Case report of scrub typhus complicated by hypokalemia and multiple organ dysfunction syndrome

ABSTRACT CONTEXT: Scrub typhus, caused by Orientia tsutsugamushi, has a wide range of clinical manifestations, including meningoencephalitis, acute renal failure, pneumonitis, myocarditis, and septic shock. However, there are no documented cases of scrub typhus with hypokalemia. In this report, we present a case of scrub typhus with hypokalemia and multiple organ failure syndrome, highlighting the importance of electrolyte imbalance in patients with scrub typhus. CASE REPORT: A 59-year-old woman presented to the emergency department with abdominal pain that had been present for 1 day. On admission, the physical examination and laboratory test results indicated that the patient had renal, liver, and circulatory failure, and hypokalemia. She developed meningitis and disseminated intravascular coagulation during hospitalization. She recovered with appropriate management, and was discharged on day 17. CONCLUSION: This report highlights the potential for atypical presentations of scrub typhus, including a previously undocumented association with hypokalemia. Although the contribution of hypokalemia to the patient's clinical course remains uncertain, this case underscores the importance of considering electrolyte imbalance in the management of patients with scrub typhus. Further research is warranted to better understand the relationship between scrub typhus and electrolyte imbalance.

Diagnostic Accuracy of Rapid Antibody Detection Test for Scrub Typhus

Objectives: To detect the diagnostic accuracy of rapid antibody detection test using IgM immunochromatography for scrub typhus in children. Methods: This cross-sectional study enrolled children aged 2 months-18 years hospitalized over a period of 18 months with undifferentiated fever of duration five days or more. The blood samples were subjected to serological tests like Weil-Felix, Scrub IgM ELISA, immunofluroscence assay (IFA) and rapid diagnostic test (IgM Immunochromatography). Diagnostic accuracy was measured against IFA as the gold standard. Results: A total of 90 children were included in the study, among which 43 children were positive for gold standard test IFA. Rapid diagnostic test showed sensitivity of 88.3%, specificity of 89.3%, positive predictive value of 88.3% and negative predictive value of 89.3%. The sensitivity, specificity, PPV and NPV of Weil-Felix test was 39.5%, 84.2%, 58.6 and 71.1%, respectively and of IgM ELISA was 93%, 89.3%,88.8% and 93.3%, respectively. Conclusion: IgM immunochromatography had good diagnostic accuracy for scrub typhus in children with acute undifferentiated fever.

Costs & outcomes of hospitalized scrub typhus infection in a tertiary hospital in south India

Background & objectives: Scrub typhus is a rickettsial infection seen along the Asian-Pacific rim and imposes a considerable burden on affected people in low- and middle-income countries. The present study was aimed to determine the direct cost of hospitalization of scrub typhus and its trend over six years. Methods: This was a retrospective, observational, hospital based study of individuals admitted to the hospital, diagnosed with scrub typhus over six years, from January 2013 to December 2018. The potential out of pocket expenditure was evaluated. Results: A total of 198 patients were included in the study. The median cost of admission (adjusted to INR 2020) for the six years (2013 to 2018) was found to be ? 37,026 (US $ 490) [interquartile range (IQR) 22,996-64,992]. The median cost for patients admitted to the intensive care unit (ICU) was ? 128,046 (US $ 1695) (IQR 71,575-201,171), while the cost for patients admitted to the ward-alone was ? 33,232 (US $ 440) (IQR 19,609-45,373). The multivariable analysis showed that ARDS and SOFA score were the independent predictors of ICU admission. Interpretation & conclusions: Hospitalisation for scrub typhus is associated with a substantial healthcare expense. The predictors of increased cost were the presence of acute respiratory distress syndrome (ARDS), shock, increasing sequential organ failure assessment (SOFA) score and duration of hospital stay

Determination of a cut-off value for the serological diagnosis of scrub typhus by detecting anti-Orientia tsutsugamushi immunoglobulin M

