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Indian Journal of Pediatrics Oct 2023The study compared the clinical profile and outcomes of Japanese encephalitis (JE) and acute encephalitis syndrome (AES) in children. Fifty-six consecutive children with...
The study compared the clinical profile and outcomes of Japanese encephalitis (JE) and acute encephalitis syndrome (AES) in children. Fifty-six consecutive children with symptoms fulfilling the WHO clinical case definition of AES from June 2018 to June 2020 were included in the study. All patients who tested positive for either serum or cerebrospinal fluid (CSF) anti-JE-IgM antibodies were JE patients (n = 24) and compared with non-JE AES cases (n = 32). Fever, seizures, and altered sensorium were the most common presenting symptoms. Low GCS, status epilepticus, meningeal irritation, raised CSF protein, and INR > 1.5 of JE children showed significant association with mortality (p value < 0.05), whereas only low GCS showed significant association in non-JE AES cases. The JE-specific mortality rate was 29%, which was less than the mortality rate of non-JE AES children at 41%. Both JE and non-JE AES children had a similar clinical profile, but only the JE children's poor clinical and laboratory parameters were associated with adverse outcomes.
Topics: Child; Humans; Encephalitis, Japanese; Acute Febrile Encephalopathy; Seizures; Fever; Status Epilepticus; Antibodies, Viral
PubMed: 36765003
DOI: 10.1007/s12098-022-04424-5 -
Sensors (Basel, Switzerland) Aug 2020A highly effective way to improve prognosis of viral infectious diseases and to determine the outcome of infection is early, fast, simple, and efficient diagnosis of... (Review)
Review
A highly effective way to improve prognosis of viral infectious diseases and to determine the outcome of infection is early, fast, simple, and efficient diagnosis of viral pathogens in biological fluids. Among a wide range of viral pathogens, attract a special attention. genus includes more than 70 viruses, the most familiar being dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV). Haemorrhagic and encephalitis diseases are the most common severe consequences of flaviviral infection. Currently, increasing attention is being paid to the development of electrochemical immunological methods for the determination of . This review critically compares and evaluates recent research progress in electrochemical biosensing of DENV, ZIKV, and JEV without labelling. Specific attention is paid to comparison of detection strategies, electrode materials, and analytical characteristics. The potential of so far developed biosensors is discussed together with an outlook for further development in this field.
Topics: Biosensing Techniques; Dengue; Encephalitis, Japanese; Flavivirus; Humans; Zika Virus; Zika Virus Infection
PubMed: 32824351
DOI: 10.3390/s20164600 -
PLoS Neglected Tropical Diseases Aug 2022Thailand has introduced a nationwide vaccination against Japanese encephalitis virus (JEV) into National Immunization Programme since the 1990's. To improve the...
BACKGROUND
Thailand has introduced a nationwide vaccination against Japanese encephalitis virus (JEV) into National Immunization Programme since the 1990's. To improve the understanding of immunity and susceptibility of the population after 28 years of a vaccination programme, we conducted a JEV seroepidemiological study in a JEV-endemic area of Thailand.
METHODS
An age-stratified, population-based, seroepidemiological study was conducted in Chiang Mai, Thailand-a northern Thai province where is an endemic area of Japanese encephalitis. Nine districts were chosen based on administrative definition: rural (n = 3); urban (n = 3); and peri-urban (n = 3). Within each district, eligible participants were randomly selected from 3 age groups: adolescents (10-20 years); adults (21-50 years); and older adults/elderly (≥51 years) by computer randomization. Plaque reduction neutralization tests (PRNT50 and PRNT90) were performed to measure neutralizing antibodies to JEV. To account for the cross-reactivity of JEV and other flaviviruses, JEV seroprotection was defined according to age, previous history of JEV vaccination, and PRNT50/PRNT90 levels of study participants.
RESULTS
Overall, 279 adolescents, 297 adults, and 297 older adults/elderly were enrolled from nine districts. Age-stratified, protocol-defined, cluster-adjusted JEV seroprotection rates were 61% (95% CI: 48-73%), 43% (95% CI: 31-57%), and 52% (95% CI: 37-67%) for adolescents, adults, and older adults/elderly, respectively. Living in peri-urban districts, having a history of prior dengue virus infection, and previously receiving mouse brain-derived JEV vaccine were significantly associated with seroprotection to JEV in adolescents. Older age and male sex were associated with seroprotection for adults; and only male sex was the associated factor for older adults/elderly (P <0.05).
