Influence of environmental factors on tick diversity and abundance in different animal resting habitats in forest areas of the south Western Ghats.

Most tick-borne disease causing pathogens originate in wildlife and are zoonotic in nature. A key to protecting human and animal health is to understand the biology and ecology of tick establishment. The tick distribution in wild animal habitats has been attributed to multiple environmental factors, and the studies on this topic are limited. Therefore, the objective of the study is to understand the influence of environmental factors on tick diversity and abundance in wild animal resting habitats. The study was carried out in 21 different animal resting habitats in the forest areas of Wayanad district, and they were divided into three groups based on the presence or absence of selected environmental parameters. A total of 10,849 ticks with 12 species belonging to five genera were collected. Regardless of the type of habitats, Haemaphysalis spinigera (59.52%) and Haemaphysalis turturis (33.20%) were the dominant species. Tick abundance showed greater variability between types of habitats ranging from 1.23 to 28.5. The greatest diversity and abundance were found in the group one. The group 3 had greater diversity and less abundance than the group 2. Both Simpson's diversity index and Shannon's diversity index were high for groups 2. Substantial variation in diversity and abundance of ticks occurred in different groups based on different environmental factors. The dominance of ticks of the genus Haemaphysalis a primary vector of Kyasanur Forest Disease highlights the need to carry out various control strategies to reduce the tick population.

Sofosbuvir and its tri-phosphate metabolite inhibit the RNA-dependent RNA polymerase activity of non-structural protein 5 from the Kyasanur forest disease virus.

Kyasanur forest disease is a neglected zoonotic disease caused by a single-stranded RNA-based flavivirus, the incidence of which was first recorded in 1957 in the Southern part of India. Kyasanur forest disease virus is transmitted to monkeys and humans through the infected tick bite of Haemophysalis spinigera. Kyasanur forest disease is a febrile illness, which in severe cases, results in neurological complications leading to mortality. The current treatment regimens are symptomatic and supportive, and no targeted therapies are available for this disease. In this study, we evaluated the ability of FDA-approved drugs sofosbuvir (and its active metabolite) and Dasabuvir to inhibit the RNA-dependent RNA polymerase activity of NS5 protein from the Kyasanur forest disease virus. NS5 protein containing the N-terminal methyl transferase domain and C-terminal RNA-dependent RNA polymerase domain was expressed in Escherichia coli, and RNA-dependent RNA polymerase activity was demonstrated with the purified protein. The RNA-dependent RNA polymerase assay conditions were optimized, followed by the determination of apparent Km,ATP to validate the enzyme preparation. Half maximal-inhibitory concentrations against RNA-dependent RNA polymerase activity were determined for Sofosbuvir and its active metabolite. Dasabuvir did not show detectable inhibition with the tested conditions. This is the first demonstration of the inhibition of RNA-dependent RNA polymerase activity of NS5 protein from the Kyasanur forest disease virus with small molecule inhibitors. These initial findings can potentially facilitate the discovery and development of targeted therapies for treating Kyasanur forest disease.

Kyasanur forest disease and climatic attributes in India.

BACKGROUND & OBJECTIVES: In India, Kyasanur Forest Disease has been reported from the states of Karnataka, Kerala, Goa, and Maharashtra. The relationship between climatic factors and transmission of KFD remains untouched, therefore, the present study was undertaken. METHODS: Based on the occurrence of cases, Shivamogga district (Karnataka) and Wayanad district in Kerala and northern Goa (Goa state) were selected for the study. Data on the incidence of KFD and climate factors were collected from concerned authorities. To determine the relationship between dependent and independent variables, spearman's correlation was calculated for monthly as well as with lag months. RESULTS: KFD cases and temperature (°C) were found significantly correlated up to 1 months' lag period (p<0.05) while with precipitation relationship was found negatively significant for 0-3 months' lag. The range of suitable temperature for KFD in Shivamogga, Goa and Wayanad was found as 20-31°C, 25-29°C and 27-31°C respectively. The cumulative precipitation during transmission months (November-May) ranged from <150-500mm, while in non-transmission months (June-October) from >1100-2400mm. INTERPRETATION & CONCLUSION: The analysis of three sites revealed that with the increase in temperature, the intensity of KFD transmission decreases as corroborated by the seasonal fluctuations in Shivamogga, Goa and Wayanad. High precipitation from June to October rovides suitable ecology to tick vector and sets in transmission season from November to May when cumulative precipitation is <500 mm.

