ABSTRACT
Leptospirosis is a zoonotic disease with significant global impact and a challenging diagnosis. The utilization of adequately validated rapid tests is relevant for the opportune identification of the disease and for reduction in fatality rates. The present study analyzes the accuracy and reliability of the Dual Path Platform (DPP) assay -produced in Brazil by the Oswaldo Cruz Foundation (Fiocruz)- for diagnosing leptospirosis. Firstly, a serological panel was constructed in the Brazilian Reference Laboratory for Leptospirosis using samples routinely handled by reference laboratories of six Brazilian states. It consisted of 150 positive (according to MAT and IgM-ELISA) and 250 negative samples for leptospirosis. Subsequently, the panel samples were distributed to the reference laboratories for the performance of DPP assays in triplicate. Different measures were used in the assessment of diagnostic quality. Predictive values were estimated for different pre-test probability settings. Sensitivities varied between 67.33 % and 74.00 % and specificities between 93.20 % and 98.40 % in the states, and there were adequate agreements between them. Accuracies were lower for the samples of patients with less than 7 days of symptoms. In contexts of prevalence values up to around 25 %, positive and negative predictive values were around 90 %. However, in situations of high pre-test probabilities, NPVs were low. This study improves understanding of the use of DPP in diagnosing leptospirosis, particularly its application in healthcare settings. As long as the time of symptoms onset and clinical and epidemiological contexts are adequately considered for the interpretation of results, DPP is a valid option to be used in the leptospirosis diagnostic routine.
Subject(s)
Antibodies, Bacterial , Leptospirosis , Sensitivity and Specificity , Leptospirosis/diagnosis , Humans , Brazil/epidemiology , Antibodies, Bacterial/blood , Reproducibility of Results , Leptospira/isolation & purification , Leptospira/immunology , Enzyme-Linked Immunosorbent Assay/methods , Adult , Male , Female , Immunoglobulin M/blood , Predictive Value of Tests , Middle Aged , Adolescent , Serologic Tests/methodsABSTRACT
Responsible companion animal guardianship (RCAG) covers aspects that are relevant to both animal and human health. Understanding the factors associated with adherence to RCAG principles can guide accountability, animal welfare and disease control. The present observational study describes the level of adherence to RCAG by guardians living in a medium-sized Brazilian municipality and identifies the factors associated with inadequate guardianship. Questionnaires were administered to randomly selected guardians of 704 dogs. The binary outcome of the study, namely more and less adequate compliers to RCAG principles, was analyzed using a score list comprising eight variables relating to the care provided to the dogs, namely provision of veterinary services, vaccination against rabies, deworming, no access to the streets without supervision, walking with guardian, dog freedom at home, registration (microchipping) and satisfactory food supply. Factors possibly associated with less adequate adherence to RCAG by the guardian, such as socioeconomic and cultural features of the guardians, characteristics of the dogs and attributes of the guardian-animal interactions, were analyzed using multiple logistic regression models. The RCAG actions least adopted by guardians were animal registration, provision of veterinary care, walking with the dog and preventing access of the dogs to the streets without supervision. Individuals who cared for a single dog, a mixed breed dog or had previously lost a dog were less likely to show adequate adherence to RCAG. Conversely, guardians who owned cars, acquired dogs as puppies, lived in households with a maximum of four residents, cared for a sterilized dog or thought that caring for a dog was easier than (or as) expected, had a higher chance of showing adequate adherence to RCAG. The results verify that the socioeconomic and behavioral characteristic of guardians must be taken into consideration for understanding the adherence to RCAG. In addition, it is important to facilitate access to veterinary services and to raise awareness about the significance of a safe and healthy environment for companion animals.
Subject(s)
Animal Welfare , Animals , Brazil , Dogs , Male , Humans , Female , Pets , Ownership/statistics & numerical data , Surveys and Questionnaires , AdultABSTRACT
Understanding the distribution of dogs in the environment is relevant for establishing human and animal health actions. In the present study, we analyzed the influence of community feeders and commercial food outlets on the spatial distribution of free-roaming dogs in an urban area of a municipality in Southeast Brazil. The dogs were identified via photographic capture and recapture performed over five sampling efforts. The spatial densities of dogs were determined using the Kernel method. Spatial correlations between the distribution of free-roaming dogs and the locations of community feeders and commercial food outlets were analyzed using the K function. During the study, 1207 captures/recaptures were performed encompassing 554 dogs, the majority (62.6%) of which were males. Agglomerations of male and female dogs were observed in the areas where food was present. Positive spatial autocorrelations were detected between the distribution of dogs and food sources. The median distances between dogs and community feeders or commercial food outlets were 1.2 and 1.4 km, respectively, and the difference between these two was statistically significant. The presence of community feeders and food outlets demonstrates the influence of human activity, on the spatial distribution of free-roaming dogs. These results will be useful for developing strategies aimed at the improvement of animal welfare and the prevention of zoonoses.
