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1.
PLoS Negl Trop Dis ; 15(12): e0009993, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34905535

RESUMO

BACKGROUND: Leptospirosis is considered an endemic disease among agricultural workers in Okinawa Prefecture, which is the southernmost part of Japan and has a subtropical climate, but data on the current status and trend of this disease are scarce. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a retrospective study of clinically suspected leptospirosis patients whose sample and information were sent to the Okinawa Prefectural Institute of Health and Environment from November 2003 to December 2020. Laboratory diagnosis was established using culture, nested polymerase chain reaction (PCR), and/or microscopic agglutination test (MAT) with blood, cerebrospinal fluid, and/or urine samples. Statistical analyses were performed to compare the epidemiological information, clinical features, and sensitivities of diagnostic methods among laboratory-confirmed cases. Serogroups and the species of Leptospira isolates were determined by MAT using 13 antisera and flaB sequencing. A total of 531 clinically suspected patients were recruited, among whom 246 (46.3%) were laboratory confirmed to have leptospirosis. Among the confirmed cases, patients aged 20-29 years (22.4%) and male patients (85.7%) were the most common. The most common estimated sources of infection were recreation (44.5%) and labor (27.8%) in rivers. Approximately half of the isolates were of the L. interrogans serogroup Hebdomadis. The main clinical symptoms were fever (97.1%), myalgia (56.3%), and conjunctival hyperemia (52.2%). Headache occurred significantly more often in patients with Hebdomadis serogroup infections than those with other serogroup infections. The sensitivities of culture and PCR exceeded 65% during the first 6 days, while the sensitivity of MAT surpassed that of culture and PCR in the second week after onset. PCR using blood samples was a preferable method for the early diagnosis of leptospirosis. CONCLUSIONS/SIGNIFICANCE: The results of this study will support clinicians in the diagnosis and treatment of undifferentiated febrile patients in Okinawa Prefecture as well as patients returning from Okinawa Prefecture.


Assuntos
Leptospira/patogenicidade , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Academias e Institutos , Adulto , Conjuntivite/epidemiologia , Conjuntivite/microbiologia , Doenças Endêmicas , Feminino , Febre/epidemiologia , Febre/microbiologia , Cefaleia/epidemiologia , Cefaleia/microbiologia , Humanos , Japão/epidemiologia , Leptospira/classificação , Leptospira/genética , Leptospira/imunologia , Leptospirose/fisiopatologia , Masculino , Mialgia/epidemiologia , Mialgia/microbiologia , Estudos Retrospectivos , Sorogrupo , Adulto Jovem
2.
PLoS Negl Trop Dis ; 15(8): e0009670, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34403427

RESUMO

BACKGROUND: Fever with jaundice is a common symptom of some infectious diseases. In public health surveillance within the Democratic Republic of the Congo (DRC), yellow fever is the only recognized cause of fever with jaundice. However, only 5% of the surveillance cases are positive for yellow fever and thus indicate the involvement of other pathogens. Leptospira spp. are the causative agents of leptospirosis, a widespread bacterial zoonosis, a known cause of fever with jaundice. This study aimed to determine the seropositivity of anti-Leptospira antibodies among suspected yellow fever cases and map the geographical distribution of possible leptospirosis in the DRC. METHODS: We conducted a retrospective study using 1,300 samples from yellow fever surveillance in the DRC from January 2017 to December 2018. Serum samples were screened for the presence of IgM against Leptospira spp. by a whole cell-based IgM ELISA (Patoc-IgM ELISA) at the Institut National de Recherche Biomedicale in Kinshasa (INRB) according to World Health Organization (WHO) guidance. Exploratory univariable and multivariable logistic regression analyses were undertaken to assess associations between socio-demographic factors and the presence of Leptospira IgM. RESULTS: Of the 1,300 serum samples screened, 88 (7%) showed evidence of IgM against Leptospira spp. Most positive cases (34%) were young adult males in the 20-29-year group. There were statistically significant associations between having Leptospira IgM antibodies, age, sex, and living area. Observed positive cases were mostly located in urban settings, and the majority lived in the province of Kinshasa. There was a statistically significant association between seasonality and IgM Leptospira spp. positivity amongst those living in Kinshasa, where most of the positive cases occurred during the rainy season. CONCLUSIONS: This study showed that leptospirosis is likely an overlooked cause of unexplained cases of fever with jaundice in the DRC and highlights the need to consider leptospirosis in the differential diagnosis of fever with jaundice, particularly in young adult males. Further studies are needed to identify animal reservoirs, associated risk factors, and the burden of human leptospirosis in the DRC.


