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Abstract Background Canine leishmaniosis (CanL), caused by Leishmania infantum, is an important vector-borne parasitic disease in dogs with implications for human health. Despite advancements, managing CanL remains challenging due to its complexity, especially in chronic, relapsing cases. Mathematical modeling has emerged as a powerful tool in various medical fields, but its application in understanding CanL relapses remains unexplored. Methods This retrospective study aimed to investigate risk factors associated with disease relapse in a cohort of dogs naturally infected with L. infantum. Data from 291 repeated measures of 54 dogs meeting the inclusion criteria were included. Two logistic mixed-effects models were created to identify clinicopathological variables associated with an increased risk of clinical relapses requiring a leishmanicidal treatment in CanL. A backward elimination approach was employed, starting with a full model comprising all potential predictors. Variables were iteratively eliminated on the basis of their impact on the model, considering both statistical significance and model complexity. All analyses were conducted using R software, primarily employing the lme4 package, and applying a significance level of 5% (P

Abstract Background Leishmaniosis caused by Leishmania infantum, L. major and L. tropica is endemic in Morocco. Growing evidence of both human and canine Leishmania infections in urban centres has been reported. Since many forms of the disease are zoonotic, veterinarians play an important role in leishmaniosis control by intervening at the parasite host level. This study aimed to bring together One Health principles to connect canine and feline leishmaniosis epidemiology within urban centres of Morocco (Rabat and Fez) and assess the level of awareness of Moroccan veterinarians about facing this threat. Methods A molecular survey was conducted for Leishmania DNA detection in canine (n = 155) and feline (n = 32) whole-blood samples. Three conventional polymerase chain reaction (PCR) protocols were implemented. The first PCR aimed at identifying infected animals by targeting Leishmania spp. kinetoplast minicircle DNA (kDNA). The second and third PCR targeted the Leishmania internal transcribed spacer region (ITS-1) and the Leishmania small subunit ribosomal RNA (SSUrRNA) gene, respectively, aiming at identification of the infecting species after Sanger sequencing-positive amplicons. Total immunoglobulin G (IgG) against Leishmania spp. was evaluated in 125 dogs by enzyme-linked immunosorbent assays (ELISA) using an in-house protocol, including three Leishmania-specific antigens (SPLA, rKDDR and LicTXNPx). Sera from 25 cats were screened for total IgG to Leishmania spp. by an indirect immunofluorescence antibody test (IFAT). An online questionnaire was presented to Moroccan veterinarians addressing their knowledge and practices towards animal leishmaniosis. Results Overall, 19.4% of the dogs tested positive for Leishmania kDNA and ITS-1 and sequencing revealed infection with L. infantum among PCR-positive dogs. These animals presented a wide range of ELISA seropositivity results (16.7%, 34.9% and 51.6%) according to the tested antigens (rKDDR, SPLA and LicTXNPx, respectively). Use of kDNA-PCR revealed 12.5% cats positive to Leishmania spp. otherwise found to be seronegative by IFAT. Conclusions A considerable prevalence of infection was identified in dogs from urban centres of Morocco. Additionally, this is the first report of feline infection with Leishmania spp. in this country and in urban settings. Moroccan veterinarians are aware that animal leishmaniosis is endemic in Morocco, representing a public health threat, and are knowledgeable about canine leishmaniosis diagnosis and treatment. Graphical Abstract

