Figure - available from: Current Microbiology
This content is subject to copyright. Terms and conditions apply.
Microscopic images of Leptospira interrogans 2016-001 after 2 months of incubation in Mont-Dore® water (left panel) and Leptospira biflexa Patoc I 4 mpi in Volvic® water (right panel). Observations were made under a Leica DM4000 fluorescence microscope using Live/Dead® BacLightTM Bacterial Viability Kit. Magnification ×1000
Source publication
Mostly studied as a zoonosis, leptospirosis is also an environment-borne infection and most human cases originate from soil or water contaminations. Yet, only few studies have been interested in the survival of pathogenic Leptospira in freshwater. In this study, water microcosms were designed to evaluate the survival and virulence of Leptospira spp...
Similar publications
Background and Aim
Leptospirosis is a re-emerging zoonosis that is under-reported in tropical countries, and canines can be a potential reservoir of the disease. The objective of this study was to diagnose Leptospira spp. that is actively infected and re-infected in stray dogs and cats from Bogota, D.C., Colombia.
Materials and Methods
A sample of...
Background
Leptospirosis is a zoonosis caused by spirochete “genus” leptospira. The clinical presentations of leptospirosis range from an influenza-like presentation of fever and myalgia, to severe forms. Leptospirosis can potentially lead to a misdiagnosis or delay in diagnosis when clinical similarities exist.
Case presentation
A 63-year-old man...
Leptospira interrogans are pathogenic bacteria responsible for leptospirosis, a zoonosis impacting 1 million people per year worldwide. Leptospires can infect all vertebrates, but not all hosts develop similar symptoms. Human and cattle may suffer from mild to acute illnesses and are therefore considered as sensitive to leptospirosis. In contrast,...
Background
Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate...
Background
Leptospirosis is a worldwide zoonosis caused by the spirochete Leptospira interrogans. The clinical presentations of leptospirosis range from an influenza-like presentation of fever and myalgia, to severe forms. Leptospirosis can potentially lead to a misdiagnosis or delay in diagnosis when clinical similarities exist.
Case presentation...
Citations
... It uniquely possesses lipopolysaccharide (LPS), which facilitates spirochetal survival in dry environments by preserving water for cells (10,103). Leptospires can persist in diverse environmental conditions (Figure 1a) and are maintained in fresh water in nature (9). Like B. burgdorferi, L. interrogans poses a significant risk to humans due to frequent occupational or recreational exposures during the spring to fall months (38). ...
The major human spirochetal pathogens (Leptospira, Borrelia, and Treponema) are difficult to diagnose and lack vaccines to prevent infections. Infection by these spirochetes does not generate general protective immunity, allowing reinfection by different strains to occur. These stealth pathogens have uncommon physiology, pathogenesis, and clinical presentations and possess unique immune evasion mechanisms to facilitate their host adaptation and persistence. Collectively, host-spirochete interactions orchestrate systemic infections in a manner distinct from organ- and tissue-specific diseases caused by many bacterial pathogens. Difficulties in growing and genetic manipulation of infectious spirochetes have hindered the full understanding of their virulence factors despite decades to centuries of research. This article highlights the current understanding of the intricacies of spirochetal pathogenesis and diseases. Our comprehensive review of the progress versus gaps in knowledge lays a foundation for researchers to direct their studies toward the development of effective diagnostics and vaccines to protect patients from serious, chronic spirochetal diseases.
... This runoff, which consists of effluents from sewage treatment, septic tanks, and animal husbandry, enters coastal lagoons and estuaries, posing critical threats to these vital ecosystems. The San Juan Bay Estuary (SJBE), a significant ecological center located within these watersheds, is essential to the integrity of the coastline, especially its mangrove This disease accounts for approximately 60,000 yearly fatalities (Bierque et al., 2020). Humans and other animals become susceptible to infection upon exposure to contaminated water, often filled with bacterium-laden urine (Pappas et al., 2008;Rawlins et al., 2014). ...
... The concurrent occurrence of fecal waste and urine contamination in environmental samples implies that surface water containing high nitrogen and phosphorous from fecal runoff may also contain higher concentrations of Leptospira that is carried in the urine of infected host (Bierque et al., 2020;Fouts et al., 2016). Another aim of this study was to determine the relationship among nutrient levels, MST of human, horse and dog fecal contamination, and qPCR detection of pathogenic Leptospira in SJBE. ...
