First case of scrub typhus with meningoencephalitis from Kerala: An emerging infectious threat

Disseminated central nervous system tuberculoma in a patient with scrub typhus: A case report

Central nervous system (CNS) tuberculosis mainly manifests as tuberculous meningitis and intracranial tuberculosis; intramedullary tuberculosis is uncommon. Scrub typhus is an acute naturally occurring infectious disease caused by Orientia tsutsugamushi. CNS tuberculoma following typhus is rare. The present study described a 60-year-old man with high fever, muscle soreness, yellowish skin and sclera and hepatosplenomegaly. At first, the patient was diagnosed with scrub typhus, after treatment with doxycycline he recovered completely. However, half a month after discharge, the patient experienced headache, night sweats and anorexia. Tuberculosis-specific enzyme-linked immunospot assay showed positive Mycobacterium tuberculosis antibody in cerebrospinal fluid (CSF). Metagenomic next-generation sequencing detected the presence of Mycobacterium tuberculosis in CSF. Magnetic resonance imaging of the brain and spinal cord showed multiple rings enhancing lesions in the cerebral hemispheres, cerebellum, brainstem and spinal cords. After the diagnosis of CNS tuberculoma, the patient was started on conventional anti-tuberculosis therapy resulting in a good prognosis.

Meningoencephalitis: A Rare Presentation of Scrub Typhus

Scrub typhus is a mite-born acute febrile illness endemic to a part of the world known as the “tsutsugamushi triangle,” which also includes Nepal. It has a wide range of presentations with multiple organ involvement, including meningoencephalitis. We present a unique case of a 30-year-old lady with scrub typhus meningoencephalitis, which showed drastic improvement with doxycycline. This case highlights the importance of high suspicion in an endemic area with limited diagnostic facilities. With the early initiation of empirical therapy, fatal complications of scrub typhus infection such as meningoencephalitis can be prevented.

Neurological Manifestations of Scrub Typhus: A Case Series from Tertiary Care Hospital in Southern East Rajasthan

Scrub typhus is an acute febrile infectious illness caused by rickettsia species Orientia tsutsugamushi. In recent years, scrub typhus has reemerged as a life-threatening disease in India Scrub typhus has diverse clinical manifestations ranging from a nonspecific febrile illness to severe multiorgan dysfunction, and neurological complications are also common. Spectrum of neurological complications varies from common complications such as aseptic meningitis, meningoencephalitis and cerebellitis to rare complications such as myelitis, cerebral hemorrhage, acute disseminated encephalomyelitis (ADEM), and cerebral infarction. Scrub typhus is not a common cause of acute febrile illness in state like Rajasthan, but has emerged as a life-threatening disease in recent years along with dreaded neurological complications. This case series highlights various neurological manifestations of scrub typhus as early diagnosis and treatment of neurological complications have good prognosis.

Seroprevalence & seroincidence of Orientia tsutsugamushi infection in Gorakhpur, Uttar Pradesh, India: A community-based serosurvey during lean (April-May) & epidemic (October-November) periods for acute encephalitis syndrome

Background & objectives

In India, acute encephalitis syndrome (AES) cases are frequently reported from Gorakhpur district in Uttar Pradesh. Scrub typhus is one of the predominant aetiological agents for these cases. In order to delineate the extent of the background of scrub typhus seroprevalence and the associated risk factors at community level, serosurveys during both lean and epidemic periods (phase 1 and phase 2, respectively) of AES outbreaks were conducted in this region.

Methods

Two community-based serosurveys were conducted during lean (April-May 2016) and epidemic AES (October-November 2016) periods. A total of 1085 and 906 individuals were enrolled during lean and epidemic AES periods, respectively, from different villages reporting recent AES cases. Scrub typhus-seronegative individuals (n=254) during the lean period were tested again during the epidemic period to estimate the incidence of scrub typhus.

