Genotypic characterization of Japanese encephalitis virus circulating in swine population of India: Genotype-III still in dominance

Swine is considered as a suitable sentinel to predict Japanese encephalitis virus (JEV) outbreaks in humans. The present study was undertaken to determine the circulating genotypes of JEV in swine population of India. A total of 702 swine serum samples from four states of western, northern, northern-temperate, and north-eastern zones of India were screened by real-time RT-PCR targeting envelope gene of JEV, which showed positivity of 35.33%. The viral copy number ranged from 3 copies to 6.3 × 10⁴ copies/reaction. Subsequently, the capsid/prM structural gene region of JEV positive samples was amplified by nested RT-PCR, sequenced, and genetically characterized. The phylogenetic analysis of the partial sequences of the capsid gene of 42 JEV positive samples showed that they all belonged to genotype-III (G-III) of JEV. Notably, JEV positive swine samples showed high nucleotide identity with human isolates from China and Nepal which explains the probable spillover of infection between neighboring countries probably by migratory birds. The novel mutations were observed in JEV positive sample B8 at C54 position (Phe → Ser), and JEV positive sample K50 at C62 (Thr → Ala) and C65 (Leu → Pro) positions which were absent from other JEV isolates reported till now. The mutation at the C66 position (Leu → Ser) observed in live attenuated vaccine SA14-14-2 strain was not found in JEV positive samples of our study. The detection of the G-III JE virus from climatically diverse states of India reinforces the need to continue the ongoing human vaccination program in India by extending vaccine coverage in temperate states.

Guillain-Barre Syndrome and Antibodies to Arboviruses (Dengue, Chikungunya and Japanese Encephalitis): A Prospective Study of 95 Patients Form a Tertiary Care Centre in Southern India

Objective

The aim of this study was to detect the presence of IgM antibodies against dengue (DEN), chikungunya (CHIK) and Japanese encephalitis (JE) in the serum and CSF of patients with Guillaine-Barre syndrome (GBS).

Methods

GBS patients (>12 years of age) were included after informed consent. Data on history, clinical manifestations, treatment details, and outcome were collected. Serum and CSF were tested for IgM antibodies against DEN, CHIK, and JE.

Results

From April 2018 to December 2019, 95 patients were included in this study. Anti-arboviral IgM antibodies were detected in 30 patients (31.5%) (CSF 11, serum 13, both CSF and serum 6). Serum IgM antibody was present in 19 patients (JE 8, DEN 5, CHIK 2, more than 1 virus 4). Of the 66 patients who underwent CSF studies, antibodies were present in 17 (CHIK 14, DEN 1, more than 1 virus 2). Antibody positivity did not affect the outcome of GBS.

Conclusion

One-third of the GBS patients had evidence of recent infection by arboviruses. This suggests that DEN, CHIK, and JE could be the inciting event for GBS in endemic regions.

Prevalence of vector borne diseases in Jammu Division, Jammu and Kashmir, India

BACKGROUND & OBJECTIVES

Jammu and Kashmir is bestowed upon by great climatic condition favourable for people but the vectors have utilised these conditions to gain access into the state. Vector Borne Diseases (VBDs) were restricted to the spread of malaria and dengue since past two decades, but now, these diseases have widened their geographical reach and in last six years chikungunya, leishmaniasis and Japanese encephalitis have been reported from the state. These VBDs are a threat to thousands of people in the state as they cause huge mortality and morbidity under extreme cases.

METHODS

A hospital-based survey on the VBDs was carried out with the aim of studying the prevalence of major VBD found in the Jammu district taking into account the past records provided by the Directorate of Health Services, Jammu.

RESULTS

The study revealed that malaria, in the past 14 years, has now shown a clear declining trend and dengue cases have shown a very uneven trend with maximum cases in 2013. Leishmaniasis was reported for the first time in the division in 2013, while it was not until 2016 when single case of chikungunya was reported from Jammu division. First outbreak of Japanese encephalitis in the region occurred during 2018 from only Doda district.

INTERPRETATION & CONCLUSION

The present study showed that despite having congenial environmental conditions, Jammu division faces a great threat of VBDs and the increase in the number of cases in future cannot be ruled out. Japanese encephalitis registered its presence for the first time in the division.

Immunogenicity and safety of the third booster dose of the inactivated Japanese encephalitis vaccine in Korean children: A prospective multicenter study

The immunization schedule for the inactivated Japanese encephalitis (JE) vaccine in Korea is a two-dose primary series at 12-24 months of age and three booster doses at 12 months after primary schedule and at 6 and 12 years of age. The aim of this study was to investigate immunogenicity and safety of the third booster dose of the inactivated JE vaccine, as well as the long-term immunogenicity of the second booster dose in Korean children. Healthy children aged 11-13 years, primed and given four doses of inactivated JE vaccines were included. All subjects received the third booster dose of the JE vaccine. Neutralizing antibody (NTAb) titers were assessed before and 4-6 weeks after vaccination using plaque reduction neutralization test (PRNT), and were considered to be protective at ≥ 1:10. Local and systemic adverse events were monitored for 4 weeks after vaccination. Before and after booster vaccination, all seroprotection rates were 100%. Geometric mean titer (GMT) showed a 6.05-fold increase, from 139.11 (95% CI: 110.76, 174.71) to 841.53 (95% CI, 714.25, 991.50). The local tolerability and systemic safety profiles were favorable, with no serious adverse events. In conclusion, the third booster dose of the inactivated JE vaccine was demonstrated to be safe and immunogenic in Korean children when administered according to the current immunization schedule.

