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BackgroundLeptospirosis is an endemic zoonosis in Brazil, with a great impact on human and animal health. Although dogs are frequently infected by pathogenicLeptospira, 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.ResultsUrine, 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 byL. interrogans, which were further characterized as serogroups Canicola (n = 1) and Icterohaemorrhagiae (n = 3).ConclusionThe 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.

Leptospirosis is a worldwide distributed zoonosis that affects most mammal species, including dogs and humans. Vaccination is the main strategy to control disease and urinary shedding of leptospires in dogs; however, there are few studies in the literature reporting the efficacy of commercially available vaccines.To access and compare the efficacy of commercially available leptospiral vaccines dogs using a quali-quantitative systematic review.The main outcome of interest was the ability to protect dogs against clinical disease and renal carrier state, as well as promoting duration of immunity. Experimental and observational study designs were eligible for inclusion, and methodology was validated by PROSPERO, under registration CRD42020178194. Five electronic databases were searched. Data about population, methodology and outcomes were extracted in a dichotomous or continuous manner. Evaluation of risk of bias for individual studies was assessed using SYRCLE tool.Thirteen challenge trials and eight observational studies were included, comprising 12 vaccine brands. In the calculated pooled effect, vaccinated dogs had a reduced Relative Risk of developing clinical disease (0.16) and renal carrier state (0.12) when compared to unvaccinated controls. The heterogeneity between studies was low; however, methodologies and different parameters were used in the studies to define the outcomes.Our study has demonstrated that commercially available vaccines against leptospirosis can provide an overall 84% protection against clinical disease and 88% against renal carrier status. Protection against clinical disease and carrier status by serovars Canicola, Australis and Grippotyphosa is inconsistent for some vaccine brands, and such hurdle is mostly attributed to methodological difficulties in inducing experimental infection using these serovars. Evidence shows that immunity provided by the vaccines included in our meta-analysis can persist for at least one year under experimental conditions. However, the duration of MAT titers induced by vaccination do not correlate with protection.

Leptospirosis has been widely reported in insular environments worldwide, characterizing a major public health threat. Although low-genetic biodiversity is expected in these regions, the introduction of domestic and synanthropic mammals may contribute to the wider diversity of leptospiral strains in insular settings. This study proposes a large-scale seroepidemiological investigation of Leptospira infection in animals from Fernando de Noronha archipelago and describes the characterization of the first leptospiral strain ever isolated from an insular setting in Brazil. A total of 1,265 blood samples from domestic (n = 682), synanthropic (n = 133) and wild (n = 450) animals were collected between 2007 and 2014, totalling 12 species. The presence of anti-Leptospira spp. antibodies was investigated by the microscopic agglutination test (MAT), and kidney samples from 20 synanthropic rodents were collected for the isolation of Leptospira spp. The leptospires recovered were further characterized by serogrouping with polyclonal antibodies, whole-genome sequencing and multilocus sequence typing (MLST). The MAT results revealed the presence of agglutinins in 90 samples (7.1%) and the most frequently found serogroup was Icterohaemorrhagiae (n = 57) in practically all species included. Viable leptospires were recovered from one brown rat, and characterization revealed that the isolate belongs to L. interrogans serogroup Pyrogenes. The results suggest that synanthropic rodents might play an important role in leptospiral infection among wildlife and domestic species in the archipelago.

