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Simple Summary: In the Russian Federation, small ruminant lentiviruses (SRLVs) circulate, causing slow infections that often develop and progress without clinical signs. The detection of seropositive animals leads to economic restrictions, including the prohibition of livestock product sales and the sale of breeding animals. In the investigation of biological samples from a clinically asymptomatic goat from a private farm, serological and molecular genetic methods (ELISA, PCR) yielded a positive result for lentivirus and antibodies against it. Subsequently, the virus was isolated in cell culture, and its presence was confirmed using transmission electron microscopy. Phylogenetic analysis revealed that the virus belongs to subtype B1. Extensive monitoring studies in different regions of the Russian Federation would give a clearer picture on the distribution of SLRVs and their classification. This article presents the results of virological and genetic studies of an isolate of caprine arthritis encephalitis (CAE) virus from the republic of Mordovia, Russian Federation. The isolate was found during monitoring studies of goat blood samples for the viral genome, and the presence of antibodies to lentiviruses was detected. According to the recommendation of the OIE, the positive result of PCR was confirmed with nucleotide sequencing. It was found that the obtained nucleotide sequence is identical to the genome of small ruminant lentiviruses presented in the GenBank database. Phylogenetic analysis showed that the isolate "Mordovia-2018" was included in the same cluster with an isolate from the Tver region of the Russian Federation detected in 2008. The sequence of the fragment of the env-gene of the isolate from the republic of Mordovia is available in GenBank under the number MN186380.1. To isolate the virus, a fraction of peripheral blood monocyte cells from the animal's blood was added to a monolayer of lamb synovial membrane cell culture, and ten passages were carried out. The first manifestations of the cytopathic effect were observed after the third passage on the eighth day of cultivation in the form of single large cells of irregular shape with 5–7 nuclei. At the seventh passage, multiple syncytium with 7–12 nuclei were observed. At subsequent passage levels, the formation of syncytium containing more than 10–14 nuclei was observed. [ABSTRACT FROM AUTHOR]

The Venezuelan equine encephalitis virus (VEEV) nonstructural protein 2 (nsP2) cysteine protease (EC 3.4.22.B79) is essential for viral replication. High throughput in silico/in vitro screening using a focused set of known cysteine protease inhibitors identified two epoxysuccinyl prodrugs, E64d and CA074 methyl ester (CA074me) and a reversible oxindole inhibitor. Here, we determined the X-ray crystal structure of the CA074-inhibited nsP2 protease and compared it with our E64d-inhibited structure. We found that the two inhibitors occupy different locations in the protease. We designed hybrid inhibitors with improved potency. Virus yield reduction assays confirmed that the viral titer was reduced by >5 logs with CA074me. Cell-based assays showed reductions in viral replication for CHIKV, VEEV, and WEEV, and weaker inhibition of EEEV by the hybrid inhibitors. The most potent was NCGC00488909-01 which had an EC50 of 1.76 µM in VEEV-Trd-infected cells; the second most potent was NCGC00484087 with an EC50 = 7.90 µM. Other compounds from the NCATS libraries such as the H1 antihistamine oxatomide (>5-log reduction), emetine, amsacrine an intercalator (NCGC0015113), MLS003116111-01, NCGC00247785-13, and MLS00699295-01 were found to effectively reduce VEEV viral replication in plaque assays. Kinetic methods demonstrated time-dependent inhibition by the hybrid inhibitors of the protease with NCGC00488909-01 (Ki = 3 µM) and NCGC00484087 (Ki = 5 µM). Rates of inactivation by CA074 in the presence of 6 mM CaCl2, MnCl2, or MgCl2 were measured with varying concentrations of inhibitor, Mg2+ and Mn2+ slightly enhanced inhibitor binding (3 to 6-fold). CA074 inhibited not only the VEEV nsP2 protease but also that of CHIKV and WEEV. [ABSTRACT FROM AUTHOR]

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Venezuelan equine encephalitis virus (VEEV) is a disease typically confined to South and Central America, whereby human disease is characterised by a transient systemic infection and occasionally severe encephalitis, which is associated with lethality. Using an established mouse model of VEEV infection, the encephalitic aspects of the disease were analysed to identify biomarkers associated with inflammation. Sequential sampling of lethally challenged mice (infected subcutaneously) confirmed a rapid onset systemic infection with subsequent spread to the brain within 24 h of the challenge. Changes in inflammatory biomarkers (TNF-α, CCL-2, and CCL-5) and CD45+ cell counts were found to correlate strongly to pathology ( R > 0.9 ) and present previously unproven biomarkers for disease severity in the model, more so than viral titre. The greatest level of pathology was observed within the olfactory bulb and midbrain/thalamus. The virus was distributed throughout the brain/encephalon, often in areas not associated with pathology. The principal component analysis identified five principal factors across two independent experiments, with the first two describing almost half of the data: (1) confirmation of a systemic Th1-biased inflammatory response to VEEV infection, and (2) a clear correlation between specific inflammation of the brain and clinical signs of disease. Targeting strongly associated biomarkers of deleterious inflammation may ameliorate or even eliminate the encephalitic syndrome of this disease. [ABSTRACT FROM AUTHOR]

Background: Pseudorabies virus (PRV) was thought to only infect animals. Recent studies have shown that it can also infect human. Case presentation: We report a case of pseudorabies virus encephalitis and endophthalmitis, diagnosed 89 days after onset, confirmed with intraocular fluid metagenomic next generation sequencing (mNGS) after the result of two cerebrospinal fluid (CSF) mNGS tests were negative. Although treatment with intravenous acyclovir, foscarnet sodium, and methylprednisolone improved the symptoms of encephalitis, significant diagnostic delay resulted in permanent visual loss. Conclusions: This case suggests that pseudorabies virus (PRV) DNA in the intraocular fluid may have a higher positivity than that in the CSF. PRV may persist in the intraocular fluid for an extended period and may thus require extended antiviral therapy. Patients with severe encephalitis and PRV should be examined with the focus on pupil reactivity and light reflex. A fundus examination should be performed in patients with a central nervous system infection, specifically, those in a comatose state, to help reduce eye disability. [ABSTRACT FROM AUTHOR]

Key Clinical Message: This case underlined the importance of having high suspicion for lobar hemorrhage as a rare but deadly complication of herpes simplex virus encephalitis and shone light upon the added complexity it poses on management on an already deadly disease. Herpes simplex virus (HSV) encephalitis is the most common type of sporadic encephalitis that inflicts high rates of morbidity and mortality. Differentiating a progressing encephalitis syndrome from a lobar hemorrhage as a complication presents a challenge and requires great vigilance and insight on part of the treating physician. [ABSTRACT FROM AUTHOR]

Zoonotic pathogens that are vector-transmitted have and continue to contribute to several emerging infections globally. In recent years, spillover events of such zoonotic pathogens have increased in frequency as a result of direct contact with livestock, wildlife, and urbanization, forcing animals from their natural habitats. Equines serve as reservoir hosts for vector-transmitted zoonotic viruses that are also capable of infecting humans and causing disease. From a One Health perspective, equine viruses, therefore, pose major concerns for periodic outbreaks globally. Several equine viruses have spread out of their indigenous regions, such as West Nile virus (WNV) and equine encephalitis viruses (EEVs), making them of paramount concern to public health. Viruses have evolved many mechanisms to support the establishment of productive infection and to avoid host defense mechanisms, including promoting or decreasing inflammatory responses and regulating host machinery for protein synthesis. Viral interactions with the host enzymatic machinery, specifically kinases, can support the viral infectious process and downplay innate immune mechanisms, cumulatively leading to a more severe course of the disease. In this review, we will focus on how select equine viruses interact with host kinases to support viral multiplication. [ABSTRACT FROM AUTHOR]