Results

The seroprevalence of Orientia tsutsugamushi during AES epidemic period [immunoglobulin (Ig) IgG: 70.8%, IgM: 4.4%] was high as compared to that of lean AES period (IgG: 50.6%, P <0.001; IgM: 3.4%). The factors independently associated with O. tsutsugamushi positivity during lean AES period were female gender, illiteracy, not wearing footwear, not taking bath after work whereas increasing age, close contact with animals, source of drinking water and open-air defecation emerged as additional risk factors during the epidemic AES season. IgM positivity was significantly higher among febrile individuals compared to those without fever (7.7 vs. 3.5%, P=0.006). The seroincidence for O. tsutsugamushi was 19.7 per cent, and the subclinical infection rate was 54 per cent.

Interpretation & conclusions

The community-based surveys identified endemicity of O. tsutsugamushi and the associated risk factors in Gorakhpur region. The findings will be helpful for planning appropriate interventional strategies to control scrub typhus.

Diagnostic tools used in the evaluation of acute febrile illness in South India: a scoping review

BACKGROUND

Acute febrile illness (AFI) is characterized by malaise, myalgia and a raised temperature that is a nonspecific manifestation of infectious diseases in the tropics. The lack of appropriate diagnostics for the evaluation of AFI leads to increased morbidity and mortality in resource-limited settings, specifically low-income countries like India. The review aimed to identify the number, type and quality of diagnostics used for AFI evaluation during passive case detection at health care centres in South India.

METHODS

A scoping review of peer-reviewed English language original research articles published between 1946-July 2018 from four databases was undertaken to assess the type and number of diagnostics used in AFI evaluation in South India. Results were stratified according to types of pathogen-specific tests used in AFI management.

RESULTS

The review included a total of 40 studies, all conducted in tertiary care centres (80% in private settings). The studies demonstrated the use of 5-22 tests per patient for the evaluation of AFI. Among 25 studies evaluating possible causes of AFI, 96% tested for malaria followed by 80% for dengue, 72% for scrub typhus, 68% for typhoid and 60% for leptospirosis identifying these as commonly suspected causes of AFI. 54% studies diagnosed malaria with smear microscopy while others diagnosed dengue, scrub typhus, typhoid and leptospirosis using antibody or antigen detection assays. 39% studies used the Weil-Felix test (WFT) for scrub typhus diagnosis and 82% studies used the Widal test for diagnosing typhoid.

CONCLUSIONS

The review demonstrated the use of five or more pathogen-specific tests in evaluating AFI as well as described the widespread use of suboptimal tests like the WFT and Widal in fever evaluation. It identified the need for the development of better-quality tests for aetiological diagnosis and improved standardised testing guidelines for AFI.

Occurrence of Orientia tsutsugamushi, the Etiological Agent of Scrub Typhus in Animal Hosts and Mite Vectors in Areas Reporting Human Cases of Acute Encephalitis Syndrome in the Gorakhpur Region of Uttar Pradesh, India

Outbreaks of acute encephalitis syndrome (AES) with high fatality and disability, are reported every year in the Gorakhpur region of Uttar Pradesh, India, with the etiology of >60% of the cases being attributed to scrub typhus. In the present study, the prevalence of Orientia tsutsugamushi, the etiological agent of scrub typhus, was investigated among animal hosts and their ectoparasitic trombiculid mites prevalent in AES-reported areas of Gorakhpur. A total of 154 rodents/shrews were collected using 777 Sherman traps set in 12 study villages, and the overall trap rate was 19.8%. In total, 2726 trombiculid mites belonging to 12 species were collected from 154 rodents/shrews trapped. The shrew mouse Suncus murinus was the predominant animal species (78.6%) collected. The principal vector mite Leptotrombidium deliense was the predominant species (82.7%), and its index was 14.6 per animal. Of 114 rodent/shrew sera samples screened through the Weil-Felix test, 57% were positive for antibodies against O. tsutsugamushi. Of 128 blood samples tested by polymerase chain reaction (PCR), one rodent sample was positive for the gene encoding 56 kDa protein and 25 for 60 kDa. Among 2726 mite samples tested as 315 pools through nested PCR, seven pools were positive for 56 kDa gene. Phylogenetic analysis confirmed circulation of Gilliam, Karp, and TA678 serotypes of O. tsutsugamushi in Gorakhpur. The study clearly demonstrated natural infection of O. tsutsugamushi in both small-animal hosts and vector mites in the AES-reporting villages of Gorakhpur, which confirms transmission of the scrub typhus pathogen in this region. The high infestation rate of L. deliense with O. tsutsugamushi infection indicates that the people living in the rural villages of Gorakhpur are at risk of infection with scrub typhus, which might lead to AES.