Abstract Background Dogs are considered the main domestic animals that may be a reservoir for Leishmania infantum, the agent of zoonotic visceral leishmaniasis (ZVL) in several countries of the world. The dog may host other Leishmania species, but its epidemiological role in the maintenance and spreading of these parasites is not completely elucidated. Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, affects thousands of people every year and is particularly diffused in many countries of North Africa and Middle East Asia. In ZCL endemic countries, few reports of L. major-positive dogs have been reported, probably because most human cases occur in poor rural areas where the social role of the dog and its medical management is not well considered. The aim of the present study is to better understand the possible involvement of domestic dogs in the epidemiology of ZCL. Methods Our research focused on a well-established endemic focus of ZCL, in the area of Echrarda, Kairouan Governorate, central Tunisia. A total of 51 dogs with no or mild clinical signs of vector borne diseases were selected in small villages where human cases of ZCL are yearly present. All dogs were sampled for the Leishmania spp. diagnosis, by using the following procedures: blood sample for serology and buffy coat quantitative polymerase chain reaction (qPCR), popliteal fine needle aspiration, and cutaneous biopsy punch for lymph node and skin qPCR. Results The results demonstrated a high percentage (21.6%) of dogs positive at least at one or more test; the most sensitive technique was the lymph node qPCR that detected 8/11 positive dogs. Nine, out of the eleven positive dogs, resulted as infected by Leishmania infantum; ITS1-PCR-sequencing allowed Leishmania major identification in the remaining two cases, both from the popliteal lymph node samples, which can suggest a possible visceral spread of a cutaneous Leishmania species in the dog. Interestingly, one of the two L. major-positive dogs was living in the same house where 6-year-old children showed cutaneous lesions referred to as ZCL. Conclusions To our knowledge, this is the first report of L. major-positive dogs in Tunisia, the epidemiological role of which remains under investigation. Graphical Abstract

Abstract Background In endemic areas, Leishmania infantum and feline immunodeficiency virus (FIV) co-infection occurs in cats, and may favour a progressive course of feline leishmaniosis. Abnormalities in serum protein fractions have been reported, but inflammation markers have scarcely been studied. Erythrocyte sediment rate (ESR) is a marker of inflammation that is poorly used in veterinary medicine, but it has been evaluated in EDTA blood using a recently introduced automatic device. We studied ESR and a pool of feline markers of inflammation (MoI) in cats L. infantum (Li +) and/or FIV antibody-positive (Li +FIV+/FIV+) with the aims (a) to evaluate ESR as MoI in cats with the infectious and clinical conditions considered and (b) to provide data about a pool of MoI never investigated in the feline infections studied and in other cat diseases before. Methods This prospective controlled study included 35 study group cats (Li +, n = 20; FIV +, n = 8; Li +FIV+, n = 7) and ten healthy antibody-negative control cats. Clinical findings at physical examination and selected clinical pathological abnormalities related to inflammation were statistically analysed in relation to the infectious status and ESR values. Results ESR values were higher in Li +, FIV+, and Li +FIV+ cats compared with control cats, and 40% of the study group cats had ESR values above the reference interval (RI). ESR positively correlated with some positive MoI and negatively with some negative MoI studied. Additionally, a higher prevalence of ESR values above the RI has been detected in cats with hypoalbuminemia or hypergammaglobulinemia and higher ESR values were measured in cats with serum protein electrophoresis (SPE) fraction abnormalities. Correlations were also found with erythrocytes, hemoglobin, hematocrit and some erythrocyte indices. FIV+ and Li +FIV+ cats had a higher prevalence of increased ESR values, and almost all had SPE abnormalities and more severe clinical presentations compared with Li + cats. Conclusions Abnormal levels of MoI were found in almost all parameters studied, particularly in FIV+ and Li +FIV+ cats. Also, ESR can be used as a marker of inflammation in cats with L. infantum and/or FIV infection. Graphical Abstract