Assuntos
Febre/diagnóstico , Febre/epidemiologia , Febre/microbiologia , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Adolescente , Adulto , Animais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , República Democrática do Congo/epidemiologia , Humanos , Imunoglobulina M/sangue , Lactente , Recém-Nascido , Icterícia/diagnóstico , Icterícia/epidemiologia , Icterícia/microbiologia , Leptospira/imunologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Febre Amarela/diagnóstico , Febre Amarela/epidemiologia , Febre Amarela/microbiologia , Adulto Jovem
3.
BMC Vet Res ; 17(1): 221, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154583

RESUMO

BACKGROUND: Leptospirosis is an endemic zoonosis in Brazil, with a great impact on human and animal health. Although dogs are frequently infected by pathogenic Leptospira, the current epidemiological understanding of canine leptospirosis is mainly based on serological tests that predict the infecting serogroup/serovar. Thus, the present study aimed at identifying the causative agent for severe cases of canine leptospirosis in a highly endemic area through the isolation and characterization of the isolated strains. RESULTS: Urine, serum and blood samples were collected from 31 dogs with suspected acute leptospirosis treated at the Veterinary Hospital Service of Santo Amaro University between 2018 and 2019. Acute infection was confirmed in 17 dogs (54.8%) by the associated use of Polymerase Chain Reaction (PCR), Microscopic Agglutination (MAT) and bacteriological culture. Eleven dogs (35.5%) had titers ≥800, with the most frequent serogroups being Autumnalis and Icterohaemorrhagiae (n = 4 each) and Canicola (n = 2). Leptospires were recovered from four dogs, and Multilocus Sequence Analysis (MLSA) revealed infection caused by L. interrogans, which were further characterized as serogroups Canicola (n = 1) and Icterohaemorrhagiae (n = 3). CONCLUSION: The identity of the isolates and serological pattern of MAT suggest that dogs are highly exposed to the serogroup Icterohaemorrhagiae and Canicola, also indicating possible circulation of serogroups not yet isolated in Brazil, notably serogroup Autumnalis. Our findings also reinforce the usefulness of using multiple diagnostic approaches to confirm acute canine leptospirosis.


Assuntos
Doenças do Cão/diagnóstico , Leptospira/isolamento & purificação , Leptospirose/veterinária , Testes de Aglutinação/veterinária , Animais , Brasil , Doenças do Cão/microbiologia , Cães , Leptospira/classificação , Leptospira/genética , Leptospira/imunologia , Leptospira interrogans/isolamento & purificação , Leptospirose/diagnóstico , Leptospirose/microbiologia , Tipagem de Sequências Multilocus/veterinária , Reação em Cadeia da Polimerase/veterinária , Sorogrupo
4.
Sci Rep ; 11(1): 10365, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33990653

RESUMO

Leptospirosis is a zoonosis caused by pathogenic Leptospira spp. Cats have been reported to be infected with Leptospira spp. and shed the bacteria in the urine. However, the importance of cats as an infection source for humans remains unclear. In this study, Leptospira infection in cats in Okinawa Prefecture, Japan, where leptospirosis is endemic, was investigated by leptospiral antibody and DNA detection using microscopic agglutination test and nested PCR, respectively. Moreover, multilocus sequence typing (MLST) and whole genome sequencing (WGS) were conducted on the Leptospira borgpetersenii serogroup Javanica isolated from cats, black rats, a mongoose, and humans. Anti-Leptospira antibodies were detected in 16.6% (40/241) of the cats tested, and the predominant reactive serogroup was Javanica. The leptospiral flaB gene was detected in 7.1% (3/42) of cat urine samples, and their sequences were identical and identified as L. borgpetersenii. MLST and WGS revealed the genetic relatedness of L. borgpetersenii serogroup Javanica isolates. This study indicated that most seropositive cats had antibodies against the serogroup Javanica and that cats excreted L. borgpetersenii in the urine after infection. Further, genetic relatedness between cat and human isolates suggests that cats may be a maintenance host for L. borgpetersenii serogroup Javanica and a source for human infection.


Assuntos
Doenças do Gato/microbiologia , Leptospira/genética , Leptospirose/veterinária , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Gatos , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Japão/epidemiologia , Leptospira/imunologia , Leptospira/isolamento & purificação , Leptospirose/sangue , Leptospirose/epidemiologia , Leptospirose/microbiologia , Masculino , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Sequenciamento Completo do Genoma
5.
mSphere ; 6(2)2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762318

