Diagnostic markers of acute encephalitis syndrome and COVID-associated multisystem inflammatory syndrome in children from Southern India.

Acute encephalitis syndrome (AES) in children poses a significant public health challenge in India. This study aims to explore the utility of host inflammatory mediators and neurofilament (NfL) levels in distinguishing etiologies, assessing disease severity, and predicting outcomes in AES. We assessed 12 mediators in serum (n = 58) and 11 in cerebrospinal fluid (CSF) (n = 42) from 62 children with AES due to scrub typhus, viral etiologies, and COVID-associated multisystem inflammatory syndrome (MIS-C) in Southern India. Additionally, NfL levels in serum (n = 20) and CSF (n = 18) were examined. Clinical data, including Glasgow coma scale (GCS) and Liverpool outcome scores, were recorded. Examining serum and CSF markers in the three AES etiology groups revealed notable distinctions, with scrub typhus differing significantly from viral and MIS-C causes. Viral causes had elevated serum CCL11 and CCL2 compared with scrub typhus, while MIS-C cases showed higher HGF levels than scrub typhus. However, CSF analysis showed a distinct pattern with the scrub typhus group exhibiting elevated levels of IL-1RA, IL-1ß, and TNF compared with MIS-C, and lower CCL2 levels compared with the viral group. Modeling the characteristic features, we identified that age ≥3 years with serum CCL11 < 180 pg/mL effectively distinguished scrub typhus from other AES causes. Elevated serum CCL11, HGF, and IL-6:IL-10 ratio were associated with poor outcomes (p = 0.038, 0.005, 0.02). Positive CSF and serum NfL correlation, and negative GCS and serum NfL correlation were observed. Median NfL levels were higher in children with abnormal admission GCS and poor outcomes. Measuring immune mediators and brain injury markers in AES provides valuable diagnostic insights, with the potential to facilitate rapid diagnosis and prognosis. The correlation between CSF and serum NfL, along with distinctive serum cytokine profiles across various etiologies, indicates the adequacy of blood samples alone for assessment and monitoring. The association of elevated levels of CCL11, HGF, and an increased IL-6:IL-10 ratio with adverse outcomes suggests promising avenues for therapeutic exploration, warranting further investigation.

Association of Scrub Typhus in Children with Acute Encephalitis Syndrome and Meningoencephalitis, Southern India.

Scrub typhus is an established cause of acute encephalitis syndrome (AES) in northern states of India. We systematically investigated 376 children with AES in southern India, using a stepwise diagnostic strategy for the causative agent of scrub typhus, Orientia tsutsugamushi, including IgM and PCR testing of blood and cerebrospinal fluid (CSF) to grade its association with AES. We diagnosed scrub typhus in 87 (23%) children; of those, association with AES was confirmed in 16 (18%) cases, probable in 55 (63%), and possible in 16 (18%). IgM detection in CSF had a sensitivity of 93% and specificity of 82% compared with PCR. Our findings suggest scrub typhus as an emerging common treatable cause of AES in children in southern India and highlight the importance of routine testing for scrub typhus in diagnostic algorithms. Our results also suggest the potential promise of IgM screening of CSF for diagnosis of AES resulting from scrub typhus.

A two-step process for in silico screening to assess the performance of qRTPCR kits against variant strains of SARS-CoV-2.