Background: Leishmaniosis caused by Leishmania infantum, L. major and L. tropica is endemic in Morocco. Growing evidence of both human and canine Leishmania infections in urban centres has been reported. Since many forms of the disease are zoonotic, veterinarians play an important role in leishmaniosis control by intervening at the parasite host level. This study aimed to bring together One Health principles to connect canine and feline leishmaniosis epidemiology within urban centres of Morocco (Rabat and Fez) and assess the level of awareness of Moroccan veterinarians about facing this threat. Methods: A molecular survey was conducted for Leishmania DNA detection in canine (n = 155) and feline (n = 32) whole-blood samples. Three conventional polymerase chain reaction (PCR) protocols were implemented. The first PCR aimed at identifying infected animals by targeting Leishmania spp. kinetoplast minicircle DNA (kDNA). The second and third PCR targeted the Leishmania internal transcribed spacer region (ITS-1) and the Leishmania small subunit ribosomal RNA (SSUrRNA) gene, respectively, aiming at identification of the infecting species after Sanger sequencing-positive amplicons. Total immunoglobulin G (IgG) against Leishmania spp. was evaluated in 125 dogs by enzyme-linked immunosorbent assays (ELISA) using an in-house protocol, including three Leishmania-specific antigens (SPLA, rKDDR and LicTXNPx). Sera from 25 cats were screened for total IgG to Leishmania spp. by an indirect immunofluorescence antibody test (IFAT). An online questionnaire was presented to Moroccan veterinarians addressing their knowledge and practices towards animal leishmaniosis. Results: Overall, 19.4% of the dogs tested positive for Leishmania kDNA and ITS-1 and sequencing revealed infection with L. infantum among PCR-positive dogs. These animals presented a wide range of ELISA seropositivity results (16.7%, 34.9% and 51.6%) according to the tested antigens (rKDDR, SPLA and LicTXNPx, respectively). Use of kDNA-PCR revealed 12.5% cats positive to Leishmania spp. otherwise found to be seronegative by IFAT. Conclusions: A considerable prevalence of infection was identified in dogs from urban centres of Morocco. Additionally, this is the first report of feline infection with Leishmania spp. in this country and in urban settings. Moroccan veterinarians are aware that animal leishmaniosis is endemic in Morocco, representing a public health threat, and are knowledgeable about canine leishmaniosis diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Background: Dogs are considered the main domestic animals that may be a reservoir for Leishmania infantum, the agent of zoonotic visceral leishmaniasis (ZVL) in several countries of the world. The dog may host other Leishmania species, but its epidemiological role in the maintenance and spreading of these parasites is not completely elucidated. Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, affects thousands of people every year and is particularly diffused in many countries of North Africa and Middle East Asia. In ZCL endemic countries, few reports of L. major-positive dogs have been reported, probably because most human cases occur in poor rural areas where the social role of the dog and its medical management is not well considered. The aim of the present study is to better understand the possible involvement of domestic dogs in the epidemiology of ZCL. Methods: Our research focused on a well-established endemic focus of ZCL, in the area of Echrarda, Kairouan Governorate, central Tunisia. A total of 51 dogs with no or mild clinical signs of vector borne diseases were selected in small villages where human cases of ZCL are yearly present. All dogs were sampled for the Leishmania spp. diagnosis, by using the following procedures: blood sample for serology and buffy coat quantitative polymerase chain reaction (qPCR), popliteal fine needle aspiration, and cutaneous biopsy punch for lymph node and skin qPCR. Results: The results demonstrated a high percentage (21.6%) of dogs positive at least at one or more test; the most sensitive technique was the lymph node qPCR that detected 8/11 positive dogs. Nine, out of the eleven positive dogs, resulted as infected by Leishmania infantum; ITS1-PCR-sequencing allowed Leishmania major identification in the remaining two cases, both from the popliteal lymph node samples, which can suggest a possible visceral spread of a cutaneous Leishmania species in the dog. Interestingly, one of the two L. major-positive dogs was living in the same house where 6-year-old children showed cutaneous lesions referred to as ZCL. Conclusions: To our knowledge, this is the first report of L. major-positive dogs in Tunisia, the epidemiological role of which remains under investigation. [ABSTRACT FROM AUTHOR]

Background: In endemic areas, Leishmania infantum and feline immunodeficiency virus (FIV) co-infection occurs in cats, and may favour a progressive course of feline leishmaniosis. Abnormalities in serum protein fractions have been reported, but inflammation markers have scarcely been studied. Erythrocyte sediment rate (ESR) is a marker of inflammation that is poorly used in veterinary medicine, but it has been evaluated in EDTA blood using a recently introduced automatic device. We studied ESR and a pool of feline markers of inflammation (MoI) in cats L. infantum (Li+) and/or FIV antibody-positive (Li+FIV+/FIV+) with the aims (a) to evaluate ESR as MoI in cats with the infectious and clinical conditions considered and (b) to provide data about a pool of MoI never investigated in the feline infections studied and in other cat diseases before. Methods: This prospective controlled study included 35 study group cats (Li+, n = 20; FIV +, n = 8; Li+FIV+, n = 7) and ten healthy antibody-negative control cats. Clinical findings at physical examination and selected clinical pathological abnormalities related to inflammation were statistically analysed in relation to the infectious status and ESR values. Results: ESR values were higher in Li+, FIV+, and Li+FIV+ cats compared with control cats, and 40% of the study group cats had ESR values above the reference interval (RI). ESR positively correlated with some positive MoI and negatively with some negative MoI studied. Additionally, a higher prevalence of ESR values above the RI has been detected in cats with hypoalbuminemia or hypergammaglobulinemia and higher ESR values were measured in cats with serum protein electrophoresis (SPE) fraction abnormalities. Correlations were also found with erythrocytes, hemoglobin, hematocrit and some erythrocyte indices. FIV+ and Li+FIV+ cats had a higher prevalence of increased ESR values, and almost all had SPE abnormalities and more severe clinical presentations compared with Li+ cats. Conclusions: Abnormal levels of MoI were found in almost all parameters studied, particularly in FIV+ and Li+FIV+ cats. Also, ESR can be used as a marker of inflammation in cats with L. infantum and/or FIV infection. [ABSTRACT FROM AUTHOR]