Multi-criteria decision analysis to prioritize the introduction of new vaccines in Indonesia by using the framework of the strategic multi-attribute ranking tool for vaccines (SMART vaccines)

Background: Decision-making processes regarding new vaccine prioritizations are complex. The objective of this study was to prioritize the introduction of new vaccines in Indonesia.Methods: A multi-criteria decision analysis (MCDA) was applied in this study. A preliminary data collection form was developed to collect country-specific data in relation to 30 pre-defined attributes. In particular, an open-ended questionnaire was conducted among targeted respondents from global level, national level and vaccine manufacturers, which were involved in the financial flows of new vaccine procurement in Indonesia. For setting new vaccines priorities, targeted respondents were asked to assign weight on 10 selected criteria.Results: Top 3 attributes with the highest weight from respondents were premature deaths averted per year, incident cases prevented per year, and cost-effectiveness. Applying criteria scores and weight assessment, the result showed that PCV, rotavirus, HPV, and JE would be on the 1st, 2nd, 3rd, and 4th rank for setting new vaccine priority in Indonesia. There was a significant difference score (p value <0.05) between all these vaccines.Conclusions: PCV, rotavirus and HPV vaccines should be more prioritized than JE vaccine. This ranking is in line with the WHO's priority list, which potentially illustrates the validity and usefulness of our MCDA-approach.

Association of single nucleotide polymorphisms in TNFA and CCR5 genes with Japanese Encephalitis: A study from an endemic region of North India

TNFA, IL1B, HMGB1, IL10, CXCL8, CCL2 and CCR5 gene polymorphisms were investigated in 183 Japanese Encephalitis (JE) cases and 361 healthy controls from North India. Higher frequency of TNFA rs1800629 G/A, CCR5 rs1799987 genotypes with A allele and lower frequency of combination lacking TNFA rs1800629 A, CCR5 rs333 Δ32, andCCR5 rs1799987 A alleles and CCL2 rs1024611 G/G genotype was observed in JE cases. TNFA rs1800629 A and CCR5 rs1799987 A alleles were associated with susceptibility while combination lacking TNFA rs1800629 A, CCR5 rs333 Δ32, and rs1799987 A alleles and CCL2 rs1024611 G/G genotype was associated with protection to JE.

[Acute meningitis and encephalitis syndrome surveillance disease burden in four China prefectures]

Objectives: To explore acute meningitis and encephalitis syndrome (AMES) surveillance in 4 China prefectures, to understand the epidemiological features and disease burden of neisseria meningitides (Nm) meningitis, streptococcus pneumoniae (Sp) meningitis, haemophilus influenza type b (Hib) meningitis and Japanese encephalitis and provide evidence for related disease prevention and control. Methods: AMES surveillance were conducted in Jinan, Shandong Province and Yichang, Hubei Province in September 2006, and in 13 districts of Shijiazhuang, Hebei Province and Guigang City, Guangxi Zhuang Autonomous Region in April 2007. Six hospitals in each city were selected as monitoring pilot hospitals to carry out reports of suspected cases of acute meningitis and encephalitis, case investigation, blood specimens and cerebrospinal fluid specimen collection, anti-JEV IgM antibody enzyme-linked immunosorbent assay, Nm, Sp and Hib culture and polymerase chain reaction detection, etc. According to the age group, the incidence of bacterial meningitis and Japanese encephalitis in local residents <20 years old was estimated. Results: From 2006 to 2013, a total of 19 423 surveillance cases were reported in four cities, of which 11 071 (56.99%) were reported in the pilot hospitals. Of the 11 071 cases, 5 315 were tested for bacteriology and 9 180 were tested for anti-JEV IgM antibodies. Among the bacteriological tests, 176 cases were positive, including 75 cases of Nm positive, 91 cases of Sp positive and 10 cases of Hib positive. The incidence of three bacterial meningitis is estimated for people under 20 years old, with estimated incidence of Nm, Sp and Hib meningitis in children <5 years old was 0.46/100 000-0.71/100 000, 0.34/100 000-0.83/100 000 and 0.32/100 000-0.57/100 000 respectively; the estimated incidence of Nm and Sp meningitis in children aged 5-9 years was 0.59/100 000-1.14/100 000 and 0.50/100 000-1.66/100 000 respectively. In 732 cases of positive JE cases, the positive detection rates of <5 years old, 40-49 years old and ≥50 years old were 9.51% (95/999), 28.09% (66/235) and 33.85% (130/384), respectively. The estimated annual incidence rate of JE was 0.12/100 000-0.79/100 000.ratio of cases 1.19∶1. Most of cases (27.30%) were children and adolescents aged 5-14 years and those (26.84%) aged over 45 year. Conclusion: The study found that primary and secondary school students are the key population of Nm meningitis, suggesting that it is necessary to explore the enhanced immunization study of meningococcal vaccine in this population; Sp has the possibility of occurrence in all age groups; <5 years old children are the main population of Hib meningitis.

