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Rhode Island Medical Journal (2013) Aug 2020Travelers to 24 endemic countries in Asia may be at risk for Japanese encephalitis. The ACIP has recently expanded guidelines on the use of Ixiaro, the inactivated... (Review)
Review
Travelers to 24 endemic countries in Asia may be at risk for Japanese encephalitis. The ACIP has recently expanded guidelines on the use of Ixiaro, the inactivated Japanese encephalitis vaccine. This article reviews the disease burden of Japanese encephalitis and the role of a travel clinic in guiding travelers to Asia regarding decision-making about the use of this highly protective vaccine.
Topics: Adolescent; Adult; Asia; Child; Child, Preschool; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Infant; Japanese Encephalitis Vaccines; Risk; Seasons; Travel
PubMed: 32752568
DOI: No ID Found -
Human Vaccines & Immunotherapeutics 2014Japanese encephalitis (JE) is an infectious disease of the central nervous system caused by Japanese encephalitis virus (JEV), a zoonotic mosquito-borne flavivirus. JEV... (Review)
Review
Japanese encephalitis (JE) is an infectious disease of the central nervous system caused by Japanese encephalitis virus (JEV), a zoonotic mosquito-borne flavivirus. JEV is prevalent in much of Asia and the Western Pacific, with over 4 billion people living at risk of infection. In the absence of antiviral intervention, vaccination is the only strategy to develop long-term sustainable protection against JEV infection. Over the past half-century, a mouse brain-derived inactivated vaccine has been used internationally for active immunization. To date, however, JEV is still a clinically important, emerging, and re-emerging human pathogen of global significance. In recent years, production of the mouse brain-derived vaccine has been discontinued, but 3 new cell culture-derived vaccines are available in various parts of the world. Here we review current aspects of JEV biology, summarize the 4 types of JEV vaccine, and discuss the potential of an infectious JEV cDNA technology for future vaccine development.
Topics: Animals; Asia; Cell Line; Drug Discovery; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Japanese Encephalitis Vaccines; Technology, Pharmaceutical; Vaccination
PubMed: 24161909
DOI: 10.4161/hv.26902 -
The American Journal of Tropical... May 2023Japanese encephalitis (JE) is becoming an increasingly important issue among adults. The reasons for this are multifactorial. During the past decades, new areas of... (Review)
Review
Japanese encephalitis (JE) is becoming an increasingly important issue among adults. The reasons for this are multifactorial. During the past decades, new areas of Japanese encephalitis virus (JEV) transmission have occurred in several locations, most notably in a markedly expanded area of Australia during 2021-2022. When JEV enters new areas, cases in adults frequently occur. This is unlike the typical pattern in endemic areas where the burden of disease is in children because most adults are protected through natural immunity following earlier exposure to the virus. Even in endemic areas, JEV has become relatively more important in adults because improved JE control through childhood immunization programs has resulted in a substantial decrease in pediatric JE cases and thus more prominence of adult JE cases. Finally, increases in tourism to JE risk areas have resulted in more exposure of adult travelers, who are usually non-immune, to infection in JE risk areas. In this review we describe the increasing importance of JE in adults in some areas and then consider the comparative clinical presentation and severity of illness among children and adults.
Topics: Adult; Child; Humans; Encephalitis, Japanese; Encephalitis Virus, Japanese; Australia; Immunity, Innate; Immunization Programs; Japanese Encephalitis Vaccines
PubMed: 37037440
DOI: 10.4269/ajtmh.23-0036 -
Journal of Special Operations Medicine... 2016
Review
Topics: Asia; Encephalitis, Japanese; Endemic Diseases; Humans; Japanese Encephalitis Vaccines; Military Personnel
PubMed: 27450609
DOI: No ID Found -
Annali Di Igiene : Medicina Preventiva... 2024Japanese encephalitis, caused by the JE virus transmitted by mosquitoes, is the most common type of epidemic encephalitis in Asia. It is endemic in most of South and... (Review)
Review
Japanese encephalitis, caused by the JE virus transmitted by mosquitoes, is the most common type of epidemic encephalitis in Asia. It is endemic in most of South and Southeast Asia, but the number of cases can vary greatly between areas. While many infections do not lead to disease, the symptomatic cases can be very severe and life-threatening. It mainly affects children, whereas adults are generally immune to the disease due to either being infected in childhood or receiving vaccination. However, individuals who are not immune, such as travelers from non-endemic countries, are susceptible to the disease when exposed to the virus for the first time, regardless of age. Without antiviral treatment options, vaccination is the only strategy to establish effective protection against Japanese encephalitis.
Topics: Adult; Child; Animals; Humans; Encephalitis, Japanese; Asia; Vaccination; Culicidae
PubMed: 38436079
DOI: 10.7416/ai.2024.2616 -
Australian Journal of General Practice May 2023Japanese encephalitis virus (JEV) is a mosquito-borne arbovirus endemic to the Asia-Pacific that causes high morbidity and mortality in those who develop symptomatic... (Review)
Review
BACKGROUND
Japanese encephalitis virus (JEV) is a mosquito-borne arbovirus endemic to the Asia-Pacific that causes high morbidity and mortality in those who develop symptomatic disease. Prior to 2021, only five locally acquired cases had been detected in Australia, all in northern Australia. Following a sentinel case in 2021, widespread dissemination of JEV was detected in northern and south-eastern Australia, accompanied by an increase in locally acquired cases, which have been detected as far south as Victoria. This expansion has occurred in the setting of warmer and wetter conditions under the influence of climate change.
OBJECTIVE
To provide Australian general practitioners (GPs) an overview of JEV, given its recent expansion, and the potential for sustained endemicity.
DISCUSSION
As the distribution of JEV expands under the influence of climate change, Australian GPs need to be familiar with this condition, especially those practicing in rural areas and where detections have occurred.