Clinical manifestations of scrub typhus

The mite-borne rickettsial zoonosis scrub typhus is widely prevalent in parts of Southeast and Far East Asia, and northern Australia. The disease is an acute febrile illness, associated with rash and often an eschar, which responds dramatically to treatment with antibiotics. In some cases it results in a serious illness leading to multiple organ involvement and death. The disease manifestations are thought to result from a systemic vasculitis, caused by both direct effects of the organisms as well as an exaggerated immune response, although little is understood about its pathogenesis. A wide spectrum of clinical manifestations, affecting nearly every organ system, have been described with scrub typhus. Some of these manifestations are serious and life threatening. In this systematic review, we summarise the typical and atypical manifestations of scrub typhus reported in the literature. Awareness of these unusual manifestations will hopefully guide clinicians towards diagnosing the condition early, and initiating early appropriate antibiotics and other supportive measures.

Prevalence and clinical presentation of Rickettsia, Coxiella, Leptospira, Bartonella and chikungunya virus infections among hospital-based febrile patients from December 2008 to November 2009 in Bangladesh

BACKGROUND

We conducted a study to identify Rickettsia, Coxiella, Leptospira, Bartonella, and Chikungunya virus infections among febrile patients presenting at hospitals in Bangladesh.

METHODS

We collected blood samples from patients at six tertiary hospitals from December 2008 to November 2009 and performed laboratory tests at the United States Centers for Disease Control and Prevention (CDC).

RESULTS

Out of 720 enrolled patients, 263 (37%) were infected with Rickettsia; 132 patients had immunofluorescence antibody titer >64 against spotted fever, 63 patients against scrub typhus fever and 10 patients against typhus fever. Ten patients were identified with Coxiella. We isolated Leptospira from two patients and Bartonella from one patient. Ten patients had antibodies against Chikungunya virus. The proportion of patients who died was higher with rickettsial fever (5%) compared to those without a diagnosis of rickettsial infection (2%). None of the patients were initially diagnosed with rickettsial fever.

CONCLUSIONS

Rickettsial infections are frequent yet under-recognized cause of febrile illness in Bangladesh. Clinical guidelines should be revised so that local clinicians can diagnose rickettsial infections and provide appropriate drug treatment.

An Unusual Presentation of Scrub Typhus

Presentation of scrub typhus associated with brachial neuritis is extremely rare with only a few cases reported so far. Here, we report a case of a 45-year-old female who presented with fever and right shoulder pain. Laboratory parameters showed leucocytosis with ELISA and PCR for scrub typhus positive. Electromyography (EMG) and Nerve Conduction Velocity (NCV) study was suggestive of brachial neuritis. She was given doxycycline therapy for 10 days following which her shoulder pain resolved.

Seroprevalence of Scrub Typhus Infection in Arunachal Pradesh, India

INTRODUCTION

Scrub typhus is a major reason for febrile illness, caused by a bacterium Orientia tsutsugamushi, a rickettsial pathogen. Few outbreaks of scrub typhus have been reported from Arunachal Pradesh in recent past. However, there is lack of seroprevalence data from the region. In this regard, this study was undertaken using archival serum sample available from seven districts of Arunachal Pradesh.

