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1.
Emerg Infect Dis ; 30(8): 1514-1522, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043385

RESUMO

Leptospirosis is a common but underdiagnosed zoonosis. We conducted a 1-year prospective study in La Guaira State, Venezuela, analyzing 71 hospitalized patients who had possible leptospirosis and sampling local rodents and dairy cows. Leptospira rrs gene PCR test results were positive in blood or urine samples from 37/71 patients. Leptospira spp. were isolated from cultured blood or urine samples of 36/71 patients; 29 had L. interrogans, 3 L. noguchii, and 4 L. venezuelensis. Conjunctival suffusion was the most distinguishing clinical sign, many patients had liver involvement, and 8/30 patients with L. interrogans infections died. The Leptospira spp. found in humans were also isolated from local rodents; L. interrogans and L. venezuelensis were isolated from cows on a nearby, rodent-infested farm. Phylogenetic clustering of L. venezuelensis isolates suggested a recently expanded outbreak strain spread by rodents. Increased awareness of leptospirosis prevalence and rapid diagnostic tests are needed to improve patient outcomes.


Assuntos
Surtos de Doenças , Leptospira , Leptospirose , Filogenia , Roedores , Animais , Leptospirose/epidemiologia , Leptospirose/veterinária , Leptospirose/microbiologia , Leptospirose/diagnóstico , Humanos , Venezuela/epidemiologia , Bovinos , Leptospira/genética , Leptospira/isolamento & purificação , Leptospira/classificação , Feminino , Roedores/microbiologia , Adulto , Masculino , Pessoa de Meia-Idade , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/epidemiologia , Adolescente , Leptospira interrogans/genética , Leptospira interrogans/isolamento & purificação , Leptospira interrogans/classificação , Adulto Jovem , Estudos Prospectivos , Criança , Idoso , Doenças Endêmicas , Zoonoses/epidemiologia , Zoonoses/microbiologia , Pré-Escolar
2.
PLoS Negl Trop Dis ; 18(7): e0012286, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38959260

RESUMO

BACKGROUND: Habitat modification and land use changes impact ecological interactions and alter the relationships between humans and nature. Mexico has experienced significant landscape modifications at the local and regional scales, with negative effects on forest cover and biological biodiversity, especially in the Yucatan peninsula in southeastern Mexico. Given the close relationship between landscape modification and the transmission of zoonotic and vector-borne diseases, it is essential to develop criteria for identifying priority zoonoses in the south of the country. METHODOLOGY/PRINCIPAL FINDINGS: We reviewed 165 published studies on zoonotic and vector-borne diseases in the region (2015-2024). We identified the most frequent vectors, reservoirs, and hosts, the most prevalent infections, and the factors associated with transmission risk and the anthropogenic landscape modification in urban, rural, ecotone, and sylvatic habitats. The most relevant pathogens of zoonotic risk included Trypanosoma cruzi, arboviruses, Leishmania, Rickettsia, Leptospira, and Toxoplasma gondii. Trypanosoma cruzi was the vector-borne agent with the largest number of infected vertebrate species across habitats, while Leishmania and arboviruses were the ones that affected the greatest number of people. Dogs, cats, backyard animals, and their hematophagous ectoparasites are the most likely species maintaining the transmission cycles in human settlements, while rodents, opossums, bats, and other synanthropic animals facilitate connection and transmission cycles between forested habitats with human-modified landscapes. Pathogens displayed different prevalences between the landscapes, T. cruzi, arbovirus, and Leptospira infections were the most prevalent in urban and rural settlements, whereas Leishmania and Rickettsia had similar prevalence across habitats, likely due to the diversity and abundance of the infected vectors involved. The prevalence of T. gondii and Leptospira spp. may reflect poor hygiene conditions. Additionally, results suggest that prevalence of zoonotic and vector-borne diseases is higher in deforested areas and agricultural aggregates, and in sites with precarious health and infrastructure services. CONCLUSIONS: Some hosts, vectors, and transmission trends of zoonotic and vector-borne diseases in the YP are well known but others remain poorly recognized. It is imperative to reinforce practices aimed at increasing the knowledge, monitoring, prevention, and control of these diseases at the regional level. We also emphasize the need to perform studies on a larger spatio-temporal scale under the socio-ecosystem perspective, to better elucidate the interactions between pathogens, hosts, vectors, environment, and sociocultural and economic aspects in this and many other tropical regions.