Retrospective Study of Kyasanur Forest Disease and Deaths among Nonhuman Primates, India, 1957-2020.

Kyasanur Forest disease (KFD) is a tickborne hemorrhagic disease affecting primates along the Western Ghats mountain range in India. Our retrospective study indicated that >3,314 monkey deaths attributed to KFD were reported in KFD-endemic states in India during 1957-2020. These data can help guide surveillance to protect animal and human health.

Identification of bio-climatic determinants and potential risk areas for Kyasanur forest disease in Southern India using MaxEnt modelling approach.

BACKGROUND: Kyasanur forest disease (KFD), known as monkey fever, was for the first time reported in 1957 from the Shivamogga district of Karnataka. But since 2011, it has been spreading to the neighbouring state of Kerala, Goa, Maharashtra, and Tamil Nadu. The disease is transmitted to humans, monkeys and by the infected bite of ticks Haemaphysalis spinigera. It is known that deforestation and ecological changes are the main reasons for KFD emergence, but the bio-climatic understanding and emerging pathways remain unknown. METHODS: The present study aims to understand the bio-climatic determinants of distribution of tick vector of KFD in southern India using the Maximum Entropy (MaxEnt) model. The analysis was done using 34 locations of Haemaphysalis spinigera occurrence and nineteen bio-climatic variables from WorldClim. Climatic variables contribution was assessed using the Jackknife test and mean AUC 0.859, indicating the model performs with very high accuracy. RESULTS: Most influential variables affecting the spatial distribution of Haemaphysalis spinigera were the average temperature of the warmest quarter (bio10, contributed 32.5%), average diurnal temperature range (bio2, contributed 21%), precipitation of wettest period (bio13, contributed 17.6%), and annual precipitation (bio12, contributed 11.1%). The highest probability of Haemaphysalis spinigera presence was found when the mean warmest quarter temperature ranged between 25.4 and 30 °C. The risk of availability of the tick increased noticeably when the mean diurnal temperature ranged between 8 and 10 °C. The tick also preferred habitat having an annual mean temperature (bio1) between 23 and 26.2 °C, mean temperature of the driest quarter (bio9) between 20 and 28 °C, and mean temperature of the wettest quarter (bio8) between 22.5 and 25 °C. CONCLUSIONS: The results have established the relationship between bioclimatic variables and KFD tick distribution and mapped the potential areas for KFD in adjacent areas wherein surveillance for the disease is warranted for early preparedness before the occurrence of outbreaks etc. The modelling approach helps link bio-climatic variables with the present and predicted distribution of Haemaphysalis spinigera tick.

The species distribution of ticks & the prevalence of Kyasanur forest disease virus in questing nymphal ticks from Western Ghats of Kerala, South India.