BACKGROUND: Since inception of the COVID-19 pandemic, early detection and isolation of positive cases is one of the key strategies to restrict disease transmission. Real time reverse transcription polymerase chain reaction (qRTPCR) has been the mainstay of diagnosis. Most of the qRTPCR kits were designed against the target genes of original strain of SARS-CoV-2. However, with the emergence of variant strains of SARS-CoV-2, sensitivity of the qRTPCR assays has reportedly reduced. In view of this, it is critical to continuously monitor the performance of the qRTPCR kits in the backdrop of variant strains of SARS-CoV-2. Real world monitoring of assay performance is challenging. Therefore, we developed a two-step in-silico screening process for evaluating the performance of various qRTPCR kits used in India. RESULTS: We analysed 73 qRT-PCR kits marketed in India, against the two SARS-CoV-2 VoCs. Sequences of both Delta (B.1.617.2) and Omicron (B.1.1.529) VoCs submitted to GISAID within a specific timeframe were downloaded, clustered to identify unique sequences and aligned with primer and probe sequences. Results were analysed following a two-step screening process. Out of 73 kits analysed, seven were unsatisfactory for detection of both Delta and Omicron VoCs, 10 were unsatisfactory for Delta VoC whereas 2 were unsatisfactory for only Omicron VoC. CONCLUSION: Overall, we have developed a useful screening process for evaluating the performance of qRTPCR assays against Delta and Omicron VoCs of SARS-CoV-2 which can be used for detecting SARS-CoV-2 VoCs that may emerge in future and can also be redeployed for other evolving pathogens of public health importance.

Infection of human microglial cell line CHME-3 to study neuropathogenesis of chikungunya virus.

Chikungunya virus (CHIKV) infection, generally characterised by fever, rash and debilitating polyarthralgia, and/or arthritis, also causes complications of the central nervous system, including encephalitis. However, the role of microglial cells in the neuropathogenesis of CHIKV is poorly understood. The current study characterised the progression of CHIKV infection in the human microglial cell line CHME-3. The susceptibility of these cells to CHIKV and the viral replication kinetics were assessed during the early and late phases of infection. The cell viability was determined using the cell viability assay. Ultrastructural changes in CHIKV infected CHME-3 cells were assessed using transmission electron microscopy. The results showed that CHME-3 cells are susceptible to CHIKV infection and support viral replication with no significant loss in cell viability until 72 h post infection. Ultrastructural studies revealed the formation of cytopathic vacuoles-I (CPV-I) in the early stages and CPV-II in later stages with several virions organized along the membrane of CPV-II. Profuse vacuolation was observed in the later stages of infection. Abnormal giant mitochondria with altered cristae were observed in infected cells with an electron-dense matrix. The study establishes CHME-3 cells as a potential model for investigating the role of human microglial cells in neuropathogenicity of CHIKV.

Antecedent infections in Guillain-Barré syndrome patients from south India.

Guillain-Barré syndrome (GBS) is the commonest post-infectious inflammatory peripheral neuropathy with undiscerned aetiology. The commonly reported antecedent infections implicated in India include Campylobacter jejuni, chikungunya, dengue, and Japanese encephalitis (JE). In this study from south India, we investigated the role of these four agents in triggering GBS. This case-control study was performed on 150 treatment-naive patients with GBS and 150 age and sex-matched controls from the same community. IgM immunoreactivity for C. jejuni, chikungunya, and dengue was detected by enzyme-linked immunosorbent assay (ELISA) in serum of patients with GBS and control subjects. Immunoreactivity against JE was detected in serum as well as cerebrospinal fluid (CSF) from patients (n = 150) and orthopaedic control (n = 45) subjects. The immunoreactivity against infections was compared between demyelinating and axonal subtypes of GBS. Overall, 119/150 patients with GBS had serological evidence of antecedent infection. Amongst those with evidence of antecedent infection, 24 (16%), 8 (5%), and 9 (6%) patients were exclusively immunoreactive to chikungunya, JE, and C. jejuni, respectively. In the remaining patients (78/119), immunoreactivity to multiple pathogens was noted. Immunoreactivity to C. jejuni infection was found in 32% of GBS patients compared to 2.7% controls (P < .001), whereas to chikungunya virus was reported in 66.7% of patients with GBS compared to 44.7% controls (P = .006). Anti-dengue immunoreactivity was significantly associated with the demyelinating subtype of GBS. Patients positive for JE IgM (CSF) manifested demyelinating electrophysiology. In this large case-control study, immunoreactivity against multiple infectious agents was observed in a subset of patients. Chikungunya was the commonest antecedent infection, followed by C. jejuni.

