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1.
J Zoo Wildl Med ; 51(4): 780-788, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480558

RESUMO

Leptospirosis is a zoonotic disease with worldwide distribution caused by pathogenic Leptospira spp. Pathogenic Leptospira spp. are shed in urine of infected hosts and transmitted via ingestion of contaminated food or water, inoculation, inhalation of aerosolized urine, and absorption through mucous membranes. Leptospirosis is of particular concern in tropical and subtropical regions such as Barranquilla, Colombia. Recent reports indicate that in Barranquilla, rodents, dogs, and humans have a high leptospiral seroprevalence; and amongst zoo mammals, nonhuman primates have a high prevalence of Leptospira spp. infection. We therefore sought to determine whether primates in captivity at the Barranquilla Zoo were exposed to Leptospira spp. and whether there was a probable causal transmission link between the primates and peridomestic rodents. Samples were collected from 29 captive nonhuman primates, 15 free-ranging rats (Rattus rattus), and 10 free-ranging squirrels (Sciurus granatensis). Serum samples from primates, rats, and squirrels were evaluated via microagglutination test (MAT) vs 24 reference Leptospira serovars. Blood and urine from the primates and kidney tissue from the rats and squirrels were cultured in Ellinghausen-McCullough-Johnson-Harris (EMJH) medium and polymerase chain reaction (PCR) of lipL32 was performed to determine whether active infection was present. Leptospiral seroprevalence was found to be 66.7% (10/15) in rats, 60% (6/10) in squirrels, and 6.9% (2/29) in neotropical primates. Ateles hybridus and Ateles fusciceps had positive titers to serogroups Cynopteri and Ictohaemorrhagiae, respectively. Of the rodents that had antibodies against Leptospira spp., 90% of the rats and 66.7% of the squirrels corresponded to the serovar australis. Interestingly, all animals were culture and PCR negative, indicating Leptospira spp. exposure in the absence of current infection. While their status as maintenance hosts needs to be investigated further, this is the first study to show leptospiral seropositivity in red-tailed squirrels (S. granatensis).


Assuntos
Animais de Zoológico , Leptospira/isolamento & purificação , Leptospirose/veterinária , Doenças dos Primatas/microbiologia , Doenças dos Roedores/microbiologia , Sciuridae/microbiologia , Animais , Colômbia/epidemiologia , Feminino , Leptospirose/epidemiologia , Leptospirose/microbiologia , Masculino , Doenças dos Primatas/epidemiologia , Primatas , Ratos , Fatores de Risco , Doenças dos Roedores/epidemiologia
2.
PLoS Negl Trop Dis ; 14(12): e0008946, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33382723

RESUMO

Human activities can increase or decrease risks of acquiring a zoonotic disease, notably by affecting the composition and abundance of hosts. This study investigated the links between land use and infectious disease risk in northeast Madagascar, where human subsistence activities and population growth are encroaching on native habitats and the associated biota. We collected new data on pathogenic Leptospira, which are bacteria maintained in small mammal reservoirs. Transmission can occur through close contact, but most frequently through indirect contact with water contaminated by the urine of infected hosts. The probability of infection and prevalence was compared across a gradient of natural moist evergreen forest, nearby forest fragments, flooded rice and other types of agricultural fields, and in homes in a rural village. Using these data, we tested specific hypotheses for how land use alters ecological communities and influences disease transmission. The relative abundance and proportion of exotic species was highest in the anthropogenic habitats, while the relative abundance of native species was highest in the forested habitats. Prevalence of Leptospira was significantly higher in introduced compared to endemic species. Lastly, the probability of infection with Leptospira was highest in introduced small mammal species, and lower in forest fragments compared to other habitat types. Our results highlight how human land use affects the small mammal community composition and in turn disease dynamics. Introduced species likely transmit Leptospira to native species where they co-occur, and may displace the Leptospira species naturally occurring in Madagascar. The frequent spatial overlap of people and introduced species likely also has consequences for public health.


Assuntos
Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Zoonoses , Animais , Ecologia , Ecossistema , Florestas , Humanos , Espécies Introduzidas , Leptospira/genética , Leptospirose/microbiologia , Madagáscar/epidemiologia , Mamíferos , Prevalência
3.
BMC Infect Dis ; 20(1): 794, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33109122

RESUMO

BACKGROUND: Pulmonary hemorrhage is an important complication of leptospirosis. Once acute respiratory distress syndrome (ARDS) occurs as a secondary condition, treatment is extremely difficult and the mortality rate is very high. CASE PRESENTATION: The patient was a 49-year-old. He was admitted to the hospital because he had experienced a fever and cough for 4 days. Hemorrhage, respiratory failure, ARDS and other symptoms appeared soon after admission. Due to severe pulmonary hemorrhage secondary to ARDS, mechanical ventilation was performed through tracheal intubation. During intubation, the patient suffered cardiac arrest, and the patient's condition worsened. He was confirmed to have leptospirosis through second-generation sequencing of the alveolar lavage fluid. Finally, we successfully treated the patient with penicillin as an anti-infective medication and venous-venous extracorporeal membrane oxygenation (v-vECMO). To the best of our knowledge, this report is the first to describe the successful application of ECMO in mainland China. CONCLUSIONS: Leptospirosis can induce serious but transient ARDS with a better prognosis than other causes of ARDS. Our patient was successfully treated with V-vECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Hemorragia/etiologia , Hemorragia/cirurgia , Leptospira/genética , Leptospirose/complicações , /cirurgia , Antibacterianos/uso terapêutico , Líquido da Lavagem Broncoalveolar/microbiologia , China , Humanos , Leptospira/isolamento & purificação , Leptospirose/tratamento farmacológico , Leptospirose/microbiologia , Masculino , Pessoa de Meia-Idade , Penicilinas/uso terapêutico , Prognóstico , Respiração Artificial/efeitos adversos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/cirurgia , Resultado do Tratamento
4.
PLoS One ; 15(10): e0239991, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091006