Background & objectives: Kyasanur forest disease (KFD) is a zoonotic tick-borne disease across the Western Ghats of India. With the discovery of a cluster of human KFD cases in the Wayanad district of Kerala, the present study was focused on detecting KFD virus (KFDV) in tick populations. To manage this disease, it is necessary to understand the diversity of the tick species and factors influencing the distribution, abundance and prevalence of infected ticks in Wayanad district. Methods: Surveys were conducted from November 2016 to May 2018 in four forest ranges of Wayanad district. Ticks were collected by the dragging method and were identified to species level and assayed for virus detection using real-time polymerase chain reaction. Results: A total of 25,169 ticks were collected from 64 sites. Of the identified species, Haemaphysalis spinigera was the most abundant (56.64%), followed by H. turturis 9047 (35.94%), H. bispinosa 999 (3.96%), Amblyomma integrum 691 (2.74%), H. kyasanurensis (0.55%), Rhipicephalus sanguineus (0.08%), Hyalomma marginatum (0.02%), H. cuspidata (0.01%), R.microplus (0.01%) and Dermacentor auratus (0.003%). The nymphal stage was predominant from December to February having peak activity in January. A total of 572 pools were screened for the presence of KFDV, of which 21 pools were positive. The infection rates in H. spinigera and H. turturis tick were 2.62 and 1.04 per cent, respectively. Interpretation & conclusions: The circulation of KFDV was detected and its correlation with the prevalence in ticks near the fragmented forest and teak plantation areas of Wayanad district. Residents and visitors of these regions may become vulnerable to tick bites and to an increased risk of KFD as the distribution of established, infected tick populations continues to expand.

Experiences of Indian Council of Medical Research with tick-borne zoonotic infections: Kyasanur Forest disease & Crimean-Congo haemorrhagic fever in India with One Health focus.

Emergence and re-emergence of several pathogens have been witnessed by this century in the form of outbreaks, epidemics and pandemics. In India, the influencing factor that promotes dissemination of emerging and re-emerging viral infections is the biogeographical zones: a megadiverse country, characterized by varied geographical, climatic conditions and ever-changing socio-economical and geopolitical issues. These influence the movement of humans and animals and add layers of complexity for the identification and timely management of infectious diseases. This review focuses on two tick-borne infections: Crimean-Congo haemorrhagic fever (CCHF) and Kyasanur forest disease (KFD). In the last two decades, these viruses have emerged and caused outbreaks in different parts of India. KFD virus was initially identified in 1957 and was known to be endemic in Karnataka State while CCHF virus was first identified during 2010 in Gujarat State, India. These viruses have managed to emerge in new areas within the last decade. With changing epidemiology of these arboviruses, there is a probability of the emergence of these viruses from new areas in future. The investigations on these two diseases under the One Health focus involved early detection, quickly developing diagnostic tools, identifying stakeholders, capacity building by developing collaboration with major stakeholders to understand the epidemiology and geographical spread in domestic animal reservoirs and tick vectors in the affected areas, developing laboratory network, providing diagnostic reagents and biosafety and laboratory diagnosis training to the network laboratories to control these diseases.

Geographic distribution of Tick-borne encephalitis virus complex.

A comprehensive understanding of the geographic distribution of the tick-borne encephalitis virus (TBEV) complex is necessary due to increasing transboundary movement and cross-reactivity of serological tests. This review was conducted to identify the geographic distribution of the TBEV complex, including TBE virus, Alkhurma haemorrhagic fever virus, Kyasanur forest disease virus, louping-ill virus, Omsk haemorrhagic fever virus, and Powassan virus. Published reports were identified using PubMed, EMBASE, and the Cochrane library. In addition to TBEV complex case-related studies, seroprevalence studies were also retrieved to assess the risk of TBEV complex infection. Among 1406 search results, 314 articles met the inclusion criteria. The following countries, which are known to TBEV epidemic region, had conducted national surveillance studies: Austria, China, Czech, Denmark, Estonia, Finland, Germany, Hungary, Italy, Latvia, Norway, Poland, Romania, Russia, Switzerland, Sweden, Slovenia, and Slovakia. There were also studies/reports on human TBEV infection from Belarus, Bulgaria, Croatia, France, Japan, Kyrgyzstan, Netherland, and Turkey. Seroprevalence studies were found in some areas far from the TBEV belt, specifically Malaysia, Comoros, Djibouti, and Kenya. Kyasanur forest disease virus was reported in southwestern India and Yunnan of China, the Powassan virus in the United States, Canada, and east Siberia, Alkhurma haemorrhagic fever virus in Saudi Arabia and east Egypt, and Louping-ill virus in the United Kingdom, Ireland, and east Siberia. In some areas, the distribution of the TBEV complex overlaps with that of other viruses, and caution is recommended during serologic diagnosis. The geographic distribution of the TBEV complex appears to be wide and overlap of the TBE virus complex with other viruses was observed in some areas. Knowledge of the geographical distribution of the TBEV complex could help avoid cross-reactivity during the serologic diagnosis of these viruses. Surveillance studies can implement effective control measures according to the distribution pattern of these viruses.