Assuntos
Doenças Transmitidas por Vetores , Zoonoses , Animais , Humanos , Zoonoses/transmissão , Zoonoses/epidemiologia , Doenças Transmitidas por Vetores/transmissão , Doenças Transmitidas por Vetores/epidemiologia , Prevalência , México/epidemiologia , Ecossistema , Trypanosoma cruzi/isolamento & purificação , Vetores de Doenças , Reservatórios de Doenças/microbiologia , Leptospira/isolamento & purificação , Leptospira/genética , Leptospira/classificação , Doença de Chagas/transmissão , Doença de Chagas/epidemiologia , Toxoplasma , Arbovírus/fisiologia , Leishmania/isolamento & purificação , Leishmaniose/transmissão , Leishmaniose/epidemiologia
3.
PLoS Negl Trop Dis ; 18(5): e0011292, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38758957

RESUMO

BACKGROUND: Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate the demographic, socioeconomic and environmental factors associated with seropositivity of Leptospira serogroup Icterohaemorraghiae and serogroup Cynopteri in an urban high transmission setting for leptospirosis in Brazil. METHODS/PRINCIPAL FINDINGS: We performed a cross-sectional serological study in five informal urban communities in the city of Salvador, Brazil. During the years 2018, 2020 2021, we recruited 2.808 residents and collected blood samples for serological analysis using microagglutination assays. We used a fixed-effect multinomial logistic regression model to identify risk factors associated with seropositivity for each serogroup. Seropositivity to Cynopteri increased with each year of age (OR 1.03; 95% CI 1.01-1.06) and was higher in those living in houses with unplastered walls (exposed brick) (OR 1.68; 95% CI 1.09-2.59) and where cats were present near the household (OR 2.00; 95% CI 1.03-3.88). Seropositivity to Icterohaemorrhagiae also increased with each year of age (OR 1.02; 95% CI 1.01-1.03) and was higher in males (OR 1.51; 95% CI 1.09-2.10), in those with work-related exposures (OR 1.71; 95% CI 1.10-2.66) or who had contact with sewage (OR 1.42; 95% CI 1.00-2.03). Spatial analysis showed differences in distribution of seropositivity to serogroups Icterohaemorrhagiae and Cynopteri within the five districts where study communities were situated. CONCLUSIONS/SIGNIFICANCE: Our data suggest distinct epidemiological patterns associated with the Icterohaemorrhagiae and Cynopteri serogroups in the urban environment at high risk for leptospirosis and with differences in spatial niches. We emphasize the need for studies that accurately identify the different pathogenic serogroups that circulate and infect residents of low-income areas.


Assuntos
Leptospira interrogans , Leptospira , Leptospirose , Sorogrupo , Leptospirose/epidemiologia , Leptospirose/microbiologia , Leptospirose/transmissão , Brasil/epidemiologia , Humanos , Masculino , Adulto , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Leptospira/classificação , Leptospira/imunologia , Leptospira/isolamento & purificação , Adulto Jovem , Adolescente , Leptospira interrogans/imunologia , Leptospira interrogans/classificação , Leptospira interrogans/isolamento & purificação , Fatores de Risco , Estudos Soroepidemiológicos , População Urbana , Anticorpos Antibacterianos/sangue , Animais , Criança , Idoso
4.
Acta Trop ; 256: 107242, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38782111

RESUMO

Leptospirosis is an infectious disease with a worldwide distribution, which represents a major challenge in animal production across developing countries, mainly in tropical areas. Horses are particularly susceptible to the disease, presenting manifestations ranging from subclinical to the development of uveitis that compromises the visual health of the animals. In recent years, serological studies have been carried out in equid populations from America, demonstrating high exposure. For this reason, the aim of this study was to demonstrate microbiologically and molecularly the presence of the members of the genus Leptospira in urine samples from equids in an endemic state of leptospirosis in Mexico, and to detect the serological presence of anti-Leptospira antibodies in the sampled animals. For this reason, blood and urine samples were collected from 28 horses and one mule from three localities in the state of Veracruz, Mexico. Urine samples were inoculated in Ellinghausen-McCullough-Johnson-Harris (EMJH) medium, and the recovered isolates were typed using a short Multi Locus Sequence Typing scheme. Amplifications of the expected size were subjected to sequencing, and the recovered sequences were compared with those of reference deposited in GenBank using the BLAST tool. To identify their phylogenetic position, we performed a phylogenetic reconstruction using the maximum likelihood method. Additionally, Microscopic Agglutination test was performed on the serum samples to identify anti-Leptospira antibodies. We recovered 16 urine isolates which tested positive for the presence of Leptospira DNA. The phylogenetic reconstruction and the MLST analysis confirmed the presence of several genotypes of Leptospira interrogans and Leptospira santarosai. An overall serological frequency of 97.1 % was detected. Our results represent the first record of the presence of Leptospira through bacteriological isolates in equids from Mexico.


