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-1β, 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 transient mitochondrial functional impairment with acute heat exposure in children from Muzaffarpur region of Bihar, India

Over the past several years, the Muzaffarpur district of Bihar (India) has witnessed recurrent outbreaks of acute encephalitis illness of unknown etiology, called acute encephalitis syndrome (AES) among young children, especially during the peak-summer season. Pesticide exposure, viral encephalitis, and litchi toxin intake have all been postulated as potential sources of the ailment. However, no conclusive etiology for AES has been identified in the affected children. During recent rounds of the outbreak, metabolic abnormalities have been documented in these children, and a direct correlation was observed between higher environmental temperature during the peak-summer month and AES caseload. The clinical and metabolic profiles of these children suggested the possible involvement of mitochondrial dysfunction during heat stress as one of the several contributory factors leading to multisystem metabolic derangement. The present study observed that mitochondrial function parameters such as cell death, mitochondrial membrane potential, oxidative stress, and mitochondrial pathway-related gene expression in peripheral blood mononuclear cells (PBMCs) isolated from children were affected in peak-summer when compared to post-summer months. Similar observations of mitochondrial function parameters along with impaired bioenergetic parameters were demonstrated in the heat-exposed model of PBMCs isolated from healthy adult individuals. In conclusion, the results suggested that there is an association of transient mitochondrial dysfunction when exposed to sustained heat during the summer months. One may consider mitochondrial dysfunction as one of the important factors leading to an outbreak of AES among the children from affected regions though this needs to be substantiated with further studies.

Infectious Causes of Acute Encephalitis Syndrome in India - Decadal Change and the Way Forward

The diagnosis and management of encephalitis were previously largely based on clinical grounds and minimal laboratory investigations. Japanese encephalitis (JE) gets considered as the probable diagnosis in most encephalitis cases. However, reports of JE in adults and the elderly are increasing after the JE vaccine introduction among children in 2006. The Nipah virus (NiV) emerged in 2002 and continues to afflict humans in new geographic areas. Many other infections cause encephalitis, including Chandipura, chikungunya, dengue, and West Nile. Significant advances in diagnostic testing like multiplex testing panels and metagenomic approaches along with sequencing have helped in the detection of new etiologies. Recent years have witnessed an increase in climate-sensitive zoonotic diseases with encephalitis. This highlights the importance of the One Health approach in studying the impact of climate change-associated infectious diseases on human health. The government of India's efforts to develop health research infrastructure would help future responses to emerging infectious disease epidemics.

Molecular detection of spotted fever group of Rickettsiae in acute encephalitis syndrome cases from eastern Uttar Pradesh region of India

The Eastern Uttar Pradesh region of India is known for its endemicity of acute encephalitis syndrome (AES). Decades of research have established that Orientia tsutsugamushi, a causative of scrub typhus, is a substantial contributor (>60%) for the AES cases besides other aetiology, but additional factors in the remaining proportion are still unidentified. Rickettsial infections are challenging to diagnose in clinical settings due to overlapping clinical symptoms, the absence of definitive indicators, a low index of suspicion, and the lack of low-cost, rapid diagnostic tools. Hence, the present study was designed to determine the load of rickettsial infections among AES cases. Furthermore, we aim to find out the prevalent rickettsial species in AES cases as well as in the vector population at this location. The study included the whole blood/cerebrospinal fluid of AES patients and arthropod specimens from rodents. The molecular identification was performed using the 23S-5S intergenic spacer region and ompB gene with genomic DNA obtained from studied specimens. We detected 5.34% (62/1160) of rickettsial infection in AES cases. Among these, phylogenetic analysis confirmed the presence of 54.8% Rickettsia conorii (n = 34) and 16.1% of Rickettsia felis (n = 10), while the rest proportion of the isolates was unidentified at the species level. Furthermore, R. felis was identified in one CSF sample from AES patients and three flea samples from Xenopsylla cheopis. Rickettsia spp. was also confirmed in one Ornithonyssus bacoti mite sample. The results of this investigation concluded the presence of spotted fever group Rickettsia spp. among AES identified cases as well as in the mite and flea vectors that infest rodents.

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.

The Outbreaks of Acute Encephalitis Syndrome in Uttar Pradesh, India (1978–2020) and Its Effective Management: A Remarkable Public Health Success Story

Introduction

Acute encephalitis syndrome (AES) is a major public health enigma in India and the world. Uttar Pradesh (UP) is witnessing recurrent and extensive seasonal AES outbreaks since 1978. Government of India and UP state government have devised various mitigation measures to reduce AES burden and AES associated mortality, morbidity and disability in Uttar Pradesh. The aim of this study was to describe the public health measures taken in order to control seasonal outbreaks of AES in UP between 1978 and 2020.

