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Scrub typhus is a common bacterial infection in Asia caused by Orientia tsutsugamushi. This serological cohort study estimated the incidence of infection in a rural population in South India. Participants were enrolled through systematic sampling in 46 villages at baseline, and revisited the following year. Blood samples were tested for IgG antibodies using ELISA, followed by indirect immunofluorescence assays (IFA) in those positive for ELISA at both rounds. A case was defined as sero-conversion (ELISA), or at least a 4-fold titre increase (IFA), between the two time points. In addition to crude incidence rate estimates, we used piecewise linear rates across calendar months, with rates proportional to the monthly incidence of local hospital cases to address seasonality and unequal follow-up times. Of 402 participants, 61.7% were female. The mean age was 46.7 years, (range 13-88). 21 participants showed evidence for serological infection. The estimated incidence was 4.4 per 100 person-years (95% CI 2.8-6.7). The piecewise linear rates approach resulted in a similar estimate of 4.6 per 100 person years (95% CI 2.9-6.9). Considering previous estimates of symptomatic scrub typhus incidence in the same study population, only about 2-5% of infections may result in clinically relevant disease. [ABSTRACT FROM AUTHOR]

The article presents a study on the bacterium Orientia tsutusgamushi in India from September 2010 to August 2012. The study identified its genetic diversity and molecular epidemiology by collecting eschar samples from patients with scrub typhus who were submitted to 56-kDa type-specific polymerase chain reaction (PCR) and sequencing in three regions, such as Northeast, Northern and South India. Findings suggest that it could enhance region-specific diagnostic studies and vaccine development.

The article describes the case of a 48-year old male who was diagnosed with cerebral venous sinus thrombosis presentation in severe scrub typhus infection. The results of the patient's neurological examination, chest x-ray, and cranial magnetic resonance imaging (MRI) are presented. Also discussed are the clinical outcome after treating the patient with doxycycline, azithromycin, unfractionated heparin and anti-edema measures. The characteristics eschar seen in scrub typhus are described.

This study aimed to assess the molecular prevalence of mite-borne zoonotic pathogen O. tsutsugamushi in household rats of South India through nested polymerase chain reaction amplification of O. tsutsugamushi 47-kDa htrA gene and to determine the most suitable sample type for screening of O. tsutsugamushi in rats. Out of 85 rats trapped in Tamil Nadu, Karnataka, and Puducherry regions, 47 rats were found positive for the O. tsutsugamushi genome with prevalence of 55.29 %. Among different sample types screened, faecal samples exhibited the highest positivity rate, followed by liver, spleen, kidney, and blood samples. Agreement between faecal and spleen samples of rats for the presence of O. tsutsugamushi was the highest. Principal component analysis revealed a positive correlation between the spleen, liver, and faeces and a negative correlation between blood and faeces for the presence of O. tsutsugamushi genome. These findings underscore the varied distribution of O. tsutsugamushi among different samples and indicate that the faecal and liver samples of rats are an ideal choice of samples for epidemiological studies. This is the first study to report a high level of presence of O. tsutsugamushi in faecal samples of rats., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: The appropriate antibiotic treatment for severe scrub typhus, a neglected but widespread reemerging zoonotic infection, is unclear., Methods: In this multicenter, double-blind, randomized, controlled trial, we compared the efficacy of intravenous doxycycline, azithromycin, or a combination of both in treating severe scrub typhus. Patients who were 15 years of age or older with severe scrub typhus with at least one organ involvement were enrolled. The patients were assigned to receive a 7-day course of intravenous doxycycline, azithromycin, or both (combination therapy). The primary outcome was a composite of death from any cause at day 28, persistent complications at day 7, and persistent fever at day 5., Results: Among 794 patients (median age, 48 years) who were included in the modified intention-to-treat analysis, complications included those that were respiratory (in 62%), hepatic (in 54%), cardiovascular (in 42%), renal (in 30%), and neurologic (in 20%). The use of combination therapy resulted in a lower incidence of the composite primary outcome than the use of doxycycline (33% and 47%, respectively), for a risk difference of -13.3 percentage points (95% confidence interval [CI], -21.6 to -5.1; P = 0.002). The incidence with combination therapy was also lower than that with azithromycin (48%), for a risk difference of -14.8 percentage points (95% CI, -23.1 to -6.5; P<0.001). No significant difference was seen between the azithromycin and doxycycline groups (risk difference, 1.5 percentage points; 95% CI, -7.0 to 10.0; P = 0.73). The results in the per-protocol analysis were similar to those in the primary analysis. Adverse events and 28-day mortality were similar in the three groups., Conclusions: Combination therapy with intravenous doxycycline and azithromycin was a better therapeutic option for the treatment of severe scrub typhus than monotherapy with either drug alone. (Funded by the India Alliance and Wellcome Trust; INTREST Clinical Trials Registry-India number, CTRI/2018/08/015159.)., (Copyright © 2023 Massachusetts Medical Society.)