Chikungunya Virus Interacts with Heat Shock Cognate 70 Protein to Facilitate Its Entry into Mosquito Cell Line.

AIM: The study was designed to identify putative Chikungunya virus (CHIKV) receptor/s on C6/36 cells that facilitate viral entry. METHODS: The virus overlay protein binding assay (VOPBA) was adopted to identify CHIKV-interacting bands present in C6/36 cell membrane and identity of the protein was established by mass spectrometry. The role of this protein as a putative CHIKV receptor on C6/36 cells was confirmed by infection inhibition assay. Cell surface localization of the identified protein was studied by indirect immunofluorescence assay (IFA) on nonpermeabilized cells and by flow cytometry. Interaction between this protein and CHIKV was confirmed by co-immunoprecipation (Co-IP) and Western blotting. The effect of depletion of the identified protein by quercetin was demonstrated by infection inhibition assay. RESULTS: A 70-kDa protein was identified as a CHIKV-interacting protein by VOPBA. MALDI-TOF analysis followed by homology search revealed that this protein could be heat shock cognate 70 (HSC 70). Anti-HSC 70 antibodies blocked CHIKV entry into C6/36 cells in a dose-dependent manner. IFA and flow cytometry analysis demonstrated HSC 70 localization on C6/36 cell surface. Co-IP experiments confirmed the interaction between HSC 70 and CHIKV envelope. Quercetin- and YM-01-treated C6/36 cells exhibited dose-dependent infection inhibition. CONCLUSION: HSC 70 serves as a putative CHIKV receptor on C6/36 cells.

Correlation of plasma viral loads and presence of Chikungunya IgM antibodies with cytokine/chemokine levels during acute Chikungunya virus infection.

Chikungunya (CHIKV) is an emerging arboviral infection of public health concern in India contributing to widespread morbidity. The precise molecular events occurring early in the infection have not been well understood. Cytokines/chemokines are suspected to play a key role in its pathogenesis. Very few studies have correlated the plasma levels of cytokines/chemokines with diagnostic markers such as viral loads and presence of CHIKV IgM antibodies. Understanding these dynamics in the early phase of CHIKV infection is likely to provide an insight into the evolution of the immune response, identify biomarkers for assessing severity, and for development of newer therapeutic strategies. This study was therefore undertaken to estimate the levels of various cytokines/chemokines in plasma samples of patients infected with CHIKV and correlate to viral load and CHIKV IgM antibodies. Cytokine/chemokine levels and viral loads in plasma were measured using cytometric bead array and TaqMan real time PCR assay, respectively. The findings revealed that acute phase of CHIKV infection is characterized by predominant inflammatory responses mediated by IL-6, IL-8, IP-10, MCP-1, and MIG (P < 0.003). Plasma levels of IL-6 (r = 0.53, P < 0.05) and MCP-1 (r = 0.83, P < 0.05) emerged as reliable biomarkers of high viral loads in Chikungunya patients. Further, presence of elevated levels of MCP-1 and MIG during the chronic phase of the disease suggests that these chemokines may contribute to perpetuation of symptoms. Hence, these chemokines might serve as targets for the development of treatment to ameliorate the symptoms during the acute phase and prevent the development of chronic manifestations.

Correction: Contact tracing of COVID-19 in Karnataka, India: Superspreading and determinants of infectiousness and symptomatic infection.

[This corrects the article DOI: 10.1371/journal.pone.0270789.].

Association of neurotropic viruses in HIV-infected individuals who died of secondary complications of tuberculosis, cryptococcosis, or toxoplasmosis in South India.