ABSTRACT
The permanence of a dog in a household is relevant in terms of public health and animal welfare because it implies that the animal is receiving better care and is unlikely to be abandoned. We have performed a survey in a medium-sized city in southeastern Brazil in order to identify predictors associated with the non-permanence of dogs in households as determined one year after the first visit. During the first of two visits to randomly selected domiciles, guardians were asked to complete a structured questionnaire regarding the traits and history of each dog in the household, features of the domicile, characteristics of the guardian and adherence to the principles of responsible companion animal guardianship (RCAG). A second visit to each domicile was performed one year later in order to establish in loco whether the dog still resided in the domicile and, where appropriate, to apply a further questionnaire concerning the fate of the missing animal. The total sample population comprised 513 dogs, of which 98 (19.1%) were verified as no longer resident in the domicile on the occasion of the second visit. Of the absent dogs, 59 had died as a result of fights with stray animals, traffic accidents, diseases or old age, 13 had been sent to alternative addresses, 8 had been donated to third parties and 7 had escaped from the domicile. The fates of the remaining 11 animals were not divulged by the guardians. Multiple regression analysis revealed that the risk of non-permanence was significantly higher (p < 0.05) among male dogs, those that were infested with ticks, had free access to the streets or resided in domiciles near a wooded area, but was significantly lower among wormed and neutered dogs. The adoption of RCAG principles is associated with the permanence of dogs in households and, consequently, in reduction of the stray population, animal well-being and prevention of zoonoses. On this basis, it is important to raise awareness about the concepts of RCAG and to strengthen accountability of guardians that do not take proper care of their animals.
Subject(s)
Animal Welfare , Dog Diseases , Animals , Brazil/epidemiology , Dog Diseases/epidemiology , Dogs , Family Characteristics , Male , Surveys and Questionnaires , ZoonosesABSTRACT
BACKGROUND: Responsible companion animal guardianship (RCAG) comprises a set of concepts involving activities, behavior and care that guardians must provide to ensure the welfare of their animals. When such principles are disregarded, the risk of animals developing zoonotic diseases, such as canine visceral leishmaniasis (CVL), increases. This disease is a public health problem in many urban settings in Brazil because dogs are the main reservoirs of Leishmania and are involved in the transmission of the parasites to humans. Our analytical cross-sectional epidemiological survey aimed to investigate the prevalence of CVL in a city in southeastern Brazil and to establish the association between the disease and a number of predictor variables including dog traits, socioeconomic status of guardians, ecological features of the domicile and RCAG. RESULTS: Our study showed that the global prevalence of CVL in the sample canine population was 6.7% (47/704). All variables related to better dog care were associated with lower chances of infection. Multiple regression analysis revealed that the chances of animals being seropositive for CVL were significantly (p < 0.05) higher when guardians had no formal education or possessed a university degree (vs. those with complete primary or secondary schooling) and when dogs were sheltered outside the house and had free access to the streets. An additional novel finding was that dogs that were acquired as puppies presented half of the chance of developing the disease in comparison with those acquired at the adult stage. Geographically weighted logistic regression coefficients showed that the strengths of the predictor/CVL associations varied depending on the studied geographical space. Both models demonstrated that the associations were always in the same directions. CONCLUSIONS: Our findings indicate that regardless of age and mode of acquisition, adult dogs should be submitted to clinical evaluation and tests for CVL. RCAG can exert positive effects on the control of CVL.
Subject(s)
Dog Diseases , Leishmaniasis, Visceral , Animals , Brazil/epidemiology , Cross-Sectional Studies , Dog Diseases/epidemiology , Dog Diseases/parasitology , Dogs , Humans , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/veterinary , PetsABSTRACT
The existence of free-roaming dogs raises important issues in animal welfare and in public health. A proper understanding of these animals' ecology is useful as a necessary input to plan strategies to control these populations. The present study addresses the population dynamics and the effectiveness of the sterilization of unrestricted dogs using capture and recapture procedures suitable for open animal populations. Every two months, over a period of 14 months, we captured, tagged, released and recaptured dogs in two regions in a city in the southeast region of Brazil. In one of these regions the animals were also sterilized. Both regions had similar social, environmental and demographic features. We estimated the presence of 148 females and 227 males during the period of study. The average dog:man ratio was 1 dog for each 42 and 51 human beings, in the areas without and with sterilization, respectively. The animal population size increased in both regions, due mainly to the abandonment of domestic dogs. Mortality rate decreased throughout the study period. Survival probabilities did not differ between genders, but males entered the population in higher numbers. There were no differences in abundance, survival and recruitment between the regions, indicating that sterilization did not affect the population dynamics. Our findings indicate that the observed animal dynamics were influenced by density-independent factors, and that sterilization might not be a viable and effective strategy in regions where availability of resources is low and animal abandonment rates are high. Furthermore, the high demographic turnover rates observed render the canine free-roaming population younger, thus more susceptible to diseases, especially to rabies and leishmaniasis. We conclude by stressing the importance of implementing educational programs to promote responsible animal ownership and effective strategies against abandonment practices.