RESUMO

This study examined the humoral and cellular response of cattle vaccinated with two commercial leptospiral vaccines, Leptavoid and Spirovac, and a novel bacterin vaccine using Seppic Montanide oil emulsion adjuvant. Vaccination was followed by experimental challenge. All vaccinated cattle were protected from colonization of the kidney and shedding of Leptospira in urine, as detected by culture and immunofluorescence assay. Agglutinating antibody titers were detected in vaccinated cattle at 4 weeks following vaccination, with small anamnestic response detected following experimental challenge. Only animals vaccinated with the oil emulsion-adjuvanted bacterin produced significant IgG2 titers following vaccination, and nonvaccinated animals produced serum IgA titers after experimental challenge. CD4+ and γδ T cells from vaccinated cattle proliferated when cultured with antigen ex vivo Cellular responses included a marked proliferation of γδ T cells immediately following experimental challenge in vaccinated cattle and release of gamma interferon (IFN-γ), interleukin 17a (IL-17a), and IL-12p40 from stimulated cells. Proliferative and cytokine responses were found not just in peripheral mononuclear cells but also in lymphocytes isolated from renal lymph nodes at 10 weeks following experimental challenge. Overall, effects of leptospirosis vaccination and infection were subtle, resulting in only modest activation of CD4+ and γδ T cells. The use of Seppic Montanide oil emulsion adjuvants may shorten the initiation of response to vaccination, which could be useful during outbreaks or in areas where leptospirosis is endemic.IMPORTANCE Leptospirosis is an underdiagnosed, underreported zoonotic disease of which domestic livestock can be carriers. As a reservoir host for Leptospira borgpetersenii serovar Hardjo, cattle may present with reproductive issues, including abortion, birth of weak or infected calves, or failure to breed. Despite years of study and the availability of commercial vaccines, detailed analysis of the bovine immune response to vaccination and Leptospira challenge is lacking. This study evaluated immunologic responses to two efficacious commercial vaccines and a novel bacterin vaccine using an adjuvant chosen for enhanced cellular immune responses. Antigen-specific responsive CD4 and γδ T cells were detected following vaccination and were associated with release of inflammatory cytokines IFN-γ and IL-17a after stimulation. CD4 and γδ cells increased in the first week after infection and, combined with serum antibody, may play a role in clearance of bacteria from the blood and resident tissues. Additionally, these antigen-reactive T cells were found in the regional lymph nodes following infection, indicating that memory responses may not be circulating but are still present in regional lymph nodes. The information gained in this study expands knowledge of bovine immune response to leptospirosis vaccines and infection. The use of oil emulsion adjuvants may enhance early immune responses to leptospiral bacterins, which could be useful in outbreaks or situations where leptospirosis is endemic.


Assuntos
Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Doenças dos Bovinos/prevenção & controle , Leptospira/imunologia , Leptospirose/prevenção & controle , Leptospirose/veterinária , Vacinação/veterinária , Animais , Vacinas Bacterianas/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Citocinas/imunologia , Feminino , Imunidade Celular , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Interferon gama/análise , Interferon gama/imunologia , Linfócitos Intraepiteliais/imunologia , Leptospira/classificação , Leptospirose/imunologia , Sorogrupo
6.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 277-284, Mar.-Apr. 2021. tab, mapas
Artigo em Inglês | ID: biblio-1248945

RESUMO

Bovine leptospirosis assumes great economic importance since it affects several production aspects. Therefore, knowledge about the occurrence and distribution of this disease is fundamental to adopt the correct prevention measures. The present study aimed to evaluate the frequency of anti-Leptospira spp. antibodies in 24,483 bovine serum samples received between 2007 to 2015 from 21 Brazilian states. Of these, 8,643 (35.3%) were reagents in the microscopic agglutination test to one or more serovars of Leptospira spp. The most frequent serovars were Wolffi (61.47%), Tarassovi (9.62%) and Pomona (7.20%). Hardjo serovar presented a prevalence of 6.27%. Among the 21 states analyzed, the State of Pernambuco had the highest frequency with 88.24% and the State of São Paulo was the origin of the largest number of analyzed samples (13,838), with a frequency of 31.54% of reagents. The results demonstrate a high exposure to several serovars of Leptospira spp. in bovine species in Brazilian states, showing the importance of adopting prophylactic measures in order to reduce the risk of infection in this specie.(AU)


Com o objetivo de avaliar a frequência de anticorpos anti-Leptospira spp., foram analisadas 24.483 amostras de soro sanguíneo bovino, provenientes de 21 estados brasileiros, recebidas no período de 2007 a 2015. Destas, 8.643 (35,3%) foram reagentes no teste de soroaglutinação microscópica a uma ou mais sorovariedades de Leptospira spp., e as sorovariedades com maior frequência foram Wolffi (61,47%), Tarassovi (9,62%) e Pomona (7,20%). A sorovariedade Hardjo apresentou prevalência de 6,27%. Entre os 21 estados analisados, o estado de Pernambuco apresentou a maior frequência, com 88,24%, e o estado de São Paulo foi a origem do maior número de amostras para análise, 13.838, com frequência de 31,54% de reagentes.(AU)


Assuntos
Animais , Bovinos , Cobertura Vacinal/estatística & dados numéricos , Leptospira/imunologia , Leptospirose/veterinária , Leptospirose/epidemiologia , Brasil/epidemiologia , Testes de Hemaglutinação/veterinária
7.
Braz J Microbiol ; 52(2): 1013-1019, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33580866