Leptospirosis has been widely reported in insular environments worldwide, characterizing a major public health threat. Although low genetic biodiversity is expected in these regions, the introduction of domestic and synanthropic mammals may contribute to the wider diversity leptospiral strains in insular settings. This study proposes a large-scale investigation of Leptospira infection in animals from Fernando de Noronha archipelago, Brazil. A total of 1,265 blood samples from domestic (n=682), synanthropic (n=133) and wild (n=450) animals were collected between 2007 and 2014, totaling 12 species. The presence of anti-Leptospira spp. antibodies was investigated by the Microscopic Agglutination Test (MAT) and kidney samples from synanthropic rodents were collected for the isolation of Leptospira spp. The leptospires recovered were further characterized by MAT with polyclonal antibodies, whole genome sequencing and Multilocus Sequence Typing (MLST). The MAT results revealed the presence of agglutinins in 90 samples (7.1%), and the most frequently found serogroup was Icterohaemorrhagiae (n=57) in practically all species included. Viable leptospires were recovered from one brown rat, and characterization revealed that the isolate belongs to L. interrogans serogroup Pyrogenes. This study stands as the most comprehensive investigation of Leptospira spp. infection in Fernando de Noronha archipelago, also providing the characterization of the first leptospiral strain ever isolated from an insular setting in Brazil. The results suggest that synanthropic rodents play a major role in the transmission of leptospirosis among wildlife and domestic species in the archipelago.

A modified TaqMan real-time polymerase chain reaction targeting a 138 bp fragment within the lipl32 gene was developed to identify exclusively pathogenic Leptospira spp. in dog urine samples. Thirty-five samples from dogs with suspected clinical leptospirosis and 116 samples from apparently healthy dogs were tested for presence of leptospiral DNA using the TaqMan-based assay. The results were compared with those from a well-established conventional PCR targeting the 16S RNA encoding gene associated with nucleotide sequencing analysis. The overall agreement between the assays was 94.8% (confidence interval [CI] 95% 88–100%). The newly developed assay presented 91.6% (CI 95% 71.5–98.5%) relative sensitivity (22[+] lipl32 PCR/24[+] 16S RNA and sequencing), 100% (CI 95% 96.3–100%) relative specificity and 98.7% accuracy (CI 95% 94.8–100%). The lipl32 assay was able to detect and quantify at least 10 genome equivalents/reaction. DNA extracted from 17 pathogenic Leptospira spp., 8 intermediate/saprophytic strains and 21 different pathogenic microorganisms were also tested using the lipl32 assay, resulting in amplification exclusively for pathogenic leptospiral strains. The results also demonstrated high intra and inter-assay reproducibility (coefficient of variation 1.50 and 1.12, respectively), thereby qualifying the newly developed assay as a highly sensitive, specific and reliable diagnostic tool for leptospiral infection in dogs using urine specimens.

Background Dogs presenting with acute leptospirosis may present non-specific clinical and laboratory findings, and the definitive diagnosis may require additional confirmatory tests, including bacterial culture, for the direct or indirect identification of the pathogen. The present study describes the diagnosis of leptospirosis in suspected dogs based on the use of multiple diagnostic tests, including serological, molecular and bacteriological tests, along with the characterization of the recovered leptospiral strains. Results Urine, serum and blood samples were collected from 33 dogs with suspected clinical leptospirosis treated at the University of São Paulo Veterinary Hospital Service (Hovet FMVZ-USP) between 2013 and 2016. Only dogs with high blood urea nitrogen and creatinine levels in association with multiple clinical manifestations of the disease were included. Leptospiral culture, PCR and serology (Microscopic agglutination test - MAT) were performed in blood and urine samples taken from all suspected dogs at clinical presentation, and an additional prospective MAT titration was performed in seven dogs. Infection could be identified exclusively by PCR in 10 dogs (30.3%), exclusively by MAT in four dogs (12.1%) and by both tests in four dogs, totaling 18 dogs (54.5–95%CI: 37.6–71.5). Six out of eight MAT-confirmed cases presented with the highest titers against the Icterohaemorrhagiae serogroup. Leptospires were recovered from urine samples from two PCR-positive dogs, and both strains could be characterized by Multilocus Sequence Analysis and serogrouping as L. interrogans serogroup Icterohaemorrhagiae. Both isolates were shown to be pathogenic in the hamster model. Conclusions The simultaneous use of MAT and PCR was able to increase the diagnosis of leptospirosis in clinically suspected cases. Despite the increasing incidence of new serovars affecting dogs being reported in different locations, our results suggest that leptospiral strains belonging to the Icterohaemorrhagiae serogroup are still a major causative agent of canine leptospirosis in São Paulo, Brazil. Electronic supplementary material The online version of this article (10.1186/s12917-018-1547-4) contains supplementary material, which is available to authorized users.