Kinetics of viral RNA, immunoglobulin-M & G antibodies in Kyasanur forest disease.

Background & objectives: Kyasanur forest disease (KFD) is an infectious disease discovered in Karnataka State of India in 1957; since then, the State has been known to be enzootic for KFD. In the last few years, its presence was observed in the adjoining five States of the Western Ghats of India. The present study was conducted to understand the kinetics of viral RNA, immunoglobulin M (IgM) and IgG antibody in KFD-infected humans for developing a diagnostic algorithm for KFD. Methods: A prospective follow up study was performed among KFD patients in Sindhudurg district of Maharashtra State, India. A total of 1046 suspected patients were tested, and 72 KFD patients were enrolled and followed for 17 months (January 2016 to May 2017). Serum samples of KFD patients were screened for viral RNA, and IgM and IgG antibodies. Results: KFD viral positivity was observed from 1st to 18th post-onset day (POD). Positivity of anti-KFD virus (KFDV) IgM antibodies was detected from 4th till 122nd POD and anti-KFDV IgG antibodies detected from 5th till 474th POD. A prediction probability was determined from statistical analysis using the generalized additive model in R-software to support the laboratory findings regarding viral kinetics. Interpretation & conclusions: This study demonstrated the presence of KFD viral RNA till 18th POD, IgM antibodies till 122nd POD and IgG till the last sample collected. Based on our study an algorithm was recommended for accurate laboratory diagnosis of KFDV infection. A sample collected between 1 and 3 POD can be tested using KFDV real-time reverse transcriptase polymerase chain reaction (RT-PCR); between 4 and 24 POD, the combination of real-time RT-PCR and anti-KFDV IgM enzyme-linked immunosorbent assay (ELISA) tests can be used; between POD 25 and 132, anti-KFDV IgM and IgG ELISA are recommended.

Assessment of NS1 protein as an early diagnostic marker for Kyasanur forest disease virus.

BACKGROUND & OBJECTIVES: Due to the emergence of Kyasanur forest disease (KFD) virus to new regions in India, there is an urgent need to develop an early diagnostic system, which is cost-effective and can be efficiently used with minimum paraphernalia. The non-structural-1 (NS1) protein is known to be an early diagnostic marker for flaviviruses. Furthermore, NS1 antigen capture ELISA kits developed using bacterially expressed dengue NS1 protein are commercially available. METHODS: Based on the data available on dengue virus, West Nile virus and other flaviviruses, bacterially expressed Kyasanur forest disease virus (KFDV) NS1 protein and polyclonal serum raised against the NS1 protein in mice and rabbit were used to develop an antigen capture ELISA for early diagnosis of the virus. The feasibility of this ELISA was further tested using in silico predictions. RESULTS: KFDV NS1 gene was cloned, expressed and confirmed by SDS-PAGE and western blotting. An antigen detection ELISA was standardized and sensitivity and specificity was tested with other flaviviruses. KFDV acute phase 43 samples were tested and only two were found to be positive for KFDV NS1 antigen. Superimposition of KFDV NS1 and TBEV NS1 revealed a root mean square distance (RMSD) of ~0.79 Å covering 1220 backbone atoms. This implies that the structures are very similar in terms of 3D fold. The identity of amino acid composition between these proteins was 73.4% and similarity was 92.9%, as revealed from the pairwise comparison. INTERPRETATION & CONCLUSION: The study points out that the half-life, expression and secretion levels of KFDV NS1 protein are not sufficient enough for its use as early diagnostic marker. The protein may have to be expressed in eukaryotic host to counter the lack of glycosylation in bacterial plasmid based expression of proteins. Hence, bacterially expressed KFDV NS1 protein may not be an ideal early diagnostic marker for the virus.