Background & objectives: The diagnosis of scrub typhus (ST) is usually done using enzyme-linked immunosorbent assay (ELISA) due to its ease of performance and reading objectivity. The cut-off value for ELISA needs to be calculated for each geographical location as it depends on zonal endemicity of the disease. This study was, therefore, undertaken to calculate the pan-India cut-off for anti-Orientia tsutsugamushi (OT) immunoglobulin M (IgM) by ELISA. Methods: Samples from cases (cases of ST) and controls (voluntary, consenting, healthy adults) were collected by a network of 29 laboratories across India and tested for anti-OT IgM by immunofluorescence assay (IFA), the considered gold standard test. These samples were retested by ELISA for anti-OT IgM and their optical densities (ODs) were used for cut-off estimation by receiver operating characteristic (ROC) curve. Results: Anti-OT IgM ELISA ODs from 273 controls and 136 cases were used for the cut-off estimation. The ODs of the anti-OT IgM ELISA on healthy individuals and those of confirmed ST cases ranged from 0.1 to 0.75 and 0.5 to 4.718, respectively. ROC curve-based cut-off for ELISA was calculated as 0.554 at a sensitivity of 95.2 per cent and specificity of 95.1 per cent. A value of >1 was noted to have a specificity of 100 per cent in diagnosing ST. Interpretation & conclusions: The cut-off calculated for India was similar to the previous cut-off that was used until now.

Differentiating Multisystem Inflammatory Syndrome in Children (MIS-C) and Its Mimics – A Single-Center Experience From a Tropical Setting

Objective: Identifying clinical and laboratory indicators that differentiate multisystem inflammatory syndrome in children (MIS-C) apart from other febrile diseases in a tropical hospital setting. Methods: Review of hospital records done in a tertiary care exclusive children’s hospital for children admitted from April, 2020 till June, 2021. Laboratory values, severe acute respiratory syndrome coronavirus (SARS-CoV-2) serological status, and clinical signs and symptoms of patients with MIS-C, and those with similar presentations were analyzed. Results: 114 children fulfilled the inclusion criteria (age group of 1 mo-18 y) for whom a diagnosis of MIS-C was considered in the emergency room based on the clinical features. Among them, 64 children had the final diagnosis of MIS-C, and the remaining 50 children had confirmatory evidence of infections mimicking MIS-C such as enteric fever, scrub typhus, dengue and appendicitis. Conclusion: Older age group, presence of mucocutaneous symptoms, very high C-reactive protein, neutrophilic leukocytosis, abdominal pain and absence of hepatosplenomegaly favor a diagnosis of MIS-C.

Scrub Typhus Presenting as Subdural Hemorrhage with Normal Platelet Counts: A Rare Case Presentation

Scrub typhus is a common zoonotic disease with high case fatality rate. The clinical presentation of this disease may vary from acute febrile illness, thrombocytopenia, gastrointestinal manifestations, coagulopathy to neurological manifestations. The common neurological manifestations are meningitis and meningoencephalitis, whereas subdural hemorrhage, cerebrovascular accident, i.e., intracerebral hemorrhage, infarct, subarachnoid hemorrhage, etc. are among rare neurological presentations. Scrub typhus-induced neurological disease should be investigated to provide a timely and appropriate diagnosis and to reduce the mortality in complicated scrub typhus infection. Here we report a case of scrub typhus complicated with subdural hemorrhage admitted in our hospital.

Monitoring Weil–Felix test in epidemic retinitis

Purpose: The objective was to study the positivity of the Weil–Felix test (WFT) in epidemic retinitis (ER) during the course of the disease. Methods: This is a retrospective, observational case series of patients diagnosed with ER and presented to a tertiary eye care hospital in south India. Patients with positive WFT at the presentation, and who underwent a follow?up WFT during or after the resolution of ER were studied from September 2019 to March 2022. Patient’s demographics, timings of clinical presentation and resolution, and investigation details with a special focus on WFT positivity and its duration were noted. Results: Sixteen patients were studied. Patients presented after 5 weeks of the fever (range: 2?12 weeks, median: 4). After 1?2 months, WFT was still positive in eight patients (50%). Only in one patient titers increased after 1 month, while in others, the titers decreased (n = 11) or remained the same (n = 4). Repeated tests in those patients (n = 6) after 3?4 months turned negative. Resolution of ER was seen at 1.35 months (range: 1?3 months) after the presentation. The mean duration for WFT to turn negative was 2 months from the presentation (range: 1?4 months) or 3.2 months of the fever (range: 1.5?6 months). Conclusion: In contrast to the reported physician’s observation of increasing titers of WFT after rickettsial fever, ophthalmologists may observe decreasing WFT titers in ER. The clinical resolution of ER may precede the normalization of WFT. Follow?up WFT titers should be studied in larger series in confirmed cases of rickettsial?ER to validate the affordable and readily available WFT in India