Background Lack of providers in surgery, anesthesia, and obstetrics (SAO) is a primary driver of limited surgical capacity worldwide. We aimed to identify predictors of entry into Surgery, Anesthesia, and Obstetrics and Gynecology (SAO) fields and preference of working in the public sector in Brazil which may help in profiling medical students for recruitment into these needed areas. Methods A questionnaire was applied to all Brazilian medical graduates registered with a Board of Medicine from 2014 to 2015. Twenty-three characteristics were analyzed. Logistic regression was used to determine predictors’ influence on outcome. Results There were 4601 (28.2%) responders to the survey, of which 40.5% (CI 34.7–46.5%) plan to enter SAO careers. Of the 23 characteristics analyzed, eight differed significantly between those who planned to work in SAO and those who did not. Of those eight characteristics, just three were significant predictors in the regression model: preference for working in the hospital setting, having spent more than 70% of their clinical years in practical activities, and valuing the substantial earning potential. These three factors explained only 6.3% of the variance in SAO preference. Within the graduates who preferred SAO careers, there were only two predictors for working in the public sector (“preparatory time before medical school” and valuing “prestige/status”). Conclusions Factors affecting specialty and sector choice are multifaceted and difficult to predict. Future programs to fill provider gaps should identify methods other than medical student profiling to assure specialty and sector needs are met. Electronic supplementary material The online version of this article (10.1186/s12909-019-1562-6) contains supplementary material, which is available to authorized users.

Canine leptospirosis is often caused by Leptospira interrogans serovar Canicola. Infected dogs may become asymptomatic carriers of the pathogen, which leads to many public health concerns. In this work, we present the complete genome sequencing and in silico analysis from a virulent Brazilian strain of L. interrogans serovar Canicola, previously isolated from a stray dog in Sao Paulo City. Comparative genomic analysis with a reference genome allowed identification of 1031 INDELs and several arrangement variations. Out of 35,361 SNPs identified, 6780 were missense mutations and 16,114 were synonymous mutations. The Gene Ontology terms more affected by mutations were described. Interestingly, phylogenetic analyses indicated a genetic relatedness of the isolate with serovar Linhai strain 56,609. In addition, we found several virulence-related genes and main outer membrane proteins associated with pathogenesis. This genomic information about canine isolates may help to elucidate the molecular diversity and mechanisms of Leptospira spp. pathogenicity.

Dogs are highly susceptible to the leptospiral infection, notably stray and sheltered dogs. Unsanitary conditions often observed in dog shelters may predispose the introduction and spread of leptospires among sheltered populations, potentially increasing the chances for the inadvertent adoption of asymptomatically infected animals. The present work describes a longitudinal study using a multidisciplinary approach for the identification of chronically infected dogs and the characterization of potentially pathogenic strains circulating among stray and sheltered dog populations in São Paulo, Brazil. A total of 123 dogs from three populations were included. The initial evaluation consisted of blood and urine quantitative PCR testing (qPCR), the detection of specific antibodies by microscopic agglutination test (MAT), physical examination and hematological and serum biochemistry analyses. The qPCR-positive dogs were prospectively examined, and reevaluations also included culture from urine samples. Positive qPCR samples were subjected to 16S rRNA and secY gene phylogenetic analysis. The recovered strains were characterized by Multilocus Sequence Typing, polyclonal serogroup identification and virulence determination. Leptospiruria was detected in all populations studied (13/123), and phylogenetic analysis revealed that 10 dogs had L. interrogans infection. Three dogs (3/13) had L. santarosai infection. The secY phylogenetic analysis revealed that the L. santarosai sequences clustered separately from those obtained from other hosts. Ten leptospiruric dogs were reevaluated, and three dogs presented persistent leptospiruria, allowing culturing from two dogs. The strains were characterized as L. interrogans serogroup Canicola (virulent) and L. santarosai serogroup Sejroe (not virulent). Serum samples were retested by MAT using the DU92 and DU114 strains as antigens, and no increased seroreactivity was detected. Asymptomatic L. santarosai infection was observed in all populations studied, suggesting a possible role of dogs in the chain of transmission of this leptospiral species. The results suggest a genetic distinction between lineages of Brazilian L. santarosai maintained by dogs and other animal hosts. Our findings revealed that dogs could act as maintenance hosts for distinct pathogenic Leptospira, highlighting also that asymptomatically infected dogs can be inadvertently admitted and adopted in dog shelters, potentially increasing the risks of zoonotic transmission.