Assuntos
Anticorpos Antibacterianos , Doenças dos Cavalos , Leptospira , Leptospirose , Filogenia , Animais , Leptospirose/veterinária , Leptospirose/microbiologia , Leptospirose/epidemiologia , México/epidemiologia , Cavalos/microbiologia , Doenças dos Cavalos/microbiologia , Leptospira/isolamento & purificação , Leptospira/genética , Leptospira/classificação , Anticorpos Antibacterianos/sangue , Leptospira interrogans/isolamento & purificação , Leptospira interrogans/genética , Leptospira interrogans/classificação , Tipagem de Sequências Multilocus , Análise de Sequência de DNA , DNA Bacteriano/genética
5.
Braz J Microbiol ; 55(2): 1941-1948, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38691328

RESUMO

Leptospira spp. are bacteria responsible for leptospirosis, a zoonotic disease with considerable impacts on the economy, animal health, and public health. This disease has a global distribution and is particularly prevalent in Brazil. Both rural and urban environments are habitats for Leptospira spp., which are primarily transmitted through contact with the urine of infected animals. Consequently, domestic and wild species can harbor these prokaryotes and serve as infection sources for other hosts. In the context of wild animals, there is a dearth of molecular studies elucidating the roles of various animal and bacterial species in the epidemiology of leptospirosis. Therefore, this study aimed to evaluate the presence of Leptospira spp. DNA in different species of free-living and captive wild animals and to assess the phylogenetic relationships of the identified microorganisms in Rio Grande do Sul, Brazil. The samples were evaluated for the presence of the gene lipL32 by polymerase chain reaction (PCR) and sequencing of the amplified fragment after which phylogenetic analyzes were carried out. DNA from Leptospira spp. was extracted from kidney tissue from wild animals (Mammalia class). Pathogenic Leptospira spp. DNA was detected in 9.6% (11/114) of the samples, originating from nine species of wild animals, including the white-eared opossum (Didelphis albiventris), skunk (Conepatus chinga), geoffroy's cat (Leopardus geoffroyi), margay (Leopardus wiedii), pampas fox (Lycalopex gymnocercus), capybara (Hydrochoerus hydrochaeris), common marmoset (Callithrix jacchus), neotropical river otter (Lontra longicaudis), and european hare (Lepus europaeus). Phylogenetic analysis revealed the presence of Leptospira borgpetersenii and Leptospira interrogans in these animals. This research is the first study contributing to the epidemiology of leptospirosis by identifying L. borgpetersenii and L. interrogans in free-living and captive wild animals in Rio Grande do Sul, Brazil, potentially acting as bacterial reservoirs. Additionally, our findings can inform sanitary measures for controlling and preventing the disease, thereby safeguarding public health.


Assuntos
Animais Selvagens , Leptospira interrogans , Leptospira , Leptospirose , Filogenia , Animais , Brasil/epidemiologia , Leptospirose/microbiologia , Leptospirose/veterinária , Leptospirose/epidemiologia , Animais Selvagens/microbiologia , Leptospira/genética , Leptospira/isolamento & purificação , Leptospira/classificação , Leptospira interrogans/genética , Leptospira interrogans/classificação , Leptospira interrogans/isolamento & purificação , Mamíferos/microbiologia , DNA Bacteriano/genética
6.
Zoonoses Public Health ; 71(5): 457-468, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38509439

RESUMO

INTRODUCTION: Bats are a diverse group of mammals that have unique features allowing them to act as reservoir hosts for several zoonotic pathogens such as Leptospira. Leptospires have been classified into pathogenic, intermediate, and saprophytic groups and more recently into clades P1, P2, S1, and S2, being all the most important pathogenic species related to leptospirosis included within the P1/pathogenic clade. Leptospira has been detected from bats in several regions worldwide; however, the diversity of leptospires harboured by bats is still unknown. AIM: The aim of the present study was to determine the genetic diversity of Leptospira spp. harboured by bats worldwide. METHODS: A systematic review was conducted on four databases to retrieve studies in which Leptospira was detected from bats. All studies were screened to retrieve all available Leptospira spp. 16S rRNA sequences from the GenBank database and data regarding their origin. Sequences obtained were compared with each other and reference sequences of Leptospira species and analysed through phylogenetic analysis. RESULTS: A total of 418 Leptospira spp. 16S rRNA sequences isolated from 55 bat species from 14 countries were retrieved from 15 selected manuscripts. From these, 417 sequences clustered within the P1/pathogenic group, and only one sequence clustered within the P2/intermediate group. Six major clades of P1/pathogenic Leptospira spp. were identified, three of them composed exclusively of sequences obtained from bats. CONCLUSION: We identified that bats harbour a great genetic diversity of Leptospira spp. that form part of the P1/pathogenic clade, some of which are closely related to leptospirosis-associated species. This finding contributes to the knowledge of the diversity of leptospires hosted by bats worldwide and reinforces the role of bats as reservoirs of P1/pathogenic Leptospira spp.