Alkhurma Hemorrhagic Fever Virus RNA in Hyalomma rufipes Ticks Infesting Migratory Birds, Europe and Asia Minor.

Alkhurma hemorrhagic fever virus RNA was detected in immature Hyalomma rufipes ticks infesting northward migratory birds caught in the North Mediterranean Basin. This finding suggests a role for birds in the ecology of the Alkhurma hemorrhagic fever virus and a potential mechanism for dissemination to novel regions. Increased surveillance is warranted.

Clinical & epidemiological significance of Kyasanur forest disease.

Kyasanur forest disease (KFD) is a known viral haemorrhagic fever in India, for the last 60 years. However, in recent years, the change in epidemiological profile of the disease has suggested that it is now time to consider KFD as an emerging tropical disease in India. The preference should be to educate not only the villagers where it is being reported or detected but also to public health experts, veterinarians, forest officials and medical professionals to pay attention while seeing a patient overlapping with endemic diseases such as Japanese encephalitis, West Nile, dengue, chikungunya, malaria and tuberculosis. Although the existence of KFD is known for a long time, updated understanding of its clinical profile in humans is still limited. This article describes in detail the clinical presentation of KFD reported till date. It also highlights geographical distribution of the disease, risk factors for virus transmission, biochemical/haematological findings and control measures. There is an urgent need for research on KFD, particularly for understanding biphasic nature of illness, development of cost-effective diagnostic tools, utility of non-invasive samples for diagnosis and development of new vaccines.

Bioinformatics characterization of envelope glycoprotein from Kyasanur Forest disease virus.

BACKGROUND & OBJECTIVES: Kyasanur Forest disease (KFD) is a febrile illness characterized by haemorrhages and caused by KFD virus (KFDV), which belongs to the Flaviviridae family. It is reported to be an endemic disease in Shimoga district of Karnataka State, India, especially in forested and adjoining areas. Several outbreaks have been reported in newer areas, which raised queries regarding the changing nature of structural proteins if any. The objective of the study was to investigate amino acid composition and antigenic variability if any, among the envelope glycoprotein (E-proteins) from old and new strains of KFDV. METHODS: Bioinformatic tools and techniques were used to predict B-cell epitopes and three-dimensional structures and to compare envelope glycoprotein (E-proteins) between the old strains of KFDV and those from emerging outbreaks till 2015. RESULTS: The strain from recent outbreak in Thirthahalli, Karnataka State (2014), was similar to the older strain of KFDV (99.2%). Although mutations existed in strains from 2015 in Kerala KFD sequences, these did not alter the epitopes. INTERPRETATION & CONCLUSIONS: The study revealed that though mutations existed, there were no drastic changes in the structure or antigenicity of the E-proteins from recent outbreaks. Hence, no correlation could be established between the mutations and detection in new geographical areas. It seems that KFDV must be present earlier also in many States and due to availability of testing system and alertness coming into notice now.

Prevalence and spatial distribution of Ixodid tick populations in the forest fringes of Western Ghats reported with human cases of Kyasanur forest disease and monkey deaths in South India.

