Clinico-epidemiological observations of human leptospirosis from Mumbai, India

Peripartum Infections: A Position Statement of the Indian Society of Critical Care Medicine

This position statement reviews the evidence and rationale for the management of severe peripartum infections with a special focus on tropical infections and is tailored for resource-limited settings.

How to cite this article

Samavedam S, Sodhi K, Anand P, Bajwa SJS, Karnad DR, Karanth S, et al. Peripartum Infections: A Position Statement of the Indian Society of Critical Care Medicine. Indian J Crit Care Med 2024;28(S2):S92-S103.

Laboratory diagnosis and epidemiological features of leptospirosis cases in a tribal region of Western Maharashtra, India: A retrospective study

PURPOSE

Palghar district, located in the coastal region of the Konkan division of Maharashtra, has a predominantly tribal population. Leptospirosis is a major neglected public health problem and is highly underreported in Palghar district. The study aimed to evaluate the seropositivity of Leptospira infection and its associated epidemiological factors in tribal areas of the Palghar district of Maharashtra.

METHODS

The present retrospective study included 94 samples of patients clinically suspected of leptospirosis during a period of one year (2021-2022) tested at Model Rural Health Research Unit (MRHRU) Dahanu. The serum sample testing was done for the presence of specific Leptospira IgM antibodies using the Panbio™ Leptospira IgM ELISA kit. Leptospirosis seropositivity was correlated with various epidemiological risk factors.

RESULTS

A total of 12 samples of patients tested positive for specific IgM antibodies by ELISA method, indicating an overall positivity of 12.8%. Among those who tested positive, fever (83.3%), headache (58.3%), myalgia (50%), redness of the eyes (50%), and calf tenderness (16.7%) were the common symptoms observed. Subjects with redness of the eyes were significantly associated with leptospirosis (p = 0.018). The highest positivity (50%) was reported from the Ganjad area of Dahanu taluka. Farmers and animal handlers were most affected by leptospirosis.

CONCLUSION

The high proportion of Leptospirosis cases reflects the endemic nature of the disease in the Palghar district. This study shows seasonal trends in leptospirosis incidence over the year. The clinical presentation of leptospirosis may vary from sub-clinical to mild illness to severe and potentially fatal. The findings of this study will be important for achieving the overarching goal of One Health.

Clinico Epidemiological Study of Human Leptospirosis in Hilly Area of South India-A Population Based Case Control Study

Background

Leptospirosis is the most common zoonotic disease in the world affecting both animals and humans. Environmental, occupational, and sociocultural practices which vary from region to region favors the disease transmission in addition to lacunas in prompt diagnosis and treatment of cases. There are limited data on the seroprevalence of this neglected tropical disease in India. To assess the risk factors associated with Lepospirosis disease.

Materials and Methods

A population-based case control study was conducted in Kodagu district of southern India from January 2022 to March 2022. Of the 74 confirmed cases during the year 2021, 70 cases and 140 age group and gender-matched controls participated in the study. Data were collected by using semi-structured questionnaire containing details of sociodemographic, occupational, and environmental factors. The collected data were coded and exported to STATA (16.1) and analyzed by univariate and multivaiariate logistic regression to identify significant risk factors.

Results

Environmental factors such as flooding or collection of water near the house (adjusted Odds Ratio [aOR] = 4.9, confidence interval [CI]: 1.4-17.0), proximity to an open sewer (aOR = 4.9, CI: 1.2-19.1) and occupational factors such as presence of skin cuts or abrasion during work (aOR = 4, CI: 1.4-11.6), direct contact with mud or water during work (aOR = 9.7, CI: 3.3-27.7), animal farming (aOR = 3.4, CI: 1.0-11.6), presence of rodents in the house (aOR = 4, CI: 1.2-12.6), and presence of rodent habitats like grain storage area (aOR = 3.5, CI: 1.1-11.0) were significantly associated with leptospirosis.

Conclusion

Leptospirosis poses a potential public health problem in the district. Interventions like prompt diagnosis and treatment, sensitization programs, and rodent control measures will significantly control this neglected tropical disease.

Epidemiological determinants of leptospirosis in rural and urban districts of Maharashtra, India

BACKGROUND

Leptospirosis is emerging as one of the growing public health problems in many parts of India. It can occur in both rural and urban areas with varied risk factors. This study was taken up in three districts of Maharashtra namely-Mumbai, Ratnagiri, and Sindhudurg to understand the determinants of leptospirosis in both the urban and rural areas and look for differences if any.

MATERIALS AND METHODS

This cross-sectional study was carried out during the year 2017. A pretested validated questionnaire was used to collect data. Field observations were made. Eighty-seven cases from Sindhudurg and 14 from Ratnagiri and 307 cases from Mumbai were included in the study.

RESULTS

A total of 408 cases were included in the study. A total of 63 (62.4%) were males and 38 (37.6%) were females. Most cases belonged to the 20-35 year age group (37%). In rural areas, 32.7% of them visited government facilities first, whereas, in the urban areas, it was 73.9% (P = 0.006). Headache, myalgia, and prostration were more common in cases from rural areas (P = <0.05). Skin rash was found to be associated with urban cases of leptospirosis. The presence of rodents, cattle sheds, pets, and working in paddy fields were common environmental risks in rural areas, and using water for recreational activities were common in urban areas (P < 0.001).

CONCLUSIONS

Context-specific risk factors were found significantly associated with the cases. No important difference was found in the epidemiology of leptospirosis in the urban and rural areas except the source of infection.