Methods

We used literature review as a method of analysis, including the Indian government policy documents. This review utilized search engines such as PubMed, Google Scholar, Research Gate, Cochrane, Medline to retrieve articles and information using strategic keywords related to Acute Encephalitis Syndrome. Data was also collected from progress reports of government schemes and websites of Indian Council of Medical Research (ICMR), National Vector Borne Disease Control Programme (NVBDCP) and Integrated Disease Surveillance Programmes (IDSP).

Results

The incidence of AES cases in UP have declined from 18.2 per million population during 2005-2009 to 15 per million population during 2015-2019 [CI 12.6–20.6, P-value < 0.001] and case fatality rate (CFR) reduced from 33% during 1980-1984 to 12.6% during 2015-2019 [CI 17.4–30.98, P-value < 0.001]. AES incidence was 9 (2019) and 7 (2020) cases per million populations respectively and CFR was 5.8% (2019) and 5% (2020). This decline was likely due to active surveillance programs identifying aetiological agents and risk factors of AES cases. The identified etiologies of AES include Japanese encephalitis virus (5–20%), Enterovirus (0.1–33%), Orientia tsutsugamushi (45–60%) and other viral (0.2–4.2%), bacterial (0–5%) and Rickettsial (0.5–2%) causes. The aggressive immunization programs against Japanese encephalitis with vaccination coverage of 72.3% in UP helped in declining of JE cases in the region. The presumptive treatment of febrile cases with empirical Doxycycline and Azithromycin (EDA) caused decline in Scrub Typhus-AES cases. Decrease in incidence of vector borne diseases (Malaria, Dengue, Japanese Encephalitis and Kala Azar) i.e., 39.6/100,000 population in 2010 to 18/100,000 population in 2017 is highlighting the impact of vector control interventions. Strengthening healthcare infrastructure in BRD medical college and establishment of Encephalitis Treatment Centre (ETC) at peripheral health centres and emergency ambulance services (Dial 108) reduced the referral time and helped in early treatment and management of AES cases. The AES admissions increased at ETC centres to 60% and overall case fatality rate of AES declined to 3%. Under clean India mission and Jal Jeevan mission, proportion of population with clean drinking water increased from 74.3% in 1992 to 98.7% in 2020. The proportion of household having toilet facilities increased from 22.9% in 1992 to 67.4% in 2020. Provisions for better nutritional status under state and national nutrition mission helped in reducing the burden of stunting (52%) and wasting (53.4%) among under five children in 1992 to 38.8% (stunting) and 36.8% (wasting) in year 2018. These factors have all likely contributed to steady AES decline observed in UP.

Conclusion

There is a recent steady decline in AES incidence and CFR since implementation of intensive AES surveillance system and JE immunization campaigns which is highlighting the success of interventions made by central and state government to control seasonal AES outbreaks in UP. Currently, AES incidence is 9 cases per million population (in year 2019) and mortality is 5.8%.

Pathogenic Variants in NUP214 Cause "Plugged" Nuclear Pore Channels and Acute Febrile Encephalopathy

We report biallelic missense and frameshift pathogenic variants in the gene encoding human nucleoporin NUP214 causing acute febrile encephalopathy. Clinical symptoms include neurodevelopmental regression, seizures, myoclonic jerks, progressive microcephaly, and cerebellar atrophy. NUP214 and NUP88 protein levels were reduced in primary skin fibroblasts derived from affected individuals, while the total number and density of nuclear pore complexes remained normal. Nuclear transport assays exhibited defects in the classical protein import and mRNA export pathways in affected cells. Direct surface imaging of fibroblast nuclei by scanning electron microscopy revealed a large increase in the presence of central particles (known as "plugs") in the nuclear pore channels of affected cells. This observation suggests that large transport cargoes may be delayed in passage through the nuclear pore channel, affecting its selective barrier function. Exposure of fibroblasts from affected individuals to heat shock resulted in a marked delay in their stress response, followed by a surge in apoptotic cell death. This suggests a mechanistic link between decreased cell survival in cell culture and severe fever-induced brain damage in affected individuals. Our study provides evidence by direct imaging at the single nuclear pore level of functional changes linked to a human disease.

Profile of Pediatric Scrub Typhus in Odisha, India

OBJECTIVE

To investigate the distribution and clinical profile of scrub typhus infection among children with acute febrile illness in Odisha.

METHODS

Children (<15 y) presenting with acute fever (>5 days) in 4 agro-climatic zones from June to November 2017 were evaluated. Patients were screened for malaria, leptospira, dengue, typhoid and scrub typhus. Scrub typhus was confirmed by IgM ELISA and PCR.