Topics: Animals; Humans; Climate Change; Encephalitis Virus, Japanese; Encephalitis, Japanese; Victoria
PubMed: 37149766
DOI: 10.31128/AJGP-07-22-6484 -
The Indian Journal of Medical Research 2022Japanese encephalitis (JE) is a leading cause of viral encephalitis in Southeast Asia. It is a serious public health issue in India, and cases have been emerging in... (Review)
Review
Japanese encephalitis (JE) is a leading cause of viral encephalitis in Southeast Asia. It is a serious public health issue in India, and cases have been emerging in newer areas of the country. Although vaccination efforts have already been initiated in the country since 2006 and later through the Universal Immunization Programme in 2011, still a significant reduction in the number of cases has to be achieved since an escalating trend of JE incidence has been reported in certain States such as Assam, Uttar Pradesh and West Bengal. Moreover, fresh cases of JE have been reported from certain pockets in Odisha as well. Despite the mass JE vaccination programme implemented in prioritized endemic zones in the country in 2011, a shift in the age group of JE virus (JEV) infection was noticed affecting the adult population in West Bengal. The recent detection of the circulation of genotype I (GI) in Gorakhpur, Uttar Pradesh and the co-circulation of GI and genotype III (GIII) in West Bengal are probably a warning signal for the public health personnel to strengthen the surveillance system in all endemic hotspots in the country. The abrupt emergence of JEV genotype V (GV) in China and Korea in 2009, after its first detection in Malaya in 1952, endemic countries have been cautioned to strengthen their surveillance, because GV has been suspected of getting dispersed efficiently in other parts of Asia. Moreover, the reduced protection efficiency of the JEV GIII-based vaccine against the JEV genotype V further warrants careful evaluation of the ongoing vaccination strategies in the endemic countries, anticipating the possible incursion of GV and its impact on future control strategies. In view of the above facts, the present communication reviews the current knowledge on the molecular epidemiology of JEV in India vis-a-vis the global scenario and discusses the future priorities in JEV research in India for effectively designing control strategies.
Topics: Adult; Humans; Encephalitis Virus, Japanese; Encephalitis, Japanese; India; Asia; Genotype
PubMed: 36926775
DOI: 10.4103/ijmr.IJMR_2606_19 -
Journal of Magnetic Resonance Imaging :... 1998Japanese encephalitis (JE) is an acute encephalomyelitis which is a primary viral encephalitis accompanying a viral infection. Clinically, the patient who either resides... (Review)
Review
Japanese encephalitis (JE) is an acute encephalomyelitis which is a primary viral encephalitis accompanying a viral infection. Clinically, the patient who either resides in an endemic region or who has been exposed to the viral vector (mosquito) may have symptoms including high fever, headache, and impaired consciousness. JE involves many portions of the supratentorial and infratentorial compartments including the brain stem, hippocampus, thalamus, basal ganglia, and white matter. Classically MR imaging demonstrates the lesions of JE as hyperintense on T2-weighted images and hypointense on T1-weighted images. Hemorrhagic transformations have also been described in JE lesions, with corresponding expected T1 and T2 changes. Differential considerations based on the MRI appearance are somewhat broad, including but not limited to primary viral encephalitis, acute encephalopathy, limbic encephalitis, and acute disseminated encephalomyelitis. The therapy for JE is primarily conservative and supportive since there is no specific treatment for JE, and the disease has a high fatality rate. The prognosis depends on the extent of involvement at primary presentation, and on the autoimmune mechanisms of this disease.
Topics: Adult; Aged; Child; Diagnosis, Differential; Encephalitis, Japanese; Female; Humans; Incidence; Japan; Magnetic Resonance Imaging; Male; Tomography, X-Ray Computed
PubMed: 9702874
DOI: 10.1002/jmri.1880080402 -
Nature Reviews. Neurology Apr 2018Japanese encephalitis is a mosquito-borne disease that occurs in Asia and is caused by Japanese encephalitis virus (JEV), a member of the genus Flavivirus. Although many... (Review)
Review
Japanese encephalitis is a mosquito-borne disease that occurs in Asia and is caused by Japanese encephalitis virus (JEV), a member of the genus Flavivirus. Although many flaviviruses can cause encephalitis, JEV causes particularly severe neurological manifestations. The virus causes loss of more disability-adjusted life years than any other arthropod-borne virus owing to the frequent neurological sequelae of the condition. Despite substantial advances in our understanding of Japanese encephalitis from in vitro studies and animal models, studies of pathogenesis and treatment in humans are lagging behind. Few mechanistic studies have been conducted in humans, and only four clinical trials of therapies for Japanese encephalitis have taken place in the past 10 years despite an estimated incidence of 69,000 cases per year. Previous trials for Japanese encephalitis might have been too small to detect important benefits of potential treatments. Many potential treatment targets exist for Japanese encephalitis, and pathogenesis and virological studies have uncovered mechanisms by which these drugs could work. In this Review, we summarize the epidemiology, clinical features, prevention and treatment of Japanese encephalitis and focus on potential new therapeutic strategies, based on repurposing existing compounds that are already suitable for human use and could be trialled without delay. We use our newly improved understanding of Japanese encephalitis pathogenesis to posit potential treatments and outline some of the many challenges that remain in tackling the disease in humans.
Topics: Animals; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans
PubMed: 29697099
DOI: 10.1038/nrneurol.2018.30 -
Advances in Virus Research 2003
Review
Topics: Animals; Culicidae; Encephalitis, Japanese; Female; Humans; India; Insect Vectors; Japan; Male; Pregnancy; Risk Factors; Seasons; Travel
PubMed: 14714431
DOI: 10.1016/s0065-3527(03)61003-1