Canine leishmaniosis, caused by the protozoan parasite Leishmania infantum, is a cosmopolitan vector-borne zoonosis, transmitted principally by Phlebotomus perniciosus in Spain and Portugal, where it is considered an endemic disease. Ecoinformatics tools such as ecological niche models (ENM) have been successfully tested to model the distribution of the risk of infection of different parasitosis as they take into account environmental variables vital for their survival. The risk map proposed in this study combines the potential distribution of Ph. perniciosus in the Iberian Peninsula and the calculation of the infection rate of the parasite in the vector to model the risk of contracting the disease in a more realistic way. In fact, this weighting strategy improves the predictive power of the resulting model (R²  = 0.42, p = < 0.01) compared to the Ph. perniciosus ENM model alone (R²  = 0.13, p > 0.05). The places with the highest risk of transmission are the southwest and central peninsular area, as well as the Mediterranean coast, the Balearic Islands and the Ebro basin, places where the ideal habitat of Ph. perniciosus and the infection rate is also high. In the case of future projections under climate change scenarios, an increase in the risk of infection by L. infantum can be observed in most of the territory (4.5% in 2040, 71.6% in 2060 and 63% in 2080), mainly in the northern part of the peninsula. The use of ENMs and their weighting with the infection rate in Ph. perniciosus is a useful tool in predicting the risk of infection for L. infantum in dogs for a given area. In this way, a more complete model can be obtained to facilitate prevention and control. [ABSTRACT FROM AUTHOR]

Simple Summary: To treat canine leishmaniosis, two medication combinations are used: meglumine antimoniate with allopurinol, or miltefosine with allopurinol. This study compared the clinical effectiveness of both options after one month of treatment. The results showed a significantly higher rate of complete clinical cure in the meglumine antimoniate and allopurinol group. Most dogs in both groups improved after one month of treatment. There were no significant differences in the presence of the Leishmania parasite between the groups after treatment. The humoral immune response could not be compared due to insufficient data. Overall, meglumine antimoniate and allopurinol seem more effective in treating canine leishmaniosis compared to miltefosine and allopurinol. The treatment of canine leishmaniosis commonly involves meglumine antimoniate with allopurinol or miltefosine with allopurinol. This study aims to compare the clinical and clinicopathological efficacy at 28–30 days of conventional dosing regimens for both treatments using the critically appraised topic methodology. A comprehensive search across three databases (PubMed, CAB Abstracts, and Web of Science) from March 2004 to September 2023 yielded 16 relevant articles, encompassing 325 ogs treated with meglumine antimoniate and allopurinol, and 273 dogs treated with miltefosine and allopurinol. The findings indicated a significantly higher rate of complete clinical cure in the group treated with meglumine antimoniate and allopurinol. Most dogs in both groups exhibited improvement in clinicopathological alterations after one month of treatment. No significant difference was observed in the number of dogs that showed a negative Leishmania qPCR between the two groups, one month post-treatment. However, quantitative serology results were not commonly reported in the available data and therefore this aspect could not be compared. [ABSTRACT FROM AUTHOR]