The frequencies of 10 opportunistic DNA viruses were determined by multiplex real-time PCR in paired cerebrospinal fluid (CSF) and brain tissue of HIV-infected individuals. In the CSF, viruses were detectable in 45/55 cases: JC virus (JCV) in 62%, Epstein-Barr virus (EBV) in 44%, cytomegalovirus (CMV) in 25%, varicella-zoster virus (VZV) in 3.6%, herpes simplex virus 1 (HSV-1) in 1.8%, and human herpesvirus 6 (HHV-6) in 1.8% of cases. A single virus was detectable in 20 cases, 19 cases had coinfection with two viruses, and 6 cases were positive for three viruses. JCV was detectable in the CSF of 62% of cases and in 42% of brain tissues, with higher loads in progressive multifocal leukoencephalopathy (PML) (P < 0.05).

An ultrastructural and genomic study on the SARS-CoV-2 variant B.1.210 circulating during the first wave of COVID-19 pandemic in India.

PURPOSE: The study aims to isolate and understand cytopathogenesis, ultrastructure, genomic characteristics and phylogenetic analysis of SARS-CoV-2 virus of B.1.210 lineage, that circulated in India during first wave of the pandemic. METHODS: Clinical specimen from an interstate traveller from Maharashtra to Karnataka, in May 2020, who was positive by RT PCR for SARS-CoV-2 infection was subjected to virus isolation and Whole Genome Sequencing. Vero cells were used to study cytopathogenesis and ultrastructural features by Transmission Electron Microscopy (TEM). Phylogenetic analysis of the whole genome sequences of several SARS-CoV-2 variants downloaded from GISAID was performed in comparison with the B.1.210 variant identified in this study. RESULTS: The virus was isolated in Vero cells and identified by immunofluorescence assay and RT PCR. The growth kinetics in infected Vero cells revealed a peak viral titre at 24 â€‹h post-infection. Ultrastructural studies revealed distinct morphological changes with accumulation of membrane-bound vesicles containing pleomorphic virions in the cytoplasm, with single or multiple intranuclear filamentous inclusions and dilated rough endoplasmic reticulum with viral particles. Whole genome sequence of the clinical specimen as well as the isolated virus revealed the virus to be of lineage B.1.210 with the D614G mutation in the spike protein. Phylogenetic analysis of the whole genome sequence in comparison with other variants reported globally revealed that the isolated SARS-CoV-2 virus of lineage B.1.210 is closely related to the original Wuhan virus reference sequence. CONCLUSIONS: The SARS-CoV-2 variant B.1.210 virus isolated here showed ultrastructural features and cytopathogenesis similar to that of the virus reported during early phase of pandemic. Phylogenetic analysis showed that the isolated virus is closely related to the original Wuhan virus, thereby suggesting that the SARS-CoV-2 lineage B.1.210 that was circulating in India during the early phase of pandemic is likely to have evolved from the original Wuhan strain.

Utility of IgM ELISA, TaqMan real-time PCR, reverse transcription PCR, and RT-LAMP assay for the diagnosis of Chikungunya fever.

Chikungunya fever a re-emerging infection with expanding geographical boundaries, can mimic symptoms of other infections like dengue, malaria which makes the definitive diagnosis of the infection important. The present study compares the utility of four laboratory diagnostic methods viz. IgM capture ELISA, an in house reverse transcription PCR for the diagnosis of Chikungunya fever, TaqMan real-time PCR, and a one step reverse transcription-loop mediated isothermal amplification assay (RT-LAMP). Out of the 70 serum samples tested, 29 (41%) were positive for Chikungunya IgM antibody by ELISA and 50 (71%) samples were positive by one of the three molecular assays. CHIKV specific nucleic acid was detected in 33/70 (47%) by reverse transcription PCR, 46/70 (66%) by TaqMan real-time PCR, and 43/70 (62%) by RT-LAMP assay. A majority of the samples (62/70; 89%) were positive by at least one of the four assays used in the study. The molecular assays were more sensitive for diagnosis in the early stages of illness (2-5 days post onset) when antibodies were not detectable. In the later stages of illness, the IgM ELISA is a more sensitive diagnostic test. In conclusion we recommend that the IgM ELISA be used as an initial screening test followed one of the molecular assays in samples that are collected in the early phase of illness and negative for CHIKV IgM antibodies. Such as approach would enable rapid confirmation of the diagnosis and implementation of public health measures especially during outbreaks.