RESUMO

Shedding of DNA of pathogenic Leptospira spp. has been documented in naturally infected cats in several countries, but urinary shedding of infectious Leptospira spp. has only recently been proven. The climate in Southern Chile is temperate rainy with high annual precipitations which represents ideal preconditions for survival of Leptospira spp., especially during spring and summer. The aims of this study were to investigate shedding of pathogenic Leptospira spp. in outdoor cats in Southern Chile, to perform molecular characterization of isolates growing in culture, and to assess potential risk factors associated with shedding. Urine samples of 231 outdoor cats from rural and urban areas in southern Chile were collected. Urine samples were investigated for pathogenic Leptospira spp. by 4 techniques: qPCR targeting the lipL32 gene, immunomagnetic separation (IMS)-coupled qPCR (IMS-qPCR), direct culture and IMS-coupled culture. Positive urine cultures were additionally confirmed by PCR. Multilocus sequence typing (MLST) was used to molecularly characterize isolates obtained from positive cultures. Overall, 36 urine samples (15.6%, 95% confidence interval (CI) 11.4-20.9) showed positive results. Eighteen (7.8%, 95% CI 4.9-12.1), 30 (13%, 95% CI 9.2-18), 3 (1.3%, 0.3-3.9) and 4 cats (1.7%; 95% CI 0.5-4.5) were positive in qPCR, IMS-qPCR, conventional culture, and IMS-coupled culture, respectively. MLST results of 7 culture-positive cats revealed sequences that could be assigned to sequence type 17 (6 cats) and sequence type 27 (1 cat) corresponding to L. interrogans (Pathogenic Leptospira Subgroup 1). Shedding of pathogenic Leptospira spp. by cats might be an underestimated source of infection for other species including humans. The present study is the first one reporting growth of leptospires from feline urine in culture in naturally infected cats in South-America and characterisation of culture-derived isolates. So far, very few cases of successful attempts to culture leptospires from naturally infected cats are described worldwide.


Assuntos
Derrame de Bactérias/fisiologia , Doenças do Gato/patologia , Leptospira/patogenicidade , Leptospirose/patologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Doenças do Gato/microbiologia , Doenças do Gato/transmissão , Gatos , DNA Bacteriano/metabolismo , Feminino , Leptospira/genética , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Leptospirose/transmissão , Leptospirose/veterinária , Lipoproteínas/genética , Lipoproteínas/isolamento & purificação , Masculino , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Urina/microbiologia
5.
PLoS Negl Trop Dis ; 14(9): e0008662, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32986693

RESUMO

BACKGROUND: Leptospirosis is a widespread zoonosis with global impact, particularly among vulnerable populations in resource-poor settings in tropical countries. Rodents have been considered to be the main reservoir of the disease; however, a wide variety of mammals can act as hosts as well. Here we examine the genetic diversity of Leptospira strains from biological samples of patients and animals in French Polynesia (FP) from 2011 to 2019. METHODOLOGY/PRINCIPAL FINDINGS: From 2011 to 2019, we have collected 444 blood samples from patients diagnosed as having leptospirosis. The limited volume of clinical material and low amount of leptospiral DNA in blood samples led us to develop a nested PCR targeting the secY locus that enabled us to amplify and sequence 244 samples (55%). In addition, 20 Leptospira strains recovered from the blood of patients from 2002 to 2011 were sequenced and fully characterized at the serogroup level and used as reference strains for the association of different phylogenetic branches with respective serogroups. The secY sequences were compared with publicly available sequences from patients and animal reservoirs in FP (n = 79). We identified rats as the main source of infection for L. borgpetersenii serogroup Ballum and L. interrogans serogroup Icterohaemorrhagiae, dogs as the main source of infection for L. interrogans serogroup Australis, and farm pigs as the main source of infection for L. interrogans serogroups Pomona or Canicola. L. interrogans was associated with the most severe infections with 10 and 5 fatal cases due to serogroups Icterohaemorrhagiae and Australis, respectively. Mortality was significantly associated with older age (p-value < 0.001). CONCLUSIONS/SIGNIFICANCE: We described the population dynamics of leptospires circulating among patients in FP, including two patients who were reinfected with unrelated Leptospira genotypes, and clarified the local role of the animal reservoirs in the transmission route of leptospirosis to humans. Routine Leptospira genotyping directly on biological samples should allow the epidemiological follow-up of circulating strains and assess the impact of control interventions on disease transmission.


