Servo-idemiology of leptospirosis in dogs on the island of Barbados (2023)

Dogs are thought to be highly exposed to the environmental pathogen leptospira, which can act as potential sources of infection for zoonotic transmission. Vaccination is the cornerstone strategy for preventing disease and urinary leakage in dogs, but the success of vaccination depends largely on the similarity of locally circulating leptospira to those used in vaccine formulations. To provide evidence of vaccine compatibility and to assess whether there are regional differences in serogroup distribution, we performed a systematic review including meta-analysis of serological data, characterization of leptospiral isolates and risk factors for seropositivity in dogs from Brazil. Studies reporting canine leptospirosis in the Brazilian territory were eligible for inclusion and the method was validated by PROSPERO under registration CRD42020204187. Six electronic databases were searched and data on population, methods and results were extracted. 61 studies were included to access serogroup distribution and risk factors with an overall positivity rate of 19.7% in the dog population. Serological evidence indicates that Canicola, Icterohaemorrhagiae and Autumnalis are the most common serogroups. Twenty-eight records were included to access leptospiral strains isolated in Brazil, with n=56 strains characterized as serogroups Canicola, n=37 as Icterohaemorrhagiae, n=2 as Pomona and n=1 strain as Australis and Sejroe each. Risk factor analysis showed that stray dogs, puppies or older dogs, male dogs and dogs kept by educators with poor social and economic conditions have a high risk of infection. The current study revealed generally good compatibility of leptospiral strains circulating locally with those used in canine leptospirosis vaccines in Brazil. The circulation of serovars Pomona and Grippotyphosa has not been consistently demonstrated, and the inclusion of these serovars in topical vaccines cannot be supported by our results. The results also provided serological evidence for the circulation of Serogroup Autumnalis among the studied populations.

This systematic review summarizes the data published onLeptospiraseroprevalence, serovar diversity and distribution among animal species in the Caribbean. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and checklist, relevant articles were identified and data were extracted and recorded. The review deliveredLeptospiraseroprevalence data from 16 Caribbean islands (Barbados, Trinidad, Grenada, Puerto Rico, Saint Croix, St. Kitts and Nevis, Jamaica, Antigua, Carriacou, Dominica, Guadalupe, Martinique, Monserrat, St. Lucia, St. Maarten and St. Vincent ) in different animal species. A review of the literature revealed the limited amount of data available from a limited number of islands. Many of the studies conducted have recorded seroprevalences based on variable and small sample sizes. In addition, the serovar panels used for MAT were not consistent between studies. The review shows thatLeptospiraexposure in a given geographic location may change with time and with climatic and environmental conditions, emphasizing the need for ongoing monitoring in tropical countries where the climate supports sustainedLeptospirain the residential environment. Particular attention should be paid to standardizing MAT panels and protocols and providing training to all laboratories involved in testing. Additional animal and environmental experiments to isolate and identify circulationLeptospiraspp. in a geographical region should be actively pursued. This knowledge is important for implementing geographically specific control programs, as risk factors forLeptospiraTransfer is favored by several factors such as changes in climatic conditions, urbanization, degradation of wildlife habitats, import/export of animals, increase in adventure travel and water-related recreational activities.

The diagnostic tool for the standard diagnosisLeptospiraIgM ELISA for detection of acute leptospirosis was evaluated in febrile adults hospitalized in Vientiane, Laos. Using the cut-off [optical density (OD) ≥0.75] suggested by the manufacturer, the assay showed limited diagnostic power with a sensitivity of 95% and a specificity of 41% compared toLeptospiramicroscopic agglutination test, the serological gold standard. However, reevaluation of the diagnostic cut-off to an OD of 1.7 showed improved diagnostic accuracy overall (sensitivity 70%; specificity 78%).

Leptospirosis is a zoonotic disease that is underreported in many countries, including Trinidad and Tobago, due to a low level of awareness of the disease. A Leptospirosis Knowledge, Attitudes and Practices (KAP) survey was conducted among 800 households across Trinidad to determine the level of awareness of the disease in the country. Of the participants, 52.4% had heard of leptospirosis, but about half of these had no signs or symptoms of the disease. Knowledge of leptospirosis was not related to people's level of education, but to geographic location. About 82% of participants engaged in at least one high-risk activity, the most common of which was walking outdoors barefoot. The animal most of the participants interacted with was the dog. Of the 53% of participants who had seen a mouse or rat in their home, 5% used the regional company's free monitoring services. About 66% of the participants were not satisfied with the services provided by the regional company. There was a positive attitude towards general health and good sanitation practices among the population of Trinidad, but there was also a lack of knowledge about leptospirosis. The low level of awareness of leptospirosis in Trinidad makes it a public health problem, as it is often confused with dengue, which is better known in the country.

Journal of Infection, Volume 68, Issue 2, 2014, p. 141-148

One Health, bind 12, 2021, artikel 100232

Journal of Infection, bind 67, hæfte 6, 2013, s. 565-573

Journal of Solid State Chemistry, bind 212, 2014, s. 205-212

Large single crystals of orthorhombic${[{({\mathrm{CH}}_3)}_3{\mathrm{NCH}}_2\mathrm{COO}]}_2{({\mathrm{CuCl}}_2)}_3·2{\mathrm{H}}_2\mathrm{O}$with dimensions up to 40×40×30mm³were grown from aqueous solutions. The elastic and piezoelastic coefficients were derived from ultrasonic resonance frequencies and their displacements with variation of pressure, respectively, using the plate resonance technique. Additionally, the thermal expansion coefficients were determined between 95K and 305K by dilatometry. The elastic behavior at ambient conditions is dominated by the two-dimensional network of strong hydrogen bonds in the (001) plane, leading to a corresponding pseudo-tetragonal anisotropy of the longitudinal elastic stiffness. However, the variation of elastic properties with pressure, as well as the thermal expansion, show strong deviations from the pseudo-tetragonal symmetry. These deviations are probably correlated with slopes of the elongated tri-nuclear betaine-CuCl₂– aquatic complexes. Neither the thermal expansion nor the specific heat capacity gives any indication of a phase transition in the investigated temperature range.

Clinical Veterinary Review, bind 49, udgave 3, 2014, s. 115-122

Preventive veterinary medicine, volume 135, 2016, pp. 59-66

Management strategies for dog populations and their diseases include reproductive control, culling, and vaccination. However, the effectiveness of these strategies can be severely compromised by human-mediated dog movements. If immigration is important, then the place of origin of human-imported dogs will be fundamental in defining the spatial scales at which population management and research must be applied. In this context, the main objective of our study was to determine the spatial extent of the demographic processes of dogs in rural areas and the proportion of dogs that could be designated as immigrants at several spatial scales. To achieve our goal, we surveyed households in a landscape in southern Chile. Through interviews, we were able to obtain information about the demographics of dogs in this rural environment, the human impact on dog deaths and births, the areas of origin of dogs living in rural areas, and the spatial extent of human-mediated dog movements. We found that most rural dogs (64.1%) were urban dogs brought to the countryside (40.0%) or adopted dogs previously abandoned on the country roads (24.1%). Some dogs were brought from areas as far as 700 km from the study area. Human-mediated movements of dogs, particularly from urban areas, appear to play a fundamental role in rural dog population dynamics. As a result, local efforts to control dog populations or their diseases are unlikely to succeed if conducted in isolation simply because dogs may be brought in from surrounding urban areas or even distant locations. We suggest that efforts to manage or study dog ​​populations and associated diseases should be conducted using a multi-scale approach.