COVID-19: a boon or a bane for the microbiologists.

BACKGROUND: In the situation where COVID-19 pandemic has placed unprecedented demands and pressure on the health care system, we wanted to analyze how the medical microbiologists of our country were affected. Was it actually an opportunity to showcase the specialty or was it a doom? A debate was organized as a key session in the national e-conference of the Indian Association of Medical Microbiologists, held on 10 December 2020. OBJECTIVES: The objective of the debate was to examine and analyze the various positive as well as negative impacts of COVID-19 on the discipline of the medical microbiology of our country. CONTENT: Before the debate a voting session was conducted to assess the opinion of the audience followed by a very interesting debate where both the speakers presented their view points. The points in favor of the discipline were, mainly up-gradation of the specialty of microbiology in terms of learning, skill development, infrastructure, networking & research opportunities related to COVID-19. While the main points against were, nerve wracking work load without much acknowledgement, performance pressure from hospital administration to maintain rapid turnaround time, and a forceful neglect of all other infectious diseases like tuberculosis and antimicrobial resistance which were the key battle fields of the medical microbiologists. Postgraduate & even undergraduate training programs got completely derailed to their disadvantage. By the end of the debate, it was concluded that COVID-19 was neither a boon nor a bane to the microbiologists. A balanced approach to the problem in hand is required without ignoring the pre-existing infectious diseases in our country. The post debate voting swayed the audience considerably for it to be a bane & the faculty debating for boon had a huge margin to begin with but finally won with a whisker indicating the intensity of the debate.

Acid and Alkaline Phosphatases Specific activities and Expression as Biomarkers in Brain Tumor Grading and Correlation of Anaplastic Oligodendroglioma G-III to Meningiomas G-I among Brain Tumors and their primary culture.

BACKGROUND: Acid Phosphatase (ACP) and Alkaline Phosphatases (ALP) are hydrolases that remove phosphate groups from protein and nucleic acid respectively for regulation of cell function from ACP as lysosomal defence function and ALP membrane-bound as a barrier of the cell. The ACP and ALP-specific activities of Meningiomas (n = 75) and gliomas (n = 81) were compared among brain tumors, normal brain, and derived primary cell culture. METHODS: Total Protein and Phosphatases assays estimated by Spectrophotometer and Native PAGE Gel Electrophoresis. Brain tumor and primary explant lysosome studies were performed with an electron microscope. RESULTS: Average ACP specific activity exhibited 9.32617 ± 4.1144 for meningiomas (n = 55) and 5.91 ± 5.8305 for gliomas (n = 60) respectively as compared to normal brain 7.104 ± 1.33 (n = 120) nm/min/mg of protein. Average ALP exhibited 37.1862 ± 39.91 (n = 36) for meningiomas and 5.91 ± 5.83 (n = 60) for gliomas respectively as compared to normal brain (n = 117) 2.463 ± 1.01 nm/min/mg of protein. ACP and ALP exhibited higher activities for meningiomas but not for gliomas as compared to normal brain, in contrast, both expressed more activities in the majority of glioma cell lines and lower in meningioma cell lines. Interestingly gliomas exhibited similar average specific activities for ACP and ALP. While GBM IV exhibits lower ALP activities due to cell migration and higher ACP activity correlate too many storage lysosomes from Electron microscopic observation as compared to meningiomas. CONCLUSIONS: Higher ALP activities can be surrogate markers from meningiomas G-I, G-II to G-III respectively. However meningiomas G-III are similar to gliomas excluding Anaplastic Oligodendroglioma G- III which is similar to Meningiomas G-I even for cells growth patterns. Therefore, an ALP level in meningiomas indicates complementary diagnosis as antibody-ALP conjugates with anticancer drugs for efficiency in targeting brain tumor reduction.