Subject(s)
Sterilization, Reproductive/veterinary , Animals , Brazil , Dogs , Female , Humans , Male , Population Density , Survival RateABSTRACT
Identification of factors associated with Leishmania infection in dogs is essential for targeting visceral leishmaniasis control actions. Thus, the present study analyzed some of these factors in a population of dogs in a Brazilian municipality, along with the limitations of control strategies implemented there. The association between the exposure variables and occurrences of infection was analyzed through logistic regression models. The disease control interventions were treated qualitatively. Out of the 755 animals examined, 13.6% (103/755) were seropositive. Of these, 23.3% (24/103) were asymptomatic and 76.7% (79/103) presented at least one clinical sign possibly associated with visceral leishmaniasis. With weak associations, purebred, shorthaired, over 5 years of age, male and large dogs were more prone to infection. The latter two variables formed the final regression model and the association with dog size was statistically significant. The control strategies developed presented limitations and a great number of seronegative dogs was culled. The data presented contribute towards better understanding of the dynamics of infection in canine visceral leishmaniasis and indicate that actions aimed towards adequate implementation of Visceral Leishmaniasis control program in Brazilian endemic areas should be prioritized.
A identificação dos fatores associados à infecção por Leishmania em cães é essencial para o direcionamento das ações de controle da leishmaniose visceral. Desta forma, o presente estudo analisa alguns destes fatores em uma população de cães, bem como as limitações das estratégias de controle executadas em um município brasileiro. Por meio de modelos de regressão logística, analisou-se a associação entre as variáveis de exposição e a ocorrência de infecção. As ações de controle da doença foram analisadas qualitativamente. Dos 755 animais avaliados por meio de sorologia, 13,6% (103/755) foram soro-reagentes. Destes, 23,3% (24/103) eram assintomáticos e 76,7% (79/103) apresentaram pelo menos um sinal clínico possivelmente associado com a leishmaniose visceral. Com associações fracas, cães de raça pura, de pelo curto, com mais de cinco anos, machos e de grande porte foram mais propensos à infecção. As duas últimas variáveis compuseram o modelo final de regressão, sendo significativa a associação com o tamanho do cão. As estratégias de controle desenvolvidas apresentaram limitações e um número elevado de cães sorologicamente negativos foi submetido a eutanásia. Os dados apresentados contribuem para um melhor entendimento da dinâmica da infecção na leishmaniose visceral canina e indicam que ações visando a adequada execução do programa de controle da doença em áreas endêmicas brasileiras devem ser priorizadas.
Subject(s)
Animals , Dogs , Female , Male , Dog Diseases/epidemiology , Dog Diseases/parasitology , Leishmaniasis, Visceral/veterinary , Brazil , Dog Diseases/diagnosis , Dog Diseases/prevention & control , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/prevention & controlABSTRACT
Identification of factors associated with Leishmania infection in dogs is essential for targeting visceral leishmaniasis control actions. Thus, the present study analyzed some of these factors in a population of dogs in a Brazilian municipality, along with the limitations of control strategies implemented there. The association between the exposure variables and occurrences of infection was analyzed through logistic regression models. The disease control interventions were treated qualitatively. Out of the 755 animals examined, 13.6% (103/755) were seropositive. Of these, 23.3% (24/103) were asymptomatic and 76.7% (79/103) presented at least one clinical sign possibly associated with visceral leishmaniasis. With weak associations, purebred, shorthaired, over 5 years of age, male and large dogs were more prone to infection. The latter two variables formed the final regression model and the association with dog size was statistically significant. The control strategies developed presented limitations and a great number of seronegative dogs was culled. The data presented contribute towards better understanding of the dynamics of infection in canine visceral leishmaniasis and indicate that actions aimed towards adequate implementation of Visceral Leishmaniasis control program in Brazilian endemic areas should be prioritized.