The world currently faces severe biodiversity losses caused by anthropogenic activities such as deforestation, pollution, the introduction of exotic species, habitat fragmentation, and climate changes. Disease ecology in altered environments is still poorly understood. The golden-headed lion tamarin (GHLT, Leontopithecus chrysomelas) is an endangered species that became invasive in an urban park in Niteroi, Rio de Janeiro, Brazil. The initially few invasive GHLT individuals became hundreds, adapted to living in proximity to humans and domestic animals. These GHLTs were captured as part of a conservation project; some animals were translocated to Bahia and some were kept in captivity. This study tested 593 GHLT for Leptospira serology; 100 and 95 GHLT for polymerase chain reaction (PCR) toLeptospira and hepatitis E virus genotype 3 (HEV-3), respectively, and 101 familiar groups for PCR to viruses (rotavirus A, norovirus GI and GII, and HEV-3). One animal had antibodies for Leptospira serovar Shermani and another for serovar Hebdomadis. One saprophyticLeptospira was found by the 16S PCR and sequencing. Viruses were not detected in samples tested. Findings suggest that the epidemiological importance of such pathogens in this GHLT population is either low or nonexistent. These data are important to understand the local disease ecology, as well as monitoring a translocation project, and to contribute data for species conservation.

ObjectiveIn many countries an increase in the number of women in medicine is accompanied by gender inequality in various aspects of professional practice. Women in medical workforce usually earn less than their male counterparts. The aim of this study was to describe the gender wage difference and analyse the associated factors in relation to Brazil’s physicians.Participants2400 physicians.SettingNationwide, cross-sectional study conducted in 2014.MethodsData were collected via a telephone enquiry. Sociodemographic and work characteristics were considered factors, and monthly wages (only the monthly earnings based on a medical profession) were considered as the primary outcome. A hierarchical multiple regression model was used to study the factors related to wage differences between male and female physicians. The adjustment of different models was verified by indicators of residual deviance and the Akaike information criterion. Analysis of variance was used to verify the equality hypothesis subsequently among the different models.ResultsThe probability of men receiving the highest monthly wage range is higher than women for all factors. Almost 80% of women are concentrated in the three lowest wage categories, while 51% of men are in the three highest categories. Among physicians working between 20 and 40 hours a week, only 2.7% of women reported receiving >US$10 762 per month, compared with 13% of men. After adjustment for work characteristics in the hierarchical multiple regression model, the gender variable estimations (ß) remained, with no significant modifications. The final effect of this full model suggests that the probability of men receiving the highest salary level (≥US$10 762) is 17.1%, and for women it is 4.1%. Results indicate that a significant gender wage difference exists in Brazil.ConclusionThe inequality between sexes persisted even after adjusting for working factors such as weekly workload, number of weekly on-call shifts, physician office work, length of practice and specialisation.

Rangelia vitalii is a piroplasmid that causes canine rangeliosis, a severe hemorrhagic disease of domestic dogs in South America. We report about R. vitalii infecting a pampas fox (Lycalopex gymnocercus). The fox, which developed a fatal illness, was also infected by Hepatozoon canis and Capillaria hepatica.