Fauna of scrub typhus vector chigger mites in Yunnan Province / 中国热带医学

@#Abstract: Chigger mites belong to the phylum Arthropoda, class Arachnida, sub-class Acari, order Parasitiformes, family Trombiculidae and Leeuwenhoekiidae, with a wide range of species. There are more than 3 700 known species of mites globally, of which 531 species in 46 genera from three sub-families have been recorded in China, and 320 species of chigger mites recorded from 3 subfamilies and 32 genera in Yunnan Province. At this stage, chigger mites are the only vectors of scrub typhus, with about 60 species worldwide being potential vectors. Six vectorial mite species have been confirmed in China, including Leptotrombidium deliense, L.scutellare, L.rubellum, L.sialkotense, L.kaohuense, L.insulare. Yunnan Province has reported five vectorial mite species, including the previously-mentioned five species except for L.sialkotense. The zoogeographic study divided Yunnan Province into 5 zoogeographic areas, namely, Central Hengduan Mountains subregion, Southern Hengduan Mountains subregion, Eastern Yunnan Plateau subregion, Western Yunnan Plateau subregion, Southern Yunnan Mountainous subregion. The Southern Hengduan Mountains subregion has the highest number of known genera and species of scrub typhus and the highest number of scrub typhus cases, with 216 species in 22 genera from 3 subfamilies, and all 5 species of vector scrub typhus were distributed. Southern Yunnan Mountain subregion has the least number of mite species, with 91 species in 12 genera from three sub-families, with L. scutellare being the dominant vectorial mite species across the province. Due to suitable natural geographic conditions in Yunnan Province, vectorial mites can propagate rapidly, leading to a large number of scrub typhus cases. According to statistics, the number of scrub typhus cases in Yunnan Province has rapidly increased, with 15.40 times, 20.64 times and 28.91 times more cases in 2016, 2017 and 2018 respectively than in 2006. Scrub typhus remains a serious public health problem in Yunnan Province, posing a threat to the health of the local population. Therefore, prevention and control efforts should continue to focus on the affected areas and the general public.

Analysis of clinical characteristics of scrub typhus associated with hemophagocytic syndrome in 15 children / 中国热带医学

@#Abstract: Objective　To analyze the clinical features of hemophagocytic syndrome (HPS) associated with Orientia tsutsugamushi disease in children. Methods　The case data of patients with scrub typhus in Kunming Children's Hospital from January 1st 2019 to December 31st 2021 was retrospectively analyzed. The patients were divided into the HPS group and the non-HPS group according to whether associated with HPS. The clinical data of the two groups were analyzed using SPSS 25.0. Results　Eighty-five cases of scrub typhus in children were collected, 15 cases (17.6%) had HPS. The mean age of patients with HPS was (5.10±3.82) years, included 9 males and 6 female, there was no significant difference in gender and age between the HPS and the non-HPS group (P>0.05). Comparison of the two groups indicted that the incidence of cough, lung rales, edema, and hepatomegaly were significantly increased in the HPS group (P<0.05). The data showed that compared to the non-HPS group, the HPS group showed significant decreases in the levels of hemoglobin (HGB), platelet (PLT), albumin (ALB), fibrinogen (Fib) (P<0.05), and significant decreases in the levels of C-reactive protein (CRP), lactic dehydrogenase (LDH), triglyceride (TG), serum ferritin (SF) (P<0.05). The proportion of CD4+ T lymphocytes, CD4+/CD8+ were significantly decreased (P<0.05); the proportion of CD3+, CD8+ T lymphocytes were significantly increased (P<0.05). The proportion of pulmonary exudation or consolidation in the HPS group was higher than the non-HPS group, which was statistically significant (P<0.05). All the patients with scrub typhus associated with HPS were treated with oral doxycycline, and intravenous immunoglobulin was given in 13 cases (86.7%). There was one case of death and 14 cases discharged from hospital after treatment in HPS group. Conclusion　HPS in scrub typhus infected children is a nonnegligible complication. Prolonged fever, lung rales, hepatomegaly，HGB decreased, thrombocytopenia, hyperferritinemia, and abnormal lymphocyte subsets may associate with HPS. It should be alerted to scrub typhus when presenting with HPS in endemic areas. The scrub typhus associated with HPS can be successfully treated with appropriate antibiotic and immunomodulator treatment.