Venezuelan and eastern equine encephalitis viruses (VEEV and EEEV, respectively) are mosquito-borne, neuroinvasive human pathogens for which no FDA-approved therapeutic exists. Besides the biothreat posed by these viruses when aerosolized, arthropod transmission presents serious health risks to humans, as demonstrated by the 2019 outbreak of EEE disease in the United States that resulted in 38 confirmed cases, 19 deaths, and neurological effects in survivors. Here, we describe the discovery of a 2-pyrrolidinoquinazolinone scaffold, efficiently synthesized in two to five steps, whose structural optimization resulted in profound antiviral activity. The lead quinazolinone, BDGR-49, potently reduced cellular VEEV and EEEV titers by >7 log at 1 μM and exhibited suitable intravenous and oral pharmacokinetic profiles in BALB/c mice to achieve excellent brain exposure. Outstanding in vivo efficacy was observed in several lethal, subcutaneous infection mouse models using an 8-day dosing regimen. Prophylactically administered BDGR-49 at 25 mg kg−1 per day fully protected against a 10× LD50 VEEV Trinidad donkey (TrD) challenge in BALB/c mice. Similarly, we observed 70% protection when 10× LD50 EEEV FL93-939–infected C57BL/6 mice were treated prophylactically with BDGR-49 at 50 mg kg−1 per day. Last, we observed 100% therapeutic efficacy when mice, challenged with 10× LD50 VEEV TrD, were dosed at 48 hours after infection with BDGR-49 at 25 mg kg−1 per day. Mouse brain viral titers at 96 hours after infection were reduced to values near the limit of detection. Collectively, these results underscore the substantial development potential of a well-tolerated, brain-penetrant lead compound that shows promise in preventing and treating encephalitic alphavirus disease. Antiviral advance: Venezuelan and eastern equine encephalitis viruses (VEEV and EEEV, respectively) are mosquito-borne alphaviruses that can cause severe neurological and systemic disease in humans and equids. There is no approved vaccine or therapeutic available to treat human alphavirus infections. Cao et al. now describe the identification and optimization of a quinazolinone, BDGR-49, that showed potent antiviral activity against VEEV and EEEV in vitro and outstanding prophylactic and therapeutic efficacy in mouse models of VEEV and EEEV. BDGR-49 also showed promising pharmacokinetic profiles and evidence of brain penetration. Together these findings highlight BDGR-49 as a promising compound for treating encephalitic alphavirus infection. —CF [ABSTRACT FROM AUTHOR]

We describe a 4-year-old male patient in Ohio, USA, who had encephalitis caused by Powassan virus lineage 2. Virus was detected by using metagenomic next-generation sequencing and confirmed with IgM and plaque reduction neutralization assays. Clinicians should recognize changing epidemiology of tickborne viruses to enhance encephalitis diagnosis and management. [ABSTRACT FROM AUTHOR]

Central nervous system virus infections are a major cause of morbidity and mortality worldwide and a significant global public health concern. As in many tissues, inflammation and immune responses in the brain, despite their protective roles, can also be harmful. Control of brain inflammation is important in many neurological diseases from encephalitis to multiple sclerosis and neurogenerative disease. The suppressors of cytokine signaling (SOCS) proteins are a key mechanism controlling inflammatory and immune responses across all tissues including the brain. Using a mouse model system, we demonstrate that lack of SOCS4 results in changes in the pathogenesis and clinical outcome of a neurotropic virus infection. Relative to wild‐type mice, SOCS4‐deficient mice showed accelerated clearance of virus from the brain, lower levels of persisting viral RNA in the brain, increased neuroinflammation and more severe neuropathology. We conclude that, in the mouse brain, SOCS4 is a vital regulator of antiviral immunity that mediates the critical balance between immunopathology and virus persistence. [ABSTRACT FROM AUTHOR]

Background & objectives: Sandflies are implicated as vectors of Chandipura virus (CHPV) (Vesiculovirus: Rhabdoviridae). The virus is prevalent in central India including Vidarbha region of Maharashtra. CHPV causes encephalitis in children below 15 yr of age with case fatality rates ranging from 56 to 78 per cent. The present study was undertaken to determine the sandfly fauna in the CHPV endemic Vidharba region. Methods: A year round survey of sandflies was conducted at 25 sites in three districts of Vidarbha region. Sandflies were collected from their resting sites using handheld aspirators and identified using taxonomical keys. Results: A total of 6568 sandflies were collected during the study. Approximately 99 per cent of the collection belonged to genus Sergentomyia, which was represented by Ser. babu, Ser. bailyi and Ser. punjabensis. Genus Phlebotomus was represented by Ph. argentipes and Ph. papatasi. Ser. babu was the predominant species (70.7%) collected during the study. Ph. argentipes was detected in four villages with 0.89 per cent, whereas Ph. papatasi was detected in only one village with 0.32 per cent of the total collection. CHPV could not be isolated despite processing all the sandflies for virus isolation in cell culture. Interpretation & conclusions: The present study showed influence of higher temperature and relative humidity on sandfly population dynamics. An important observation during the study was the absence or decline in the population of Ph. papatasi and Ph. argentipes in the study area. Surge in Sergentomyia population and their breeding/resting in close vicinity to humans pose a concern as they are known to harbour CHPV and other viruses of public health importance. [ABSTRACT FROM AUTHOR]

Viruses with encephalitogenic potential can cause neurological conditions of clinical and epidemiological importance, such as Saint Louis encephalitis virus, Venezuelan equine encephalitis virus, Eastern equine encephalitis virus, Western equine encephalitis virus, Dengue virus, Zika virus, Chikungunya virus, Mayaro virus and West Nile virus. The objective of the present study was to determine the number of arboviruses with neuroinvasive potential isolated in Brazil that corresponds to the collection of viral samples belonging to the Department of Arbovirology and Hemorrhagic Fevers, Evandro Chagas Institute (SAARB/IEC) of the Laboratory Network of National Reference for Arbovirus Diagnosis from 1954 to 2022. In the analyzed period, a total of 1,347 arbovirus samples with encephalitogenic potential were isolated from mice; 5,065 human samples were isolated exclusively by cell culture; and 676 viruses were isolated from mosquitoes. The emergence of new arboviruses may be responsible for diseases still unknown to humans, making the Amazon region a hotspot for infectious diseases due to its fauna and flora species characteristics. The detection of circulating arboviruses with the potential to cause neuroinvasive diseases is constant, which justifies the continuation of active epidemiological surveillance work that offers adequate support to the public health system regarding the virological diagnosis of circulating arboviruses in Brazil. [ABSTRACT FROM AUTHOR]

In May 2022, a re-emerging viral pathogen belonging to the Poxviridae was first reported from the UK, and WHO confirmed the outbreak after the prevalence of the disease increased. As of February 15, 2023, more than 85,000 confirmed cases have been recorded in 110 countries. Due to the spread of the virus across multiple countries, WHO declared the mpox outbreak as a public health emergency. Human mpox virus is an enveloped virus with a linear double-stranded DNA that can cause encephalitis with neurological complications such as pharyngitis, fever, anorexia, adenopathy, vesiculopapular rash, and headache. Dysregulation of microRNAs in viral encephalitis has been reported in a variety of documents. In this mini-review, we aim to discuss the possibility of CNS-related microRNA dysregulation in mpox-related encephalitis. [ABSTRACT FROM AUTHOR]

Vector-borne diseases spread from wild animals and their associated ectoparasites to humans and domesticated animals. Wildlife markets are recognized as important areas where this transfer can take place. We assessed the potential for spreading vector-borne diseases in two live and wet markets in Myanmar (Mong La, on the Myanmar-China border) and Indonesia (Sukahaji in Bandung on the island of Java) by making an inventory of all live and freshly killed wild mammals for sale. For eight mammal families, we quantified the number of animals on offer, and we used a heatmap cluster analysis to map vector-borne diseases that these families may carry. In Myanmar, we observed large numbers of wild pigs and deer (potentially carrying West Nile and various encephalitis viruses) whereas in Indonesia we observed Old World fruit bats (potentially carrying Chikungunya and encephalitis viruses) and squirrels (potentially carrying West Nile and encephalitis viruses). The trade in Indonesia was dominated by live mammals offered for sale as pets, and only Old World fruit bats and squirrels traded for traditional Asian medicine were killed in the markets. The trade in Myanmar was more geared towards wild meat (e.g., wild pigs, deer, primates) and traditional Asian medicine (squirrels). The combined risks of vector-borne diseases spreading from traded animals to human health highlight the need for an integrated approach protecting public health, economic interests and biodiversity. [ABSTRACT FROM AUTHOR]

Herpes simplex encephalitis (HSE) is the most common cause of infectious encephalitis. Our case is of a 75‐year‐old woman who presented with dysuria and altered mental status. Our case addresses the difficulties in diagnosis and highlights the importance of early recognition of HSE and its associated neurological sequelae. [ABSTRACT FROM AUTHOR]

