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Viruses Jan 2024Japanese encephalitis virus (JEV) belongs to the family and is a representative mosquito-borne flavivirus responsible for acute encephalitis and meningitis in humans.... (Review)
Review
Japanese encephalitis virus (JEV) belongs to the family and is a representative mosquito-borne flavivirus responsible for acute encephalitis and meningitis in humans. Despite the availability of vaccines, JEV remains a major public health threat with the potential to spread globally. According to the World Health Organization (WHO), there are an estimated 69,000 cases of JE each year, and this figure is probably an underestimate. The majority of JE victims are children in endemic areas, and almost half of the surviving patients have motor or cognitive sequelae. Thus, the absence of a clinically approved drug for the treatment of JE defines an urgent medical need. Recently, several promising and potential drug candidates were reported through drug repurposing studies, high-throughput drug library screening, and de novo design. This review focuses on the historical aspects of JEV, the biology of JEV replication, targets for therapeutic strategies, a target product profile, and drug development initiatives.
Topics: Child; Animals; Humans; Encephalitis Virus, Japanese; Encephalitis, Japanese; Encephalitis, Viral; High-Throughput Screening Assays; Drug Development
PubMed: 38399978
DOI: 10.3390/v16020202 -
The Pediatric Infectious Disease Journal Apr 2024To investigate the incidence and etiology of neonatal meningitis and to assess the associated risk factors, complications and outcomes in a nationwide multicenter...
OBJECTIVE
To investigate the incidence and etiology of neonatal meningitis and to assess the associated risk factors, complications and outcomes in a nationwide multicenter retrospective descriptive study.
METHOD
Twenty-seven centers from 7 geographical regions participated in the study. Newborns with a positive cerebrospinal fluid culture and/or cerebrospinal fluid polymerase chain reaction were included in the study. Demographic characteristics, clinical, laboratory and neuroimaging findings and mortality characteristics were analyzed.
RESULTS
A total of 634 confirmed cases of neonatal meningitis were included in the final analysis. The incidence was 2.51 per 1000 intensive care unit hospitalizations and mortality was observed in 149 (23.5%). Gram-positive bacteria were the predominant pathogens (54.5%), with coagulase-negative Staphylococci accounting for 45.3% of the cases, followed by Gram-negative organisms (37.3%). Viral and fungal organisms were isolated in 3.2% and 1.7% of the infants, respectively. Gram-negative culture growth was more common in infants who died (51% vs. 34.6%; P < 0.001). In the multivariable model, the odds of mortality was higher in those with respiratory distress requiring invasive ventilatory support [odds ratio (OR): 10.3; 95% confidence interval (CI): 4.9-21.7; P < 0.01], hypotension requiring inotropes (OR: 4.4; 95% CI: 2.7-7.1; P < 0.001), low birth weight status (OR: 2.5; 95% CI: 1.4-4.6; P = 0.002), lack of exposure to antenatal steroids (OR: 2.4; 95% CI: 1.3-4.4; P = 0.005) and the presence of concomitant sepsis (OR: 1.9; 95% CI: 1.1-3.2; P = 0.017).
CONCLUSIONS
In this nationwide study, neonatal meningitis was found to be associated with high mortality. Coagulase-negative Staphylococci was the most common causative microorganism followed by Gram-negative bacteria. Severe clinical presentation with invasive mechanical ventilation and inotrope requirement, as well as concomitant sepsis, low birth weight status and lack of exposure to antenatal steroids, were found to be independent risk factors for mortality.
Topics: Pregnancy; Infant; Humans; Infant, Newborn; Female; Retrospective Studies; Coagulase; Meningitis; Staphylococcus; Sepsis; Infant, Newborn, Diseases; Risk Factors; Steroids
PubMed: 38134373
DOI: 10.1097/INF.0000000000004197 -
The Egyptian Journal of Immunology Jul 2023Meningitis is a critical public health problem demanding immediate diagnosis and effective treatment due to high mortality rates. Cerebrospinal Fluid (CSF) lactate...