Changes of Epidemiological Characteristics of Japanese Encephalitis Viral Infection and Birds as a Potential Viral Transmitter in Korea

Japanese encephalitis (JE) cases have been increasingly reported recently especially in Seoul and its vicinity. Pigs are known as amplifying host of JE virus (JEV), but do not play an important role in these recent events because pig-breeding is not common in Seoul. The distribution and the density of migratory birds are correlated with JE cases in cities and they might be highly potential hosts contributing to transmit JEV in metropolitan areas. JE genotype and sero-prevalence in birds should be determined for the verification of the transmission route of JEV in the recent sporadic occurrence of JE cases in Seoul.

Comparison of clinical and laboratory characteristics during two major paediatric meningitis outbreaks of echovirus 30 and other non-polio enteroviruses in Germany in 2008 and 2013

Viral meningitis is mainly caused by non-polio enteroviruses (NPEV). Large-scale data on the clinical characteristics between different outbreaks within the same region are lacking. This study aimed to analyse a possible influence of the circulating NPEV genotype on the disease outcome of affected children. A retrospective cohort study analysing two major outbreaks of NPEV meningitis in Germany in 2008 and 2013 was conducted in cooperation with the National Reference Centre for Poliomyelitis and Enteroviruses (NRC PE) and five German children's hospitals. A total of 196 patients with laboratory-confirmed NPEV meningitis were enrolled. In 2008, children with NPEV meningitis had significantly higher fever and showed more behavioural changes and less back pain. To better define typical findings in echovirus 30 (E-30) meningitis, patients were split into the following three groups: E-30 positive patients, patients with "Non E-30" infection and patients with "Untyped" NPEV infection. E-30 positive patients were significantly older and their disease course was more acute, with early admission to but also early discharge from hospital. E-30 positive patients showed a significantly higher rate of headache and meningism, and a lower rate of diarrhoea and clinically defined septicaemia when compared to the others. Regarding laboratory testing, E-30 positive patients presented with significantly elevated peripheral blood neutrophil counts when compared to patients with "Non E-30" or "Untyped" NPEV infection. In conclusion, E-30 meningitis in children shows a characteristic pattern of clinical features. To further characterise NPEV strains worldwide, continuous surveillance and typing of NPEV strains causing central nervous system disease is warranted.

Cerebrospinal Fluid Biomarkers of Japanese Encephalitis

Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia. Acute encephalitis syndrome (AES) is a group of central nervous system (CNS) disorders caused by a wide range of viruses, bacteria, fungi, chemicals and toxins. It is important to distinguish between various forms of infectious encephalitis with similar clinical manifestations in order to ensure specific and accurate diagnosis and development of subsequent therapeutic strategies. Cerebrospinal fluid (CSF) is in direct contact with the CNS and hence it is considered to be an excellent source for identifying biomarkers for various neurological disorders. With the recent advancement in proteomic methodologies, the field of biomarker research has received a remarkable boost.  The present study identifies potential biomarkers for JE using a proteomics based approach. The CSF proteomes from ten patients each with JE and Non-JE acute encephalitis were analyzed by 2D gel electrophoresis followed by mass spectrometry. Vitamin D-binding protein (DBP), fibrinogen gamma chain, fibrinogen beta chain, complement C4-B, complement C3 and cytoplasmic actin were found to be significantly elevated in case of JE indicating severe disruption of the blood brain barrier and DBP can be suggested to be an important diagnostic marker.

Phylogenetic analysis of poly and non structural protein in Japanese Encephalitis virus with other related viral families

BACKGROUND

Japanese encephalitis (JE) causes inflammation of brain. The mortality rate due to JE is 30% while 10 -15 % of patients make full recovery. The disease spreads through infected mosquito bites breeding in rice fields and feeds on pigs, birds, and ducks.

PURPOSE

As proteins show important structure to function relationship the study was designed to carry out the identification of poly and non-structural proteins in the infective virus group using different strains of Japanese encephalitis virus i.e. JAOARS982, Nakayama Strain SA (V), Strain SA-14.

METHODS

With reference to non structural proteins we obtained protein sequences of the following Japanese encephalitis virus groups: Japanese encephalitis virus, Weatnile virus, Kunjin virus. Further comparative and phylogenetic analysis was performed to explore evolutionary relationship among these groups.

RESULTS

Results of phylogeny of alignment score was found to be 375184 using multiple alignment, Jal view, ClustalW (1.83) and ClustalW2. However, the analysis among the non-structural proteins of Japanese Encephalitis Virus, Westnile Virus, and Kunjin Virus revealed the phylogeny alignment score to be 875 through multiple sequence alignment and Tree view respectively.

CONCLUSION

Phylogenetic analysis revealed that these four strains are interrelated as well as showing high similarity with the other viruses of this group due to conserved regions among their sequences.