METHODOLOGY

This serological study was conducted in Regional Medical Research Center for NE Region, Dibrugarh. Reactivity to IgG class of antibodies against scrub typhus was done using Scrub typhus detect IgG ELISA kit as per manufacturer's protocol.

RESULT

Seroprevalence of scrub typhus in seven districts of Arunachal Pradesh was found to be 40% (120/300). The age-specific scrub typhus seroprevalence rose steadily from 5.6% in children <10 years of age to 61.8% in persons aged ≥40 years (p = 0.0001). Prevalence is lowest in Papumpare (25.9%) and highest in East Siang (72.5%) (p = 0.0001). The seroprevalence in males and females was very similar, however, the female prevalence increases from age group ≥30 years (p = 0.053). Moreover, among the farmers, the seroprevalence is higher (58.3%) (p = 0.0001).

CONCLUSIONS

As clinical symptoms overlap with other viral/bacterial infections, scrub typhus infection should be considered in differential diagnosis of any acute febrile illness in this part of the country. In view of the high prevalence, empirical therapy of doxycycline/azithromycin may be done in cases of undiagnosed fever. Active surveillance has to be done to understand exact magnitude, epidemiological aspects, and distribution of vector and disease of this reemerging neglected tropical disease.

CNS Manifestations in Orientia tsutsugamushi Disease (Scrub Typhus) in North India

OBJECTIVE

To present the clinical, lab profile and outcome of a series of six children who had features of meningoencephalitis (median age of 10.5 y) diagnosed as confirmed scrub typhus (ST) by using a lgM ELISA commercial kit (InBiOS International Inc. USA).

METHODS

This was a prospective observational study conducted at a tertiary care hospital, over a period of 7 mo through April 2014. All the patients with undifferentiated febrile illness (aged 1-18 y) with fever of 5-21 d duration were evaluated. After thorough physical examination they were subjected to blood investigations such as complete blood count (CBC), blood culture, hepatic and kidney function tests, serum electrolytes, cerebrospinal fluid (CSF) analysis and IgM ELISA for scrub typhus, coagulogram and chest radiograph, wherever indicated.

RESULTS

During this period, of the total 81 confirmed cases based on a positive scrub IgM ELISA and/or eschar, 6 (7.4 %), had neurological involvement in the form of presence of neck stiffness, altered sensorium and/or seizures and the CSF findings were suggestive of meningoencephalitis and all had evidence of multiple organ dysfunction syndrome (MODS) needing intensive care. The CECT could be performed in four patients only showing evidence of effacement of sulci and evidence of brain edema.

CONCLUSIONS

This communication highlights that variable central nervous system (CNS) involvement is not uncommon in patients with scrub typhus with high mortality. CSF and neuro-radiology findings are nonspecific as these are also observed in patients with aseptic meningitis or encephalitis. Early suspection and institution of appropriate therapy without delay will lead to substantial reduction in the morbidity and mortality.

Serodiagnosis of Scrub Typhus at a Tertiary Care Hospital from Southern India

INTRODUCTION

Scrub typhus, a zoonotic disease is one of the most covert emerging and re-emerging Rickettsial infections. There is an upsurge in the incidence of the disease worldwide with ever-changing habitat. Clinical diagnosis of scrub typhus is challenging as the signs and symptoms of scrub typhus are similar to other febrile illnesses. In developing countries, among the various laboratory tests to diagnose scrub typhus, Weil-Felix test is commonly performed despite its low sensitivity. The Immunofluorescence antibody (IFA) test has its limitations in terms of cost and expertise required. The present study was conducted to determine the seropositivity of IgM ELISA for scrub typhus in clinically suspected cases.

MATERIALS AND METHODS

Weil-Felix test and IgM ELISA were performed using clinically suspected cases of scrub typhus using commercially available kits.

