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Indian Pediatrics Apr 1988
Review
Topics: Diagnosis, Differential; Encephalitis, Japanese; Humans; India
PubMed: 2852173
DOI: No ID Found -
PloS One 2018Japanese encephalitis virus (JEV) is a major cause of encephalitis in Asia, and the commonest cause of mosquito-borne encephalitis worldwide. Detection of JEV RNA... (Review)
Review
Development of an improved RT-qPCR Assay for detection of Japanese encephalitis virus (JEV) RNA including a systematic review and comprehensive comparison with published methods.
BACKGROUND
Japanese encephalitis virus (JEV) is a major cause of encephalitis in Asia, and the commonest cause of mosquito-borne encephalitis worldwide. Detection of JEV RNA remains challenging due to the characteristic brief and low viraemia, with 0-25% of patients positive, and the mainstay of diagnosis remains detection of anti-JEV IgM antibody.
METHODS
We performed a systematic review of published RT-PCR protocols, and evaluated them in silico and in vitro alongside new primers and probes designed using a multiple genome alignment of all JEV strains >9,000nt from GenBank, downloaded from the NCBI website (November 2016). The new assays included pan-genotype and genotype specific assays targeting genotypes 1 and 3.
RESULTS
Ten RT-qPCR assays were compared, a pre-existing in-house assay, three published assays and six newly designed assays, using serial RNA dilutions. We selected three assays, one published and two novel assays, with the lowest limit of detection (LOD) for further optimisation and validation. One of the novel assays, detecting NS2A, showed the best results, with LOD approximately 4 copies/ reaction, and no cross-reaction on testing closely related viruses in the JEV serocomplex, West Nile Virus and St. Louis Virus. The optimised assays were validated in consecutive patients with central nervous system infections admitted to hospitals in Laos, testing paired CSF and serum samples.
CONCLUSIONS
We succeeded in developing a JEV specific RT-qPCR assay with at least 1 log10 improved sensitivity as compared to existing assays. Further evaluation is required, field-testing the assay in a larger group of patients.
Topics: Asia; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction
PubMed: 29570739
DOI: 10.1371/journal.pone.0194412 -
Epidemiological investigation of swine Japanese encephalitis virus based on RT-RAA detection method.Scientific Reports Jun 2022JEV is one of the zoonotic pathogens that cause serious diseases in humans. JEV infection can cause abortion, mummified foetus and stillbirth in sows, orchitis and semen...
JEV is one of the zoonotic pathogens that cause serious diseases in humans. JEV infection can cause abortion, mummified foetus and stillbirth in sows, orchitis and semen quality decline in boars, causing huge economic losses to pig industry. In order to investigate the epidemiology of JEV in pigs in Sichuan province, a rapid and efficient fluorescent Reverse transcription recombinase-aided amplification (RT-RAA) detection method was established. Aborted fetuses and testicular swollen boar samples were detected by RT-RAA in pigs in the mountain areas around Sichuan Basin, and the detection rate of JEV was 6.49%. The positive samples were identified as JEV GI strain and GIIIstrain by sequencing analysis. We analyzed the whole gene sequence of a positive sample for the GI virus. The Envelope Protein (E protein) phylogenetic tree analysis was far related to the Chinese vaccine strain SA14-14-2, and was most closely related to the JEV GI strains SH17M-07 and SD0810 isolated from China. The results showed that we established an efficient, accurate and sensitive method for clinical detection of JEV, and JEV GI strains were prevalent in Sichuan area. It provides reference for the prevention and control of JEV in Sichuan.
Topics: Animals; Encephalitis Virus, Japanese; Encephalitis, Japanese; Female; Genotype; Male; Phylogeny; Pregnancy; Semen Analysis; Swine; Swine Diseases
PubMed: 35672440
DOI: 10.1038/s41598-022-13604-4 -
Vector Borne and Zoonotic Diseases... Dec 2023Japanese encephalitis virus (JEV) is a mosquito-borne zoonotic flavivirus and the leading cause of pediatric encephalitis in the Asian Pacific region. The transmission...
Japanese encephalitis virus (JEV) is a mosquito-borne zoonotic flavivirus and the leading cause of pediatric encephalitis in the Asian Pacific region. The transmission cycle primarily involves spp. mosquitoes and Ardeid birds, with domestic pigs () being the source of infectious viruses for the spillover of JEV from the natural endemic transmission cycle into the human population. Although many studies have concluded that domestic pigs play an important role in the transmission cycle of JEV, and infection of humans, the role of feral pigs in the transmission of JEV remains unclear. Since domestic and feral pigs are the same species, and because feral pig populations in the United States are increasing and expanding geographically, the current study aimed to test the hypothesis that if JEV were introduced into the United States, feral pigs might play a role in the transmission cycle. Sinclair miniature pigs, that exhibit the feral phenotype, were intradermally inoculated with JEV genotype Ib. These pigs were derived from crossing miniature domestic pig with four strains of feral pigs and were used since obtaining feral swine was not possible. The Sinclair miniature pigs became viremic and displayed pathological outcomes similar to those observed in domestic swine. Based on these findings, we conclude that in the event of JEV being introduced into the United States, feral pig populations could contribute to establishment and maintenance of a transmission cycle of JEV and could lead to the virus becoming endemic in the United States.