Background and Objectives: To determine the real-world data regarding the use of Rituximab (RTX) in neuroinflammatory disorders (NIDS) and assess the outcomes following RTX treatment., Methods: A cohort of consecutive patients with NIDS started on RTX (2018-2020) was included. The outcomes assessed were the proportion with favourable clinical response (FCR) as defined by clinical remission/ improvement using disease specific disability scores, comparative efficacy based on timing of initiation and B cell kinetics., Results: A total of 97 patients with NIDS were included. The mean age was 36.43 (±14.4) years and median duration of follow - up being 15 months (IQR 12-16). Forty patients (41.2%) were initiated on RTX "early" in disease course. Favourable clinical response at last follow-up was seen in 94.9% (n = 92). The mean change in disability score (mRS) was 1.89 (SD 1.30) (p < 0.001). RTX appeared more effective when initiated "early" with higher remission rates (75% vs. 42%, p 0.015). B cell kinetics varied across NIDS, with 73% having adequate depletion at 6 months. Minor adverse events including infusion related reactions were reported in 9%., Conclusions: RTX has a favourable efficacy and safety profile. Future prospective studies are needed to establish the optimal timing of initiation and need for disease-based dosage regimens., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: To evaluate a treponemal enzyme-linked immunosorbent assay (ELISA) as an alternative screening test for syphilis in pregnant women., Methods: A cross-sectional study of diagnostic test accuracy was carried out in a large volume laboratory from a tertiary care center. A total of 416 serum samples, including 102 archived syphilis Treponema pallidum hemagglutination (TPHA)-positive samples and 314 samples from pregnant women, were used to determine the sensitivity and specificity of ELISA. All the samples were subjected to Venereal Disease Research Laboratory (VDRL), rapid plasma reagin (RPR), ELISA, and TPHA tests. Performance characteristics of VDRL, RPR, and ELISA were calculated with TPHA as a reference standard test., Results: VDRL and RPR exhibited higher false positivity of 10.5% and 9.6%, respectively, compared to 2.5% by ELISA. The sensitivity and specificity of ELISA were 98% and 97.5%, of VDRL were 71.6% and 89.5%, and of RPR were 73.5% and 90.5%, respectively. Moreover, ELISA had an excellent agreement (kappa=0.9) with TPHA compared to VDRL/RPR which had a moderate agreement (kappa=0.6) only., Conclusion: ELISA has the potential to replace VDRL/RPR as a screening test for syphilis in centers that can perform ELISA, especially for antenatal screening., (© 2020 International Federation of Gynecology and Obstetrics.)

Serial twofold dilution methods are most commonly used to identify the antimicrobial activities of antibiotics. This can be achieved by different methods like broth dilution or agar dilution. Though these methods are simple, they can be influenced by various experimental factors and result in discrepancy. The following protocol has been validated for Acinetobacter species, including A. baumannii. It is important to include appropriate control strains to determine the minimum inhibitory concentration values and to compare the experiment results.

Objectives: Scrub typhus is endemic in the Asia-Pacific region. Mortality is high even with treatment, and further knowledge of the immune response during this infection is needed. This study was aimed at comparing plasma levels of monocyte/macrophage and endothelial related inflammatory markers in patients and controls in South India and to explore a possible correlation to disease severity and clinical outcome., Methods: Plasma levels of ALCAM, VCAM-1, sCD163, sCD14, YKL-40 and MIF were measured in scrub typhus patients (n = 129), healthy controls (n = 31) and in infectious disease controls (n = 31), both in the acute phase and after recovery, by enzyme immunoassays., Results: Patients had markedly elevated levels of all mediators in the acute phase, differing from both healthy and infectious disease controls. During follow-up levels of ALCAM, VCAM-1, sCD14 and YKL-40 remained elevated compared to levels in healthy controls. High plasma ALCAM, VCAM-1, sCD163, sCD14, and MIF, and in particular YKL-40 were all associated with disease severity and ALCAM, sCD163, MIF and especially YKL-40, were associated with mortality., Conclusions: Our findings show that scrub typhus is characterized by elevated levels of monocyte/macrophage and endothelial related markers. These inflammatory markers, and in particular YKL-40, may contribute to disease severity and clinical outcome., (Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

Objectives: This study sought to document the clinical and laboratory manifestations, genetic variability, and outcomes of scrub typhus, an often severe infection caused by Orientia tsutsugamushi, in South India., Methods: Patients admitted to a large teaching hospital with IgM ELISA-confirmed scrub typhus were evaluated. Clinical examination with a thorough search for an eschar, laboratory testing, chest X-ray, and outcome were documented and analyzed. Additionally, a 410-bp region of the 56-kDa type-specific antigen gene of O. tsutsugamushi was sequenced and compared with isolates from other regions of Asia., Results: Most of the 154 patients evaluated presented with fever and non-specific symptoms. An eschar was found in 86 (55%) patients. Mild hepatic involvement was seen in most, with other organ involvement including respiratory, cardiovascular, and renal. Multi-organ dysfunction was noted in 59 (38.3%), and the fatality rate was 7.8%. Hypotension requiring vasoactive agents was found to be an independent predictor of mortality (p<0.001). The phylogeny of 26 samples showed 17 (65%) clustering with the Kato-like group and eight (31%) with the Karp-like group., Conclusions: The presentation of scrub typhus can be variable, often non-specific, but with potentially severe multi-organ dysfunction. Prompt recognition is key to specific treatment and good outcomes. Further study of the circulating strains is essential for the development of a successful vaccine and sensitive point-of-care testing., (Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

We report the first laboratory-confirmed human infection due to a new rickettsial genotype in India, "Candidatus Rickettsia kellyi," in a 1-year-old boy with fever and maculopapular rash. The diagnosis was made by serologic testing, polymerase chain reaction detection, and immunohistochemical testing of the organism from a skin biopsy specimen.