Meningitis is a critical public health problem demanding immediate diagnosis and effective treatment due to high mortality rates. Cerebrospinal Fluid (CSF) lactate concentration is a promising test to distinguish bacterial from viral meningitis. This study aimed to assess the performance and usefulness of CSF lactate as a biomarker to differentiate between bacterial and viral meningitis, and to determine its optimal level to differentiate between them. This prospective study included 50 patients, presented to Abbassia Fever Hospital with clinical findings consistent with meningitis. Patients were divided into two groups: Group1 included 30 patients with bacterial meningitis. Group 2 included 20 patients with viral meningitis. CSF lactate and other conventional CSF parameters were recorded. For CSF culture, Streptococcus pneumoniae was identified in 53.3% of the bacterial meningitis group. The polymerase chain reaction (PCR) indicated that S. pneumoniae was present in 26/50 (52%) and 3/50 (6%) patients were PCR negative. Among bacterial meningitis patients, S. pneumoniae was the most pervasive organism 26/30 (86.7%). The mean CSF lactate level was 9.3 mmol/l ±5.0 (2.2-17.6). There was a statistically significant strong agreement (Kappa=0.957) between types of meningitis diagnosed by PCR, culture, and CSF lactate at cutoff level of 7.2 mmol/L. This cutoff value was the best to differentiate between bacterial and viral meningitis. The validity of CSF lactate as a differentiating tool showed sensitivity, specificity, positive predictive value, and negative predictive value of 93.3%, 100%, 100%, and 90.9%, respectively. In conclusion, CSF lactate could be a valuable, sensitive, specific, and rapid marker for identifying the most dangerous bacterial causes of CNS infection, especially S. pneumoniae. CSF lactate can be routinely used as an early biochemical warning marker and a useful point-of-care test. CSF lactate at cutoff level of >7.2 mmol/L can accurately detect S. pneumoniae, the most prevalent organism in Egypt.
Topics: Humans; Lactic Acid; Prospective Studies; Diagnosis, Differential; Meningitis, Viral; Meningitis, Bacterial; Biomarkers; Sensitivity and Specificity
PubMed: 37440535
DOI: No ID Found -
Enfermedades Infecciosas Y... Jan 2024Enterovirus (EV) infections are the most frequent infections in the neonatal period and in many cases lead to hospital admission of the newborn (NB). The aim of this... (Observational Study)
Observational Study
INTRODUCTION
Enterovirus (EV) infections are the most frequent infections in the neonatal period and in many cases lead to hospital admission of the newborn (NB). The aim of this study was to determine the incidence of EV in the etiology of neonatal meningitis and to define the clinical characteristics of newborns with EV meningitis.
MATERIAL AND METHOD
Retrospective observational cohort study. Including 91 NBs with meningitis and gestational age greater than 34 weeks gestational age (GA) attended in our center over a period of 16 years.
RESULTS
The percentage of NBs with EV meningitis was higher than that of NBs with bacterial meningitis (BM) and accounted for 78% (n=71). Half of the NBs with EV infection had a history of epidemic environment among their caregivers. Fever was present in 96% of cases as a clinical sign and, in general, sensory disturbances represented the main neurological alterations. Antibiotics (ATB) were given to 71.4% of patients with EV infection. Detection of EV in CSF samples showed a high sensitivity for the diagnosis of EV meningitis. The most frequently implicated EV types were echovirus 11, coxsackievirus B5, echovirus 18, 25 and 7.
CONCLUSIONS
The results of this series show that enterovirus infection is a common cause of neonatal meningitis. These data underline the importance of rapid EV testing of infants with suspected meningitis. This allows early diagnosis and reduces antibiotic treatment, hospitalization time and related costs.
Topics: Infant; Infant, Newborn; Humans; Retrospective Studies; Enterovirus; Enterovirus Infections; Meningitis, Viral; Hospitalization; Infant, Newborn, Diseases; Anti-Bacterial Agents
PubMed: 36624031
DOI: 10.1016/j.eimce.2022.12.012 -
PloS One 2023Meningoencephalitis in children poses a diagnostic challenge, as etiology remains unknown for most of patients. Viral metagenomics by shotgun sequencing represents a...
INTRODUCTION
Meningoencephalitis in children poses a diagnostic challenge, as etiology remains unknown for most of patients. Viral metagenomics by shotgun sequencing represents a powerful tool for investigating unknown viral infections related to these cases.
PATIENTS AND METHODS
In a two-year, reference-centre, retrospective study, we investigated the usefulness of viral metagenomics of cerebrospinal fluid (CSF) for the diagnosis of viral infectious meningoencephalitis in forty seven pediatric patients, forty of them previously tested negative with a routine neurologic panel of viral targets that included herpesvirus 1-3 and enterovirus. We enhanced the detection by targeting viral sequences by hybrid capture. Raw sequence data was analysed using three bioinformatics pipelines.