Abstract Background Since the 2000’s, plants have been used as bioreactors for the transient production of molecules of interest such as vaccines. To improve protein yield, “amplicon” vectors based on plant viruses are used. These viral constructs, engineered to carry the gene of interest replicate strongly once introduced into the plant cell, allowing significant accumulation of the protein. Here, we evaluated the suitability of the monocot-infecting RNA virus Rice yellow mottle virus (RYMV) as an amplicon vector. The promastigote surface antigen (PSA) of the protozoan Leishmania was considered as a protein of interest due to its vaccine properties against canine leishmaniasis. Results Since P1 (ORF1) and CP (ORF3) proteins are not strictly necessary for viral replication, ORF1 was deleted and the PSA gene was substituted to ORF3 in the RYMV-based vector. We evaluated its expression in the best described plant bioreactor system, Nicotiana benthamiana which, unlike rice, allows transient transformation by Agrobacterium. Despite not being its natural host, we demonstrated a low level of RYMV-based vector replication in N. benthamiana leaves. Under optimized ratio, we showed that the P19 silencing suppressor in combination with the missing viral CP ORF significantly enhanced RYMV amplicon replication in N. benthamiana. Under these optimized CP/P19 conditions, we showed that the RYMV amplicon replicated autonomously in the infiltrated N. benthamiana cells, but was unable to move out of the infiltrated zones. Finally, we showed that when the RYMV amplicon was expressed under the optimized conditions we set up, it allowed enhanced PSA protein accumulation in N. benthamiana compared to the PSA coding sequence driven by the 35S promoter without amplicon background. Conclusion This work demonstrates that a non-dicot-infecting virus can be used as an amplicon vector for the efficient production of proteins of interest such as PSA in N. benthamiana leaves.

Multi-host pathogens that infect various animal species and humans are considered of great importance for public and animal health. Leishmania spp. parasites are a characteristic example of such pathogens. Although leishmaniosis in humans is endemic for about 100 countries around the world it is classified as a neglected tropical disease. There are three main forms of leishmaniosis in humans: cutaneous (CL), visceral (VL) and mucocutaneous leishmaniosis (MCL). Each year, about 30,000 new cases of VL and more than 1 million new cases of CL are recorded. In Europe L. infantum is the dominant species with dogs being reservoir hosts. Apart from dogs, infection has been recorded in various animals, which suggests that other species could play a role in the maintenance of the parasite in nature. Herein we provide an in-depth review of the literature with respect to studies that deal with Leishmania infantum infections in domestic and wild animal species in Europe. Given the fact that domesticated and wild animals could contribute to the incidences of leishmaniosis in humans, the aim of this paper is to provide a comprehensive review which could potentially be used for the development of measures when it comes to the control of the Leishmania infantum parasite. [ABSTRACT FROM AUTHOR]

Background: Since the 2000's, plants have been used as bioreactors for the transient production of molecules of interest such as vaccines. To improve protein yield, "amplicon" vectors based on plant viruses are used. These viral constructs, engineered to carry the gene of interest replicate strongly once introduced into the plant cell, allowing significant accumulation of the protein. Here, we evaluated the suitability of the monocot-infecting RNA virus Rice yellow mottle virus (RYMV) as an amplicon vector. The promastigote surface antigen (PSA) of the protozoan Leishmania was considered as a protein of interest due to its vaccine properties against canine leishmaniasis. Results: Since P1 (ORF1) and CP (ORF3) proteins are not strictly necessary for viral replication, ORF1 was deleted and the PSA gene was substituted to ORF3 in the RYMV-based vector. We evaluated its expression in the best described plant bioreactor system, Nicotiana benthamiana which, unlike rice, allows transient transformation by Agrobacterium. Despite not being its natural host, we demonstrated a low level of RYMV-based vector replication in N. benthamiana leaves. Under optimized ratio, we showed that the P19 silencing suppressor in combination with the missing viral CP ORF significantly enhanced RYMV amplicon replication in N. benthamiana. Under these optimized CP/P19 conditions, we showed that the RYMV amplicon replicated autonomously in the infiltrated N. benthamiana cells, but was unable to move out of the infiltrated zones. Finally, we showed that when the RYMV amplicon was expressed under the optimized conditions we set up, it allowed enhanced PSA protein accumulation in N. benthamiana compared to the PSA coding sequence driven by the 35S promoter without amplicon background. Conclusion: This work demonstrates that a non-dicot-infecting virus can be used as an amplicon vector for the efficient production of proteins of interest such as PSA in N. benthamiana leaves. [ABSTRACT FROM AUTHOR]