This study investigated the relationship between nutrient levels, source of fecal contamination, and pathogenic Leptospira in Puerto Rico’s northern coast and San Juan Bay Estuary (SJBE) aquatic ecosystems. Microbial source tracking (MST) was also used to investigate the connections between sources of feces contamination and the presence of Leptospira. Eighty-seven water samples were collected during the June (n=44) and August (n=43) in 2020. To quantify phosphorus and nitrogen concentrations, standard USEPA protocols were utilized, specifically Methods 365.4 for total and dissolved phosphorus, 351.2 for total Kjeldahl nitrogen and ammonium, and 353.2 for nitrate. Lipl32 gene-specific quantitative polymerase chain reaction (qPCR) was used to detect the presence of Leptospira. Human (HF183), canine (BacCan-UCD), and equine (HoF597) MST assays were utilized to trace the origins of fecal contamination. Forty one percent of the locations exceeded Puerto Rico’s authorized total phosphorus limit of 160 g L−1, while 34% exceeded the total nitrogen limit of 1700 g L−1. Nearly half of the streams examined are affected by eutrophication. The MST analysis identified human and canine feces as the most prevalent contaminants, affecting approximately 50% of the sites. In addition, Leptospira was detected in 32% of the June samples. There was a significant correlation (r = 0.79) between the incidence of pathogenic Leptospira and the human bacterial marker (HF183). This study illuminates the central role of anthropogenic inputs in nutrient enrichment and pathogen proliferation in Puerto Rico’s aquatic ecosystems.
... colonize the renal proximal tubules of reservoir hosts and are shed in the urine, contaminating the environment (Yamaguchi et al., 2018;Sato et al., 2022). Their ability to survive in water and soil, and infect a wide range of host species, including humans and wild and domestic animals, has made leptospirosis a zoonotic disease of increasing importance worldwide (Picardeau, 2017;Bierque et al., 2020). Upon infection, leptospires can traverse tissue barriers to rapidly disseminate to all organs, including the eyes and brain (Coburn et al., 2021). ...
Leptospira interrogans disseminates hematogenously to reach the target organs by disrupting epithelial adherens junctions (AJs), thus causing leptospirosis, which is a globally neglected zoonotic disease. L. interrogans induces E-cadherin (E-cad) endocytosis and cytoskeletal rearrangement during AJ disassembly, but the detailed mechanism remains unknown. Elucidation of AJ disassembly mechanisms will guide new approaches to developing vaccines and diagnostic methods. In this study, we combine proteomic and imaging analysis with chemical inhibition studies to demonstrate that disrupting the AJs of renal proximal tubule epithelial cells involves the degradation of two armadillo repeat-containing proteins, p0071 and p120-catenin, that stabilize E-cad at the plasma membrane. Combining proteasomal and lysosomal inhibitors substantially prevented p120-catenin degradation, and monolayer integrity destruction without preventing p0071 proteolysis. In contrast, the pan-caspase inhibitor Z-VAD-FMK inhibited p0071 proteolysis and displacement of both armadillo repeat-containing proteins from the cell-cell junctions. Our results show that L. interrogans induces p120-catenin and p0071 degradation, which mutually regulates E-cad stability by co-opting multiple cellular degradation pathways. This strategy may allow L. interrogans to disassemble AJs and disseminate through the body efficiently.
... Interestingly, these have seldomly been isolated from environmental sources. However, studies indicated their ability to persist in soils for an extended period of time (Smith and Self, 1955;Okazaki and Ringen, 1957;Hellstrom and Marshall, 1978;Thibeaux et al., 2017;Stone et al., 2022), with intact capability to induce infection (Bierque et al., 2020a). The remaining 61 Leptospira species were all found in environmental sources, and most were exclusively isolated from the environment, highlighting their propensity to thrive and persist in natural environments. ...