RESULTS

Out of 413 cases examined, 48.7% were positive for scrub typhus, and 5.5% of them developed systemic complications. Eschar was found in 17.9% of cases. Five days treatment of Doxycycline and/or Azithromycin was clinically effective against scrub typhus.

CONCLUSIONS

Our study highlights that scrub typhus is one of the causes of high morbidity in children during rainy months in Odisha.

Hypoglycemic Toxins and Enteroviruses as Causes of Outbreaks of Acute Encephalitis-Like Syndrome in Children, Bac Giang Province, Northern Vietnam

We investigated the cause of seasonal outbreaks of pediatric acute encephalitis-like syndrome associated with litchi harvests (May–July) in northern Vietnam since 2008. Nineteen cerebrospinal fluid samples were positive for human enterovirus B, and 8 blood samples were positive for hypoglycemic toxins present in litchi fruits. Patients who were positive for hypoglycemic toxins had shorter median times between disease onset and admission, more reports of seizures, more reports of hypoglycemia (glucose level <3 mmol/L), lower median numbers of leukocytes in cerebrospinal fluid, and higher median serum levels of alanine aminotransferase and aspartate transaminase than did patients who were positive for enteroviruses. We suggest that children with rapidly progressing acute encephalitis-like syndrome at the time of the litchi harvest have intoxication caused by hypoglycemic toxins, rather than viral encephalitis, as previously suspected. These children should be urgently treated for life-threatening hypoglycemia.

Scrub Typhus as a Cause of Acute Encephalitis Syndrome, Gorakhpur, Uttar Pradesh, India

Outbreaks of acute encephalitis syndrome (AES) have been occurring in Gorakhpur Division, Uttar Pradesh, India, for several years. In 2016, we conducted a case-control study. Our findings revealed a high proportion of AES cases with Orientia tsutsugamushi IgM and IgG, indicating that scrub typhus is a cause of AES.

Paediatric Active Enhanced Disease Surveillance (PAEDS) annual report 2015: Prospective hospital-based surveillance for serious paediatric conditions

INTRODUCTION

The Paediatric Active Enhanced Disease Surveillance (PAEDS) network is a hospital-based active surveillance system employing prospective case ascertainment for selected serious childhood conditions, particularly vaccine preventable diseases and potential adverse events following immunisation (AEFI). PAEDS data is used to better understand these conditions, inform policy and practice under the National Immunisation Program, and enable rapid public health responses for certain conditions of public health importance. PAEDS enhances data available from other Australian surveillance systems by providing prospective, detailed clinical and laboratory information on children with selected conditions. This is the second of the planned annual PAEDS reporting series, and presents surveillance data for 2015.

METHODS

Specialist surveillance nurses screened hospital admissions, emergency department records, laboratory and other data, on a daily basis in 5 paediatric tertiary referral hospitals in New South Wales, Victoria, South Australia, Western Australia and Queensland to identify children with the selected conditions. Standardised protocols and case definitions were used across all sites. Conditions under surveillance in 2015 included acute flaccid paralysis (a syndrome associated with poliovirus infection), acute childhood encephalitis (ACE), influenza, intussusception (IS; a potential AEFI with rotavirus vaccines), pertussis and varicella-zoster virus infection (varicella and herpes zoster). Most protocols restrict eligibility to hospitalisations, ED only presentations are also included for some conditions.

METHODS

: In 2015, there were 674 cases identified across all conditions under surveillance. Key outcomes of PAEDS included: contribution to national AFP surveillance to reach WHO reporting targets; identification of signals for Mycoplasma pneumoniae and parechovirus-related outbreaks (ACE surveillance); and demonstration of high influenza activity with vaccine effectiveness (VE) analysis supportive of vaccination. Surveillance for IS remains ongoing with any identified AEFIs reported to the relevant State Health Department; varicella and herpes zoster case numbers decreased slightly from previous years in older children not eligible for catch-up. Pertussis case numbers increased in early 2015 and analysis of cases in children aged <1 year demonstrated the importance of timely childhood and maternal immunisation.

CONCLUSIONS

PAEDS continues to provide unique policy-relevant data on serious paediatric conditions using hospital-based sentinel surveillance.

Scrub Typhus Leading to Acute Encephalitis Syndrome, Assam, India

To determine the contribution of Orientia tsutsugamushi, the agent of scrub typhus, as a cause of acute encephalitis syndrome (AES) in Assam, India, we conducted a retrospective study of hospital patients with symptoms of AES during 2013–2015. Our findings suggest that O. tsutsugamushi infection leads to AES and the resulting illness and death.