Simple Summary: Leishmania infantum is a zoonotic protozoan parasite transmitted by phlebotomine sandflies. Dogs are the main reservoir for human infections. In recent years, outbreaks of human leishmaniasis have been reported in different regions of Spain associated with the Iberian hare and European rabbit. However, there is a notable scarcity of information regarding L. infantum infection in the European hare and in Northeastern Spain where this species occurs. The present study aimed to assess Leishmania spp. exposure and infection in lagomorphs and sympatric domestic dogs in NE Spain. Results suggest a more important role for the European rabbit than the European hare in the epidemiology of this parasite in NE Spain. Given the strong correlation between lagomorph densities and human leishmaniasis outbreaks in Spain, the high rabbit and human densities in NE Spain, and the high Leishmania spp. seroprevalence in rabbits, it becomes relevant to establish surveillance programs for lagomorphs in this region. Leishmania infantum is a zoonotic protozoan parasite distributed worldwide that is transmitted by phlebotomine sandflies. Dogs are the main reservoir for human infections. However, in recent years, the capacity of lagomorphs to contribute to Leishmania transmission has been confirmed. The present study aimed to assess Leishmania spp. exposure and infection in lagomorphs and sympatric domestic dogs in NE Spain. Sera from European hares, European rabbits, and rural dogs were tested for antibodies against L. infantum using an in-house indirect ELISA. PCR analysis targeting Leishmania spp. was performed in spleens from L. europaeus. Antibodies against Leishmania spp. were detected in all the species analyzed. Total sample prevalence was significantly higher in O. cuniculus (27.9%) than in L. europaeus (2.0%). Results of the PCR were all negative. The present study expands knowledge about Leishmania infections in free-ranging lagomorphs in the Iberian Peninsula, suggesting a more important role of O. cuniculus in the study area. Given the strong correlation between lagomorph densities and human leishmaniasis outbreaks in Spain, the high rabbit and human densities in NE Spain, and the high Leishmania spp. seroprevalence in rabbits, it becomes imperative to establish surveillance programs for lagomorphs in this region. [ABSTRACT FROM AUTHOR]

Simple Summary: The erythrocyte sedimentation rate (ESR) has been increasingly used in canine medicine to assess inflammation levels. In this study, the ESR was compared to several inflammatory and immune response markers, typically investigated in dogs with canine leishmaniasis (CanL) and in dogs affected by other inflammatory conditions. Three groups of dogs were included in the study: CanL affected dogs without clinical signs (INFECTED, #25) or with clinical signs (SICK, #43), and dogs affected by acute or acute-on-chronic conditions (OTHER DISEASE, #65). The ESR and several inflammatory (i.e., C reactive protein, fibrinogen, haptoglobin, and ferritin,) or immunological parameters (i.e., total proteins, gamma-globulins, IgG, and IgM) were compared between groups and correlated. The ESR was statistically higher in the SICK group and in the OTHER DISEASE group than in the INFECTED group. ESR values may therefore help to stage the severity of CanL. In addition, as a point-of-care assay, the ESR could be used to screen the health status of dogs with its values being related to the severity of any disease. The erythrocyte sedimentation rate (ESR) has been used in canine medicine in several disorders, above all, to evaluate levels of inflammation. This study evaluated the ESR in canine leishmaniosis (CanL) and other inflammatory conditions. Three groups of dogs were examined: CanL affected dogs without clinical signs (INFECTED group, #25) or with clinical signs (SICK group, #43) and dogs affected by acute or acute-on-chronic conditions (OTHER DISEASE group, #65). The ESR was compared with acute phase proteins or reactants either positive or negative (leukogram, fibrinogen, iron, unsaturated iron binding capacity, ferritin, haptoglobin, and albumin) and immunological markers (gamma-globulins, IgG, and IgM). The ESR was higher in the SICK group than in the INFECTED group (median 39 vs. 11 mm/h; p < 0.0001), as well as in the OTHER DISEASE than in the INFECTED groups (median 41 vs. 11 mm/h; p < 0.0001). The ESR appeared outside the reference range for all dogs in the SICK and OTHER DISEASE groups and almost with similar values (mm/h; median 39, 95% CI 31–51 vs. 41, 95% CI 12–87; p > 0.05). The extent of changes in ESR can help to establish the severity of CanL and other inflammatory disorders. As a point-of-care test, the ESR can be used to screen dogs for unhealthy conditions, and its values correlate with the severity of any disease, including CanL. [ABSTRACT FROM AUTHOR]