Leptospira is a complex bacterial genus which biodiversity has long been overlooked. In the recent years however, environmental studies have contributed to shed light on its original and current environmental habitat. Although very fragile bacteria in laboratories, Leptospira have been shown to successfully occupy a range of soil and freshwater habitats. Recent work has strongly suggested that biofilm formation, a multicellular lifestyle regulated by the second messenger c-di-GMP, might be one strategy developed to overcome the multiple challenges of environmental survival. Within the genus, a minority of pathogenic species have developed the ability to infect mammals and be responsible for leptospirosis. However, most of them have retained their environmental survival capacity, which is required to fulfill their epidemiological cycle. Indeed, susceptible hosts, such as human, suffer from various symptoms, while reservoir hosts stay asymptomatic and release bacteria in the environment. In this review, we discuss how c-di-GMP might be a central regulator allowing pathogenic Leptospira to fulfill this complex life cycle. We conclude by identifying knowledge gaps and propose some hypotheses that should be researched to gain a holistic vision of Leptospira biology.
... On the other hand, agricultural areas may be suitable environments for the bacteria because of greater vegetation cover, humidity and wet soils [62,64,67]. Instead, urban environments may be heterogeneous in terms of environmental suitability since leptospiral survival would be favored in green spaces that provide shaded areas, puddles, moist soils, and lower temperatures than those sectors where pavement and buildings predominate [62,[68][69][70][71]. Therefore, the association between human leptospirosis and landscape heterogeneity determinants was considered positive. ...
Background:
Leptospirosis is among the leading zoonotic causes of morbidity and mortality worldwide. Knowledge about spatial patterns of diseases and their underlying processes have the potential to guide intervention efforts. However, leptospirosis is often an underreported and misdiagnosed disease and consequently, spatial patterns of the disease remain unclear. In the absence of accurate epidemiological data in the urban agglomeration of Santa Fe, we used a knowledge-based index and cluster analysis to identify spatial patterns of environmental and socioeconomic suitability for the disease and potential underlying processes that shape them.
Methods:
We geocoded human leptospirosis cases derived from the Argentinian surveillance system during the period 2010 to 2019. Environmental and socioeconomic databases were obtained from satellite images and publicly available platforms on the web. Two sets of human leptospirosis determinants were considered according to the level of their support by the literature and expert knowledge. We used the Zonation algorithm to build a knowledge-based index and a clustering approach to identify distinct potential sets of determinants. Spatial similarity and correlations between index, clusters, and incidence rates were evaluated.
Results:
We were able to geocode 56.36% of the human leptospirosis cases reported in the national epidemiological database. The knowledge-based index showed the suitability for human leptospirosis in the UA Santa Fe increased from downtown areas of the largest cities towards peri-urban and suburban areas. Cluster analysis revealed downtown areas were characterized by higher levels of socioeconomic conditions. Peri-urban and suburban areas encompassed two clusters which differed in terms of environmental determinants. The highest incidence rates overlapped areas with the highest suitability scores, the strength of association was low though (CSc r = 0.21, P < 0.001 and ESc r = 0.19, P < 0.001).
Conclusions:
We present a method to analyze the environmental and socioeconomic suitability for human leptospirosis based on literature and expert knowledge. The methodology can be thought as an evolutive and perfectible scheme as more studies are performed in the area and novel information regarding determinants of the disease become available. Our approach can be a valuable tool for decision-makers since it can serve as a baseline to plan intervention measures.
... 53 In general, existing work supports persistence of P1 leptospires in moist conditions with low UV radiation for weeks to months. [54][55][56][57] Although demonstration of Leptospira viability has traditionally required culture, "viability PCR," a novel approach that differentiates between DNA found in viable and viable cells, has also been used. Here, DNA is first treated with propidium monoazide, which removes cell-free DNA so that cell-associated DNA is available for amplification. ...
... [59][60][61][62][63] In addition, pathogenic Leptospira spp. were shown to survive over a year in water under nutrient-deprived, acidic conditions, 56,64 and viable spirochetes were also identified in soil (−2 °C) under a 40-cm-thick layer of snow in Sapporo, Japan, where the likelihood of contamination of the environment by infected animals was low. 59 Evidence has accumulated that environmental survival of pathogenic leptospires may be promoted through biofilm formation. ...