External quality assessment of COVID-19 real time reverse transcription PCR laboratories in India.

Sudden emergence and rapid spread of COVID-19 created an inevitable need for expansion of the COVID-19 laboratory testing network across the world. The strategy to test-track-treat was advocated for quick detection and containment of the disease. Being the second most populous country in the world, India was challenged to make COVID-19 testing available and accessible in all parts of the country. The molecular laboratory testing network was augmented expeditiously, and number of laboratories was increased from one in January 2020 to 2951 till mid-September, 2021. This rapid expansion warranted the need to have inbuilt systems of quality control/ quality assurance. In addition to the ongoing inter-laboratory quality control (ILQC), India implemented an External Quality Assurance Program (EQAP) with assistance from World Health Organization (WHO) and Royal College of Pathologists, Australasia. Out of the 953 open system rRTPCR laboratories in both public and private sector who participated in the first round of EQAP, 891(93.4%) laboratories obtained a passing score of > = 80%. The satisfactory performance of Indian COVID-19 testing laboratories has boosted the confidence of the public and policy makers in the quality of testing. ILQC and EQAP need to continue to ensure adherence of the testing laboratories to the desired quality standards.

Impact of Antecedent Infections on the Antibodies against Gangliosides and Ganglioside Complexes in Guillain-Barré Syndrome: A Correlative Study.

Background and Aims: Guillain-Barré Syndrome (GBS), an immune-mediated neuropathy, is characterized by antibodies against gangliosides/ganglioside complexes (GSCs) of peripheral nerves. Antecedent infections have been reported to induce antibodies that cross-react with the host gangliosides and thereby have a pivotal role in conferring an increased risk for developing GBS. Data pertaining to the impact of various antecedent infections, particularly those prevalent in tropical countries like India on the ganglioside/GSC antibodies is sparse. We aimed at exploring the association between six antecedent infections and the profile of ganglioside/GSC antibodies in GBS. Methods: Patients with GBS (n = 150) and healthy controls (n = 50) were examined for the serum profile of antibodies against GM1, GM2, GD1a, GD1b, GT1b, and GQ1b and their GSCs by ELISA. These antibodies were correlated with immunoreactivities against Campylobacter jejuni, Japanese encephalitis (JE), dengue, influenza, zika, and chikungunya infections. Results: The frequencies of antibodies against six single gangliosides (P < 0.001) and their GSCs (P = 0.039) were significantly higher in patients as compared to controls. Except for GT1b-antibody which was more frequent in axonal GBS, none of the other ganglioside/GSC antibodies correlated with the electrophysiological subtypes of GBS. Antecedent JE infection was significantly associated with increased frequency of antibodies against GD1a, GD1b, GT1b, and GQ1b. Antibodies against GSCs were not influenced by the antecedent infections. Interpretation: This study for the first time shows an association between antecedent JE infection and ganglioside antibodies in GBS. This finding reinforces the determining role of antecedent infections on ganglioside antibody responses and the subsequent immunological processes in GBS.

Contact tracing of COVID-19 in Karnataka, India: Superspreading and determinants of infectiousness and symptomatic infection.