RESUMO

Leptospirosis is a neglected zoonotic disease of unknown magnitude that has been overlooked and underreported, influenced by complex interactions established among humans, animals, and the environment; certain occupations, such as working with livestock, have an increased risk of exposure. We conducted a cross trans-sectional study in 374 serum samples obtained from workers and residents of dairy farms in the Tizayuca Basin, Hidalgo, Mexico, to determine the prevalence of anti-Leptospira antibody and the risk factors associated to this type of environment. The determination of anti-Leptospira antibodies was obtained by microscopic agglutination test. Seropositivity was defined from titles > 1:100. Seropositivity of anti-Leptospira antibodies among the population was 46.8% (176/374) (95% Cl 41.9-52.1). Thirty-nine percent (146/74) of the analyzed serum reacted to the Hardjo serovar (Sejröe serogroup). Eighty-eight percent (8/9) slaughterhouse workers tested were seropositive. Those who belonged to an ethnic group had OR 1.78 (IC 1.02-3.11, P = 0.041). Seropositivity was associated with having a secondary school level or lower, with OR 1.79 (IC 0.97-3.29, P = 0.058). Exposure to Leptospira in a dairy production farm is a risk factor for humans. Our findings can contribute to strengthening the intervention of the Public Health System to prevent this zoonosis that prevails in dairy farm environments.


Assuntos
Indústria de Laticínios/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Fazendas/estatística & dados numéricos , Leptospira/patogenicidade , Leptospirose/epidemiologia , Adulto , Animais , Anticorpos Antibacterianos/sangue , Estudos Transversais , Feminino , Humanos , Leptospira/imunologia , Leptospirose/sangue , Leptospirose/microbiologia , Leptospirose/transmissão , Masculino , México/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Sorogrupo , Zoonoses/sangue , Zoonoses/epidemiologia , Zoonoses/microbiologia , Zoonoses/transmissão
8.
J Wildl Dis ; 57(1): 60-70, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33635986

RESUMO

The warthog (Phacochoerus africanus) can be used as a model for investigating disease transmission at the human, wildlife, and livestock interface. An omnivore and scavenger, a warthog moves freely between natural ecotypes, farmland, and human communities and is susceptible to diseases of zoonotic, agricultural, and conservation concern. A retrospective study using 100 individual serum samples collected from May 1999 to August 2016 was performed to determine antibody prevalence to seven pathogens in warthogs from five locations in northeastern South Africa. Higher prevalence of antibodies to African swine fever virus and Mycobacterium bovis were detected in warthogs from the Greater Kruger National Park ecosystem in comparison to lower prevalence of antibodies to M. bovis and no antibodies to African swine fever virus in warthogs from uMhkuze Game Reserve. Low prevalence of antibodies to foot-and-mouth disease virus, Rift Valley fever virus, and influenza A virus was detected in all locations, and no antibodies against Brucella and Leptospira spp. were detected. No statistically significant difference in antibody prevalence was found between sexes for any disease. At the univariate analysis, M. bovis seropositivity was significantly different among age categories, with 49% (35/71) of adults found positive versus 29% (4/14) of juveniles and 9% (1/11) of sub-adults (Fisher's exact test, P=0.020), and between the sampling locations (Fisher's exact test, P=0.001). The multivariate model results indicated that juvenile warthogs had lower odds of testing positive to M. bovis antibodies than adults (juveniles' odds ratio [OR]=0.17, 95% confidence interval [CI]: 0.02-1.0), although this result was not statistically significant at the 5% level (P=0.052). For warthogs sampled at Satara Buffalo Camp, the odds (OR=0.22, 95% CI: 0.035-0.96) of being M. bovis antibody positive were significantly lower (P=0.043) than for warthogs sampled at Skukuza. Of particular interest in this study was the detection of warthogs seropositive for influenza A virus.


Assuntos
Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Bactérias/imunologia , Suínos/sangue , Vírus/imunologia , Vírus da Febre Suína Africana , Animais , Brucella/imunologia , Vírus da Febre Aftosa/imunologia , Vírus da Influenza A/imunologia , Leptospira/imunologia , Mycobacterium bovis , Vírus da Febre do Vale do Rift/imunologia , África do Sul/epidemiologia , Suínos/imunologia
9.
Comp Immunol Microbiol Infect Dis ; 75: 101609, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33493976

RESUMO

Leptospirosis is a zoonotic disease with worldwide endemicity in Argentina, it is a significant public health problem in low-income populations. Bovine leptospirosis is a serious economic problem for cattle production, causing abortions, reduced milk yield, mortality in calves and decreased daily weight gain. We developed an enzyme-linked immunosorbent assay (ELISA) with sonicated Leptospira interrogans serogroup Icterohaemorrhagiae serovar Copenhageni M 20. We evaluated its performance for the detection of specific antibodies against multiple Leptospira serogroups in bovine. The microscopic agglutination test (MAT) was used as the gold standard. The performance of this ELISA was evaluated with a panel of sera (118 MAT confirmed positive and 97 MAT negative). The overall sensitivity was close to 85.6 % and the specificity was 83.5 %, according to the MAT reference method. Analytical specificity of the IgG-ELISA was evaluated using 50 bovine serum samples from animals showing serum antibodies against other pathogens that cause abortion in bovine, such as Brucella sp., Neospora sp. and Bovine Viral Diarrhea (BVD), and no cross-reaction was observed. This IgG-ELISA can be an alternative to the MAT for diagnosis of leptospiral infection in bovine.