CONCLUSIONS
Approximately half of population living in a JEV-endemic area demonstrated seroprotection to JEV. Ongoing nationwide surveillance on JEV seropepidemiology is an important strategy to understand the evolving population-level immunity to JEV, and to help formulating the appropriate recommendations on JE immunization.
Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Japanese Encephalitis Vaccines; Male; Mice; Seroepidemiologic Studies; Vaccination
PubMed: 35913983
DOI: 10.1371/journal.pntd.0010674 -
PLoS Neglected Tropical Diseases Aug 2014Japanese encephalitis (JE) is arguably one of the most serious viral encephalitis diseases worldwide. China has a long history of high prevalence of Japanese... (Review)
Review
Japanese encephalitis (JE) is arguably one of the most serious viral encephalitis diseases worldwide. China has a long history of high prevalence of Japanese encephalitis, with thousands of cases reported annually and incidence rates often exceeding 15/100,000. In global terms, the scale of outbreaks and high incidence of these pandemics has almost been unique, placing a heavy burden on the Chinese health authorities. However, the introduction of vaccines, developed in China, combined with an intensive vaccination program initiated during the 1970s, as well as other public health interventions, has dramatically decreased the incidence from 20.92/100,000 in 1971, to 0.12/100,000 in 2011. Moreover, in less readily accessible areas of China, changes to agricultural practices designed to reduce chances of mosquito bites as well as mosquito population densities have also been proven effective in reducing local JE incidence. This unprecedented public health achievement has saved many lives and provided valuable experience that could be directly applicable to the control of vector-borne diseases around the world. Here, we review and discuss strategies for promotion and expansion of vaccination programs to reduce the incidence of JE even further, for the benefit of health authorities throughout Asia and, potentially, worldwide.
Topics: China; Encephalitis, Japanese; Humans; Immunization Programs; Japanese Encephalitis Vaccines; Prevalence; Public Health; Time Factors; Vaccination
PubMed: 25121596
DOI: 10.1371/journal.pntd.0003015 -
Microbiology Spectrum Aug 2022Pigs are the amplifying hosts of Japanese encephalitis virus (JEV). Currently, the safe and effective live attenuated vaccine made of JEV strain SA14-14-2, which does...
Pigs are the amplifying hosts of Japanese encephalitis virus (JEV). Currently, the safe and effective live attenuated vaccine made of JEV strain SA14-14-2, which does not express NS1', is widely used in humans and domestic animals to prevent JEV infection. In this study, we constructed the NS1' expression recombinant virus (rA66G) through a single nucleotide mutation in of JEV strain SA14-14-2. Animal experiments showed that NS1' significantly enhanced JEV infection in pig central nervous system (CNS) and tonsil tissues. Pigs shed virus in oronasal secretions in the JEV rA66G virus inoculation group, indicating that NS1' may facilitate the horizontal transmission of JEV. Additionally, dendritic cells (DCs) and macrophages are the main target cells of JEV infection in pig tonsils, which are an important site of persistent JEV infection. The reduction of major histocompatibility complex class II (MHC II) and activation of inducible nitric oxide synthase (iNOS) in pig tonsils caused by viral infection may create a beneficial environment for persistent JEV infection. These results are of significance for JEV infection in pigs and lay the foundation for future studies of JEV persistent infection in pig tonsils. Pigs are amplification hosts for Japanese encephalitis virus (JEV). JEV can persist in the tonsils for months despite the presence of neutralizing antibodies. The present study shows that NS1' increases JEV infection in pig tonsils. In addition, DCs and macrophages in the tonsils are the target cells for JEV infection, and JEV NS1' promotes virus infection in DCs and macrophages. This study reveals a novel function of JEV NS1' protein and lays the foundation for future studies of JEV persistent infection in pig tonsils.
Topics: Animals; Cell Line; Dendritic Cells; Encephalitis Virus, Japanese; Encephalitis, Japanese; Macrophages; Palatine Tonsil; Swine; Vaccines, Attenuated
PubMed: 35730942
DOI: 10.1128/spectrum.01147-22 -
Archives of Virology Mar 2022Japanese encephalitis (JE) is a zoonotic epidemic disease caused by Japanese encephalitis virus (JEV), and currently, no medicines are available to treat this disease....