Research progress on the epidemiology of tsutsugamushi disease of summer type in China / 预防医学

@#Tsutsugamushi disease, also known as scrub typhus, is a zoonosis caused by Orientia tsutsugamushi, with rats as the main sources of infection and chigger mites as the only medium of transmission, and has no effective vaccines. Tsutsugamushi disease can be divided into summer, autumn and winter types according to seasons in China, while the summer type is characterized by strong virulence, typical and severe symptoms, high rates of misdiagnosis and mortality. The summer type of tsutsugamushi disease is distributed in the south of 31°N in China, with the epidemic time from June to August, and the cases are predominantly females, farmers and people at ages of over 40 years. Affected by natural environment, social and economic factors, the epidemic areas and the number of cases of summer type of tsutsugamushi disease are increasing continuously. Based on publications pertaining to the epidemiology of summer type of tsutsugamushi disease in China from 1960 to 2023, this review summarizes the mechanism of transmission, epidemiological characteristics and influencing factors, so as to provide the basis for prevention and control of summer type of tsutsugamushi disease in China.

Clinico-demographic Profile and Outcome of Scrub Typhus in North Eastern State of India

Scrub typhus is a form of bacterial Zoonosis caused by Orintia tsutsugamushi usually presents as Acute febrile illness with multiorgan involvement as a complication and is associated with significant mortality. This study aims to document the clinico-demographic profile, laboratory parameters and complication of Scrub Typhus in North Eastern Hilly State of Tripura with background of tropical climate. This retrospective study was conducted at Tripura Medical College, including 42 patients admitted with acute febrile illness between June, 2020 to December, 2021 during the era of COVID-19 Pandemic. The diagnosis was established by Rapid card test, Lateral Flow Metry Assay (LFA) followed by confirmation through IgM, ELISA test and pathognomic Eschar where feasible. The clinlical, demographic and laboratory profile were documented and analysed. Post rainy season and people from rural area with farming background were mostly affected population. Apart from Fever and Flu like symptom, respiratory and Gastrointestinal (GI) symptoms were more prominent feature. Pathognomic skin lesion eschar was found in maximum cases followed by shortness of breath, GI involvement and Renal failure. Acute Respiratory Distress Syndrome (ARDS), Acute Kidney Injury (AKI), Hepatic encephalopathy and meningitis were the serious complications. While evaluating cases of acute febrile illness with multiorgan involvement clinician should have high index of suspicion for Scrub typhus specially resource poor areas of North Eastern (NE) state of India so that early detection and time bound intervention may help to reduce the mortality

Scrub Typhus Associated with Guillain–Barré Syndrome (GBS)

Scrub typhus is a vector-borne disease caused by Orientia tsutsugamushi. Clinical manifestations generally occur due to vasculitis and infammation and can have variable degrees of systemic involvement. Meningoencephalitis and cerebellitis are well-known neurological manifestations of scrub typhus, but the occurrence of Guillain–Barré syndrome is extremely rare. The authors report a 7-y-old boy who developed fever followed by rapidly progressive ascending quadriparesis with arefexia and whose etiological workup revealed positive IgM scrub typhus antibody, as well as, a high OXK titer (1:80). Nerve-conduction studies in all four limbs were suggestive of demyelinating neuropathy. He showed complete recovery after treatment with intravenous immunoglobulin (2 g/kg) and azithromycin.

An atypical presentation of scrub typhus

Scrub typhus is caused byOrientia tsutsugamushi, characterised by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system.The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillain-Barre syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhusis limited to case reports mainly. This article shows a case report of neurological manifestations of scrub typhus.

