imbalanced antioxidant system. The ability of phytochemicals with antioxidant and anti-inflammatory activities, such as Ginkgo biloba, to alleviate neurological complications and brain tissue damage has attracted strong ongoing interest in the neurotherapeutic management of long COVID. Ginkgo biloba leaf extract (EGb) contains several bioactive ingredients, e.g., bilobalide, quercetin, ginkgolides A-C, kaempferol, isorhamnetin, and luteolin. They have various pharmacological and medicinal effects, including memory and cognitive improvement. Ginkgo biloba, through its anti-apoptotic, antioxidant, and anti-inflammatory activities, impacts cognitive function and other illness conditions like those in long COVID. While preclinical research on the antioxidant therapies for neuroprotection has shown promising results, clinical translation remains slow due to several challenges (e.g., low drug bioavailability, limited half-life, instability, restricted delivery to target tissues, and poor antioxidant capacity). This review emphasizes the advantages of nanotherapies using nanoparticle drug delivery approaches to overcome these challenges. Various experimental techniques shed light on the molecular mechanisms underlying the oxidative stress response in the nervous system and help comprehend the pathophysiology of the neurological sequelae of SARS-CoV-2 infection. To develop novel therapeutic agents and drug delivery systems, several methods for mimicking oxidative stress conditions have been used (e.g., lipid peroxidation products, mitochondrial respiratory chain inhibitors, and models of ischemic brain damage). We hypothesize the beneficial effects of EGb in the neurotherapeutic management of long-term COVID-19 symptoms, evaluated using either in vitro cellular or in vivo animal models of oxidative stress.

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