Japanese encephalitis (JE) is a zoonotic epidemic disease caused by Japanese encephalitis virus (JEV), and currently, no medicines are available to treat this disease. Autophagy modulators play an important role in the treatment of tumors, heart disease, and some viral diseases. The aim of this study was to investigate the effects of autophagy modulators on JEV infection and the host response in mice. The experimental mice were grouped as follows: DMEM (control), JEV, JEV+rapamycin (JEV+Rapa), JEV+wortmannin (JEV+Wort), JEV+chloroquine (JEV+CQ), Rapa, Wort, and CQ. The control group was treated with DMEM. The mice in other groups were infected with 10 PFU of JEV, and Rapa, Wort, and CQ were administered 2 h prior to JEV challenge and then administered daily for 10 consecutive days. All mice were monitored for neurological signs and survival. The damage of subcellular structures in the mouse brain was evaluated by transmission electron microscopy. The distribution of virus in the mouse brain was determined by RNAScope staining and immunohistochemical staining. The neuroinflammatory responses in the brain were examined via quantitative real-time PCR, and the signal pathways involved in neuroinflammation were identified by Western blot. The mice in the JEV+Wort and JEV+CQ groups showed milder neurological symptoms, less damage to the mitochondria in the brain tissue, and a higher survival rate than those in the JEV+Rapa and JEV groups. Compared with the JEV+Rapa and JEV groups, the distribution of JEV in the brain of mice in the JEV+Wort and JEV+CQ groups was lower, and the inflammatory response was weaker. No significant difference was observed in the expression of the PI3K/AKT/NF-κB pathway in mouse brain among the different groups. Our study suggests that the autophagy inhibitors Wort and CQ reduce JEV infection and weaken the inflammatory response, which does not depend on the PI3K/AKT/NF-κB pathway in mouse brain.
Topics: Animals; Autophagy; Encephalitis Virus, Japanese; Encephalitis, Japanese; Inflammation; Mice; Phosphatidylinositol 3-Kinases
PubMed: 35119507
DOI: 10.1007/s00705-021-05283-9 -
Zoonoses and Public Health Feb 2022Japanese encephalitis virus (JEV) infection has been recognized as a serious disease in humans. Wildlife animal infections due to JEV have not been well described. This...
Japanese encephalitis virus (JEV) infection has been recognized as a serious disease in humans. Wildlife animal infections due to JEV have not been well described. This study identified JEV infection in two deceased meerkats in Thailand, with clinical signs of neurological disease. Histopathology of brains revealed severe lymphoplasmacytic necrotizing meningoencephalitis, while similar inflammation was observed in the lung and liver. Partial JEV sequences were identified from the formalin-fixed paraffin-embedded-derived brain sections of two meerkats and were found to be genetically similar to a JEV strain detected in China but not from a local strain. Using immunohistochemistry, the virus was identified in neurons and glial cells, and also found in bronchial glands, Kupffer's cells in liver, lymphocytes in the spleen and pancreatic acini, which suggests extraneural infection. Transmission electron microscopy confirmed the presence of spheroid viral particles in the lungs. These findings may suggest that infection of extraneural organs in meerkats is similar to that described in JEV-infected humans. In conclusion, this study identified the first JEV infection in meerkats as an interesting case study. The JEV should be considered as an important differential diagnosis in meerkats with encephalitis. Further surveillance on JEV infection in meerkats and other wildlife species in a large cohort is needed in the future study.
Topics: Animals; Brain; China; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Immunohistochemistry
PubMed: 34254456
DOI: 10.1111/zph.12882 -
PLoS Neglected Tropical Diseases Nov 2022A fatal case of Japanese encephalitis (JE) occurred in a resident of the Tiwi Islands, in the Northern Territory of Australia in February 2021, preceding the large JE...
BACKGROUND
A fatal case of Japanese encephalitis (JE) occurred in a resident of the Tiwi Islands, in the Northern Territory of Australia in February 2021, preceding the large JE outbreak in south-eastern Australia in 2022. This study reports the detection, whole genome sequencing and analysis of the virus responsible (designated JEV/Australia/NT_Tiwi Islands/2021).
METHODS
Reverse transcription quantitative PCR (RT-qPCR) testing was performed on post-mortem brain specimens using a range of JE virus (JEV)-specific assays. Virus isolation from brain specimens was attempted by inoculation of mosquito and mammalian cells or embryonated chicken eggs. Whole genome sequencing was undertaken using a combination of Illumina next generation sequencing methodologies, including a tiling amplicon approach. Phylogenetic and selection analyses were performed using alignments of the Tiwi Islands JEV genome and envelope (E) protein gene sequences and publicly available JEV sequences.