RESULTS
Out of forty remaining children with meningoencephalitis of unknown viral etiology, a significant detection of viral nucleic acid by shotgun sequencing was found in twenty one, which was confirmed in ten of them by specific PCR: seven human endogenous retrovirus K113 (HER K113), one parechovirus 3, one human herpesvirus 5 (HHV5); one enterovirus B (Echovirus 9). The remaining eleven CSF were not confirmed by PCR: three rotavirus, one human herpesvirus 7 (HHV7), one influenza A, one mastadenovirus C, one sindbis virus, one torque teno virus, one human immunodeficiency virus 1 (HIV-1), one human alphaherpesvirus 3 (HHV3), one human alphaherpesvirus 2 (HHV2).
CONCLUSIONS
Underutilization of currently available meningitis-encephalitis diagnostic techniques such as BioFire® FilmArray® is the main cause of undiagnosed cases of meningoencephalitis. However, in this study we detected uncommon viruses that should be considered, including virus, rotavirus, sindbis virus, influenza A virus and HHV7. No other viral sequences that could be readily linked to CNS inflammation were detected. Some findings may stem from reagent or sample contamination, as seen with papillomavirus; for others, the clinical relevance of the virus remains uncertain and should be substantiated by further studies, as is the case with endogenous retrovirus K113 virus. Online bioinformatics pipeline CZID represents a valuable tool for analysing shotgun sequencing data in cases of neurological conditions with unknown etiology. Altogether, this study highlights the potential of shotgun sequencing in identifying previously unknown viral neuropathogens and sheds light on the interpretation issues related to its application in clinical microbiology.
Topics: Humans; Child; Retrospective Studies; Meningoencephalitis; Viruses; Virus Diseases; Inflammation; Herpesvirus 3, Human; Metagenomics
PubMed: 38127927
DOI: 10.1371/journal.pone.0296036 -
Journal of Virology Jul 2023Powassan virus (POWV) is an emerging tick-borne flavivirus that causes neuroinvasive diseases, including encephalitis, meningitis, and paralysis. Similar to other...
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 -null CC lines with POWV and observed a range of susceptibility, indicating that host factors other than the well-characterized flavivirus restriction factor modulate POWV pathogenesis in CC mice. Among the -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. 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.
Topics: Humans; Mice; Animals; Flavivirus; Collaborative Cross Mice; Flavivirus Infections; West Nile virus; Encephalitis Viruses, Tick-Borne; Encephalitis Virus, Japanese; Encephalitis; Disease Susceptibility; Paralysis; 2',5'-Oligoadenylate Synthetase
PubMed: 37310228
DOI: 10.1128/jvi.00715-23 -
European Journal of Neurology Jan 2024Data on clinical features and outcomes of benign recurrent lymphocytic meningitis (BRLM) are limited.
BACKGROUND AND PURPOSE
Data on clinical features and outcomes of benign recurrent lymphocytic meningitis (BRLM) are limited.
METHODS
This was a nationwide population-based cohort study of all adults hospitalized for BRLM associated with herpes simplex virus type 2 (HSV-2) at the departments of infectious diseases in Denmark from 2015 to 2020. Patients with single-episode HSV-2 meningitis were included for comparison.
RESULTS
Forty-seven patients with BRLM (mean annual incidence 1.2/1,000,000 adults) and 118 with single-episode HSV-2 meningitis were included. The progression risk from HSV-2 meningitis to BRLM was 22% (95% confidence interval [CI] 15%-30%). The proportion of patients with the triad of headache, neck stiffness and photophobia/hyperacusis was similar between BRLM and single-episode HSV-2 meningitis (16/43 [37%] vs. 46/103 [45%]; p = 0.41), whilst the median cerebrospinal fluid leukocyte count was lower in BRLM (221 cells vs. 398 cells; p = 0.02). Unfavourable functional outcomes (Glasgow Outcome Scale score of 1-4) were less frequent in BRLM at all post-discharge follow-up visits. During the study period, 10 (21%) patients with BRLM were hospitalized for an additional recurrence (annual rate 6%, 95% CI 3%-12%). The hazard ratio for an additional recurrence was 3.93 (95% CI 1.02-15.3) for patients with three or more previous episodes of meningitis.