Vector and rodent surveillance for Orientia tsutsugamushi in north India

Background & objectives: Scrub typhus or chigger borne typhus, caused by Orientia tsutsugamushi is an emerging vector-borne disease as large numbers of cases have been reported in various tropical countries. It is transmitted to humans through bites of infected chiggers (larval mites). The knowledge about the vector, its distribution, density and habitat are important so as to understand the epidemiology of scrub typhus in a given area. To control rickettsial infections, regular rodent-vector surveillance should be planned in areas where the disease transmission is occurring and it will also help to strengthen the existing entomological data related to the vector of scrub typhus in northern India. Methods: In the present study, rodent-vector surveillance was planned for one whole year, covering both mite active and non-active seasons (October 2019–December 2020) in selected areas of Chandigarh and Punjab in north India. Rodent tissues and mites were also examined for the presence of O. tsutsugamushi by nested PCR for 56 kDa gene and real-time PCR for 47 kDa outer membrane protein gene. 18S gene PCR was performed for molecular identification of mites. Results: In the surveillance, three types of ectoparasite, viz. mites, fleas and ticks were obtained in rodents. All mites found were of Laelapidae family. None of the pooled rodent tissue samples as well as mite samples were found positive for O. tsutsugamushi by nested PCR for rickettsial DNA. Interpretation & conclusion: In the present study, we did not get any evidence of carriage of O. tsutsugamushi in either mites or rodents collected and sampled in selected regions in Chandigarh and Punjab. We need to strengthen the entomological surveillance over a broader region and increase the frequency of trapping rodents to increase clarity on vector-reservoir dynamics in this geographical region.

Emerging trends of scrub typhus disease in southern Rajasthan, India: A neglected public health problem

Scrub typhus is the oldest known vector-borne zoonotic infectious disease in the world which is life-threatening for all age groups as it presents acute febrile illness along with multi-organ involvements and spread with the biting of infectious ‘Trombiculid mite’ (chigger mite). The pathogen of this disease is an obligatory coccobacillus gram-negative rickettsial bacteria Orientia tsutsugamushi. Scrub typhus disease was previously confined geographically only to the Asia Pacific region (tsutsugamushi triangle), but in recent years it has crossed its limit and has spread in other countries beyond the tsutsugamushi triangle and has become more hazardous for the community. The objective of this study is to explore the scrub typhus disease outbreak trends with existing information in southern Rajasthan state, India. This study concluded that scrub typhus disease is being re-emerged again and again in various Indian geographical regions with new species of vectors. The disease has been raised in tremendous amounts in Rajasthan within the last five years especially in the hilly zone and has led to major public health problems with other zoonotic diseases

Dengue and Scrub Typhus Co-infection in Children: Experience of a Teaching Hospital in an Endemic Area

Background: Dengue fever and scrub typhus are considered an endemic disease in the Indian subcontinent. The epidemiology and clinical presentations are complex and vary each year.? Objective: The objective of this study was to estimate the prevalence of coinfection with scrub typhus in children diagnosed with dengue fever. Methods: A retrospective hospital-based, cross-sectional study was done in the Department of Pediatrics of a teaching hospital in Puducherry. All children (0–14 years) who had enzyme?linked immunosorbent assay (ELISA) reported scrub typhus among those diagnosed with dengue fever (NS1Ag or immunoglobulin M ELISA positivity) during 2012–2016. Medical records with incomplete data were excluded from the study. Odds ratio was calculated to find out the association of coinfections. An independent t-test was used to find out the statistical significance. P < 0.05 was considered statistically significant. Results: Atypical features of dengue were present in 250/318 (78.6%) children. Coinfections were seen in 62/318 (19.4%) children. Scrub typhus was the most common (n = 51/62, 82.2%). The chance of scrub typhus in a dengue serology?positive child is significant when the symptoms are atypical or protracted (OR– 2.6, P = 0.033). Conclusion: High index of suspicion should be present in endemic dengue and scrub typhus coinfection.