RESULTS
Virus isolation was unsuccessful and JEV RNA was detected only by RT-qPCR assays capable of detecting all JEV genotypes. Phylogenetic analysis revealed that the Tiwi Islands strain is a divergent member of genotype IV (GIV) and is closely related to the 2022 Australian outbreak virus (99.8% nucleotide identity). The Australian strains share highest levels of nucleotide identity with Indonesian viruses from 2017 and 2019 (96.7-96.8%). The most recent common ancestor of this Australian-Indonesian clade was estimated to have emerged in 2007 (95% HPD range: 1998-2014). Positive selection was detected using two methods (MEME and FEL) at several sites in the E and non-structural protein genes, including a single site in the E protein (S194N) unique to the Australian GIV strains.
CONCLUSION
This case represents the first detection of GIV JEV acquired in Australia, and only the second confirmed fatal human infection with a GIV JEV strain. The close phylogenetic relationship between the Tiwi Islands strain and recent Indonesian viruses is indicative of the origin of this novel GIV lineage, which we estimate has circulated in the region for several years prior to the Tiwi Islands case.
Topics: Animals; Humans; Encephalitis Virus, Japanese; Phylogeny; Encephalitis, Japanese; Genotype; Encephalitis Viruses, Japanese; Nucleotides; Northern Territory; Mammals
PubMed: 36409739
DOI: 10.1371/journal.pntd.0010754 -
The American Journal of Tropical... Dec 2020Although previous studies have reported that meteorological factors might affect the risk of Japanese encephalitis (JE), the relationship between meteorological factors...
Although previous studies have reported that meteorological factors might affect the risk of Japanese encephalitis (JE), the relationship between meteorological factors and JE remains unclear. This study aimed to evaluate the relationship between meteorological factors and JE and identify the threshold temperature. Daily meteorological data and JE surveillance data in Dazhou, Sichuan, were collected for the study period from 2005 to 2012 (restricting to May-October because of the seasonal distribution of JE). A distributed lag nonlinear model was used to analyze the lagged and cumulative effect of daily average temperature and daily rainfall on JE transmission. A total of 622 JE cases were reported over the study period. We found JE was positively associated with daily average temperature and daily rainfall with a 25-day lag and 30-day lag, respectively. The threshold value of the daily average temperature is 20°C. Each 5°C increase over the threshold would lead to a 13% (95% CI: 1-17.3%) increase in JE. Using 0 mm as the reference, a daily rainfall of 100 mm would lead to a 132% (95% CI: 73-311%) increase in the risk of JE. Japanese encephalitis is climate-sensitive; meteorological factors should be taken into account for the future prevention and control measure making, especially in a warm and rainy weather condition.
Topics: Adolescent; Adult; Child; Child, Preschool; China; Encephalitis, Japanese; Female; Humans; Humidity; Male; Meteorological Concepts; Nonlinear Dynamics; Rain; Temperature
PubMed: 33124540
DOI: 10.4269/ajtmh.20-0040 -
Expert Opinion on Therapeutic Targets 2015Japanese encephalitis (JE) remains a public health threat in Asia. Although several vaccines have been licensed, ∼ 67,900 cases of the disease are estimated to occur... (Review)
Review
INTRODUCTION
Japanese encephalitis (JE) remains a public health threat in Asia. Although several vaccines have been licensed, ∼ 67,900 cases of the disease are estimated to occur annually, probably because the vaccine coverage is low. Therefore, effective antiviral drugs are required to control JE. However, no licensed anti-JE drugs are available, despite extensive efforts to develop them.
AREAS COVERED
We provide a general overview of JE and JE virus, including its transmission cycle, distribution, structure, replication machinery, immune evasion mechanisms and vaccines. The current situation in antiviral drug development is then reviewed and future perspectives are discussed.
EXPERT OPINION
Although the development of effective anti-JE drugs is an urgent issue, only supportive care is currently available. Recent progress in our understanding of the viral replication machinery and immune evasion strategies has identified new targets for anti-JE drug development. To date, most candidate drugs have only been evaluated in single-drug formulations, and efficient drug delivery to the CNS has virtually not been considered. However, an effective anti-JE treatment is expected to be achieved with multiple-drug formulations and a targeted drug delivery system in the near future.
Topics: Animals; Antiviral Agents; Drug Delivery Systems; Drug Design; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Japanese Encephalitis Vaccines; Virus Replication
PubMed: 26156208
DOI: 10.1517/14728222.2015.1065817