BACKGROUND: India has experienced the second largest outbreak of COVID-19 globally, yet there is a paucity of studies analysing contact tracing data in the region which can optimise public health interventions (PHI's). METHODS: We analysed contact tracing data from Karnataka, India between 9 March and 21 July 2020. We estimated metrics of transmission including the reproduction number (R), overdispersion (k), secondary attack rate (SAR), and serial interval. R and k were jointly estimated using a Bayesian Markov Chain Monte Carlo approach. We studied determinants of risk of further transmission and risk of being symptomatic using Poisson regression models. FINDINGS: Up to 21 July 2020, we found 111 index cases that crossed the super-spreading threshold of ≥8 secondary cases. Among 956 confirmed traced cases, 8.7% of index cases had 14.4% of contacts but caused 80% of all secondary cases. Among 16715 contacts, overall SAR was 3.6% [95% CI, 3.4-3.9] and symptomatic cases were more infectious than asymptomatic cases (SAR 7.7% vs 2.0%; aRR 3.63 [3.04-4.34]). As compared to infectors aged 19-44 years, children were less infectious (aRR 0.21 [0.07-0.66] for 0-5 years and 0.47 [0.32-0.68] for 6-18 years). Infectors who were confirmed ≥4 days after symptom onset were associated with higher infectiousness (aRR 3.01 [2.11-4.31]). As compared to asymptomatic cases, symptomatic cases were 8.16 [3.29-20.24] times more likely to cause symptomatic infection in their secondary cases. Serial interval had a mean of 5.4 [4.4-6.4] days, and case fatality rate was 2.5% [2.4-2.7] which increased with age. CONCLUSION: We found significant heterogeneity in the individual-level transmissibility of SARS-CoV-2 which could not be explained by the degree of heterogeneity in the underlying number of contacts. To strengthen contact tracing in over-dispersed outbreaks, testing and tracing delays should be minimised and retrospective contact tracing should be implemented. Targeted measures to reduce potential superspreading events should be implemented. Interventions aimed at children might have a relatively small impact on reducing transmission owing to their low symptomaticity and infectivity. We propose that symptomatic cases could cause a snowballing effect on clinical severity and infectiousness across transmission generations; further studies are needed to confirm this finding.

An algorithmic approach to identifying the aetiology of acute encephalitis syndrome in India: results of a 4-year enhanced surveillance study.

BACKGROUND: Annual outbreaks of acute encephalitis syndrome pose a major health burden in India. Although Japanese encephalitis virus (JEV) accounts for around 15% of reported cases, the aetiology of most cases remains unknown. We aimed to establish an enhanced surveillance network and to use a standardised diagnostic algorithm to conduct a systematic evaluation of acute encephalitis syndrome in India. METHODS: In this large-scale, systematic surveillance study in India, patients presenting with acute encephalitis syndrome (ie, acute onset of fever with altered mental status, seizure, or both) to any of the 18 participating hospitals across Uttar Pradesh, West Bengal, and Assam were evaluated for JEV (serum and cerebrospinal fluid [CSF] IgM ELISA) per standard of care. In enhanced surveillance, JEV IgM-negative specimens were additionally evaluated for scrub typhus, dengue virus, and West Nile virus by serum IgM ELISA, and for Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, dengue virus, herpes simplex virus, and enterovirus by CSF PCR across five referral laboratories. In 2017, chikungunya and Leptospira serum IgM by ELISA and Zika virus serum and CSF by PCR were also tested. FINDINGS: Of 10 107 patients with acute encephalitis syndrome enrolled in enhanced surveillance between Jan 1, 2014, and Dec 31, 2017, 5734 (57·8%) of 9917 participants with available data were male and 6179 (62·7%) of 9856 were children aged 15 years and younger. Among patients who provided a sample of either CSF or serum in enhanced surveillance, an aetiology was identified in 1921 (33·2%) of 5786 patients enrolled between 2014 and 2016 and in 1484 (34·3%) of 4321 patients enrolled in 2017. The most commonly identified aetiologies were JEV (1023 [17·7%] of 5786 patients), scrub typhus (645 [18·5%] of 3489), and dengue virus (161 [5·2%] of 3124). Among participants who provided both CSF and serum specimens, an aetiology was identified in 1446 (38·3%) of 3774 patients enrolled between 2014 and 2016 and in 936 (40·3%) of 2324 enrolled in 2017, representing a 3·1-times increase in the number of patients with acute encephalitis syndrome with an identified aetiology compared with standard care alone (299 [12·9%]; p<0·0001). INTERPRETATION: Implementation of a systematic diagnostic algorithm in an enhanced surveillance platform resulted in a 3·1-times increase in identification of the aetiology of acute encephalitis syndrome, besides JEV alone, and highlighted the importance of scrub typhus and dengue virus as important infectious aetiologies in India. These findings have prompted revision of the national testing guidelines for this syndrome across India. FUNDING: US Centers for Disease Control and Prevention.