Topics: Animals; Swine; Humans; Child; Encephalitis Virus, Japanese; Encephalitis, Japanese; Swine, Miniature; Birds; Culex; Culicidae; Phenotype
PubMed: 37672628
DOI: 10.1089/vbz.2023.0030 -
Neurology India Jan 2024
Review
Topics: Humans; Encephalitis, Japanese; Encephalitis; Infections; Chronic Disease; Recurrence
PubMed: 38443035
DOI: 10.4103/neurol-india.Neurol-India-D-23-00465 -
Emerging Infectious Diseases Jan 2018Japanese encephalitis virus (JEV) is a mosquitoborne virus endemic to China and Southeast Asia that causes severe encephalitis in <1% of infected persons. Transmission...
Japanese encephalitis virus (JEV) is a mosquitoborne virus endemic to China and Southeast Asia that causes severe encephalitis in <1% of infected persons. Transmission of JEV via blood transfusion has not been reported. We report transmission of JEV via blood donation products from an asymptomatic viremic donor to 2 immunocompromised recipients. One recipient on high-dose immunosuppressive drugs received JEV-positive packed red blood cells after a double lung transplant; severe encephalitis and a poor clinical outcome resulted. JEV RNA was detected in serum, cerebrospinal fluid, and bronchoalveolar lavage fluid specimens. The second recipient had leukemia and received platelets after undergoing chemotherapy. This patient was asymptomatic; JEV infection was confirmed in this person by IgM seroconversion. This study illustrates that, consistent with other pathogenic flaviviruses, JEV can be transmitted via blood products. Targeted donor screening and pathogen reduction technologies could be used to prevent transfusion-transmitted JEV infection in highly JEV-endemic areas.
Topics: Blood Transfusion; Disease Outbreaks; Encephalitis Virus, Japanese; Encephalitis, Japanese; Hong Kong; Humans; Immunocompromised Host; Magnetic Resonance Imaging; Male; Middle Aged; Neuroimaging; Phylogeny; Polymerase Chain Reaction; Sequence Analysis, DNA
PubMed: 29043965
DOI: 10.3201/eid2401.171297 -
Australian Family Physician Jun 2001A young couple come to see you for a pretravel consultation. They are planning to spend a month backpacking in Thailand over December and January. They have read about...
A young couple come to see you for a pretravel consultation. They are planning to spend a month backpacking in Thailand over December and January. They have read about Japanese encephalitis in travel books and seek your advice on the need for vaccination against this disease.
Topics: Encephalitis, Japanese; Endemic Diseases; Humans; Thailand; Travel; Vaccination
PubMed: 11458591
DOI: No ID Found -
Australian Veterinary Journal Nov 2003
Topics: Animals; Australia; Culex; Encephalitis, Japanese; Horses; Humans; Insect Vectors; Sentinel Surveillance; Swine
PubMed: 15086103
DOI: No ID Found -
Zoonoses and Public Health May 2024No autochthonous human cases of Japanese encephalitis (JE) have been reported to date in the European Union (EU). In this study, we assess the likelihood of Japanese...
BACKGROUND AND OBJECTIVE
No autochthonous human cases of Japanese encephalitis (JE) have been reported to date in the European Union (EU). In this study, we assess the likelihood of Japanese encephalitis virus (JEV) introduction and transmission within the EU and propose outbreak response measures.
RISK ASSESSMENT
Given the global geographical distribution of JEV, the probability of virus introduction into the EU is currently very low, with viremic bird migration being the most plausible pathway of introduction. However, this likelihood would significantly increase if the virus were to become established in the Middle East, Caucasus, Central Asia or Africa. Considering the environmental conditions that are expected to be conducive for virus circulation, there is a high likelihood of virus transmission within the EU after its introduction in environmentally suitable areas. The spread of the virus within the EU would likely occur through the movement of wild birds, pigs and mosquitoes.
MITIGATION
To mitigate or potentially contain the emergence of JE in the EU, early detection of both human and animal cases will be crucial.
Topics: Animals; Humans; Swine; Encephalitis, Japanese; European Union; Encephalitis Virus, Japanese; Culicidae; Birds; Swine Diseases
PubMed: 38110840
DOI: 10.1111/zph.13103 -
Indian Pediatrics Oct 1984
Topics: Child; Child, Preschool; Encephalitis, Japanese; Female; Humans; India; Infant; Male
PubMed: 6098560
DOI: No ID Found