Assuntos
Genótipo , Leptospira/genética , Leptospirose/epidemiologia , Epidemiologia Molecular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Proteínas de Bactérias/genética , Criança , DNA Bacteriano/sangue , Cães , Feminino , Seguimentos , Variação Genética , Humanos , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Leptospirose/transmissão , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Filogenia , Polinésia/epidemiologia , Ratos , Análise de Sequência de DNA , Sorogrupo , Suínos , Adulto Jovem , Zoonoses/epidemiologia
6.
PLoS One ; 15(9): e0239069, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915919

RESUMO

The diagnosis of leptospirosis remains a challenge due to its non-specific symptoms and the biphasic nature of the illness. A comprehensive diagnosis that includes both molecular (polymerase chain reaction (PCR)) and serology is vital for early detection of leptospirosis and to avoid misdiagnosis. However, not all samples could be subjected to both tests (serology and molecular) due to budget limitation, infrastructure, and technical expertise at least in resource-limited countries. We evaluated the usefulness of testing the clinically suspected leptospirosis cases with both techniques on all samples collected from the patients on the day of admission. Among the 165 patient's blood/serum samples tested (from three hospitals in Central Malaysia), 43 (26%) showed positivity by microscopic agglutination test (MAT), 63 (38%) by PCR, while 14 (8%) were positive by both MAT and PCR. For PCR, we tested two molecular targets (lipL32 by qPCR and 16S rDNA or rrs by nested PCR) and detected lipL32 in 47 (29%) and rrs gene in 63 (38%) patients. The use of more than one target gene for PCR increased the detection rates. Hence, a highly sensitive multiplex PCR targeting more than one diagnostic marker is recommended for the early detection of Leptospira in suspected patients. When the frequencies for positivity detected either by MAT or PCR combined, leptospirosis was diagnosed in a total of 92 (56%) patients, a higher frequency compared to when samples were only tested by a single method (MAT or PCR). The results from this study suggest the inclusion of both serology and molecular methods for every first sample irrespective of the days post-onset of symptoms (DPO) collected from patients for early diagnosis of leptospirosis.


Assuntos
Testes de Aglutinação , Leptospira/isolamento & purificação , Leptospirose/diagnóstico , Reação em Cadeia da Polimerase , Sepse/diagnóstico , DNA Bacteriano/isolamento & purificação , Erros de Diagnóstico/prevenção & controle , Diagnóstico Precoce , Estudos de Viabilidade , Humanos , Leptospira/genética , Leptospira/imunologia , Leptospirose/sangue , Leptospirose/imunologia , Leptospirose/microbiologia , Malásia , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Sepse/sangue , Sepse/imunologia , Sepse/microbiologia , Fatores de Tempo
7.
Ann Agric Environ Med ; 27(3): 356-360, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32955214

RESUMO

OBJECTIVES: The aim of this study is to evaluate the seroprevalence of antibodies of Borrelia burgdorferi sensu lato (Bbsl) and Leptospira interrogans sensu lato (Lisl) and their possible concurrence in domestic cats living in variable conditions in South Moravia in the district of Brno and its environs. Additional objectives were to discover possible differences in seroprevalence between groups of cats living in different living conditions, and to determine the spectrum of Leptospira serogroups in cats in the same places. MATERIAL AND METHODS: A total of 360 blood sera from domestic cats of 3 different sets were collected during the period 2013-2015. All samples were examined using ELISA for the detection of IgM and IgG antibodies against Bbsl, and the microscopic agglutination test (MAT) for the detection of antibodies against 8 serogroups of Lisl. RESULTS: The ELISA method determined 15.8%, 4.8% and 10.3% IgM anti-Borrelia antibodies in the patient group, shelter cats and street cats, respectively. IgG anti-Borrelia antibodies were found in 6.2%, 9.5%, 5.2%, respectively. Antibodies specific for 5 Leptospira serogroups were detected by the use of MAT in 8.8%, 9.5% and 10.3% of cats from the investigated groups. The total positivity of all examined cats for anti-Borrelia antibodies was 18.0% and for anti-Leptospira - 9.2%. CONCLUSIONS: Cats can be infected with both Bbsl and Lisl. The obtained results are exclusive to the city of Brno and its environs, and are comparable to the limited previous studies. There is a need for further studies of clinical signs of both infections and the possible transmission of Leptospira by ticks.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Doenças do Gato/epidemiologia , Leptospira interrogans/isolamento & purificação , Leptospirose/veterinária , Doença de Lyme/veterinária , Animais , Anticorpos Antibacterianos/sangue , Doenças do Gato/microbiologia , Gatos , República Tcheca/epidemiologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Prevalência , Estudos Soroepidemiológicos
8.
Am J Trop Med Hyg ; 103(4): 1427-1434, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32748767