HLA-B57 and gender influence the occurrence of tuberculosis in HIV infected people of south India.

BACKGROUND: Substantial evidence exists for HLA and other host genetic factors being determinants of susceptibility or resistance to infectious diseases. However, very little information is available on the role of host genetic factors in HIV-TB coinfection. Hence, a longitudinal study was undertaken to investigate HLA associations in a cohort of HIV seropositive individuals with and without TB in Bangalore, South India. METHODS: A cohort of 238 HIV seropositive subjects were typed for HLA-A, B, and DR by PCR-SSP and followed up for 5 years or till manifestation of Tuberculosis. HLA data of 682 HIV Negative healthy renal donors was used as control. RESULTS: The ratio of males and females in HIV cohort was comparable (50.4% and 49.6%). But the incidence of TB was markedly lower in females (12.6%,) than males (25.6%). Further, HLA-B*57 frequency in HIV cohort was significantly higher among females without TB (21.6%, 19/88) than males (1.7%, 1/59); P = 0.0046; OR = 38. CD4 counts also were higher among females in this cohort. CONCLUSION: This study suggests that HIV positive women with HLA-B*57 have less occurrence of TB as compared to males.

Mycophenolic acid inhibits replication of Japanese encephalitis virus.

BACKGROUND: Japanese encephalitis is a major public health problem in several parts of Asia, particularly India, Nepal, Sri Lanka and Myanmar (Burma). Despite its public health implications, there are no effective antiviral drugs available. METHODS: The present study evaluated the effect of mycophenolic acid on Japanese encephalitis virus (JEV) using an in vitro cytopathic effect inhibition assay, plaque reduction assay and virus yield reduction assay, and its therapeutic potential was also assessed in vivo in a mouse model. RESULTS: Analysis of the results obtained in the in vitro and in vivo experiments suggests that mycophenolic acid has significant antiviral activity against JEV, with an IC(50) of 3.1 µg/ml, a therapeutic index of 16 and a 75% protection against lethal challenge of JEV. CONCLUSION: The study concludes that this compound significantly inhibited the replication of JEV in vitro and protected mice in vivo.

Reduced T cell immunity in unmedicated, comorbidity-free obsessive-compulsive disorder: An immunophenotyping study.

BACKGROUND: Immune system aberrations have been postulated to play a role in the pathophysiology of Obsessive-compulsive disorder (OCD). This study was aimed to examine the profile of immune cell subsets in peripheral blood of un-medicated OCD patients. METHOD: Thirteen drug-naïve/free OCD patients and twenty-six age & sex matched healthy controls were recruited. Immunophenotyping was carried out by staining the whole blood specimens with fluorescent monoclonal antibodies against the cell surface markers such as CD45, CD3, CD16, CD56, CD8, CD4, CD28, CD25 and CD127, followed by data acquisition on BD FACSVerse™ flow cytometer. The proportions of CD4 and CD8 T cells; T regulatory (Tregs), Natural Killer (NK) cells and NK-T cells were compared between patients with OCD and healthy control subjects. RESULTS: Significantly reduced percentage of T regulatory (Treg) cells was observed in individuals with OCD compared to healthy control subjects [1.0 ± 0.7 vs. 1.9 ± 1.4; p = 0.03, r = 0.33]. CONCLUSION: Treg cells play a crucial role in regulating the immune response, especially by suppressing the functional activities of T cells. In this study, decreased population of Treg cells essentially indicates a dysregulated T cell and/or T cell mediated immune activation in drug-naïve OCD patients. This preliminary observation might form the basis of further studies examining the immuno-inflammatory/autoimmune origin of OCD.