RESULTS

Out of 482 samples tested, 109 were positive by both Weil-Felix test and IgM ELISA. One hundred and sixteen samples which were negative by Weil-Felix test reacted positive by IgM ELISA. Fourteen samples which were positive by Weil-Felix test were negative by ELISA.

CONCLUSION

Owing to the limitations of the Weil-Felix test and IFA, commercially available recombinant IgM ELISA which has a good sensitivity and specificity may be an alternative in laboratories with moderate set up.

Molecular epidemiology and genetic diversity of Orientia tsutsugamushi from patients with scrub typhus in 3 regions of India

Clarifying local antigenic diversity is critical for development of region-specific vaccines and diagnostics.

Scrub typhus, an acute febrile illness that is widespread in the Asia-Pacific region, is caused by the bacterium Orientia tsutsugamushi, which displays high levels of antigenic variation. We conducted an investigation to identify the circulating genotypes of O. tsutsugamushi in 3 scrub typhus–endemic geographic regions of India: South India, Northern India, and Northeast India. Eschar samples collected during September 2010–August 2012 from patients with scrub typhus were subjected to 56-kDa type-specific PCR and sequencing to identify their genotypes. Kato-like strains predominated (61.5%), especially in the South and Northeast, followed by Karp-like strains (27.7%) and Gilliam and Ikeda strains (2.3% each). Neimeng-65 genotype strains were also observed in the Northeast. Clarifying the genotypic diversity of O. tsutsugamushi in India enhances knowledge of the regional diversity among circulating strains and provides potential resources for future region-specific diagnostic studies and vaccine development.

Neurological manifestations of scrub typhus

OBJECTIVE

To evaluate the neurological manifestations of scrub typhus and correlate their clinical, EEG and MRI findings.

METHODS

A cross-sectional study over 2 years included patients with scrub typhus diagnosed by solid phase immunochromatographic assay or Weil-Felix test. A detailed clinical evaluation including Glasgow Coma Scale (GCS) was documented. Blood counts, chemistry, ECG, chest radiograph, cerebrospinal fluid (CSF), EEG and cranial MRI were performed. Outcome on discharge and at 1 month were categorised into good and poor based on modified Rankin Scale.

RESULTS

Thirty-seven patients with ages ranging between 3 and 71 years were included; 51% of whom were females. All patients had fever and myalgia. Thirty-one (84%) patients had impaired consciousness, and six were deeply comatose (GCS score ≤8). Eight patients presented with status epilepticus. MRI revealed meningeal enhancement in only 1/25 (4%) patient and EEG showed generalised slowing in 6/28 (21.4%). Among 31 patients with altered sensorium, CSF studies were conducted on 28. Nineteen patients had meningoencephalitis and 9 encephalopathy, but no significant differences were observed in clinical, laboratory, EEG and MRI findings. All patients responded within 48 h to doxycycline and had good recovery at 1 month. Patients with low GCS score had significantly more focal neurological deficit (r=0.5; p=0.002), longer hospital stay (r=-0.4; p=0.03) and more disability on discharge (r=-0.4; p=0.01).

CONCLUSIONS

Meningoencephalitis/encephalopathy may be seen in two-third of patients with scrub typhus. Scrub typhus should be included in the differential diagnosis of febrile encephalopathy.

Emerging vector-borne zoonoses: eco-epidemiology and public health implications in India