RESUMO

Molecular data are required to improve our understanding of the epidemiology of leptospirosis in Africa and to identify sources of human infection. We applied molecular methods to identify the infecting Leptospira species and genotypes among patients hospitalized with fever in Tanzania and compared these with Leptospira genotypes detected among animals in Tanzania to infer potential sources of human infection. We performed lipL32 real-time PCR to detect the presence of pathogenic Leptospira in acute-phase plasma, serum, and urine samples obtained from study participants with serologically confirmed leptospirosis and participants who had died with febrile illness. Leptospira blood culture was also performed. In positive specimens, we performed species-specific PCR and compared participant Leptospira secY sequences with Leptospira reference sequences and sequences previously obtained from animals in Tanzania. We detected Leptospira DNA in four (3.6%) of 111 participant blood samples. We detected Leptospira borgpetersenii (one participant, 25.0%), Leptospira interrogans (one participant, 25.0%), and Leptospira kirschneri (one participant, 25.0%) (one [25%] undetermined). Phylogenetic comparison of secY sequence from the L. borgpetersenii and L. kirschneri genotypes detected from participants was closely related to but distinct from genotypes detected among local livestock species. Our results indicate that a diverse range of Leptospira species is causing human infection. Although our analysis suggests a close relationship between Leptospira genotypes found in people and livestock, continued efforts are needed to obtain more Leptospira genetic material from human leptospirosis cases to help prioritize Leptospira species and genotypes for control.


Assuntos
Leptospira/isolamento & purificação , Leptospirose/transmissão , Gado/microbiologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Reservatórios de Doenças , Genes Bacterianos , Técnicas de Genotipagem , Humanos , Leptospira/classificação , Leptospira/genética , Leptospirose/epidemiologia , Leptospirose/microbiologia , Lipoproteínas/genética , Patologia Molecular , Filogenia , Canais de Translocação SEC/genética , Tanzânia/epidemiologia , Zoonoses/epidemiologia
9.
Am J Trop Med Hyg ; 103(5): 1834-1837, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32748775

RESUMO

Leptospira spp. are fastidious and slow-growing bacteria, making recovery difficult and diagnostic sensitivity in the clinical setting low. However, collection of Leptospira isolates is valuable for epidemiological and laboratory research. Severe leptospirosis cases may present as septic shock, and the differential diagnosis often includes bacterial septicemia, leading clinicians to collect blood cultures. Here, we report the successful isolation of pathogenic Leptospira spp. from blood culture bottles (targeting aerobic bacteria incubated at 37°C) from a 64-year-old man admitted with septic shock. The patient presented with 4 days of fever, severe hypotension, transient atrial fibrillation, jaundice, and oliguric renal failure. After admission, intravenous ceftriaxone plus azithromycin was given with fluid resuscitation, norepinephrine infusion, invasive mechanical ventilation, and renal replacement therapy. He was discharged from the hospital 16 days after admission. Using the blood sample obtained on admission, the diagnosis of leptospirosis was confirmed by multiplex real-time PCR (targeting bacterial 16S rRNA and LipL32 gene). We collected 200 µL from the blood culture bottle to inoculate a 5-mL Ellinghausen, McCullough, Johnson, and Harris media supplemented with 5% fetal bovine serum. After 2 weeks of incubation at 30°C, Leptospira strains were identified and confirmed by real-time PCR. Genotyping was undertaken using the multi-locus sequence typing (MLST) scheme#1. The isolate matched with ST50 isolates in the PUbMLST database. This case provides evidence that in tropical countries, severe leptospirosis should be considered in patients who present with symptoms of sepsis. Pathogenic Leptospira may be successfully isolated from aerobic blood cultures in routine clinical settings.


Assuntos
Leptospira/isolamento & purificação , Leptospirose/diagnóstico , Leptospirose/microbiologia , Choque Séptico/microbiologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Azitromicina/administração & dosagem , Azitromicina/uso terapêutico , Hemocultura , Ceftriaxona/administração & dosagem , Ceftriaxona/uso terapêutico , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Choque Séptico/diagnóstico
10.
PLoS Negl Trop Dis ; 14(8): e0008573, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841248

RESUMO

BACKGROUND: Leptospirosis has gained much attention in Sri Lanka since its large outbreak in 2008. However, most of the cases were clinically diagnosed and information on Leptospira genotypes and serotypes currently prevailing in the country is lacking. METHODOLOGY/PRINCIPAL FINDINGS: We retrospectively analyzed 24 Leptospira strains from human patients as well as isolated and characterized three Leptospira strains from black rats using the microscopic agglutination test with antisera for 19 serovars and multilocus sequence typing. The isolates were identified as Leptospira borgpetersenii sequence types (STs) 143 and 144; L. interrogans STs 30, 34, 43, 44, 74, 75, 80, 308, 313, 314, 316, and 317; and L. kirschneri ST318. Six of the 15 STs were identified for the first time in this study. Five serogroups such as Autumnalis, Grippotyphosa, Hebdomadis, Javanica, and Pyrogenes were detected among the isolates. Contrary to previous studies, various genotypes including novel STs were isolated during an outbreak in Southern Province. L. borgpetersenii serogroup Javanica ST143 was isolated both from a human and black rat. CONCLUSIONS/SIGNIFICANCE: This study revealed that genetically diverse Leptospira strains currently circulate in Sri Lanka: some genotypes have been circulating and others have emerged recently, which may explain the recent surge of leptospirosis patients with varying clinical manifestations and frequent outbreaks of leptospirosis. Black rats were identified as the source of infection for humans, but reservoir animals for other genotypes remain unknown.