Introduction: Eastern equine encephalitis virus (EEEV) and Venezuelan equine encephalitis virus (VEEV) viruses are zoonotic pathogens affecting humans, particularly equines. These neuroarboviruses compromise the central nervous system and can be fatal in different hosts. Both have significantly influenced Colombia; however, few studies analyse its behaviour, and none develop maps using geographic information systems to characterise it. Objective: To describe the temporal-spatial distribution of those viruses in Colombia between 2008 and 2019. Methods: Retrospective cross-sectional descriptive study, based on weekly reports by municipalities of the ICA, of the surveillance of both arboviruses in equines, in Colombia, from 2008 to 2019. The data were converted into databases in Microsoft Access 365®, and multiple epidemiological maps were generated with the Kosmo RC1®3.0 software coupled to shape files of all municipalities in the country. Results: In the study period, 96 cases of EEE and 70 of VEE were reported, with 58% of EEE cases occurring in 2016 and 20% of EEV cases in 2013. The most affected municipalities for EEE corresponded to the department of Casanare: Yopal (20), Aguazul (16), and Tauramena (10). In total, 40 municipalities in the country reported ≥1 case of EEE. Conclusions: The maps allow a quick appreciation of groups of neighbouring municipalities in different departments (1° political division) and regions of the country affected by those viruses, which helps consider the expansion of the disease associated with mobility and transport of equines between other municipalities, also including international borders, such as is the case with Venezuela. In that country, especially for EEV, municipalities in the department of Cesar are bordering and at risk for that arboviral infection. there is a high risk of equine encephalitis outbreaks, especially for VEE. This poses a risk also, for municipalities in the department of Cesar, bordering with Venezuela. [ABSTRACT FROM AUTHOR]

New World alphaviruses including Venezuelan Equine Encephalitis Virus (VEEV) and Eastern Equine Encephalitis Virus (EEEV) are mosquito-transmitted viruses that cause disease in humans and equines. There are currently no FDA-approved therapeutics or vaccines to treat or prevent exposure-associated encephalitic disease. The ubiquitin proteasome system (UPS)-associated signaling events are known to play an important role in the establishment of a productive infection for several acutely infectious viruses. The critical engagement of the UPS-associated signaling mechanisms by many viruses as host–pathogen interaction hubs led us to hypothesize that small molecule inhibitors that interfere with these signaling pathways will exert broad-spectrum inhibitory activity against alphaviruses. We queried eight inhibitors of the UPS signaling pathway for antiviral outcomes against VEEV. Three of the tested inhibitors, namely NSC697923 (NSC), bardoxolone methyl (BARM) and omaveloxolone (OMA) demonstrated broad-spectrum antiviral activity against VEEV and EEEV. Dose dependency and time of addition studies suggest that BARM and OMA exhibit intracellular and post-entry viral inhibition. Cumulatively, our studies indicate that inhibitors of the UPS-associated signaling pathways exert broad-spectrum antiviral outcomes in the context of VEEV and EEEV infection, supporting their translational application as therapeutic candidates to treat alphavirus infections. [ABSTRACT FROM AUTHOR]

Viral infections are a common cause of encephalitis. This study investigated the relationship between the incidence of encephalitis and that of respiratory and enteric viral infections in all age groups from 2015 to 2019, using the Health Insurance Review and Assessment (HIRA) Open Access Big Data Platform. We identified monthly incidence patterns and seasonal trends using the autoregressive integrated moving average (ARIMA). The Granger causality test was used to analyze correlations between encephalitis incidence and the positive detection rate (PDR) at 1-month intervals. A total of 42,775 patients were diagnosed with encephalitis during the study period. The incidence of encephalitis was highest in the winter (26.8%). The PDRs for respiratory syncytial virus (HRSV) and coronavirus (HCoV) were associated with the trend in encephalitis diagnosis in all age groups, with a 1-month lag period. In addition, an association with norovirus was observed in patients aged over 20 years, and with influenza virus (IFV) in patients aged over 60 years. This study found that HRSV, HCoV, IFV, and norovirus tended to precede encephalitis by 1 month. Further research is required to confirm the association between these viruses and encephalitis. [ABSTRACT FROM AUTHOR]

Alphavirus replication is dependent on host cell organelles to facilitate multiple steps of the viral life cycle. New world alphaviruses (NWA) consisting of eastern, western and Venezuelan equine encephalitis viruses are a subgroup of alphaviruses associated with central nervous system disease. Despite differing morbidity and mortality amongst these viruses, all are important human pathogens due to their transmission through viral aerosolization and mosquito transmission. In this review, we summarize the utilization of host organelles for NWA replication and the subversion of the host innate immune responses. The impact of viral proteins and replication processes on organelle function is also discussed. Literature involving old world alphaviruses (OWA), such as chikungunya virus and Sindbis virus, is included to compare and contrast between OWA and NWA and highlight gaps in knowledge for NWA. Finally, potential targets for therapeutics or vaccine candidates are highlighted with a focus on host-directed therapeutics. • Characterize the impact of new world alphaviruses on host immune response and cell function. • Compare and contrast new world and old world alphavirus cellular interactions. • Highlight areas for advancement and therapeutics for new world alphaviruses. [ABSTRACT FROM AUTHOR]

• Cerebral infections are a common cause of structural focal epilepsy worldwide. • Mesial temporal sclerosis from early-life infections is linked to favourable surgical outcomes. • Temporal resections are more effective than extratemporal resections. • Hemispheric procedures can have favourable outcomes in cases with severe damage. Cerebral infections are a common cause of structural focal epilepsy, particularly in developing countries, where the risk of unprovoked seizures is higher and is related to brain lesions and status epilepticus during the acute phase. Despite the prevalence of pharmacoresistant epilepsy after cerebral infections, few patients are referred for epilepsy surgery. However, those with mesial temporal sclerosis (MTS), particularly linked to meningitis or encephalitis in early life, are excellent surgical candidates. Encephalitis before age four is associated with MTS, indicating a period of hippocampal vulnerability. Temporal resections are the most common procedures in these patients. In contrast, extratemporal resections are less common and generally less successful, especially in patients with multifocal epilepsy or parasitic infections. Patients with severe hemispheric damage from infections and contralateral hemiparesis may undergo hemispheric procedures, with overall favorable outcomes. Surgery for post-viral encephalitis, such as herpes simplex virus encephalitis, is often less effective due to widespread brain involvement, though younger patients with unilateral hippocampal atrophy fare better. Although neurocysticercosis is a leading cause of epilepsy in endemic regions, surgery is rarely performed. However, resecting MTS along with calcified lesions can improve seizure control in pharmacoresistant cases. This review emphasizes the importance of surgery for appropriately selected patients with postinfectious epilepsy. [ABSTRACT FROM AUTHOR]

Flaviviruses transmitted by arthropods, including the Murray Valley Encephalitis Virus (MVEV), are RNA viruses capable of causing severe encephalitis in various hosts. The spread of these viruses is closely linked to climatic conditions and the habitats of host and vector species, leading to outbreaks in new geographic regions. Notable encephalitis-causing flaviviruses include Japanese encephalitis virus (JEV), West Nile virus (WNV), and Kunjin virus (KUNV). MVEV, primarily spread by the mosquito Culex annulirostris and amplified by water birds such as egrets and Nankeen night herons, has caused significant outbreaks in Australia, including severe epidemics in 1951, 1956, and 1974. Despite its severity, no rapid diagnostic techniques or effective antiviral treatments are available, and current interventions are limited to supportive care and mosquito management. Given the absence of a licensed vaccine, this study aimed to develop a multi-epitope hybrid vaccine targeting MVEV using in silico approaches. The study focused on identifying B-cell and T-cell epitopes from the MVEV Envelope (E) protein, constructing a vaccine candidate, and computationally validating its immunogenic potential. The designed vaccine underwent rigorous analysis of its antigenic properties, allergenicity, and toxicity. Disulfide engineering and assessment of physicochemical properties ensured the structural integrity of the vaccine, supported by Ramachandran plot and ProSA web analyses. Molecular docking studies assessed the vaccine's binding affinities with TLR-3, and MHC-I. Population coverage analysis of MHC-I and MHC-II epitopes evaluated global efficacy. Additionally, molecular dynamics simulations explored the stability of docked complexes, and PDBsum analysis elucidated interaction details. Immunological simulations were conducted to predict immune response outcomes, providing comprehensive validation of the vaccine's antigenicity. The findings highlight the potential of a multi-epitope vaccine as a viable strategy for MVEV prevention. • Murray Valley Encephalitis Virus (MVEV), spread by Culex annulirostris mosquitoes and water birds, causes severe encephalitis. • No licensed vaccine for MVEV exists; treatments are lacking, relying on supportive care and mosquito control measures. • This study designed a multi-epitope vaccine in silico , targeting B-cell and T-cell epitopes from the MVEV Envelope (E) protein. • Binding affinities with TLR-3 and MHC-I were assessed, and molecular dynamics simulations evaluated the stability of docked complexes. • Immunological simulations predicted a strong immune response, supporting the vaccine's potential as a viable option for global MVEV prevention. [ABSTRACT FROM AUTHOR]