Leptospirosis is a zoonotic disease of global importance caused by pathogenic Leptospira species. Dogs are reservoir hosts for pathogenic Leptospira and can act as potential transmission sources of the disease. Identification of such individuals and characterization of leptospires involved in chronic infections may promote a better understanding of the role of dogs in the epidemiology of particular leptospiral strains and the overall contribution of dogs to environmental contamination in urban and rural scenarios. The present work describes the identification of dogs presenting asymptomatic urinary shedding of different pathogenic Leptospira species among stray and sheltered dog populations, as well as the characterization of leptospiral strains isolated from chronic carriers. Blood and urine samples were taken from three different populations: (I) 92 dogs kept in a public shelter at the University of São Paulo campus; (II) seven stray dogs living inside the University of São Paulo campus; and (III) 24 dogs kept in a public shelter from the city of Mogi das Cruzes. Dogs identified as urinary shedders by PCR-based DNA detection were prospectively evaluated in order to confirm persistent renal carriage of the pathogen and to recover viable leptospires for proper characterization. Leptospiruric dogs were identified in all populations studied. Quantitative PCR targeting the lipL32 gene and the 16S rRNA detected urinary shedding in 10 dogs (10,87%) from population I: two of these dogs were recently admitted at the facility and one dog was adopted immediately after presenting large quantities of leptospires in urine. Prospective evaluation of nine leptospiruric dogs enabled the identification of two chronic carriers, allowing the recovery of leptospires from both dogs. The strains were further characterized by MLST analysis and serogrouping, thus confirming infection caused by L. interrogans serogroup Canicola and L. santarosai serogroup Sejroe. Two leptospiruric dogs (28,5%) were detected in population II by 16S and secY PCR amplification; one dog presented persistent urinary shedding of L. interrogans, but no isolates could be recovered. The other leptospiruric dog presented asymptomatic infection caused by L. santarosai and could not be reevaluated. Only one dog from population III (4,1%) presented leptospiruria detected by PCR; the dog could not be reevaluated, however sequence analysis revealed infection caused by L. santarosai. The results indicate the first report of L. santarosai infection in dogs. Asymptomatic infection caused by this leptospiral species was observed in all populations studied, thus indicating a possible role of dogs in the chain of transmission of this particular pathogen. The results also suggest a possible genetic distinction between lineages of Brazilian L. santarosai maintained by dogs and other animal hosts. Isolation and persistent chronic carriage of L. santarosai found shows that dogs can persistently harbor leptospires other than L. interrogans. This study also points out that dogs can be inadvertently admitted and adopted in dog shelters, potentially increasing the risks of occupational and zoonotic transmission by bringing infected animals closer to shelter workers, adopters and their households. A leptospirose é uma doença zoonótica de importância global causada por espécies patogênicas do gênero Leptospira. Cães são hospedeiros de manutenção de leptospiras patogênicas e podem atuar como potenciais fontes de infecção da doença. A identificação de tais indivíduos e a caracterização de leptospiras envolvidas na infecção crônica podem ajudar a compreender o papel dos cães na epidemiologia da doença tanto em ambientes rurais quanto urbanos. O presente trabalho descreve a identificação de cães errantes e mantidos em abrigos coletivos com eliminação assintomática de leptospiras patogênicas, além de descrever também a caracterização das diferentes estirpes obtidas de cães cronicamente infectados. Amostras de sangue e urina foram coletadas de 3 populações distintas: (I) 92 cães mantidos em um abrigo coletivo localizado dentro da Universidade de São Paulo; (II) sete cães errantes capturados dentro do campus da Universidade de São Paulo; e (III) 24 cães mantidos em um abrigo coletivo localizado na cidade de Mogi das Cruzes. Cães identificados como leptospirúricos por técnicas moleculares (PCR) foram prospectivamente avaliados para confirmar a persistência da eliminação bacteriana e para obter isolamento da cepa infectante e sua subsequente caracterização. A amplificação de fragmentos dos genes 16S rRNA e lipL32 permitiu a identificação de 10 cães (10,87%) leptospirúricos na população I. Dois dos 10 cães haviam sido recentemente admitidos no local, e outro cão foi adotado logo após apresentar grandes quantidades de leptospiras na urina. A avaliação prospectiva de nove animais leptospirúricos permitiu a caracterização da infecção crônica e assintomática em dois cães, o que possibilitou o isolamento de leptospiras de ambos os animais. As cepas foram tipificadas pelas técnicas de MLST e sorogrupagem, caracterizando duas cepas distintas, sendo elas L. interrogans sorogrupo Canicola e L. santarosai sorogrupo Sejroe. Dois cães leptospirúricos (28,5%) foram identificados na população II pela amplificação por PCR dos genes 16S rRNA e secY; um deles apresentou eliminação persistente de L. interrogans, no entanto não foi possível o isolamento do patógeno. O outro cão leptospirúrico não pôde ser reavaliado, entretanto a análise filogenética permitiu identificar infecção causada por L. santarosai. Apenas um cão da população III (4,1%) apresentou eliminação de leptospiras na urina, que foi confirmada pela amplificação de fragmento dos genes 16S rRNA e secY; o cão não pôde ser reavaliado, no entanto a análise filogenética dos fragmentos amplificados confirmou infecção causada por L. santarosai. Os resultados indicam o primeiro registro de infecção causada por L. santarosai em cães. A ocorrência da infecção assintomática causada por essa espécie nas três populações avaliadas indica um possível papel dos cães na cadeia de transmissão desse patógeno em centros urbanos, além de demonstrar que cães podem se tornar portadores de diferentes espécies de leptospiras. Os resultados sugerem uma possível distinção genotípica de cepas de L. santarosai mantidas por cães quando comparadas com estirpes desta espécie isoladas de outros hospedeiros. O presente estudo também foi capaz de demonstrar que cães leptospirúricos podem ser inadvertidamente admitidos ou adotados em abrigos coletivos, aumentando potencialmente os riscos de transmissão ocupacional e zoonótica da doença.