Assuntos
Genótipo , Leptospira/classificação , Leptospira/genética , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Tipagem de Sequências Multilocus/métodos , Adolescente , Adulto , Idoso , Testes de Aglutinação , Animais , Criança , DNA Bacteriano/análise , Reservatórios de Doenças , Feminino , Humanos , Leptospirose/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sequência de DNA , Sorogrupo , Sorotipagem , Sri Lanka/epidemiologia , Adulto Jovem
11.
PLoS Pathog ; 16(8): e1008639, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32790743

RESUMO

Leptospirosis is a worldwide re-emerging zoonosis caused by pathogenic Leptospira spp. All vertebrate species can be infected; humans are sensitive hosts whereas other species, such as rodents, may become long-term renal carrier reservoirs. Upon infection, innate immune responses are initiated by recognition of Microbial Associated Molecular Patterns (MAMPs) by Pattern Recognition Receptors (PRRs). Among MAMPs, the lipopolysaccharide (LPS) is recognized by the Toll-Like-Receptor 4 (TLR4) and activates both the MyD88-dependent pathway at the plasma membrane and the TRIF-dependent pathway after TLR4 internalization. We previously showed that leptospiral LPS is not recognized by the human-TLR4, whereas it signals through mouse-TLR4 (mTLR4), which mediates mouse resistance to acute leptospirosis. However, although resistant, mice are known to be chronically infected by leptospires. Interestingly, the leptospiral LPS has low endotoxicity in mouse cells and is an agonist of TLR2, the sensor for bacterial lipoproteins. Here, we investigated the signaling properties of the leptospiral LPS in mouse macrophages. Using confocal microscopy and flow cytometry, we showed that the LPS of L. interrogans did not induce internalization of mTLR4, unlike the LPS of Escherichia coli. Consequently, the LPS failed to induce the production of the TRIF-dependent nitric oxide and RANTES, both important antimicrobial responses. Using shorter LPS and LPS devoid of TLR2 activity, we further found this mTLR4-TRIF escape to be dependent on both the co-purifying lipoproteins and the full-length O antigen. Furthermore, our data suggest that the O antigen could alter the binding of the leptospiral LPS to the co-receptor CD14 that is essential for TLR4-TRIF activation. Overall, we describe here a novel leptospiral immune escape mechanism from mouse macrophages and hypothesize that the LPS altered signaling could contribute to the stealthiness and chronicity of the leptospires in mice.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Leptospira/imunologia , Leptospirose/imunologia , Lipopolissacarídeos/metabolismo , Lipoproteínas/metabolismo , Antígenos O/metabolismo , Receptor 4 Toll-Like/fisiologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Citocinas/metabolismo , Feminino , Leptospirose/metabolismo , Leptospirose/microbiologia , Leptospirose/patologia , Receptores de Lipopolissacarídeos/genética , Receptores de Lipopolissacarídeos/metabolismo , Lipoproteínas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/fisiologia , Antígenos O/genética , Transdução de Sinais , Receptor 2 Toll-Like/fisiologia
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(7): 1110-1114, 2020 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-32741180

RESUMO

Objective: To understand the etiological characteristics of the patients with fever of unknown origin in Guizhou province through the isolation and identification of Leptospira interrogans and provide evidence for the control, prevention and treatment of human leptospirosis. Methods: Blood and urine samples were collected from patients with fever symptoms in Qiandongnan, an epidemic area, in Guizhou. The suspected Leptospira strains were primarily identified using pathogenic Leptospira specific G1/G2-PCR, and subsequently identified by using Leptospira serogroups specific PCR. The Leptospira strains were then genotyped with multiple locus sequence typing. MLST data based cluster analysis on the isolates and Leptospira reference strains of common serogroups were analyzed by using software NTsys 2.10e. Results: Three suspected strains of Leptospira were isolated from human blood samples, the isolation rate was 8.6%, which were designated as strain 17BX002, 17BX003 and 17AJX008. Strain 17BX002 was further identified as serogroup grippotyphosa by using Leptospira serogroup specific PCR, while the other two strains were negative (excluded as iterohaemorrhagiae, sejroe, canicola, autumnalis, grippotyphosa and hebdomadis). MLST genotyping showed that strain 17BX002 was typed as ST106, most closely clustered with Leptospira grippotyphosa, while strain 17BX003 and 17AJX008 were typed as ST96, the same as serogroup badaviae. Conclusion: There are leptospirosis cases in epidemic area of Guizhou in high incidence season, grippotyphosa and bataviae are the newly discovered serogroups of Leptospira in Guizhou.