Assuntos
Doenças dos Bovinos , Leptospira , Leptospirose , Testes de Aglutinação/veterinária , Animais , Anticorpos Antibacterianos , Argentina , Bovinos , Doenças dos Bovinos/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leptospira/imunologia , Leptospirose/diagnóstico , Leptospirose/veterinária , Gravidez , Sorogrupo
10.
Sci Rep ; 11(1): 1064, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441663

RESUMO

Leptospirosis is an overlooked zoonotic disease caused by pathogenic Leptospira depended on virulence of Leptospira and the host-pathogen interaction. Kidney is the major organ infected by Leptospira which causes tubulointerstitial nephritis. Leptospira outer membrane contains several virulence factors and an outer membrane protein A (OmpA) like protein (Loa22) is essential for virulence. Pull-down assays suggested that Loa22 was a potential Toll-Like Receptor 2 (TLR2) binding candidates from pathogenic Leptospira. Confocal microscopy was employed to observe the co-localization of TLR2 and Loa22-LPGN (Leptospira peptidoglycan) complexes. Atomic force microscopy (AFM), side-directed mutagenesis, and enzyme-linked immunosorbent assay (ELISA) were performed to investigate the affinity between rLoa22, LPGN, and TLR2. Real time PCR was applied to measure the cytokines expression. Downstream signal transduction components were verified by western blot to evaluate the gene regulations. Mutation of two Loa22 key residues (Asp122 and Arg143) attenuated the affinities for LPGN. rLoa22-LPGN complexes were observed to co-localize with TLR2 and provoked inflammatory responses including CXCL8/IL8, hCCL2/MCP-1, and hTNF-α. Affinity studies suggested that Loa22-LPGN complexes elevated the affinity to TLR2 as compared to Loa22 protein. Downstream signals from TLR2 including p38, ERK, and JNK were regulated under rLoa22-LPGN complexes treatments. This study identified LPGN mediates interactions between Loa22 and TLR2 and induces downstream signals to trigger inflammatory responses. rLoa22-LPGN-TLR2 complexes reveal a novel binding mechanism for the innate immune system.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Imunidade Inata , Leptospira/metabolismo , Leptospirose/imunologia , Peptidoglicano/metabolismo , Receptor 2 Toll-Like/metabolismo , Proteínas da Membrana Bacteriana Externa/imunologia , Células HEK293 , Humanos , Inflamação/imunologia , Inflamação/parasitologia , Leptospira/imunologia , Leptospirose/metabolismo , Microscopia Confocal , Reação em Cadeia da Polimerase em Tempo Real
11.
Braz J Microbiol ; 52(2): 953-960, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33483895

RESUMO

The epidemiological behavior of six Leptospira serovarieties was analyzed by spatial autocorrelation and co-occurrence of leptospirosis, diagnosed in goat herds located in the State of Guanajuato, Mexico. A total of 1650 goat serum samples were analyzed by microscopic agglutination (MAT). True prevalence (Pv) and 95% confidence interval (CI95) were determined. Spatial autocorrelation was calculated using the spdep package, applying the global Moran's I and local Moran's I of Leptospira in Guanajuato. The probabilistic model of co-occurrence was applied using the co-occur package. Seroprevalence in the State was found to be 45.5% (CI95 42.96; 48.06%). The highest registered frequency was for the Icterohemorrhagiae serovar (Pv 34.16%; CI95 31.74, 36.65%), followed by the serovar Hardjo-prajitno (Pv: 6.77%; CI95 5.33, 8.40%). Other serovarieties showed a Pv < 5%. Global spatial autocorrelation, only for the Icterohemorrhagiae serovar, was I > 1, while local Moran's I revealed that five of the six Leptospira serovarieties were spatially correlated. The probabilistic model of co-occurrence detected negative associations between Icterohemorrhagiae and the other serovarieties. The current study demonstrates the presence of Leptospira in goat herds of the State of Guanajuato. The diagnosed serovarieties show an aggregation pattern associated to risk zones and disease-transmitting vectors. Antibody co-occurrence analysis revealed dominance of the Icterohemorrhagiae serovar. A multidisciplinary approach including spatial epidemiology, ecological analyses, and serological vigilance will generate useful information for the prevention and control of leptospirosis in caprine production units.


Assuntos
Coinfecção/veterinária , Doenças das Cabras/microbiologia , Leptospira/isolamento & purificação , Leptospirose/veterinária , Animais , Anticorpos Antibacterianos/sangue , Coinfecção/epidemiologia , Coinfecção/microbiologia , Doenças das Cabras/epidemiologia , Cabras , Leptospira/classificação , Leptospira/imunologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , México/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Sorogrupo , Análise Espacial
12.
J Vet Diagn Invest ; 33(1): 52-58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33084527