To compare functional outcomes and help differentiate between important causative agents of acute infectious encephalitis in adults, focusing on West Nile virus encephalitis (WNVE). The electronic database of Tel Aviv Medical Center was screened for patients admitted during 2010–2020 with acute encephalitis. Additionally, patient laboratory results during the same period were screened for CSF samples positive for common pathogens causing encephalitis. The main patient groups were compared in terms of clinical characteristics and functional outcomes. One hundred and five infectious encephalitis patients were identified. WNVE patients (n = 31) and VZV encephalitis (VZVE) patients (n = 31) were older than HSV1 encephalitis (HSV1E) patients (n = 15) (median ages 73, 76, 51, respectively). WNVE patients had a more prominent inflammatory profile. CSF characteristics significantly differed between groups, with an extreme mononuclear white blood cell predominance in VZVE patients (median 98%). Functional outcomes at discharge were significantly worse in WNVE patients (median modified Rankin Scale score 4 at hospital discharge, 2.5 at last follow-up) when compared with HSV1E patients (2.5, 1, respectively) and VZVE patients (1.5, 1, respectively). In odds with previous reports, WNVE and VZVE in this study were far more prevalent than HSV1E. Differences in clinical characteristics could prove clinically useful early in encephalitis, including an association of WNVE with a relatively prominent inflammatory profile (somewhat resembling a bacterial infection) and an extreme mononuclear white blood cell predominance in VZVE. The detrimental outcome of WNVE emphasizes the need to advance research on WNV infection. • A cohort of 105 adult infectious encephalitis cases from a single medical center in Israel was retrospectively analyzed • WNV and VZV, not HSV1, were the commonest causes of adult infectious encephalitis • WNVE was associated with a worse outcome at discharge than HSV1E and VZVE • Some features may provide early clues in recognizing the infectious encephalitic agent WNV: West Nile virus. HSV1: herpes simplex 1 virus. VZV: varicella-zoster virus. WNVE: West Nile virus encephalitis. HSV1E: herpes simplex 1 virus encephalitis. VZVE: varicella-zoster virus encephalitis. [ABSTRACT FROM AUTHOR]

Inhibition of AP-2-associated protein kinase 1 (AAK1) has been shown to be a promising avenue for the development of broad-spectrum antiviral agents. On a previously described AAK1 inhibitor based on a pyrrolo[2,3- b ]pyridine scaffold, the concept of isosterism was applied, by replacing a carboxamide linker by various five-membered heterocycles. It led to the discovery of a novel series of AAK1 inhibitors with IC 50 values in the low nM range, that also displayed antiviral activity against the dengue virus and Venezuelan equine encephalitis virus. [Display omitted] • AAK1 inhibitors are promising broad-spectrum antiviral agents. • Various isosteres of known pyrrolo [2,3- b ]pyridines were prepared. • Compounds show potent AAK1 inhibition in the low nM range. • Selected analogues display antiviral activity against DENV-2 and VEEV. [ABSTRACT FROM AUTHOR]

Importance:Powassan virus is a rare but increasingly recognized cause of severe neurological disease. Objective:To highlight the diagnostic challenges and neuropathological findings in a fatal case of Powassan encephalitis caused by deer tick virus (lineage II) in a patient with follicular lymphoma receiving rituximab, with nonspecific anti-GAD65 antibodies, who was initially seen with fever and orchiepididymitis. Design, Setting, and Participants:Comparison of clinical, radiological, histological, and laboratory findings, including immunohistochemistry, real-time polymerase chain reaction, antibody detection, and unbiased sequencing assays, in a single case report (first seen in December 2016) at an academic medical center. Exposure:Infection with Powassan virus. Main Outcomes and Measures:Results of individual assays compared retrospectively. Results:In a 63-year-old man with fatal Powassan encephalitis, serum and cerebrospinal fluid IgM antibodies were not detected via standard methods, likely because of rituximab exposure. Neuropathological findings were extensive, including diffuse leptomeningeal and parenchymal lymphohistiocytic infiltration, microglial proliferation, marked neuronal loss, and white matter microinfarctions most severely involving the cerebellum, thalamus, and basal ganglia. Diagnosis was made after death by 3 independent methods, including demonstration of Powassan virus antigen in brain biopsy and autopsy tissue, detection of viral RNA in serum and cerebrospinal fluid by targeted real-time polymerase chain reaction, and detection of viral RNA in cerebrospinal fluid by unbiased sequencing. Extensive testing for other etiologies yielded negative results, including mumps virus owing to prodromal orchiepididymitis. Low-titer anti-GAD65 antibodies identified in serum, suggestive of limbic encephalitis, were not detected in cerebrospinal fluid. Conclusions and Relevance:Owing to the rarity of Powassan encephalitis, a high degree of suspicion is required to make the diagnosis, particularly in an immunocompromised patient, in whom antibody-based assays may be falsely negative. Unbiased sequencing assays have the potential to detect uncommon infectious agents and may prove useful in similar scenarios.

Yet post-viral encephalitis does not appear to be limited to HSE but also occurs following a wide range of other viral encephalitis variants, including Japanese B-encephalitis,[9] arguing against this idea. This scientific commentary refers to 'Neurologic complications in herpes simplex encephalitis: clinical, immunological and genetic studies' by Armangué I et al. i (https://doi.org/10.1093/brain/awad238). None had NMDAR or other neuronal antibodies at the time of the HSE, yet some (30%) went on to develop neuronal antibodies without clinical relapses. [Extracted from the article]

• A case of varicella-zoster virus encephalitis after adult ABO-incompatible living donor liver transplantation that was previously reported only in a pediatric case. • The patient had a convulsion attack and loss of consciousness on postoperative day 15. • A concomitant massive bleeding tendency was observed but controlled after the treatment of varicella-zoster virus encephalitis. There have never been any reports of adult varicella-zoster virus (VZV) encephalitis cases. Here, we report a case of VZV encephalitis after adult ABO-incompatible living donor liver transplantation (LDLT). A 38-year-old man with decompensated liver cirrhosis caused by the hepatitis C virus was referred to our hospital as an LDLT candidate. Rituximab was administered 3 weeks before the operation, and immunosuppression agents were administered 1 week before the LDLT. Plasma exchange was performed 3 times before the LDLT. The right lobe from his mother's liver was used for the ABO-incompatible LDLT. On postoperative day (POD) 9, vascular stenting for intraabdominal bleeding from the common hepatic artery was performed by interventional radiology and was followed by re-laparotomy for abdominal drainage of the hematoma. However, there were various degrees of continued bleeding thereafter. On POD 12, due to a convulsion seizure with loss of consciousness, the patient was started on anticonvulsant therapy. On POD 15, there was an increased frequency of convulsion attacks and a prolonged loss of consciousness. A lumbar puncture was performed on POD 20 due to the appearance of shingles. The positive polymerase chain reaction of the VZV-DNA from the cerebrospinal fluid was detected, and he was diagnosed with VZV encephalitis. He rapidly regained alertness, and there were no further observed convulsion attacks after administration of a steroid pulse and acyclovir. Brain magnetic resonance imaging performed on 2 subsequent postoperative months showed findings that matched with VZV encephalitis. He was discharged as he had recovered and was ambulatory 3 months after LDLT. [ABSTRACT FROM AUTHOR]

Key Clinical Message: When treating patients with EBV encephalitis, the possibility of XLP should be considered. Once the diagnosis of XLP is made, aggressive treatment such as rituximab, and other immunosuppressive agents are desired for rapid transition to HSCT. [ABSTRACT FROM AUTHOR]

Alphaviruses are important human and animal pathogens that can cause a range of debilitating symptoms and are found worldwide. These include arthralgic diseases caused by Old-World viruses and encephalitis induced by infection with New-World alphaviruses. Non-coding RNAs do not encode for proteins, but can modulate cellular response pathways in a myriad of ways. There are several classes of non-coding RNAs, some more well-studied than others. Much research has focused on the mRNA response to infection against alphaviruses, but analysis of non-coding RNA responses has been more limited until recently. This review covers what is known regarding host cell non-coding RNA responses in alphavirus infections and highlights gaps in the knowledge that future research should address. [ABSTRACT FROM AUTHOR]

Eastern (EEEV), Venezuelan (VEEV), and western equine encephalitis viruses (WEEV) are members of the genus Alphavirus, family Togaviridae. Typically spread by mosquitoes, EEEV, VEEV, and WEEV induce febrile illness that may develop into more severe encephalitic disease, resulting in myriad severe neurologic sequelae for which there are no vaccines or therapeutics. Here, we summarize the clinical neurologic findings and sequelae induced by these three encephalitic viruses and describe the various animal models available to study them. We emphasize the crucial need for the development of advanced animal modeling combined with the use of telemetry, behavioral testing, and neuroimaging to facilitate a detailed mechanistic understanding of these encephalitic signs and sequelae. Through the use of these systems, much-needed therapeutics and vaccines can be developed. [ABSTRACT FROM AUTHOR]