Assuntos
Febre de Causa Desconhecida/microbiologia , Leptospira interrogans/genética , Leptospira interrogans/isolamento & purificação , Leptospirose/microbiologia , Técnicas de Tipagem Bacteriana , China/epidemiologia , Humanos , Leptospirose/epidemiologia , Leptospirose/prevenção & controle , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Sorogrupo
13.
PLoS One ; 15(7): e0236007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32668449

RESUMO

Leptospirosis is a re-emerging zoonotic disease of high medical importance that affects humans worldwide. Humans or animals acquire an infection with pathogenic leptospires either by direct contact with infected animals or by indirect contact to contaminated environment. Survival of Leptospira spp. in the environment after having been shed via animal urine is thus a key factor to estimate the risk of infection, but not much is known about the tenacity of pathogenic leptospires. Here, the survival time of both a laboratory strain and a field strain of L. kirschneri serovar Grippotyphosa in animal urine and their tenacity while drying was investigated and compared at different temperatures (15°C-37°C). Leptospira spp. are also often found in rivers and ponds. As the infection risk for humans and animals also depends on the spreading and survival of Leptospira spp. in these environments, the survival of L. kirschneri serovar Grippotyphosa was investigated using a 50-meter-long hose system simulating a water stream. Both strains did not survive in undiluted cattle or dog urine. Comparing different temperatures and dilution media, the laboratory strain survived the longest in diluted cattle urine with a slightly alkaline pH value (3 days), whilst the field strain survived in diluted dog urine with a slightly acid pH value up to a maximum of 24 h. Both strains did not survive drying on a solid surface. In a water stream, leptospires were able to move faster or slower than the average velocity of the water due to their intrinsic mobility but were not able to survive the mechanical damage caused by running water in the hose system. From our results we conclude, that once excreted via animal urine, the leptospires immediately need moisture or a water body to survive and stay infectious.


Assuntos
Doenças do Cão/epidemiologia , Leptospira/crescimento & desenvolvimento , Leptospira/isolamento & purificação , Leptospirose/veterinária , Urina/microbiologia , Poluentes da Água/análise , Zoonoses/epidemiologia , Animais , Bovinos , Doenças do Cão/microbiologia , Cães , Feminino , Leptospirose/microbiologia , Doenças Transmitidas pela Água/epidemiologia , Doenças Transmitidas pela Água/microbiologia , Zoonoses/microbiologia
14.
Am J Trop Med Hyg ; 103(3): 999-1008, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32700658

RESUMO

A 1-year population-based prospective study was launched in Seychelles, a country with one of the highest human incidence of leptospirosis worldwide, to describe the characteristic features of the epidemiology of the disease and highlight the most prominent risk factors. Diagnosis was based on the IgM enzyme-linked immunosorbent assay, microscopic agglutination test, and real-time PCR. A standardized questionnaire was administered to 219 patients aged ≥ 13 years consulting for acute febrile illness. The high incidence of leptospirosis in Seychelles was confirmed. The disease was particularly severe, as the case fatality rate was 11.8%. Leptospirosis was positively associated in univariate analysis with socio-professional and clinical variables including gardening/farming, oliguria, jaundice, conjunctivitis, history of hepatitis C virus infection, anemia, thrombocytopenia, and/or biological renal failure. Epidemiological analyses of the questionnaires highlighted a link of the disease with living in houses (versus apartment), the presence of animals around and in houses, gardening, and misuse of personal protective equipment. Multivariate analyses indicated that being a farmer/landscaper and having cattle and cats around the home are the most significant drivers of leptospirosis. Biological features most associated with leptospirosis were thrombocytopenia, leukocytosis, high values for renal function tests, and elevated total bilirubin. We report changes in behavior and exposure compared with data collected on leptospirosis 25 years ago, with indication that healthcare development has lowered case fatality. Continuous health education campaigns are recommended as well as further studies to clarify the epidemiology of human leptospirosis, especially the role of domestic animals.


Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulina M/sangue , Leptospira/patogenicidade , Leptospirose/epidemiologia , Leptospirose/transmissão , Adolescente , Adulto , Idoso , Testes de Aglutinação , Animais , Gatos , Bovinos , Fazendeiros , Feminino , Humanos , Incidência , Leptospira/imunologia , Leptospirose/microbiologia , Leptospirose/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Seicheles/epidemiologia , Inquéritos e Questionários , Análise de Sobrevida
15.
PLoS Negl Trop Dis ; 14(7): e0008437, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32701971

RESUMO

BACKGROUND: Leptospirosis is one of the most significant zoonoses across the world not only because of its impact on human and animal health but also because of the economic and social impact on agrarian communities. Leptospirosis is endemic in Sri Lanka where paddy farming activities, the use of draught animals in agriculture, and peridomestic animals in urban and rural areas play important roles in maintaining the infection cycle of pathogenic Leptospira, especially concerning animals as a potential reservoir. In this study, an environmental DNA (eDNA) metabarcoding methodology was applied in two different agro-ecological regions of Sri Lanka to understand the eco-epidemiology of leptospirosis. METHODOLOGY/PRINCIPAL FINDINGS: Irrigation water samples were collected in Kandy District (wet zone mid-country region 2) and Girandurukotte, Badulla District (intermediate zone low-country region 2); and analysed for the presence of pathogenic Leptospira, associated microbiome and the potential reservoir animals. Briefly, we generated PCR products for high-throughput sequencing of multiple amplicons through next-generation sequencing. The analysis of eDNA showed different environmental microbiomes in both regions and a higher diversity of Leptospira species circulating in Kandy than in Girandurukotte. Moreover, the number of sequence reads of pathogenic Leptospira species associated with clinical cases such as L. interrogans was higher in Kandy than in Girandurukotte. Kandy also showed more animal species associated with pathogenic bacterial species than Girandurukotte. Finally, several pathogenic bacterial species including Arcobacter cryaerophilus, responsible for abortion in animals, was shown to be associated with pathogenic Leptospira. CONCLUSIONS/SIGNIFICANCE: Leptospirosis has been considered to be endemic in wet regions, consistently, leptospiral sequences were detected strongly in Kandy. The great Leptospira species diversity in Kandy observed in this study shows that the etiological agents of leptospirosis in Sri Lanka might be underestimated. Furthermore, our eDNA metabarcoding can be used to discriminate bacterial and animal species diversity in different regions and to explore environmental microbiomes to identify other associated bacterial pathogens in the environment.