A clinico-epidemiological profile of scrub typhus cases admitted in a tertiary hospital in South India

Scrub typhus (ST) is a consistently underreported disease. The disease is spreading to newer areas, and an understanding of disease epidemiology is needed in the local Indian and current context. This study describes the demographic characteristics, monthly distribution, clinical and laboratory presentations, and treatment outcome of the ST cases recently identified. Case sheets of 15 ST patients diagnosed from January 2019 to December 2020 were analyzed. The majority of the patients were male. Eighty percent of the patients were from rural or suburban areas. Higher admission was observed from September to December. Fever (100%), skin rash (73.3%), body ache (53.3%), and vomiting (53.3%) were the most common clinical features. The onset of fever till the appearance of skin rash was 3 ± 1.2 days. The mean day from onset of symptoms till diagnosis was 6.8 ± 3.9 days. Eschar was found in only two patients. Nine (60%) patients already had complications at the time of admission. Most patients presented a laboratory picture of thrombocytopenia, neutrophilic leukocytosis, and anemia. Complications such as septic shock, acute kidney injury, and hepatic involvement were observed. All responded to doxycycline within 48 h. No fatalities were observed. Early clinical suspicion of ST among those with high fever, skin rash and thrombocytopenia, and transaminitis showed positive clinical outcome.

A rare case of scrub typhus vasculitis presenting as acute coronary syndrome diagnosed by skin manifestations

A 48-year-old diabetic man presented with complaints of acute onset chest heaviness with palpitations, anxiety and headache. He had raised troponin-T level and electrocardiogram showed ST elevation myocardial infarction. There was a prior history of fever of 4 days duration with associated abdominal pain. He later developed skin rash and neurological symptoms following admission to the hospital. Dermatological examination revealed purpura and a livedo-like rash. Investigations revealed deranged liver and renal function tests and positive serological tests for scrub typhus. Coronary angiography revealed no evidence of atherosclerosis or any other pathology. He was therefore diagnosed as a case of scrub typhus-induced vasculitis with coronary manifestations and was managed with oral doxycycline. Scrub typhus presenting like an acute coronary syndrome has been reported very rarely previously. In addition, patient had gastrointestinal, central nervous system and hematological involvement which added to the rarity of the case.

A Multiplex PCR assay for a differential diagnostic of rickettsiosis, Lyme disease and scrub typhus

Background & objectives: Coexistence of tick-borne diseases in some regions in Latin America makes the diagnosis difficult due to shared initial signs and symptoms. Rickettsiosis, Lyme disease and recently, scrub typhus are gaining more importance. The objective of this study is to develop a multiplex-PCR assay for a differential diagnosis of rickettsiosis, Lyme disease and scrub typhus. Methods: By using bibliographic and bioinformatic analysis, we identify candidate regions to perform the multiplexPCR assay for Rickettsia sp., Borrelia burgdorferi and Orientia tsutsugamushi as well as identify optimal melting temperature and sensibility analysis. Results: We identified specific primer pairs for Rickettsia sp, Borrelia burgdorferi and Orientia tsutsugamushi with different PCR fragment length but a common melting temperature, 58°C. Interpretation & conclusion: We successfully developed a Multiplex PCR assay for differential diagnosis of rickettsiosis, Lyme disease and scrub typhus that could be a rapid and easy option in clinical and epidemiological practice.Laboratorio de Enfermedades Infecciosas y Parasitarias 1. Unidad Interinstitucional de Investigación Clínica y Epidemiológica, Facultad de Medicina, Universidad Autónoma de Yucatán. Yucatán, Mexico

Laboratorio de Enfermedades Emergentes y Re-emergentes. Centro de Investigaciones Regionales “Dr. Hideyo Noguchi”. Universidad Autonoma de Yucatan. Yucatán, Mexico

Molecular epidemiology of Orientia tsutsugamushi from outbreak regions, Madhya Pradesh, central India

Scrub typhus is a seriously neglected life threatening disease in Asia and the islands of the Pacific and Indian oceans. The causative agent is Orientia tsutsugamushi, an obligate intra-cytosolic bacterium transmitted to vertebrate animals such as human or rodent by larval trombiculid mites (chiggers). Here, we conducted an outbreak investigation in Madhya Pradesh state in central India after sudden upsurge in scrub typhus cases and mortality in humans. Sixty-five live traps were placed for capturing the rodents. The captured rodent species were identified and the samples were subjected to nested PCR targeting 56kDa TSA gene. Analysis revealed for the first-time predominant circulation of Karp genotype in this region. The vector species involved in transmission is Leptotrobidium deliense. In conclusion, we reported the circulation of Karp strain in outbreak regions of Madhya Pradesh and suggest that public health monitoring and surveillance needs to be improved. Studies on antigenic diversity, association of strains with clinical spectrum and pathogenicity in the local setup will be essential for development of region-specific diagnostics and vaccines.