Kyasanur forest disease (KFD) is a major tick-borne viral haemorrhagic fever caused by KFD virus (KFDV) (Flaviviridae). The disease was reported to be confined to five districts of Karnataka state India until 2011. During 2012-2016, emergence of KFD has been reported in newer areas of Karnataka and adjoining states. Therefore, survey of tick vectors was carried out in these new areas of Karnataka and adjoining states reported with monkey deaths and human cases of KFD. In all selected sites, ticks from the forest floor were collected by lint clothes using flagging method. Tick samples were tested for KFDV nucleic acid by real-time RT-PCR. A total of 4772 ticks, comprising eight species of genus Haemaphysalis and one species each of genus Amblyomma, Ixodes and Rhipicephalus was collected. Haemaphysalis spinigera, the principal vector of KFDV was the predominant tick species (59.5%) collected followed by H. turturis (8.6%). The abundance of H. spinigera ranged from 9.2 to 33.9 per man-hour in the six districts surveyed. Of 214 (4418 tick samples) pools screened by real-time RT-PCR, two pools of H. spinigera were positive for KFDV. High abundance of Haemaphysalis vectors in the six districts indicated that the districts are receptive for KFD outbreaks. KFDV was detected in the tick vectors in the new foci of the KFD. Data on tick distribution will be useful in creating KFD risk map for strengthening the ongoing preventive measures such as vaccination and supply of insect repellents to the high risk groups and intensive health education.

Kyasanur Forest disease virus NS3 helicase: Insights into structure, activity, and inhibitors.

Kyasanur Forest disease virus (KFDV), a tick-borne flavivirus prevalent in India, presents a serious threat to human health. KFDV NS3 helicase (NS3hel) is considered a potential drug target due to its involvement in the viral replication complex. Here, we resolved the crystal structures of KFDV NS3hel apo and its complex with three phosphate molecules, which indicates a conformational switch during ATP hydrolysis. Our data revealed that KFDV NS3hel has a higher binding affinity for dsRNA, and its intrinsic ATPase activity was enhanced by dsRNA while being inhibited by DNA. Through mutagenesis analysis, several residues within motifs I, Ia, III, V, and VI were identified to be crucial for NS3hel ATPase activity. Notably, the M419A mutation drastically reduced NS3hel ATPase activity. We propose that the methionine-aromatic interaction between residues M419 and W294, located on the surface of the RNA-binding channel, could be a target for the design of efficient inhibitor probes. Moreover, epigallocatechin gallate (EGCG), a tea-derived polyphenol, strongly inhibited NS3hel ATPase activity with an IC50 value of 0.8 µM. Our computational docking data show that EGCG binds at the predicted druggable hotspots of NS3hel. Overall, these findings contribute to the development and design of more effective and specific inhibitors.

Development of a clinical scoring system to make a presumptive diagnosis of Kyasanur Forest Disease: a case-control study from South India.

Introduction: Kyasanur Forest Disease (KFD) is a viral haemorrhagic fever endemic in South India. Based on clinical presentation alone, it is challenging to distinguish KFD from other febrile illnesses in the region. The study aimed to develop a clinical scoring system for early presumptive diagnosis of KFD. Patients and methods: This retrospective case-control study included microbiologically diagnosed KFD patients (n=186) with other undifferentiated febrile illnesses as controls (n=203). The clinical and laboratory features between cases and controls were compared. A logistic regression analysis included those variables found to be significantly associated with KFD on univariate analysis. The adjusted odds ratio for the significant variables was calculated and converted into logarithmic scales. These numbers were rounded off to the nearest integer to find the score assigned to each variable. A receiver operating characteristics curve was created to find the best cut-off for the scoring system that predicted the diagnosis of KFD. Results: A total of 186 anonymised cases and 203 anonymised controls were recruited from the records for this study. Myalgia, headache, lymphadenopathy, bleeding manifestations, Central Nervous System (CNS) involvement, raised haematocrit, leukopenia, and raised transaminases were more common in patients with KFD. Except for lymphadenopathy and raised transaminases, all the other variables were independent predictors of making a diagnosis of KFD. Since raised transaminases tended towards significance, it was included in the scoring system with other independent predictors. A scoring system was created with a maximum score of 12. The receiver operating characteristic curve showed an Area Under Curve of 0.912 (95%CI: 0.88-0.94). A score of 4 or more was found to have a sensitivity and specificity of 83% and 87%, respectively. Conclusion: The presence of specific features should alert primary care physicians working in endemic areas about the possibility of KFD. This diagnostic scoring system can be used to make a presumptive diagnosis of KFD after undergoing a prospective validation study.

