2. Universidad Cardenal Herrera-CEU

Background The Ibizan Hound is a canine breed native to the Mediterranean region, where leishmaniasis is an endemic zoonosis. Several studies indicate a low prevalence of this disease in Ibizan Hound dogs, whereas other canine breeds present a high prevalence. However, the underlying molecular mechanisms still remain unknown. The aim of this work is to analyse the relationship between serum levels of cytokines and the genomic profiles in two canine breeds, Ibizan Hound (resistant canine breed model) and Boxer (susceptible canine breed model). Methods In this study, we analyse the haplotypes of genes encoding cytokines related to immune response of Leishmania infantum infection in twenty-four Boxers and twenty-eight Ibizan Hounds apparently healthy using CanineHD DNA Analysis BeadChip including 165,480 mapped positions. The haplo.glm extension of haplo.score was used to perform a General Linear Model (GLM) regression to estimate the magnitude of individual haplotype effects within each cytokine. Results Mean levels of interferon gamma (IFN-γ), interleukin 2 (IL-2) and IL-18 in Boxer dogs were 0.19 ± 0.05 ng/ml, 46.70 ± 4.54 ng/ml, and 36.37 ± 30.59 pg/ml, whereas Ibizan Hound dogs present 0.49 ± 0.05 ng/ml, 64.55 ± 4.54 ng/ ml, and 492.10 ± 31.18 pg/ml, respectively. The GLM regression shows fifteen haplotypes with statistically significant effect on the cytokine serum levels (P < 0.05). The more relevant are IL6-CGAAG and IFNG-GCA haplotypes, which increase and decrease the IL-2, IL-8 and IFN-γ serum levels, respectively. Conclusions Haplotypes in the IFNG and IL6 genes have been correlated to serum levels of IFN-γ, IL-2 and IL-18, and a moderate effect has been found on IL8 haplotype correlated to IL-8 and IL-18 serum levels. The results indicate that the resistance to L. infantum infection could be a consequence of certain haplotypes with a high frequency in the Ibizan Hound dog breed, while susceptibility to the disease would be related to other specific haplotypes, with high frequency in Boxer. Future studies are needed to elucidate whether these differences and haplotypes are related to different phenotypes in immune response and expression gene regulation to L. infantum infections in dogs and their possible application in new treatments and vaccines.

Leishmaniosis is a zoonosis caused by Leishmania spp., an intracellular protozoan parasite. This parasite is transmitted by sandflies, and the disease is endemic in the Mediterranean basin. In recent years, the number of species which could be a reservoir of the parasite is increased. One of the most relevant species is the horse, due to their contact with humans and ability to control the disease, thus being a possible silent reservoir. In this study, we have analyzed the prevalence and factors related to L. infantum infection in healthy horses in the Mediterranean region. Epidemiological data and serum samples were obtained from 167 apparently healthy horses, and the presence of L. infantum was evaluated via the ELISA method and real-time PCR. The results show 27.5% of prevalence and that the main factors related to infection are equine breed, morphotype, outdoor living, use, and season. In conclusion, the prevalence of L. infantum infection in apparently healthy horses from eastern Spain (Mediterranean basin) is elevated. To control this zoonosis, it would be advisable to carry out more studies on this and other species that could be silent reservoirs of the parasite, as well as carry out measures such as the use of repellents on a regular basis.

Dogs are considered the main reservoir of several zoonoses endemic to the Mediterranean Basin. In this study, a prevalence of infections and coinfections of canine vector-borne diseases was analyzed in apparently healthy dogs of different canine pure breeds in Sicily (Italy), where these diseases are endemic. The seroprevalence of Leishmania infantum, Ricketsia ricketsii, Anaplasma phagocytophilum, and Erlichia canis was assessed, as single and coinfections. Biochemical and hematological parameters were evaluated, and epidemiological factors, including sex, age, and canine breed, were recovered. The most frequent infection was L. infantum (45.61%), following R. ricketsii (36.84%), both as single, double, or triple coinfections. Coinfections change the biochemical and hematological parameters of the host, and canine breeds are related to the infection frequency and the parameters observed during infections. Changes in the complete blood count (CBC) and biochemical values also differ between canine breeds, with the Cirneco dell’Etna dogs infected with L. infantum being the animals presenting the most interesting results in our study. High values of RBC, hemoglobin, hematocrit, mean corpuscular hemoglobin (MCH), the albumin/globulin (A/G) ratio, and albumin and low levels of β-2 globulin and γ-globulin were found only in this canine breed, suggesting some resistance to infection in these dogs. Future studies about the immune response of this canine breed could be interesting to determine their possible resistance to zoonotic pathogens, such as L. infantum.