CONCLUSIONS
Clinical features of BRLM were similar to those of single-episode HSV-2 meningitis, whilst post-discharge outcomes were more favourable. Patients with three or more previous episodes of meningitis had higher risk of an additional recurrence.
Topics: Adult; Humans; Cohort Studies; Meningitis, Viral; Aftercare; Polymerase Chain Reaction; Recurrence; Patient Discharge; Meningitis, Aseptic; Herpesvirus 2, Human; Denmark
PubMed: 37797296
DOI: 10.1111/ene.16081 -
Emerging Microbes & Infections Dec 2023West Nile virus (WNV) is a neurotropic flavivirus transmitted by the bites of infected mosquitoes. Severe forms of West Nile disease (WND) can curse with meningitis,...
West Nile virus (WNV) is a neurotropic flavivirus transmitted by the bites of infected mosquitoes. Severe forms of West Nile disease (WND) can curse with meningitis, encephalitis or acute flaccid paralysis. A better understanding of the physiopathology associated with disease progression is mandatory to find biomarkers and effective therapies. In this scenario, blood derivatives (plasma and serum) constitute the more commonly used biofluids due to its ease of collection and high value for diagnostic purposes. Therefore, the potential impact of this virus in the circulating lipidome was addressed combining the analysis of samples from experimentally infected mice and naturally WND patients. Our results unveil dynamic alterations in the lipidome that define specific metabolic fingerprints of different infection stages. Concomitant with neuroinvasion in mice, the lipid landscape was dominated by a metabolic reprograming that resulted in significant elevations of circulating sphingolipids (ceramides, dihydroceramides, and dihydrosphingomyelins), phosphatidylethanolamines and triacylglycerols. Remarkably, patients suffering from WND also displayed an elevation of ceramides, dihydroceramides, lactosylceramides, and monoacylglycerols in their sera. The dysregulation of sphingolipid metabolism by WNV may provide new therapeutic opportunities and supports the potential of certain lipids as novel peripheral biomarkers of WND progression.
Topics: Animals; Mice; West Nile Fever; West Nile virus; Sphingolipids; Ceramides; Biomarkers
PubMed: 37377355
DOI: 10.1080/22221751.2023.2231556 -
Frontiers in Immunology 2024The host immune response determines the differential outcome of acute or chronic viral infections. The comprehensive comparison of lymphoid tissue immune cells at the...
INTRODUCTION
The host immune response determines the differential outcome of acute or chronic viral infections. The comprehensive comparison of lymphoid tissue immune cells at the single-cell level between acute and chronic viral infections is largely insufficient.
METHODS
To explore the landscape of immune responses to acute and chronic viral infections, single-cell RNA sequencing(scRNA-seq), scTCR-seq and scBCR-seq were utilized to evaluate the longitudinal dynamics and heterogeneity of lymph node CD45 immune cells in mouse models of acute (LCMV Armstrong) and chronic (LCMV clone 13) viral infections.
RESULTS
In contrast with acute viral infection, chronic viral infection distinctly induced more robust NK cells and plasma cells at the early stage (Day 4 post-infection) and acute stage (Day 8 post-infection), respectively. Moreover, chronic viral infection exerted decreased but aberrantly activated plasmacytoid dendritic cells (pDCs) at the acute phase. Simultaneously, there were significantly increased IgA plasma cells (MALT B cells) but differential usage of B-cell receptors in chronic infection. In terms of T-cell responses, Gzma-high effector-like CD8 T cells were significantly induced at the early stage in chronic infection, which showed temporally reversed gene expression throughout viral infection and the differential usage of the most dominant TCR clonotype. Chronic infection also induced more robust CD4 T cell responses, including follicular helper T cells (Tfh) and regulatory T cells (Treg). In addition, chronic infection compromised the TCR diversity in both CD8 and CD4 T cells.
DISCUSSION
In conclusion, gene expression and TCR/BCR immune repertoire profiling at the single-cell level in this study provide new insights into the dynamic and differential immune responses to acute and chronic viral infections.
Topics: Mice; Animals; CD8-Positive T-Lymphocytes; Lymphocytic Choriomeningitis; Lymphocytic choriomeningitis virus; Persistent Infection; Receptors, Antigen, T-Cell; Lymph Nodes; Sequence Analysis, RNA
PubMed: 38352870
DOI: 10.3389/fimmu.2024.1341985