Leptospirosis is an archetypal One Health problem as described in the companion Currents in One Health article in the October 2022 issue of the Journal of the American Veterinary Medical Association by Sykes et al. A thorough understanding of leptospirosis requires a detailed analysis of the elaborate interplay among pathogenic leptospiral strains, host species, and the environment. Such an understanding is required to inform appropriate preventative measures including vaccine design, prophylaxis efforts, educational programs that help to reduce exposure to pathogenic spirochetes, as well as policy development. Because of the complex epidemiology of leptospirosis, a One Health approach as defined by the One Health Initiative Task Force is critical-an approach that calls for "the collaborative efforts of multiple disciplines working locally, nationally, and globally, to attain optimal health for people, animals and our environment." Over the last three decades, progressive advances in cutting-edge molecular typing techniques, as well as our ability to rapidly generate and share large amounts of sequence data through establishment and growth of databases, have been central to accelerating a One Health understanding of the epidemiology of leptospirosis. Nevertheless, our dependence on serotype information because of the serovar-specific nature of current vaccines means that laborious serotyping efforts continue. With the advent of new approaches such as mRNA vaccines that are based on lipopolysaccharide immunogens, sequence- and/or proteomics-based typing methods may replace these methods.
... Once excreted, Leptospira spp. can survive for months in water and moist soil (Trueba et al., 2004;Andre-Fontaine et al., 2015;Bierque et al., 2020). Humans are accidental hosts and become infected with pathogenic Leptospira upon exposure to infected animals or contaminated environmental sources. ...
Leptospirosis is an important cause of morbidity and mortality worldwide. Disease severity ranges from asymptomatic colonization to widespread hemorrhage and multiorgan dysfunction. The causative agents, Leptospira spp., are zoonotic Gram-negative spirochetes. One important step in pathogenesis is binding of bacterial adhesins to host components. Previously our laboratory identified two L. interrogans candidate adhesins, LIC11574 and LIC13411, that bind to VE-cadherin in vitro. In the current study, we demonstrate the ability of two strains of pathogenic L. interrogans to disrupt the localization of VE-cadherin, a protein important to maintaining inter-endothelial junctions. Purified MBP-LIC11574 and MBP-LIC13411 bind human dermal microvascular endothelial cells in a pattern reminiscent of VE-cadherin, but do not disrupt VE-cadherin localization. Genes encoding the candidate adhesins from pathogenic Leptospira were cloned in an overexpression vector and introduced into non-pathogenic L. biflexa, creating gain-of-function strains producing LIC11574 or LIC13411. Protein production and localization to the outer membrane were confirmed by Triton X-114 fractionation. Although these strains do not disrupt VE-cadherin localization, production of LIC13411 increases binding of non-pathogenic Leptospira to human endothelial cells and specifically to VE-cadherin. In a short-term murine model of infection, LIC13411 production led to increased burdens of the non-pathogen in the lung, liver, kidney, and bladder. These data confirm the role of LIC13411 as an adhesin in Leptospira spp. and implicate it in dissemination to multiple organs. Importantly, anti-adhesin therapy has been shown to have many benefits over classical antibiotics. Taken together, this work provides novel insight into the pathogenesis of Leptospira spp. and identifies LIC13411 as a potential prophylactic and therapeutic target.
... Although leptospirosis outbreaks have been reported after heavy rain, additional environmental and behavioral factors increase the risk of infection [17]. Bierque et al. reported that L. interrogans retains its direct virulence after long starvation in water [18]. Pathogenic Leptospira species are increansingly being isolated from environmental soils around the world [19,20]. ...
Background
Leptospirosis, a zoonosis caused by species in the spirochete genus Leptospira, is endemic to the Yaeyama region in Okinawa, subtropical Japan. Species of the P1 subclade “virulent” group, within the genus Leptospira, are the main etiological agents of leptospirosis in Okinawa. However, their environmental persistence is poorly understood. This study used a combination of bacterial isolation and environmental DNA (eDNA) metabarcoding methods to understand the eco-epidemiology of leptospirosis in this endemic region.