RESUMO

Clinical manifestations of leptospirosis are diverse and very similar to other febrile diseases, hence early and accurate detection of subclinical infections is a key element in disease control. We evaluated immunomagnetic separation (IMS) capture technology coupled with a standard quantitative PCR (qPCR) system for the detection of pathogenic Leptospira in urine samples from 803 cows from dairy herds with a history of clinical cases of leptospirosis. The urine samples were first processed in a purification step, then subdivided into 2 subsamples, one that continued to DNA extraction and direct qPCR, and one that was pretreated by IMS before continuing to DNA extraction and qPCR. Overall, 133 of 803 (16.6%) samples were IMS-qPCR positive, whereas only 92 of 803 (11.5%) were positive when using direct qPCR. Statistically significant differences were observed between the mean estimated Leptospira load between the IMS-qPCR and the direct qPCR positive urine samples. The IMS-qPCR technology revealed a larger number of positive results and higher bacterial loads than direct qPCR. This difference is most likely the result of the high antigen-binding capacity and capture efficiency of the IMS system. The use of polyclonal antibodies produced by the inoculation of 3 synthetic peptides, which make up the extracellular regions of the LipL32 protein, provided a high detection capacity to the IMS-qPCR technique, resulting in performance superior to direct qPCR.


Assuntos
Criação de Animais Domésticos , Doenças dos Bovinos/diagnóstico , Leptospira/isolamento & purificação , Leptospirose/veterinária , Animais , Bovinos , Doenças dos Bovinos/urina , Chile , Indústria de Laticínios , Feminino , Separação Imunomagnética/veterinária , Leptospira/genética , Leptospira/imunologia , Leptospirose/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sensibilidade e Especificidade , Urinálise/veterinária
13.
Int J Biol Macromol ; 168: 289-300, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33310091

RESUMO

Leptospirosis is a potentially fatal zoonosis that is caused by spirochete Leptospira. The signs and symptoms of leptospirosis are usually varied, allowing it to be mistaken for other causes of acute febrile syndromes. Thus, early diagnosis and identification of a specific agent in clinical samples is crucial for effective treatment. This study was aimed to develop specific monoclonal antibodies against LipL21 antigen for future use in leptospirosis rapid and accurate immunoassay. A recombinant LipL21 (rLipL21) antigen was optimized for expression and evaluated for immunogenicity. Then, a naïve phage antibody library was utilized to identify single chain fragment variable (scFv) clones against the rLipL21 antigen. A total of 47 clones were analysed through monoclonal phage ELISA. However, after taking into consideration the background OD405 values, only 4 clones were sent for sequencing to determine human germline sequences. The sequence analysis showed that all 4 clones are identical. The in silico analysis of scFv-lip-1 complex indicated that the charged residues of scFv CDRs are responsible for the recognition with rLipL21 epitopes. The generated monoclonal antibody against rLipL21 will be evaluated as a detection reagent for the diagnosis of human leptospirosis in a future study.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Técnicas de Visualização da Superfície Celular/métodos , Leptospira/imunologia , Lipoproteínas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Proteínas da Membrana Bacteriana Externa/metabolismo , Bacteriófagos/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos/imunologia , Humanos , Imunoensaio/métodos , Leptospira/metabolismo , Leptospira interrogans/genética , Leptospirose/diagnóstico , Lipoproteínas/isolamento & purificação , Lipoproteínas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes/genética , Anticorpos de Cadeia Única/imunologia
14.
Curr Protoc Microbiol ; 59(1): e127, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33141517

RESUMO

Leptospirosis is a zoonotic disease caused by pathogenic Leptospira species that are maintained in sylvatic and domestic environments by transmission among rodents and other carriers. Humans become infected after contact of breached skin or mucosa with contaminated water or soil. Understanding persistent or sublethal infection in a host is critical for controlling human risk of exposure to pathogenic Leptospira. Animal models that recapitulate disease progression after infection via natural transmission routes are more appropriate for validation of vaccines and therapeutics. Furthermore, the ability to measure shedding of live Leptospira in urine of reservoir and carrier hosts can be used to develop new diagnostic assays and sensors to evaluate human risk of exposure. We developed inbred mouse models of Leptospirosis, that bypass survival as a criterion, in which we can analyze both pathogen and host factors affecting sublethal infection (<1 month), including shedding of Leptospira in urine. Mice are infected with pathogenic Leptospira using a physiologic route, and the clinical, histological, and molecular scores of disease are measured. Furthermore, the host immune response to Leptospira is evaluated. This mouse model also provides a tool in which to test fundamental hypotheses related to host-pathogen interactions and the immune mechanisms engaged in protective and pathogenic immune responses. © 2020 Wiley Periodicals LLC Basic Protocol 1: Culture and maintenance of virulent Leptospira Basic Protocol 2: Infection of mice through a physiologic route and collection of clinical scores and biological samples Basic Protocol 3: Analysis of pathogenesis after Leptospira infection.