Clinical, epidemiological, and molecular investigation of Kyasanur forest disease from Karnataka state, India during 2018-2019.

BACKGROUND: In this study, we carried out an investigation of Kyasanur Forest Disease (KFD) suspected human cases reported in Karnataka state, India from December 2018 to June 2019. METHODS: The clinical samples of KFD suspected cases (n = 1955) from 14 districts of Karnataka were tested for KFD using real-time RT-PCR and IgM ELISA. Further, the KFD-negative samples were tested for IgM antibodies against dengue and chikungunya viruses. Monkey samples (n = 276) and tick pools (n = 11582) were also screened using real-time RT-PCR. KFD-positive samples were further analysed using next-generation sequencing along with clinico-epidemiological analysis. RESULTS: Of all, 173 (8.8%) cases tested positive for KFD either by real-time RT-PCR (n = 124), IgM ELISA (n = 53) or both tests (n = 4) from seven districts. Among KFD-negative cases, IgM antibody positivity was observed for dengue (2.6%), chikungunya (5.8%), dengue and chikungunya coinfection (3.7%). KFD cases peaked in January 2019 with fever, conjunctivitis, and myalgia as the predominant symptoms and a mortality of 4.6%. Among confirmed cases, 41% received a single dose and 20% received two doses of the KFD vaccine. Of the seven districts with KFDV positivity, Shivamogga and Hassan districts reported KFD viral RNA positivity in humans, monkeys, and ticks. Sequencing analysis of 2019 cases demonstrated a difference of less than 1.5% amino acid compared to prototype KFDV. CONCLUSION: Although the KFD has been endemic in many districts of Karnataka state, our study confirms the presence of KFDV for the first time in two new districts, i.e. Hassan and Mysore. A comparative analysis of KFDV infection among the KFD-vaccinated and non-vaccinated populations demonstrated an insignificant difference.

Sociodemographic factors associated with Kyasanur forest disease in India - a retrospective study.

Objectives: Kyasanur forest disease (KFD) is a tick-borne disease in India affecting humans and two local non-human primate species. A critical knowledge gap in the scientific literature is the lack of information on how people's sociodemographic factors influence KFD occurrence. Methods: We analyzed available data on KFD from three data sources: (a) 104 peer-reviewed articles using keyword searches on PubMed Central and Google Scholar, (b) 116 Program for Monitoring Emerging Diseases reports, and (c) an acute febrile illness surveillance data set on KFD from a report by the government of India. We performed statistical analyses to calculate the prevalence of KFD by state and differences in KFD cases by sex and age group. Results: All three data sets used indicate that KFD cases and deaths have occurred predominantly in the 15-64 years age group (literature: 87% cases and 95% deaths, Program for Monitoring Emerging Diseases: 78% cases and 78% deaths, acute febrile illness: 96% cases [no breakdown for acute febrile illness death data]). Data reporting varies across states and is non-standardized. Conclusions: The inconsistent reporting of sociodemographic data on KFD in India has created a gap in our understanding of its impact on different social groups. Collecting and reporting data on sociodemographic factors is critical to understanding the epidemiology of KFD and designing effective public health interventions.

A Case Series on the Spectrum of Complications Observed in Kyasanur Forest Disease.