Findings
Polymerase chain reaction (PCR) characterized twelve human clinical L. interrogans isolates belonging to the P1 subclade “virulent” subgroup and 11 environmental soil isolates of the P1subclade “low virulent” subgroup (genetically related to L. kmetyi, n = 1; L. alstonii, n = 4; L. barantonii, n = 6) from the Yaeyama region targeting four virulence-related genes (lipL32, ligA, ligB and lpxD1). Clinical isolates were PCR positive for at least three targeted genes, while all environmental isolates were positive only for lipL32. Analysis of infected renal epithelial cells with selected clinical and environmental strains, revealed the disassembly of cell-cell junctions for the Hebdomadis clinical strain serogroup. Comparison of leptospiral eDNA during winter and summer identified operational taxonomic units corresponding to the species isolated from soil samples (L. kmetyi and L. barantonii) and additional P2 subclade species (L. licerasiae, L. wolffii-related, among others) that were not detected by soil cultivation. Total Leptospira read counts were higher in summer than in winter and the analysis of leptospiral/animal eDNA relationship suggested Rattus spp. as a potential reservoir animal.
Conclusion
Our study demonstrated high environmental Leptospira diversity in the Yaeyama region, particularly during summer, when most of the leptospirosis cases are reported. In addition, several Leptospira species with pathogenic potential were identified that have not yet been reported in Yaeyama; however, the environmental persistence of P1 subclade species previously isolated from human clinical cases in this region was absent, suggesting the need of further methodology development and surveillance.
... The bacteria establish chronic infection in the renal tubules of host animals, such as rodents and livestock, without causing significant symptoms. The pathogen is excreted through the urine (8,9), and the excreted pathogenic leptospires can survive for several months in soil and water in the absence of animal host (3,10). According to previous reports, leptospires survived up to 593 days in freshwater (11) and 183 days in water-saturated soil (12). ...
... On the other hand, saprophytic leptospires, which account for more than half species of the Leptospira genus (21), have been known to be frequently isolated only from soil and water in the environment and not from animals, suggesting that the life cycle of saprophytic leptospires can be completed solely in the environment. However, it is still unclear whether or not pathogenic and even saprophytic leptospires multiply in soil or water (3,10,22). ...
... March/April 2022 Volume 10 Issue 210.1128/spectrum.02157-21 ...
Leptospirosis is a zoonotic disease caused by infection with pathogenic leptospires. Consistent with recent studies by other groups, leptospires were isolated from 89 out of 110 (80.9%) soil or water samples from varied locations in the Philippines in our surveillance study, indicating that leptospires might have a life cycle that does not involve animal hosts. However, despite previous work, it has not been confirmed whether leptospires multiply in the soil environment under various experimental conditions. Given the fact that the case number of leptospirosis is increased after flood, we hypothesized that waterlogged soil, which mimics the postflooding environment, could be a suitable condition for growing leptospires. To verify this hypothesis, pathogenic and saprophytic leptospires were seeded in the bottles containing 2.5 times as much water as soil, and bacterial counts in the bottles were measured over time. Pathogenic and saprophytic leptospires were found to increase their number in waterlogged soil but not in water or soil alone. In addition, leptospires were reisolated from soil in closed tubes for as long as 379 days. These results indicate that leptospires are in a resting state in the soil and are able to proliferate with increased water content in the environment. This notion is strongly supported by observations that the case number of leptospirosis is significantly higher in rainy seasons and increased after flood. Therefore, we reached the following conclusion: environmental soil is a potential reservoir of leptospires.
... Annually, at least 10% of host death after Leptospira infection [3]. Leptospires can survive in untreated water for months or even years [4]. ...
Leptospirosis, caused by pathogenic Leptospira, is a global critical zoonotic disease in terms of mortality and morbidity. Vaccines are often used to prevent leptospirosis. However, few studies have reported the therapeutic effect of a vaccine against Leptospira infection. This study demonstrates the efficacy of the emergency vaccine immunization against acute leptospirosis in hamsters. Treatment with a whole-cell vaccine (Leptospira interrogans serovar Lai) at 24 h post-infection improved the survival rate of hamsters with lower leptospiral burden and minor pathological damage to organs. The vaccine also protected against multiple Leptospira serotypes acute infection. However, the protective effect of the vaccines was lost when beginning treatment at 36 h or 48 h post-infection. These results indicated that vaccines could treat acute leptospirosis in hamsters, but only if immunization is within 24 h after infection.