Leptospirosis is a zoonotic disease of global importance caused by pathogenic Leptospira species. Dogs can become asymptomatically infected, acting like reservoir hosts for pathogenic Leptospira, notably Leptospira interrogans serovar Canicola. Identification of such individuals and characterization of leptospires involved in chronic infections may unravel the role of dogs in the epidemiology of particular leptospiral strains. The aim of the present work was to describe the first Leptospira santarosai strain isolated from a dog. The dog was kept in a public shelter in Sao Paulo city, Brazil, and presented asymptomatic urinary shedding detected by PCR. Prospective evaluation was performed to fully characterize its chronic carrier state. The dog did not present anti-Leptospira titles or clinical/laboratorial abnormalities during the evaluations; nevertheless long-term urinary shedding was confirmed by PCR and leptospires were recovered from two occasions. The isolated strain was molecularly characterized by partial 16S rRNA and secY gene sequencing and MLST analysis. Serogroup identification was performed using polyclonal antibodies. The strain was identified as Leptospira santarosai, serogroup Sejroe. This is the first evidence in the literature of the isolation of L. santarosai in dogs. Our findings show that dogs can persistently harbor leptospires other than L. interrogans.

Quantity and variety of environmental antigens, age, diet, vaccine protocols, exercising practice and mucosal cytokine microenvironment are factors that influence serum immunoglobulin (Ig) levels. IgA, IgG, IgG(T) and IgM were quantified in 60 horses, which were classified into two groups, ‘intensive’ or ‘relaxed’, according to sanitary standards of the facilities and physical exercise to which animals were subjected to. The ‘intensive’ group presented lower means for all isotypes, but only IgA presented a significant (P < 0.0064) difference when compared to the ‘relaxed’ group. This suggests that mucosal immunity found in the ’intensive’ group is lower when compared to the ‘relaxed’ group. Our data suggest that athlete horses may be less poised to mount an effective mucosal immunity response to environmental challenges and should not be considered by the same perspectives as a free-ranging horse.