Background Kyasanur Forest Disease (KFD) has emerged as an important differential diagnosis of febrile illness for physicians caring for patients in the Western Ghats of South India over the last decade.  Aim This study seeks to familiarize physicians with the clinical presentation and the clinical, laboratory and imaging findings of the various complications of KFD. It also seeks to review the literature on the complications of KFD described. Material and methods This was a records-based retrospective study of the patients with KFD referred for tertiary care management to Government Medical College Kozhikode, Kerala over 11 years, from January 2013 to December 2023. Results A total of 12 case records were obtained and analysed. All the patients in this case series belonged to tribal ethnic groups enhancing its social significance. The complications of KFD (as calculated in the 11 patients for whom all the records were available) were altered sensorium (nine, 82%), persistent shock (seven, 64%), Acute Respiratory Distress Syndrome (ARDS)/pneumonitis (six, 55%), encephalitis (six, 55%), myocarditis (six, 55%), bleeding manifestations (six, 55%), hepatitis (six, 55%), acute kidney injury (four, 36%), rhabdomyolysis (three. 27%), hemophagocytic lymphohistiocytosis (HLH) (two, 18%), stress hyperglycaemia (two, 18%), pancreatitis (one, 9%), peritonitis (one, 9%). The case fatality rate in this series was 42%( n=5/12). An autopsy was done on one patient which showed congested and oedematous lungs with subpleural haemorrhage. Petechial haemorrhages were noted in the liver, spleen and kidney. The total leucocyte count was lower than 2500 c/mm3 in 10 (90%) patients. Out of the four patients in whom serum ferritin was tested, it was elevated (above 500 ng/ml) in all patients; and was above 1000 ng/ml in three patients. Hemophagocytic lymphohistiocytosis was diagnosed in two patients. This is a unique finding of our series. Both of these patients succumbed to the illness. A cerebrospinal fluid study was done in six patients and revealed normal values except in one patient. Troponin assays were done in seven patients and were positive in five patients indicating that myocarditis is a major contributor to shock, which is one of the commonest complications in KFD. Serum creatinine phosphokinase ranged from 656 to 23,000 U/L. Conclusions Altered sensorium was the most common alarming symptom that warrants referral to a higher centre. The major organ involvements that dominated the clinical presentation and course of illness were neurological complications, hypotension, significantly contributed by myocarditis and acute respiratory distress syndrome/pneumonitis. Encephalitis, myocarditis, ARDS and HLH were the major complications that caused mortality in our series. The elevated serum ferritin and the mortality associated with HLH described need further research to investigate the role of the macrophage system in the pathogenesis of severe KFD.

Computational Exploration of Potential Pharmacological Inhibitors Targeting the Envelope Protein of the Kyasanur Forest Disease Virus.

The limitations of the current vaccination strategy for the Kyasanur Forest Disease virus (KFDV) underscore the critical need for effective antiviral treatments, highlighting the crucial importance of exploring novel therapeutic approaches through in silico drug design. Kyasanur Forest Disease, caused by KFDV, is a tick-borne disease with a mortality of 3-5% and an annual incidence of 400 to 500 cases. In the early stage of infection, the envelope protein plays a crucial role by facilitating host-virus interactions. The objective of this research is to develop effective antivirals targeting the envelope protein to disrupt the virus-host interaction. In line with this, the 3D structure of the envelope protein was modeled and refined through molecular modeling techniques, and subsequently, ligands were designed via de novo design and pharmacophore screening, yielding 12 potential hits followed by ADMET analysis. The top five candidates underwent geometry optimization and molecular docking. Notably, compounds L4 (SA28) and L3 (CNP0247967) are predicted to have significant binding affinities of -8.91 and -7.58 kcal/mol, respectively, toward the envelope protein, based on computational models. Both compounds demonstrated stability during 200 ns molecular dynamics simulations, and the MM-GBSA binding free-energy values were -85.26 ± 4.63 kcal/mol and -66.60 ± 2.92 kcal/mol for the envelope protein L3 and L4 complexes, respectively. Based on the computational prediction, it is suggested that both compounds have potential as drug candidates for controlling host-virus interactions by targeting the envelope protein. Further validation through in-vitro assays would complement the findings of the present in silico investigations.