Assuntos
Água Doce/microbiologia , Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Leptospirose/microbiologia , Irrigação Agrícola , Animais , DNA Bacteriano/genética , DNA Ambiental/genética , Humanos , Leptospira/classificação , Leptospira/genética , Filogenia , Sri Lanka/epidemiologia , Zoonoses/microbiologia , Zoonoses/transmissão
16.
PLoS One ; 15(6): e0233776, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502160

RESUMO

Leptospirosis is a worldwide emerging zoonotic disease caused by Leptospira species, that in some patients develop severe forms with high mortality. In France, Corsica is the area where the highest incidences have been reported. The present study was focused on the analysis of pathogenic Leptospira species in rodents of Corsica, as these micromammals are the main natural reservoirs of the bacteria, in order to identify the circulating species and to locate possible risk focuses of transmission, as no previous study on the presence of Leptospira species has been carried out in the island. Rattus rattus, Rattus norvegicus, Apodemus sylvaticus and Mus musculus domesticus were captured in the proximity of water sources along Corsica, the detection of pathogenic Leptospira species was carried out by amplification of the LipL32 gene. The bacteria were found in all the rodent species analyzed and widely. The general prevalence was 10.4%, reaching the maximum value in Bastia (45%). Leptospira interrogans and Leptospira borgpetersenii were identified by phylogenetic analysis, but also two sequences which corresponded to an unnamed Leptospira species, only previously found in rodents of New Caledonia. The high incidence of human leptospirosis in Corsica could be partially explained by the wide distribution of pathogenic Leptospira species identified in this study. Also, the presence of an unknown pathogenic species of Leptospira in an area with high prevalence, may be involved in the higher incidence of Leptospirosis in this island, however, the zoonotic capacity of this species remains unknown. The results obtained are interesting for public health since all positive samples were found near water sources and one of the routes of transmission of leptospirosis is contact with contaminated water. This information could help the competent entities to take preventive measures, reducing the incidence of human leptospirosis in Corsica.


Assuntos
Leptospira/isolamento & purificação , Murinae/microbiologia , Animais , Animais Selvagens/microbiologia , Reservatórios de Doenças/microbiologia , Feminino , França , Leptospira/classificação , Leptospirose/microbiologia , Masculino , Camundongos , Ratos
17.
Sci Rep ; 10(1): 7239, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350316

RESUMO

Leptospirosis is caused by pathogenic Leptospira transmitted through contact with contaminated environments. Most mammalian species are infectable by Leptospira but only few act as efficient reservoir being capable of establishing long term kidney colonization and shedding Leptospira in urine. In Madagascar, a large diversity of pathogenic Leptospira display a tight specificity towards their endemic volant or terrestrial mammalian hosts. The basis of this specificity is unknown: it may indicate some genetically determined compatibility between host cells and bacteria or only reflect ecological constraints preventing contacts between specific hosts. In this study, Rattus norvegicus was experimentally infected with either Leptospira interrogans, Leptospira borgpetersenii or Leptospira mayottensis isolated from rats, bats or tenrecs, respectively. Leptospira borgpetersenii and L. mayottensis do not support renal colonization as featured by no shedding of live bacteria in urine and low level and sporadic detection of Leptospira DNA in kidneys. In contrast 2 out of the 7 R. norvegicus challenged with L. interrogans developed renal colonization and intense Leptospira shedding in urine throughout the 3 months of experimental infection. These data suggest that host-Leptospira specificity in this biodiversity hotspot is driven at least in part by genetic determinants likely resulting from long-term co-diversification processes.


Assuntos
Biodiversidade , Leptospira , Leptospirose , Animais , DNA Bacteriano/metabolismo , Feminino , Rim/metabolismo , Rim/microbiologia , Rim/patologia , Leptospira/isolamento & purificação , Leptospira/metabolismo , Leptospira/patogenicidade , Leptospirose/metabolismo , Leptospirose/microbiologia , Leptospirose/patologia , Ratos , Ratos Wistar , Especificidade da Espécie
18.
J Med Microbiol ; 69(4): 587-590, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32427562

RESUMO

Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of Leptospira species. It is a public health issue in the tropics, including Okinawa, the southernmost prefecture of Japan. This study reports the first isolation of L. interrogans serogroup Sejroe from two human patients in Japan, and describes its molecular characterization using multilocus sequence typing (MLST) and multiple-locus variable-number tandem repeat analysis (MLVA). MLST on the two isolates, 168036 and 178129, showed that pfkB in 178129 is a novel allele, and that both isolates constitute novel sequence types (STs); ST286 for 168036 and ST287 for 178129. A minimum spanning tree based on seven alleles of L. interrogans indicates that both isolates are genetically close, but are distinct from known L. interrogans serogroup Sejroe strains. MLVA using 11 loci demonstrated that seven of the 11 loci were identical between the two isolates, whereas the identity between the isolates and the seven reference strains of L. interrogans serogroup Sejroe was zero to three loci. These results indicate that the isolates investigated in this study have novel genotypes, and are genetically closest to each other among the known L. interrogans serogroup Sejroe strains.