Nucleic acid and antigen detection tests for leptospirosis

BACKGROUND

Early diagnosis of leptospirosis may contribute to the effectiveness of antimicrobial therapy and early outbreak recognition. Nucleic acid and antigen detection tests have the potential for early diagnosis of leptospirosis. With this systematic review, we assessed the sensitivity and specificity of nucleic acid and antigen detection tests.

OBJECTIVES

To determine the diagnostic test accuracy of nucleic acid and antigen detection tests for the diagnosis of human symptomatic leptospirosis.

SEARCH METHODS

We searched electronic databases including MEDLINE, Embase, the Cochrane Library, and regional databases from inception to 6 July 2018. We did not apply restrictions to language or time of publication.

SELECTION CRITERIA

We included diagnostic cross-sectional studies and case-control studies of tests that made use of nucleic acid and antigen detection methods in people suspected of systemic leptospirosis. As reference standards, we considered the microscopic agglutination test alone (which detects antibodies against leptospirosis) or in a composite reference standard with culturing or other serological tests. Studies were excluded when the controls were healthy individuals or when there were insufficient data to calculate sensitivity and specificity.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data from each study. We used the revised Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2) to assess risk of bias. We calculated study-specific values for sensitivity and specificity with 95% confidence intervals (CI) and pooled the results in a meta-analysis when appropriate. We used the bivariate model for index tests with one positivity threshold, and we used the hierarchical summary receiver operating characteristic model for index tests with multiple positivity thresholds. As possible sources of heterogeneity, we explored: timing of index test, disease prevalence, blood sample type, primers or target genes, and the real-time polymerase chain reaction (PCR) visualisation method. These were added as covariates to the meta-regression models.

MAIN RESULTS

We included 41 studies evaluating nine index tests (conventional PCR (in short: PCR), real-time PCR, nested PCR, PCR performed twice, loop-mediated isothermal amplification, enzyme-linked immunosorbent assay (ELISA), dot-ELISA, immunochromatography-based lateral flow assay, and dipstick assay) with 5981 participants (1834 with and 4147 without leptospirosis). Methodological quality criteria were often not reported, and the risk of bias of the reference standard was generally considered high. The applicability of findings was limited by the frequent use of frozen samples. We conducted meta-analyses for the PCR and the real-time PCR on blood products.The pooled sensitivity of the PCR was 70% (95% CI 37% to 90%) and the pooled specificity was 95% (95% CI 75% to 99%). When studies with a high risk of bias in the reference standard domain were excluded, the pooled sensitivity was 87% (95% CI 44% to 98%) and the pooled specificity was 97% (95% CI 60% to 100%). For the real-time PCR, we estimated a summary receiver operating characteristic curve. To illustrate, a point on the curve with 85% specificity had a sensitivity of 49% (95% CI 30% to 68%). Likewise, at 90% specificity, sensitivity was 40% (95% CI 24% to 59%) and at 95% specificity, sensitivity was 29% (95% CI 15% to 49%). The median specificity of real-time PCR on blood products was 92%. We did not formally compare the diagnostic test accuracy of PCR and real-time PCR, as direct comparison studies were lacking. Three of 15 studies analysing PCR on blood products reported the timing of sample collection in the studies included in the meta-analyses (range 1 to 7 days postonset of symptoms), and nine out of 16 studies analysing real-time PCR on blood products (range 1 to 19 days postonset of symptoms). In PCR studies, specificity was lower in settings with high leptospirosis prevalence. Other investigations of heterogeneity did not identify statistically significant associations. Two studies suggested that PCR and real-time PCR may be more sensitive on blood samples collected early in the disease stage. Results of other index tests were described narratively.

AUTHORS' CONCLUSIONS

The validity of review findings are limited and should be interpreted with caution. There is a substantial between-study variability in the accuracy of PCR and real-time PCR, as well as a substantial variability in the prevalence of leptospirosis. Consequently, the position of PCR and real-time PCR in the clinical pathway depends on regional considerations such as disease prevalence, factors that are likely to influence accuracy, and downstream consequences of test results. There is insufficient evidence to conclude which of the nucleic acid and antigen detection tests is the most accurate. There is preliminary evidence that PCR and real-time PCR are more sensitive on blood samples collected early in the disease stage, but this needs to be confirmed in future studies.

Exotic Tourist Destinations and Transmission of Infections by Swimming Pools and Hot Springs-A Literature Review

A growing number of people undertake international travel, and yet faster growth of such travel is expected in the tropics. Information on the hazards presented by pool and hot spring waters in tropical countries is very limited. This review aims to collate available information on pool water quality, alongside data on cases and outbreaks associated with swimming in pools in tropical regions affecting both local populations and travellers. Bacteria species commonly causing cases and outbreaks in the tropics as well as elsewhere in the world were excluded, and the review focuses on studies related to pathogens that, with the exception of Cryptosporidium, are unusual in more temperate climates. Studies concerning subtropical countries were included in the light of climate change. Diseases transmitted by vectors breeding in poorly maintained, neglected or abandoned pools were also included. 83 studies dealing with Microsporidia, Leptospira spp., Schistosomas spp., Cryptosporidium spp., Acanthamoeba spp., Naegleria spp., Clostridium trachomatis, viruses, and vectors breeding in swimming pool and hot tub waters, and fulfilling predefined criteria, have been included in our survey of the literature. In conclusion, prevention strategies for pool safety in the tropics are imperative. Public health authorities need to provide guidance to westerners travelling to exotic destinations on how to protect their health in swimming pools.