Jaagsiekte retrovirus (JSRV)-induced ovine pulmonary adenocarcinoma (OPA) is an important ovine respiratory disease in Switzerland. Furthermore, ovine lungs with OPA frequently exhibited lesions suggestive of maedi-visna virus (MVV) or caprine arthritis encephalitis virus (CAEV) infection, indicating that co-morbidities might occur. Lungs and pulmonary lymph nodes were sampled from suspected OPA cases, inflammatory lung lesions and control lungs (total of 110 cases). Tissues were (a) processed for histology and immunohistochemistry (IHC), and (b) underwent DNA extraction and real-time PCR for JSRV, MVV and CAEV. Peptide sequences were used to generate virus-specific customized polyclonal antibodies. PCR-positive OPA cases and formalin-fixed and paraffin-embedded MVV- and CAEV-infected synovial cell pellets served as positive controls. Fifty-two lungs were histologically diagnosed with OPA. Histological evidence of MVV/CAEV infection was detected in 25 lungs. JSRV was detected by PCR in 84% of the suspected OPA cases; six were co-infected with MVV and one with CAEV. MVV was detected by PCR in 14 cases, and four lungs were positive for CAEV. Three lungs had MVV/CAEV co-infection. In IHC, JSRV was detected in 91% of the PCR-positive cases, whereas MVV and CAEV immunoreactivity was seen in all PCR-positive lungs. Although PCR showed a higher sensitivity compared to IHC, the combined approach allows for investigations on viral cell tropism and pathogenic processes in co-morbidities, including their potential interdependency. Furthermore, an immunohistochemical tool for specific differentiation of MVV and/or CAEV infection was implemented. [ABSTRACT FROM AUTHOR]

Herpes simplex virus (HSV) is the most common pathogen of infectious encephalitis, accounting for nearly half of the confirmed cases of encephalitis. Its clinical symptoms are often atypical. HSV PCR in cerebrospinal fluid is helpful for diagnosis, and the prognosis is usually satisfactory after regular antiviral treatment. Interestingly, some patients with recurrent encephalitis have little antiviral effect. HSV PCR in cerebrospinal fluid is negative, but glucocorticoid has a significant effect after treatment. Specific antibodies, such as the NMDA receptor antibody, the GABA receptor antibody, and even some unknown antibodies, can be isolated from cerebrospinal fluid, proving that the immune system contributes to recurrent encephalitis, but the specific mechanism is still unclear. Based on recent studies, we attempt to summarize the relationship between herpes simplex encephalitis and innate immunity, providing more clues for researchers to explore this field further. [ABSTRACT FROM AUTHOR]

Mosquito vectors of eastern equine encephalitis virus (EEEV) and West Nile virus (WNV) in the USA reside within broad multi-species assemblages that vary in spatial and temporal composition, relative abundances and vector competence. These variations impact the risk of pathogen transmission and the operational management of these species by local public health vector control districts. However, most models of mosquito vector dynamics focus on single species and do not account for co-occurrence probabilities between mosquito species pairs across environmental gradients. In this investigation, we use for the first time conditional Markov Random Fields (CRF) to evaluate spatial co-occurrence patterns between host-seeking mosquito vectors of EEEV and WNV around sampling sites in Manatee County, Florida. Specifically, we aimed to: (i) quantify correlations between mosquito vector species and other mosquito species; (ii) quantify correlations between mosquito vectors and landscape and climate variables; and (iii) investigate whether the strength of correlations between species pairs are conditional on landscape or climate variables. We hypothesized that either mosquito species pairs co-occur in patterns driven by the landscape and/or climate variables, or these vector species pairs are unconditionally dependent on each other regardless of the environmental variables. Our results indicated that landscape and bioclimatic covariates did not substantially improve the overall model performance and that the log abundances of the majority of WNV and EEEV vector species were positively dependent on other vector and non-vector mosquito species, unconditionally. Only five individual mosquito vectors were weakly dependent on environmental variables with one exception, Culiseta melanura, the primary vector for EEEV, which showed a strong correlation with woody wetland, precipitation seasonality and average temperature of driest quarter. Our analyses showed that majority of the studied mosquito species' abundance and distribution are insignificantly better predicted by the biotic correlations than by environmental variables. Additionally, these mosquito vector species may be habitat generalists, as indicated by the unconditional correlation matrices between species pairs, which could have confounded our analysis, but also indicated that the approach could be operationalized to leverage species co-occurrences as indicators of vector abundances in unsampled areas, or under scenarios where environmental variables are not informative. [ABSTRACT FROM AUTHOR]

Epstein-Barr virus is a rare ethology of the neurological infections, expressed as encephalitis, aseptic meningitis, Guillain-Barre syndrome or acute demyelinating encephalomyelitis. Most common cases were reported in children, while this infection is rarely described in immunocompetent adults. We present the case of an elderly immunocompetent patient with hypertension and hypothyroidism under treatment who has presented to the emergency department for unusual headache, confusion, sudden loss of consciousness with retrograde amnesia, suddenly onset for 2 hours associated with febrile respiratory symptoms. Traumatic neurological events, cerebral ischemia or metabolic encephalopathies were ruled out, while examination of the cerebrospinal fluid was positive for EpsteinBarr virus. The course of the meningoencephalitis was favourable, although an episode of diarrhoea with Clostridioides difficile with binary positive toxin A+B was notified. The primary infection or the reactivation of a previous infection, is a questionable mechanism of meningoencephalitis with Epstein-Barr virus in an old immunocompetent patient. According to the reported studies, the antiviral treatment with Acyclovir is controversial. The long-term prognosis of acute meningoencephalitis with Epstein-Barr virus is unpredictable and involves careful neurological and onco-haematological monitoring. [ABSTRACT FROM AUTHOR]

Simple Summary: The aims of the present study were to describe the pathology in goats naturally infected with the Spanish goat encephalitis virus (SGEV), as well as discuss the pathogenesis of the disease in the outbreak which occurred in 2011. Neuropathological lesions caused by SGEV were severe and widespread throughout the central nervous system but were more severe and extensive in the proximal cervical spinal cord, medulla oblongata, pons, and cerebellar cortex. The distribution of viral antigens was restricted to the cytoplasm of neurons in several brain areas but not associated with inflammatory foci nor inflammatory cells. SGEV should be considered a significant pathogen of goats that results in severe neurological clinical disease and high mortality. In autumn 2011, a disease outbreak caused by Spanish goat encephalitis virus (SGEV) was reported in a herd of goats from Asturias (north-western Spain), expanding the known geographic distribution of tick-borne encephalitis in Europe. The virus was classified as a new subtype (subspecies) within the Louping-ill virus species of the mammalian tick-borne flavivirus group. The aims of the present study were to describe the pathology in goats naturally infected with SGEV, as well as discuss the pathogenesis of the disease in that outbreak. A total of 22/85 (25.88%) goats (20 adults and 2 kids) died between October 2011 and June 2012, showing neurological clinical signs. Over three years, the mortality rate in the herd reached 100%. Neuropathological lesions caused by SGEV were severe and widespread throughout the central nervous system but were more severe and numerous in the proximal cervical spinal cord, medulla oblongata, pons and cerebellar cortex. They consisted of neuron necrosis, neuronophagia, mononuclear inflammatory cell perivascular cuffs (lymphocytes, plasma cells and macrophages) and gliosis. The distribution of viral antigens was restricted to the cytoplasm of neurons in several brain areas but not associated with inflammatory foci nor inflammatory cells. SGEV should be considered a significant pathogen of goats that results in severe neurological clinical disease and high mortality. [ABSTRACT FROM AUTHOR]