Leishmaniasis and toxoplasmosis are two of the most common parasitic zoonoses. Leishmaniasis is endemic to 98 countries around the world, whereas toxoplasmosis is widely distributed throughout the world, causing significant health expenditure. Horses can play a relevant role in the transmission of the disease, being a silent reservoir, as clinical signs are not common. Serum samples from 166 horses living in eastern Spain (Mediterranean basin) were analysed to determine the presence of antibodies against Leishmania spp. and T. gondii by ELISA (Enzyme-linked Immunosorbent Assay.) The risk factors evaluated were the geographical area and the relative humidity and average temperature, and epidemiological factors such as sex, reproductive status, age, breed, morphotype, living with other domestic animals, use and access to the outdoors. Seroprevalence of Leishmania spp. and T. gondii infection was found 28.92%, and 16.27% respectively, whereas co-infection of the two parasites was found only in two males. Leishmania seroprevalence was high in castrated males and several mesodolichomorphic equine breeds used for teaching, as well as in outdoor animals. The most elevated seroprevalence was found in winter with higher levels of rainfall, whereas high seroprevalence of T. gondii was found in crossbreeding animals and those used for breeding. High seroprevalence of Leishmania spp. and T. gondii was found in horses of the Mediterranean basin. These data suggest that horses can act as a silent reservoir and that this species has high potential for transmission to humans, outdoor animals and in geographical areas with high average rainfall.

In Guatemala, three million people are at risk of contracting cutaneous leishmaniosis, primarily in the northern regions. Despite this alarming epidemiological situation, few faunistic studies of phlebotomine sand flies have been conducted in this country, which is the most populous in Central America. An entomological survey of phlebotomine sand flies was carried out from March to September, 2018 in rural, mountainous, and forested areas of six northern Guatemalan departments with active transmission of human leishmaniosis: Petén, Huehuetenango, Quiché, Alta Verapaz, Izabal, and El Progreso. CDC miniature light traps were deployed in and around homes with recent cases of leishmaniosis in children under 10 years of age. A total of 2,605 specimens of sand flies were captured and identified, belonging to three subtribes, nine genera, and 14 species (13 of which were able to be determined), with a balanced sex ratio of 0.95 males per each female. Lutzomyia longipalpis was the most abundant species in the survey, accounting for 62.61% of the total catches; however, this species was restricted to El Progreso and Huehuetenango, with Huehuetenango having the highest capture percentage (55.54%). This vector was predominantly found outdoors, mostly in extra-domicile areas (62.29%). The male/female ratio for this species was 1.94. This study, and the entomological data we present, can aid in enhancing vector control interventions in these northern departments, thereby decreasing the incidence of leishmaniosis in humans.

Leishmaniosis is considered the most important neglected tropical disease caused by protozoan parasites in Southern European countries such as Spain. Its main etiological agent is Leishmania infantum while Phlebotomus perniciosus and Phlebotomus ariasi are the main vectors in the country. During the first half of July 2021, an entomological survey was conducted in a dog shelter and its surroundings in the municipality of Toledo (Castilla-La Mancha). Sand fly sticky traps, made of A5-size white paper coated with castor oil, were placed in six different environments inside a 200 m (the mean flight distance of Phlebotomus sp.) radius from the animal shelter. Sticky traps were set for eleven consecutive trapping nights in each site. A total of 356 phlebotomine sand flies belonging to four species in two genera were identified. These species and their abundance in the traps were: Sergentomyia minuta (70.2%), Phlebotomus perniciosus (25.9%), Phlebotomus sergenti (2.8%), and Phlebotomus papatasi (1.1%). The following list gives a breakdown of the abundance of phlebotomine sand flies found in various locations: a burrow (45.1%), a maintenance warehouse (21.3%), a holm oak´s tree hole (15.6%), an abandoned cattle barnyard (10.3%), a dog kennels area (4.3%), and surroundings of a feral feline colony (3.3%). Phlebotomus papatasi, an anthropophagic species, was only found in crevices of the maintenance warehouse. Although dogs are considered the main Leishmania reservoir, this preliminary research shows the effect of different micro-environments in the surroundings of animal shelters on sand fly abundance and diversity, and the importance that other reservoirs could play as most documented captures were associated with glires (orders Rodentia and Lagomorpha) rather than dogs and cats.