Assuntos
Imunidade , Leptospira/imunologia , Leptospirose/imunologia , Leptospirose/transmissão , Animais , Técnicas Bacteriológicas/métodos , Técnicas de Laboratório Clínico/métodos , Cricetinae , Modelos Animais de Doenças , Feminino , Leptospirose/microbiologia , Masculino , Camundongos , Zoonoses
15.
Front Immunol ; 11: 568694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193344

RESUMO

Leptospirosis is a zoonotic disease of worldwide distribution, affecting both humans and animals. The development of an effective vaccine against leptospirosis has long been pursued but without success. Humans are contaminated after direct contact with the urine of infected animals or indirectly by contaminated water or soil. The vaccines available consist of inactivated whole-bacterial cells, and the active immunoprotective antigen is the lipopolysaccharide moiety, which is also the basis for serovar classification. However, these vaccines are short-lasting, and protection is only against serovars contained in the preparation. The search for prevalent antigens, present in pathogenic species of Leptospira, represents the most cost-effective strategy for prevention of leptospirosis. Thus, the identification of these antigens is a priority. In this study, we examined the immunoprotective effect of eight leptospiral recombinant proteins using hamster as the challenge model. Animals received subcutaneously two doses of vaccine containing 50 µg of each recombinant protein adsorbed on alum adjuvant. Two weeks after the booster, animals were challenged with virulent leptospires and monitored for 21 days. All proteins were able to induce a specific immune response, although significant protective effects on survival rate were observed only for the proteins Lsa14, rLIC13259, and rLIC11711. Of these, only rLIC13259 and rLIC11711 were found to be highly prospective in promoting renal clearance. The sterilizing potential of both proteins will be further investigated to elucidate the immunoprotective mechanisms involved in leptospirosis control. These are the first proteins involved with human complement components with the capacity to protect against virulent challenge and to eliminate the bacteria from the host.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/farmacologia , Leptospira/imunologia , Leptospirose/prevenção & controle , Doença Aguda , Adjuvantes Imunológicos/farmacologia , Compostos de Alúmen/farmacologia , Animais , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Cricetinae , Modelos Animais de Doenças , Masculino , Proteínas Recombinantes/farmacologia
16.
Trop Anim Health Prod ; 52(6): 3789-3798, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33009586

RESUMO

Leptospirosis is an important economical disease of livestock globally, especially in Asia, the Caribbean, and the African continent. Its presence has been reported in a wide range of livestock. However, information on leptospirosis in South Africa is scanty. We conducted a cross-sectional study in 11 randomly selected abattoirs to determine the seroprevalence and risk factors for leptospirosis in slaughtered cattle in Gauteng province, South Africa. During abattoir visits to selected abattoirs, blood samples were collected from 199 cattle and demographic data obtained on the slaughtered animals. The microscopic agglutination test (MAT) was performed on all sera using a 26-serotype panel using cutoff titer ≥ 1:100. Animal- and abattoir-level risk factors were investigated for their association with seropositivity for leptospirosis. The seroprevalence of leptospirosis in the cattle sampled was 27.6% (55/199). The predominant serogroups detected in seropositive cattle were Sejroe (sv. Hardjo) (38.2%) and Mini sv. Szwajizak) (14.5%) but low to Canicola (sv. Canicola) (1.8%) and Pomona (sv. Pomona) (1.8%). The differences were statistically significant (P < 0.05). Of the five variables investigated, only one (abattoirs) had statistically significantly (P < 0.001) differences in the seroprevalence of leptospirosis among abattoirs. The study documented for the first time in South Africa, the occurrence of serogroups Sejroe (Hardjo bovis strain lely 607), Tarassovi, Hebdomadis, and Medanensis in slaughtered cattle. It was concluded that six of the nine serovars (representing seven serogroups) of Leptospira spp. circulating in cattle population in South Africa are not vaccine serogroups. The clinical, diagnostic, and public health importance of the findings cannot be ignored.


Assuntos
Doenças dos Bovinos/epidemiologia , Leptospirose/veterinária , Matadouros , Testes de Aglutinação/veterinária , Animais , Bovinos , Estudos Transversais , Leptospira/imunologia , Leptospirose/epidemiologia , Leptospirose/microbiologia , Fatores de Risco , Estudos Soroepidemiológicos , Sorogrupo , África do Sul/epidemiologia
17.
Mol Biotechnol ; 62(11-12): 598-610, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33006126