The diseases originating from animals or associated with man and animals are remerging and have resulted in considerable morbidity and mortality. The present review highlights the re-emergence of emerging mainly zoonotic diseases like chikungunya, scrub typhus, and extension of spatial distribution of cutaneous leishmaniasis from western Rajasthan to Himachal Pradesh, Kerala, and Haryana states; West Nile virus to Assam, and non-endemic areas of Japanese encephalitis (JE) like Maharashtra and JE to Delhi; Crimean-Congo hemorrhagic fever making inroads in Ahmedabad; and reporting fifth parasite of human malaria with possibility of zoonosis have been highlighted, which necessitates further studies for prevention and control. Emphasis has been given on understanding the ecology of reservoir hosts of pathogen, micro niche of vector species, climatic, socioeconomic risk factors, etc. Development of facilities for diagnosis of virus from insects, reservoirs, and human beings (like BSL4, which has been established in NIV, Pune), awareness about symptoms of new emerging viral and other zoonotic diseases, differential diagnosis, risk factors (climatic, ecological, and socioeconomic) and mapping of disease-specific vulnerable areas, and mathematical modeling for projecting epidemiological scenario is needed for preparedness of public health institutes. It is high time to understand the ecological link of zoonotic or anthroponotic diseases for updated risk maps and epidemiological knowledge for effective preventive and control measures. The public health stakeholders in India as well as in Southeast Asia should emphasize on understanding the eco-epidemiology of the discussed zoonotic diseases for taking preventive actions.

Acute encephalitis syndrome following scrub typhus infection

Objective:

The aim was to find the incidence of acute encephalitis syndrome (AES) secondary to scrub infection and to observe the clinical, biochemical, radiological profile, and outcomes in these patients.

Materials and Methods:

A total of 20 consecutive patients of AES were evaluated for scrub infection using scrub typhus immunoglobulin M enzyme linked immuno-sorbant assay positivity along with the presence or absence of an eschar. Clinical profile, routine laboratory tests, cerebrospinal fluid (CSF) analysis, and neuroimaging were analyzed. Patients were treated with doxycycline and followed-up.

Results:

Among 20 consecutive patients with AES, 6 (30%) were due to scrub infection. They presented with acute onset fever, altered sensorium, seizures. Eschar was seen in 50% of patients. CSF done in two of them was similar to consistent with viral meningitis. Magnetic resonance imaging brain revealed cerebral edema, bright lesions in the putamen and the thalamus on T2-weighted and fluid-attenuated inversion recovery sequences. Renal involvement was seen in all patients. All patients responded well to oral doxycycline.

Conclusion:

AES is not an uncommon neurological presentation following scrub typhus infection. It should be suspected in all patients with fever, altered sensorium, and renal involvement. Oral doxycycline should be started as early as possible for better outcomes.

Scrub typhus meningitis in South India--a retrospective study

Background

Scrub typhus is prevalent in India although definite statistics are not available. There has been only one study on scrub typhus meningitis 20 years ago. Most reports of meningitis/meningoencephalitis in scrub typhus are case reports

Methods

A retrospective study done in Pondicherry to extract cases of scrub typhus admitted to hospital between February 2011 and January 2012. Diagnosis was by a combination of any one of the following in a patient with an acute febrile illness- a positive scrub IgM ELISA, Weil-Felix test, and an eschar. Lumbar puncture was performed in patients with headache, nuchal rigidity, altered sensorium or cranial nerve deficits.

Results

Sixty five cases of scrub typhus were found, and 17 (17/65) had meningitis. There were 33 males and 32 females. Thirteen had an eschar. Median cerebrospinal fluid (CSF) cell count, lymphocyte percentage, CSF protein, CSF glucose/blood glucose, CSF ADA were 54 cells/µL, 98%, 88 mg/dL, 0.622 and 3.5 U/mL respectively. Computed tomography was normal in patients with altered sensorium and cranial nerve deficits. Patients with meningitis had lesser respiratory symptoms and signs and higher urea levels. All patients had received doxycycline except one who additionally received chloramphenicol.

Conclusion

Meningitis in scrub typhus is mild with quick and complete recovery. Clinical features and CSF findings can mimic tuberculous meningitis, except for ADA levels. In the Indian context where both scrub typhus and tuberculosis are endemic, ADA and scrub IgM may be helpful in identifying patients with scrub meningitis and in avoiding prolonged empirical antituberculous therapy in cases of lymphocytic meningitis.