Eastern equine encephalitis virus (EEEV) usually cycles between Culiseta melanura mosquitoes and birds; however, it can also infect humans. EEEV has a positive-sense RNA genome that, in infected cells, serves as an mRNA for the P1234 polyprotein. P1234 undergoes a series of precise cleavage events producing four nonstructural proteins (nsP1–4) representing subunits of the RNA replicase. Here, we report the construction and properties of a trans-replicase for EEEV. The template RNA of EEEV was shown to be replicated by replicases of diverse alphaviruses. The EEEV replicase, on the other hand, demonstrated limited ability in replicating template RNAs originating from alphaviruses of the Semliki Forest virus complex. The replicase of EEEV was also successfully reconstructed from P123 and nsP4 components. The ability of EEEV P123 to form functional RNA replicases with heterologous nsP4s was more efficient using EEEV template RNA than heterologous alphavirus template RNA. This finding indicates that unlike with previously studied Semliki Forest complex alphaviruses, P123 and/or its processing products have a leading role in EEEV template RNA recognition. Infection of HEK293T cells harboring the EEEV template RNA with EEEV or Western equine encephalitis virus prominently activated expression of a reporter encoded in the template RNA; the effect was much smaller for infection with other alphaviruses and not detectable upon flavivirus infection. At the same time, EEEV infection resulted only in a limited activation of the template RNA of chikungunya virus. Thus, cells harboring reporter-carrying template RNAs can be used as sensitive and selective biosensors for different alphaviruses. IMPORTANCE Infection of EEEV in humans can cause serious neurologic disease with an approximately 30% fatality rate. Although human infections are rare, a record-breaking number was documented in 2019. The replication of EEEV has a unique requirement for host factors but is poorly studied, partly because the virus requires biosafety level 3 facilities which can limit the scope of experiments; at the same time, these studies are crucial for developing antiviral approaches. The EEEV trans-replicase developed here contributes significantly to research on EEEV, providing a safe and versatile tool for studying the virus RNA replication. Using this system, the compatibility of EEEV replicase components with counterparts from other alphaviruses was analyzed. The obtained data can be used to develop unique biosensors that provide alternative methods for detection, identification, quantitation, and neutralization of viable alphaviruses that are compatible with high throughput, semiautomated approaches. [ABSTRACT FROM AUTHOR]

The Department of Defense recently began an effort to improve and standardize virus challenge materials and efficacy determination strategies for testing therapeutics and vaccines. This includes stabilization of virus genome sequences in cDNA form where appropriate, use of human-derived virus isolates, and noninvasive strategies for determination of challenge virus replication. Eventually, it is desired that these approaches will satisfy the FDA "Animal Rule" for licensure, which substitutes animal efficacy data when human data are unlikely to be available. To this end, we created and examined the virulence phenotype of cDNA clones of prototypic human infection-derived strains of the alphaviruses, Venezuelan (VEEV INH9813), eastern (EEEV V105) and western (WEEV Fleming) equine encephalitis viruses, and created fluorescent and luminescent reporter expression vectors for evaluation of replication characteristics in vitro and in vivo. Sequences of minimally passaged isolates of each virus were used to synthesize full-length cDNA clones along with a T7 transcription promoter-based bacterial propagation vector. Viruses generated from the cDNA clones were compared with other "wild type" strains derived from cDNA clones and GenBank sequences to identify and eliminate putative tissue culture artifacts accumulated in the cell passaged biological stocks. This was followed by examination of aerosol and subcutaneous infection and disease in mouse models. A mutation that increased heparan sulfate binding was identified in the VEEV INH9813 biological isolate sequence and eliminated from the cDNA clone. Viruses derived from the new human isolate cDNA clones showed similar mouse virulence to existing clone-derived viruses after aerosol or subcutaneous inoculation. [ABSTRACT FROM AUTHOR]

Costa Rica harbors several flaviviruses, including Dengue (DENV), Zika (ZIKV), West Nile virus (WNV), and Saint Louis encephalitis virus (SLEV). While DENV and ZIKV are hyperendemic, previous research indicates restricted circulation of SLEV and WNV in animals. SLEV and WNV seroprevalence and high transmission areas have not yet been measured. To determine the extents of putative WNV and SLEV circulation, we sampled peri-domestic and domestic animals, humans, and mosquitoes in rural households located in two DENV and ZIKV hyperendemic regions during the rainy and dry seasons of 2017–2018 and conducted plaque reduction neutralization test assay for serology (PRNT) and RT-PCR for virus detection. In Cuajiniquil, serological evidence of WNV and SLEV was found in equines, humans, chickens, and wild birds. Additionally, five seroconversion events were recorded for WNV (2 equines), SLEV (1 human), and DENV-1 (2 humans). In Talamanca, WNV was not found, but serological evidence of SLEV circulation was recorded in equines, humans, and wild birds. Even though no active viral infection was detected, the seroconversion events recorded here indicate recent circulation of SLEV and WNV in these two regions. This study thus provides clear-cut evidence for WNV and SLEV presence in these areas, and therefore, they should be considered in arboviruses differential diagnostics and future infection prevention campaigns. [ABSTRACT FROM AUTHOR]

Background: Seizures can occur unpredictably in patients with acute encephalitis syndrome (AES), and many suffer from poor long-term neurological sequelae. Establishing factors associated with acute seizures risk and poor outcomes could support clinical care. We aimed to conduct regional and volumetric analysis of cerebral oedema on magnetic resonance imaging (MRI) in patients with AES. We assessed the relationship of brain oedema with acute seizure activity and long-term neurological outcome. Methods: In a multi-centre cohort study, adults and children presenting with an AES were recruited in the UK. The clinical and brain MRI data were retrospectively reviewed. The outcomes variables were inpatient acute seizure activity and neurological disability at six-months post-discharge. A poor outcome was defined as a Glasgow outcome score (GOS) of 1–3. We quantified regional brain oedema on MRI through stereological examination of T2-weighted images using established methodology by independent and blinded assessors. Clinical and neuroimaging variables were analysed by multivariate logistic regression to assess for correlation with acute seizure activity and outcome. Results: The study cohort comprised 69 patients (mean age 31.8 years; 53.6% female), of whom 41 (59.4%) had acute seizures as inpatients. A higher Glasgow coma scale (GCS) score on admission was a negative predictor of seizures (OR 0.61 [0.46–0.83], p = 0.001). Even correcting for GCS on admission, the presence of cortical oedema was a significant risk factor for acute seizure activity (OR 5.48 [1.62–18.51], p = 0.006) and greater volume of cerebral oedema in these cortical structures increased the risk of acute seizures (OR 1.90 [1.12–3.21], p = 0.017). At six-month post-discharge, 21 (30.4%) had a poor neurological outcome. Herpes simplex virus encephalitis was associated with higher risk of poor outcomes in univariate analysis (OR 3.92 [1.08–14.20], p = 0.038). When controlling for aetiology, increased volume of cerebral oedema was an independent risk factor for adverse neurological outcome at 6 months (OR 1.73 [1.06–2.83], p = 0.027). Conclusions: Both the presence and degree of cerebral oedema on MRIs of patients with AES may help identify patients at risk of acute seizure activity and subsequent long-term morbidity. [ABSTRACT FROM AUTHOR]

Background & Objective: Neurological manifestations were reported in dengue fever. We hypothesize that the diagnosis of DEN virus (DENV) encephalitis based on current clinical diagnostic criteria has been made too liberally. We conducted a systematic review of the literature to clarify this, and to characterize DENV encephalitis better. Methods: We systematically review the literature using MEDLINE and PubMed databases papers published from 1st January 1960 to 31st March 2020. We grouped the cases into definite and probable DENV encephalitis. Definite DENV encephalitis required demonstration of DENV (live virus, viral antigens, RNA) in the central nervous system or CSF whereas probable DENV encephalitis required positive anti-DENV IgM in the CSF and evidence of virus or anti-DENV IgM in the serum. Results: Of the 230 publications obtained from literature search, 121 case reports and series appeared relevant to DENV encephalitis. After applying our inclusion criteria, only 42 cases (34.7%) were acceptable as DENV encephalitis: 30 (24.8%) definite and 12 (9.9%) probable cases. Our findings suggest that DENV encephalitis is more uncommon than previously thought. Part of the reason for non-inclusion may be because many studies relied solely on DENV serology for diagnosis. Cross-reactivities of anti-DENV with anti-JE virus immunoglobulins in serum or CSF occur and this limits their usefulness to distinguish DENV encephalitis from JE. Conclusions: The majority of DENV encephalitis cases reported in the literature did not satisfy a more stringent inclusion criteria. Further investigations including autopsy studies are warranted to better characterize and to understand the pathology and pathogenesis of DENV encephalitis. [ABSTRACT FROM AUTHOR]