RESUMO

The expressed recombinant leptospiral surface adhesion lipoprotein (Lsa27) of pathogenic Leptospira in E. coli was evaluated for the detection of Leptospira antibodies in cattle sera by latex agglutination test (LAT). The Lsa27 lacking signal peptide coding gene sequences from L. interrogans serovar Pomona was amplified (~ 660 bp) by PCR and the amplicon was cloned into pETiteN-HisKan vector. The expressed recombinant Lsa27 histidine-tagged fusion protein (rLsa27) was Ni-NTA affinity purified under denaturation followed by renaturation methods. The purified rLsa27 was characterized by SDS-PAGE and immunoblot, which confirmed the leptospiral protein with a MW of ~ 25 kDa. Further, the prepared sensitized latex beads coated with rLsa27 were evaluated as a diagnostic antigen for detection of pathogenic Leptospira antibodies by using known microscopic agglutination test (MAT) positive (n = 74) and negative (n = 62) sera for Leptospira antibodies in LAT, which revealed the relative diagnostic sensitivity of 91.89% and specificity of 87.10% against the gold standard serological test, MAT. Furthermore, on evaluation of developed rLsa27 LAT using serum samples from cattle associated with the history of abortions and reproductive disorder (n = 309), the relative sensitivity of 96.15%, and specificity of 89.11% were observed. Therefore, this rapid field test using the rLsa27 is first of its kind and it could be used as a screening test for the detection of Leptospira antibodies or it can be complemented by other diagnostics for the diagnosis /surveillance of bovine leptospirosis.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/microbiologia , Escherichia coli/crescimento & desenvolvimento , Leptospira/imunologia , Leptospirose/diagnóstico , Lipoproteínas/genética , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/imunologia , Clonagem Molecular , Diagnóstico Precoce , Escherichia coli/genética , Testes de Fixação do Látex , Leptospira/genética , Leptospirose/sangue , Leptospirose/imunologia , Lipoproteínas/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
18.
Comp Immunol Microbiol Infect Dis ; 73: 101552, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33035771

RESUMO

Leptospirosis in horses is often associated with reproductive disorders. In the southern states of Brazil, horses are used for various jobs and cultural practices; nevertheless, serological surveillance for Leptospira is rare. Therefore, the objective of this study was to determine the seroprevalence of Leptospira spp. in horses in southern Brazil, as well as to identify the risk factors for infection and its impacts on reproduction. We performed microscopic agglutination tests for 12 serovars that corresponding 9 serogroup (Sejroe, Icterohaemorrhagiae, Australis, Pyrogenes, Pomona, Canicola, Grippotyphosa, Tarassovi and Ballum) in 595 samples from 60 herds. A brief history was obtained to analyze risk factors for reproductive disorders. A total of 45.9% of the tested horses were seropositive, of which the most frequent serogroups were Icterohaemorrhagiae (Icterohaemorrhagiae and Copenhageni serovars) and Ballum (Ballum serovar). Simple infections were found in 45.4% of seropositive animals, while mixed infections occurred in 54.6% of horses. There was a correlation between seropositivity and age and sex, that is, seropositivity was more frequent in animals over 6 years old and in females. There was no correlation between seropositivity and reproductive disorders. We conclude that there is a high seroprevalence of Leptospira spp. in southern Brazil with predominance of Icterohaemorrhagiae serogroup, mainly in older animals. Location, breeds, contact with dogs or other domestic animals are not risk factors, whereas gender is a risk factor. Reproductive disorders are not due to leptospirosis in the study region.


Assuntos
Doenças dos Cavalos/epidemiologia , Leptospira/imunologia , Leptospirose/veterinária , Reprodução , Fatores Etários , Testes de Aglutinação/veterinária , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , Cães , Feminino , Doenças dos Cavalos/microbiologia , Doenças dos Cavalos/fisiopatologia , Cavalos , Leptospirose/epidemiologia , Leptospirose/fisiopatologia , Masculino , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/microbiologia , Complicações Infecciosas na Gravidez/fisiopatologia , Complicações Infecciosas na Gravidez/veterinária , Prevalência , Fatores de Risco , Ruminantes , Estudos Soroepidemiológicos
19.
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
20.
Comp Immunol Microbiol Infect Dis ; 73: 101546, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32916553

RESUMO

In susceptible hosts, protection from Leptospira infection is mediated by the innate immune response at the point of entry and humoral immunity. Thus, identifying and segregating the initial host response at the representative host-pathogen interface is needed to understand the typical outcomes of Leptospira infection, clearance, persistence, or disease. An in vitro whole blood culture system to study the overall immune response using pathogenic and non-pathogenic Leptospira strains was explored in this study. Using an ELISA, increased IL-8, TNF alpha, and IL-1 in blood samples stimulated with pathogenic and nonpathogenic Leptospira compared to unstimulated controls were detected. In RT2 Profiler PCR Array assays, consistent upregulation of 22 genes and downregulation of 25 genes were observed. Few of the notable upregulated genes included BPI, CCL3, CXCL2, IL-6, IL-8, TLR1, TLR2, TLR6, and TNF and downregulated genes included, LBP, LYZ, MPO, MYD88. IFNß was upregulated in samples treated with pathogenic Leptospira and IL-1ß was upregulated in samples treated with nonpathogenic Leptospira. Toll- like Receptor signaling and expression of pattern recognition receptors were two of the five prominent canonical pathways observed. Individual deconvolution of each of the specific and significant pathways observed in this study may improve the understanding of the pathogenesis of this important zoonotic agent. The use of this system in conjunction with whole transcriptome analysis in a larger population, may unveil the robust nature of host/Leptospira interaction.


Assuntos
Hemocultura/veterinária , Doenças do Cão/imunologia , Leptospira/imunologia , Leptospirose/veterinária , Animais , Hemocultura/métodos , Doenças do Cão/microbiologia , Cães , Imunidade Inata , Leptospirose/imunologia , Leptospirose/microbiologia , Receptores Toll-Like/genética
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