Assuntos
Leptospira interrogans/isolamento & purificação , Leptospirose/microbiologia , Genótipo , Humanos , Japão , Leptospira interrogans/classificação , Leptospira interrogans/genética , Repetições Minissatélites , Tipagem de Sequências Multilocus , Filogenia , Sorogrupo
19.
PLoS One ; 15(3): e0230048, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155209

RESUMO

Leptospirosis is one of the most widespread zoonotic diseases and can infect both humans and animals worldwide. Healthy cat, as a potential source of exposure to humans, are likely underestimated owing to the lack of overt clinical signs associated with Leptospira spp. infection in this species. The aim of the study was to determine the exposure, shedding, and carrier status of leptospires in shelter cats in Malaysia by using serological, molecular, and bacteriological methods. For this study, 82 healthy cats from two shelters were sampled. The blood, urine, and kidneys were tested using the microscopic agglutination test (MAT), polymerase chain reaction (PCR), and bacterial culture. On the basis of serological, molecular, and/or culture techniques, the total detection of leptospiral infection was 29.3% (n = 24/82). Through culture techniques, 16.7% (n = 4/24) of the cats that tested positive were carriers with positive kidney cultures, and one cat was culture positive for both urine and kidney. The Leptospira spp. isolates were identified as pathogenic L. interrogans serovar Bataviae through serological and molecular methods. Through serological techniques, 87.5% (n = 21/24) had positive antibody titers (100-1600) and most of the Bataviae serogroup (n = 19/21). Using PCR, 16.7% (n = 4/24) of cats were shown to have pathogenic Leptospira spp. DNA in their urine. Furthermore, three out of four culture positive cats were serology negative. The present study reports the first retrieval of pathogenic leptospires from urine and kidneys obtained from naturally infected cats. The results provide evidence of the potential role of naturally infected cats in the transmission of leptospires. Additionally, leptospiral infection occurs sub-clinically in cats. The culture isolation provides evidence that healthy cats could be reservoirs of leptospiral infection, and this information may promote the development of disease prevention strategies for the cat population.


Assuntos
Doenças do Gato/microbiologia , Doenças do Gato/urina , Rim/microbiologia , Leptospira/isolamento & purificação , Leptospira/fisiologia , Leptospirose/epidemiologia , Animais , Gatos , Leptospirose/microbiologia , Leptospirose/urina
20.
BMC Infect Dis ; 20(1): 186, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111168

RESUMO

BACKGROUND: The presentation of clinical leptospirosis has been historically associated with animal workers, slaughterhouse workers and medical veterinarians. This association has shifted to be related to flooding events and outdoor activities; few cases are related to high-risk factors found in immunosuppressed patients. Scarcely a handful of cases have serological evidence of immune response against Leptospira serovar Bratislava representing serogroup Australis, a serovar associated with poor reproductive performance in swine and horses, and recently with cats. CASE PRESENTATION: Herein, we describe a rare clinical presentation of disseminated Leptospira infection in an immunosuppressed 65-year-old woman. She was admitted to the emergency room with fever, bacteraemia, bilateral uveitis and pulmonary involvement. The patient denied outdoor activities; she only had wide exposure to faeces and urine from cats living in her home. Her medical history included idiopathic thrombocytopenic purpura (ITP) diagnosed at the age of 18. She did not respond to medical treatment, and a splenectomy was performed. At age 60, she was diagnosed with Chronic Myeloid Leukemia (CML), and was treated with a tyrosine kinase inhibitor (TKI) -Imatinib. The patient voluntarily discontinued the treatment for the last 6 months. After extensive workup, no microorganisms were identified by the commonly used stains in microbiology. The diagnosis was performed through dark-field microscopy, microagglutination test (MAT), Leptospira genus-specific PCR, the IS1500 PCR for identification of pathogenic species, and 16S based sequencing for the genus identification. CONCLUSION: Immunosuppressed patients may acquire uncommon infections from ubiquitous microorganisms. In this case, serology evidence of exposure to Leptospira serovar Bratislava by MAT and the presence of the Leptospira genus were identified. It should be on mind for the diagnosis in otherwise healthy patients, and thoroughly search on splenectomised patients exposed to animals. Additionally, this report highlights the usefulness of PCR for diagnosis of this potentially life-threatening illness.


Assuntos
Bacteriemia/diagnóstico , Leptospirose/diagnóstico , Idoso , Bacteriemia/microbiologia , DNA Bacteriano/metabolismo , Feminino , Humanos , Hospedeiro Imunocomprometido , Leptospira/genética , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Pneumonia por Mycoplasma/diagnóstico , Insuficiência Respiratória/diagnóstico , Esplenectomia , Tórax/diagnóstico por imagem , Uveíte/diagnóstico
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