The blood brain barrier (BBB) is a multicellular microenvironment that plays an important role in regulating bidirectional transport to and from the central nervous system (CNS). Infections by many acutely infectious viruses such as alphaviruses and flaviviruses are known to impact the integrity of the endothelial lining of the BBB. Infection by Venezuelan Equine Encephalitis Virus (VEEV) through the aerosol route causes significant damage to the integrity of the BBB, which contributes to long-term neurological sequelae. An effective therapeutic intervention strategy should ideally not only control viral load in the host, but also prevent and/or reverse deleterious events at the BBB. Two dimensional monocultures, including trans-well models that use endothelial cells, do not recapitulate the intricate multicellular environment of the BBB. Complex in vitro organ-on-a-chip models (OOC) provide a great opportunity to introduce human-like experimental models to understand the mechanistic underpinnings of the disease state and evaluate the effectiveness of therapeutic candidates in a highly relevant manner. Here we demonstrate the utility of a neurovascular unit (NVU) in analyzing the dynamics of infection and proinflammatory response following VEEV infection and therapeutic effectiveness of omaveloxolone to preserve BBB integrity and decrease viral and inflammatory load. [ABSTRACT FROM AUTHOR]

Alphaviruses are spherical, enveloped RNA viruses primarily transmitted by mosquitoes, and cause significant arthritogenic and neurotropic disease in humans and livestock. Previous reports have shown that—in contrast to prototypical icosahedral viruses—alphaviruses incorporate frequent defects, and these may serve important functions in the viral life cycle. We confirm the genus-wide pleomorphism in live viral particles and extend our understanding of alphavirus assembly through the discovery of an alternate architecture of Eastern equine encephalitis virus (EEEV) particles. The alternate T = 3 icosahedral architecture differs in triangulation number from the classic T = 4 icosahedral organization that typifies alphaviruses, but the alternate architecture maintains the quasi-equivalence relationship of asymmetric units. The fusion spike glycoproteins are more loosely apposed in the T = 3 form with corresponding changes in the underlying capsid protein lattice. This alternate architecture could potentially be exploited in engineering alphavirus-based particles for delivery of alphaviral or other RNA. [ABSTRACT FROM AUTHOR]

The retrovirus causing caprine arthritis encephalitis (CAE), a slowly progressive inflammatory disease in goats, belongs to the group of small ruminant lentiviruses (SRLVs) which cause lifelong infections that ought to be avoided for animal welfare as well as economic reasons. SRLV accreditation has been in place for forty years in The Netherlands and is based on the screening of small ruminant sera for specific antibodies. This paper evaluates 38 dairy goat herds that lost CAEV accreditation between 2012 and 2022. The characteristics of these herds are discussed, and specific follow-up scenarios, depending on desired goals, are introduced. The herd size of the participating herds varies from approximately 400 to 4600 adult dairy goats. The larger herds tended to be more prone to lose herd accreditation and had more difficulties regaining accreditation. Possible routes of introduction are lined up. The Royal GD's tailor-made approach and advice to support livestock farmers with herds that have lost CAE accreditation are discussed in detail. Specific emphasis is placed on the strategic deployment of various diagnostic tests (such as antibody ELISAs and PCR) in different media, such as (pooled) sera, (bulk)milk and tissue samples. Special attention is paid to the added value of retrospective bulk milk testing or the specific testing of groups based on housing and management, which enables the investigation of the moment of viral introduction and route of transmission into a herd. Furthermore, the prospective implementation of bulk milk and strategic pooled milk sample testing in the Dutch SRLV accreditation programs intensifies surveillance and enables the taking of swift action to prevent further transmission within and between herds. An appeal is made to share experiences to improve programs collectively, and to start research into the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Immunoglobulin G antibodies to myelin oligodendrocyte glycoprotein (MOG-IgG) associated disease is a rare, demyelinated disease in the central nerve system (CNS) predominately involving optic nerve, spinal cord, and brain leading to optic neuritis (ON), transverse myelitis (TM), encephalitis. The phenotype of MOG-IgG-associated encephalitis is similar to acute disseminated encephalomyelitis (ADEM) presenting with seizures, abnormal behavioral and psychological symptoms, and cognitive impairment. A few brain biopsies show multiple sclerosis (MS) pattern histopathology with T cells, macrophages, and complement activation. To date, how MOG-IgG is produced is unknown. Herein, we report a case of a 32-year-old male with MOG-IgG-associated encephalitis presenting MOG-IgG in cerebrospinal fluid (CSF) but seronegative, as well as Epstein-Barr virus (EBV) infection and Alzheimer's pathologic change in CSF (Aβ42 = 317 pg/ml, T-Tau = 538 pg/ml, p-Tau =10.09 pg/ml). With a combination treatment of administering intravenous immunoglobulin (0.4 mg/kg/d, 5 days) with a low dose of methylprednisolone (80 mg/d, 5 days) and rituximab (100 mg/week, 3 weeks), the patient recovered significantly after 3 months follow-up. This case provides us with new thoughts into the production of MOG-IgG and the possible pathologic mechanism of MOG-IgG-associated disease (MOG-AD) and simultaneously further confirms the interaction between EBV and changes of CSF biomarkers of Alzheimer's disease (AD). [ABSTRACT FROM AUTHOR]

Previous gag and env sequence studies placed Polish small ruminant lentiviruses (SRLVs) isolated from sheep and goats in subtypes B1, B2, A1, A5, A12, A13, A16–A18, A23, A24 and A27. This study extended the genetic/phylogenetic analysis of previously identified Polish SRLV strains by contributing long terminal repeat (LTR) sequences. A total of 112 samples were analysed. Phylogenetic analyses were carried out on the LTR fragment using the neighbour-joining, maximum likelihood, and unweighted pair group method with arithmetic mean methods. Polish caprine and ovine LTR sequences clustered within group A and grouped in at least 10 clusters (subtypes A1, A5, A12, A13, A16–A18, A23, A24 and A27). Most of the Polish strains (78%) belonged to the same subtype by the indication of the gag, env and LTR genomic regions. Discrepancies in affiliation depending on the particular sequence were observed in 24 (21%) strains, most of which came from mixed-species flocks where more than one SRLV genotype circulated. Sequences of the LTR reflected subtype-specific patterns. Several subtype-specific markers were identified, e.g. a unique substitution of T to A in the fifth position of the TATA box in A17, A27, A20 and B3. This study provides valuable insights into the genetic diversity of SRLV field strains in Poland, their phylogenetic relationships and their position in the recently established SRLV classification. Our results confirmed the existence of the ten subtypes listed and the readier emergence of new SRLV variants in mixed-species flocks. [ABSTRACT FROM AUTHOR]

Small ruminant lentiviruses (SRLV) are chronic and progressive diseases that compromise production, health, and animal welfare. Due to the lack of cure, vaccines, or any effective treatments against SRLV, homeopathy emerges as a low-cost and residue-free approach. This study sought to evaluate the effect of two homeopathic interventions following a triple-blind, placebo-controlled protocol to treat goats displaying SRLV. The Ethical Committee approved all procedures for Animal Use (n° 1988141022). A total of 42 adult Saanen goats (4.6 ± 1.3 years old; 2.6 ± 0.2 body condition score [BCS]; 59.5 ± 8.7 kg) with chronic arthritis and weight loss were included in this study after infection confirmation by PCR and seropositivity by Western Blot to SRLV. The following experimental groups were organized: SRLV living nosode (Gnosode; n=14), Homeopathic (Ghomeopathic; n=14), and Placebo (Gplacebo; n=14). A standard Caprine Lentivirus (CAEV-Cork) sample was used to produce the nosode and prepared by a pharmacy that respected Brazilian requirements. It was stipulated that the 30DH potency does not offer any infectious risk, as verified by PCR analysis, which shows that from 6DH, it is no longer possible to detect the existence of viral particles. After the medicine repertoire that most corresponded to the Materia Medica descriptions, Rhus toxicodendron 12CH, Ledum palustre 5CH, Calcaria carbonica 12CH, Bryonia alba 5CH, and Pulsatila nigricans 30CH were selected to compose the homeopathic complex. Throughout the experimental period, goats were kept under an intensive system, and treatments were administered daily, orally, for 90 days. Every month, all goats underwent a clinical examination, joint ultrasound, and production indices collection. There was a treatment effect (p=0.05) for productive (BCS and live weight) and clinical indices (clinical articular index, crepitation, and width indices). Gnosode and Ghomeopathic showed a greater BCS when compared to Gplacebo (2.7±0.3 = 2.8±0.4 ≤ 2.5±0.3). Ghomeopathic had a greater live weight compared to Gplacebo, even though equal to Gnosode (62.4±11.2 ≤ 57.2±9.5 = 60.4±9.8 kg). In clinical evaluations, Gnosode obtained lower carpal joint indices when compared to Gplacebo, even though equal to Ghomeopathic (8.2±1.7 ≤ 8.7±1.0 = 8.5±1.4 cm). There was also an improvement (p=0.05) for joint ultrasound indices (sagittal and transverse section of the carpus, distance from the joint capsule to the subchondral space, area, and lesion perimeter). Such indices obtained lower values in both treated groups (Gnosode and Ghomeopathic) when compared to Gplacebo as highlighted for the distance from the joint capsule to the subchondral space (6.9±3.3 = 7.6±3.4 ≤ 10.8±4.4 mm), area (137.5±84.4 = 157.9±89.1 ≤ 235.0±90.1 mm) and joint lesion perimeter (81.8±18.8 = 85.7±17.6 ≤ 101.5±15.9 mm). Comparing the joint lesion area from D0 to D90, there was a more than 50% reduction in both treated groups, with an increase of 37.2% in Gplacebo. In conclusion, Gnosode and Ghomeopathic demonstrated promising outcomes in improving arthritic lesions and production rates. Therefore, both medicines can be safely used in goats infected with SRLV, which displays chronic arthritis and weight loss. [ABSTRACT FROM AUTHOR]

The article offers information on the great risk of an incursion of Japanese Encephalitis Virus (JEV) into New Zealand and its potential impact on human and animal populations. Topics include the introduction and rapid spread of JEV genotype IV in Australia since late 2021, the potential modes of entry of the virus into New Zealand, and the implications of infection becoming established in New Zealand, including the need for surveillance and possible vaccination of at-risk populations.