Assuntos
Quirópteros , Variação Genética , Leptospira , Leptospirose , Filogenia , Animais , Quirópteros/microbiologia , Leptospira/genética , Leptospira/classificação , Leptospira/isolamento & purificação , Leptospirose/veterinária , Leptospirose/microbiologia , Leptospirose/epidemiologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/microbiologia , RNA Ribossômico 16S/genética , Zoonoses
7.
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
8.
BMC Microbiol ; 21(1): 17, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413126

RESUMO

BACKGROUND: Leptospira are shed into the environment via urine of infected animals. Rivers are thought to be an important risk factor for transmission to humans, though much is unknown about the types of environment or characteristics that favor survival. To address this, we screened for Leptospira DNA in two rivers in rural Ecuador where Leptospirosis is endemic. RESULTS: We collected 112 longitudinal samples and recorded pH, temperature, river depth, precipitation, and dissolved oxygen. We also performed a series of three experiments designed to provide insight into Leptospira presence in the soil. In the first soil experiment, we characterized prevalence and co-occurrence of Leptospira with other bacterial taxa in the soil at dispersed sites along the rivers (n = 64). In the second soil experiment, we collected 24 river samples and 48 soil samples at three points along eight transects to compare the likelihood of finding Leptospira in the river and on the shore at different distances from the river. In a third experiment, we tested whether Leptospira presence is associated with soil moisture by collecting 25 soil samples from two different sites. In our river experiment, we found pathogenic Leptospira in only 4 (3.7%) of samples. In contrast, pathogenic Leptospira species were found in 22% of shore soil at dispersed sites, 16.7% of soil samples (compared to 4.2% of river samples) in the transects, and 40% of soil samples to test for associations with soil moisture. CONCLUSIONS: Our data are limited to two sites in a highly endemic area, but the scarcity of Leptospira DNA in the river is not consistent with the widespread contention of the importance of river water for leptospirosis transmission. While Leptospira may be shed directly into the river, onto the shores, or washed into the river from more remote sites, massive dilution and limited persistence in rivers may reduce the environmental load and therefore, the epidemiological significance of such sources. It is also possible that transmission may occur more frequently on shores where people are liable to be barefoot. Molecular studies that further explore the role of rivers and water bodies in the epidemiology of leptospirosis are needed.


Assuntos
Leptospira/classificação , Leptospirose/epidemiologia , Rios/microbiologia , Análise de Sequência de DNA/métodos , Solo/química , Animais , DNA Bacteriano , DNA Ribossômico/genética , Equador , Doenças Endêmicas , Humanos , Leptospira/genética , Leptospira/isolamento & purificação , Filogenia , Prevalência , RNA Ribossômico 16S/genética , População Rural , Microbiologia do Solo
9.
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
10.
Comp Immunol Microbiol Infect Dis ; 73: 101560, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33099254

RESUMO

Leptospirosis has been investigated in several species of wild animals. The white-eared opossum (Didelphis albiventris) is a mammal common in the brazilian semi-arid, so, this study aimed to investigate its role in the occurrence of the leptospirosis in the region Northeast of Brazil. 12 animals were used, from which samples were collected for the attempt of isolation, molecular detection and serological examination. There was no microbial growth, nor were any anti-Leptospira sp. antibodies found in the serological samples. The PCR detected leptospiric DNA in the central nervous system (CNS) of five animals (41.7 %). The gene in one of the samples was sequenced and showed identity with Leptospira interrogans. The presence of Leptospira sp. in the CNS of Didelphis albiventris does not allow the characterization of the studied animals as reservoirs with potential for transmission of the pathogen in the region, however it represents a site that needs to be further investigated.


Assuntos
Portador Sadio/veterinária , Sistema Nervoso Central/parasitologia , Didelphis/parasitologia , Leptospira/classificação , Leptospirose/veterinária , Animais , Brasil/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/parasitologia , Leptospira/genética , Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Leptospirose/parasitologia , Filogenia , Alinhamento de Sequência/veterinária
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