Background: Antibody‐based tests are available for measuring SARS‐CoV‐2‐specific immune responses but fast T‐cell assays remain scarce. Robust T cell‐based tests are needed to differentiate specific cellular immune responses after infection from those after vaccination. Methods: One hundred seventeen individuals (COVID‐19 convalescent patients: n = 40; SARS‐CoV‐2 vaccinees: n = 41; healthy controls: n = 36) were evaluated for SARS‐CoV‐2‐specific cellular immune responses (proliferation, Th1, Th2, Th17, and inflammatory cytokines, activation‐induced marker [AIM] expression) by incubating purified peripheral blood mononuclear cells (PBMC) or whole blood (WB) with SARS‐CoV‐2 peptides (S, N, or M), vaccine antigens (tetanus toxoid, tick borne encephalitis virus) or polyclonal stimuli (Staphylococcal enterotoxin, phytohemagglutinin). Results: N‐peptide mix stimulation of WB identified the combination of IL‐2 and IL‐13 secretion as superior to IFN‐γ secretion to discriminate between COVID‐19‐convalescent patients and healthy controls (p <.0001). Comparable results were obtained with M‐ or S‐peptides, the latter almost comparably recalled IL‐2, IFN‐γ, and IL‐13 responses in WB of vaccinees. Analysis 10 months as opposed to 10 weeks after COVID‐19, but not allergic disease status, positively correlated with IL‐13 recall responses. WB cytokine responses correlated with cytokine and proliferation responses of PBMC. Antigen‐induced neo‐expression of the C‐type lectin CD69 on CD4+ (p <.0001) and CD8+ (p =.0002) T cells informed best about the SARS‐CoV‐2 exposure status with additional benefit coming from CD25 upregulation. Conclusion: Along with N‐ and S‐peptide‐induced IL‐2 and CD69 neo‐expression, we suggest to include the type 2 cytokine IL‐13 as T‐cellular recall marker for SARS‐CoV‐2 specific T‐cellular immune responses after infection and vaccination. [ABSTRACT FROM AUTHOR]

• Viral meningoencephalitis CSF serologic panel did not change antimicrobial therapy. • Immunosuppressive therapies were not delayed while awaiting results of the panel. • Panels did not contribute or add value to the clinical decision making in our cohort. Accurate diagnosis of viral meningoencephalitis (VMe) and identification of the etiologic agent has clinical importance and large serology panels are available to aid in the detection of several viral pathogens. However, such panels are often send-out testing, with prolonged time to results, thus impacting the actionability of test results. We hypothesized these panels may not contribute to patient care and lack clinical utility. A retrospective review of all VMe CSF serology panels ordered at one pediatric (n = 53; 2017–2019) and two adult (n = 200; 2019–2020) tertiary care hospitals was performed to assess test clinical utility. Panels included serology for: Adenovirus, coxsackie and echoviruses, influenza, measles, lymphocytic choriomeningitis virus, herpes simplex virus, mumps, varicella zoster, encephalitis viruses. Clinical data collected included diagnostic test results, symptoms, comorbidities, and interventions. In 129/200 (64.5 %) of adult cases and 37/53 (69.8 %) of pediatric cases CSF had a WBC less than 5 cells/mm2. In total, 127 (63.5 %, 127/200) adult panels had at least one positive target with 49 panels having more than one positive (38.6 %, 49/127). In 99.5 % of adult and 100 % of pediatric cases there was no change to decisions regarding starting, discontinuing, continuing, or changing antimicrobial therapy based on panel results. In no cases were potentially immunosuppressive therapies like steroid or IVIG administration delayed while awaiting the results of the panel. While all patients presented with neurologic symptoms, poor pre-screening for CNS inflammation using CSF WBC analysis likely contributed to poor clinical utility of the VMe panels. Large CSF serologic panels for VMe did not contribute to or add value to clinical decision making in our cohort. [ABSTRACT FROM AUTHOR]

Understanding the interaction between viruses and ecosystems in areas with or without anthropic interference can contribute to the organization of public health services, as well as prevention and disease control. An arbovirus survey was conducted at Caxiuanã National Forest, Pará, Brazil, where 632 local residents, 338 vertebrates and 15,774 pools of hematophagous arthropods were investigated. Neutralization antibodies of the Venezuelan Equine Encephalitis virus, subtype IIIA, Mucambo virus (MUCV) were detected in 57.3% and 61.5% of humans and wild vertebrates, respectively; in addition, genomic fragments of MUCV were detected in pool of Uranotaenia (Ura.) geometrica. The obtained data suggest an enzootic circulation of MUCV in the area. Understanding the circulation of endemic and neglected arboviruses, such as MUCV, represents an important health problem for the local residents and for the people living in the nearby urban centers. [ABSTRACT FROM AUTHOR]

The globalization of mosquito-borne arboviral diseases has placed more than half of the human population at risk. Understanding arbovirus ecology, including the role individual mosquito species play in virus transmission cycles, is critical for limiting disease. Canonical virus-vector groupings, such as Aedes- or Culex-associated flaviviruses, have historically been defined using virus detection in field-collected mosquitoes, mosquito feeding patterns, and vector competence, which quantifies the intrinsic ability of a mosquito to become infected with and transmit a virus during a subsequent blood feed. Herein, we quantitatively synthesize data from 68 laboratory-based vector competence studies of 111 mosquito-virus pairings of Australian mosquito species and viruses of public health concern to further substantiate existing canonical vector-virus groupings and quantify variation within these groupings. Our synthesis reinforces current canonical vector-virus groupings but reveals substantial variation within them. While Aedes species were generally the most competent vectors of canonical "Aedes-associated flaviviruses" (such as dengue, Zika, and yellow fever viruses), there are some notable exceptions; for example, Aedes notoscriptus is an incompetent vector of dengue viruses. Culex spp. were the most competent vectors of many traditionally Culex-associated flaviviruses including West Nile, Japanese encephalitis and Murray Valley encephalitis viruses, although some Aedes spp. are also moderately competent vectors of these viruses. Conversely, many different mosquito genera were associated with the transmission of the arthritogenic alphaviruses, Ross River, Barmah Forest, and chikungunya viruses. We also confirm that vector competence is impacted by multiple barriers to infection and transmission within the mesenteron and salivary glands of the mosquito. Although these barriers represent important bottlenecks, species that were susceptible to infection with a virus were often likely to transmit it. Importantly, this synthesis provides essential information on what species need to be targeted in mosquito control programs. Author summary: There are over 3,500 species of mosquitoes in the world, but only a small proportion are considered important vectors of arboviruses. Vector competence, the physiological ability of a mosquito to become infected with and transmit arboviruses, is used in combination with virus detection in field populations and analysis of vertebrate host feeding patterns to incriminate mosquito species in virus transmission cycles. Here, we quantified the vector competence of Australian mosquitoes for endemic and exotic viruses of public health concern by analyzing 68 laboratory studies of 111 mosquito-virus pairings. We found that Australia has species that could serve as efficient vectors for each virus tested and it is these species that should be targeted in control programs. We also corroborate previously identified virus-mosquito associations at the mosquito genus level but show that there is considerable variation in vector competence between species within a genus. We also confirmed that vector competence is influenced by infection barriers within the mosquito and the experimental protocols employed. The framework we developed could be used to synthesize vector competence experiments in other regions or expanded to a world-wide overview. [ABSTRACT FROM AUTHOR]