Canine leishmaniosis, caused by the protozoan parasite Leishmania infantum, is a cosmopolitan vector-borne zoonosis, transmitted principally by Phlebotomus perniciosus in Spain and Portugal, where it is considered an endemic disease. Ecoinformatics tools such as ecological niche models (ENM) have been successfully tested to model the distribution of the risk of infection of different parasitosis as they take into account environmental variables vital for their survival. The risk map proposed in this study combines the potential distribution of Ph. perniciosus in the Iberian Peninsula and the calculation of the infection rate of the parasite in the vector to model the risk of contracting the disease in a more realistic way. In fact, this weighting strategy improves the predictive power of the resulting model (R2 = 0.42, p = 0.05). The places with the highest risk of transmission are the southwest and central peninsular area, as well as the Mediterranean coast, the Balearic Islands and the Ebro basin, places where the ideal habitat of Ph. perniciosus and the infection rate is also high. In the case of future projections under climate change scenarios, an increase in the risk of infection by L. infantum can be observed in most of the territory (4.5% in 2040, 71.6% in 2060 and 63% in 2080), mainly in the northern part of the peninsula. The use of ENMs and their weighting with the infection rate in Ph. perniciosus is a useful tool in predicting the risk of infection for L. infantum in dogs for a given area. In this way, a more complete model can be obtained to facilitate prevention and control.

Abstract Background Domperidone (Leisguard®) is an immunomodulatory drug used as a preventive measure in healthy dogs. However, no studies have been published in healthy Leishmania infantum-seropositive dogs. The aim of this study was to evaluate the clinical efficacy and safety of domperidone as immunotherapy in Leishmania-seropositive healthy dogs. Methods Sixty-seven dogs were treated with domperidone at 0.5 mg/kg and 44 dogs received placebo, once daily for 4 consecutive weeks. Monthly treatments were repeated every 4 months until the end of the 1-year follow-up period. Veterinary examinations were performed on days 0, 30, 120, 150, 240, 270 and 360. Samples of blood and urine were collected on days 0, 120, 240 and 360 for routine laboratory tests and quantitative in-house ELISA for the detection of L. infantum-specific antibodies. Furthermore, Leishmania real-time PCR and IFN-γ ELISA were performed at day 0 and the end of the study. Dogs that developed disease were withdrawn from the study and classified as sick dogs. Adverse drug reactions were reported. Results Thirty dogs developed disease during the follow-up period: 13/67 (19.4%) in the group treated with domperidone and 17/44 (38.6%) in the placebo-treated group (P = 0.03). Low-seropositive dogs treated with domperidone (4/40, 9.1%) were significantly less likely to develop disease compared to low-seropositive dogs treated with placebo (7/24, 29.2%; P = 0.04), while no differences were found between domperidone (9/23, 39.1%) and placebo (10/20, 50%) in medium- to high-seropositive dogs. At the end of the study, a higher proportion of Leishmania PCR-positive dogs was observed in the placebo-treated group (16/33, 48.5%) compared to the domperidone group (13/51, 25.5%; P = 0.04). Furthermore, low-seropositive dogs treated with domperidone with an increase of IFN-γ concentration presented a higher increase than those treated with placebo at the end of the study. Four dogs treated with domperidone presented self-limiting diarrhea. Conclusions Healthy dogs with low L. infantum antibody levels treated with domperidone were less likely to develop disease compared to placebo-treated dogs. Furthermore, domperidone presented a good safety profile. Graphical abstract

Abstract Background Canine leishmaniosis caused by Leishmania infantum is an endemic disease in Spain. The dog is considered the main reservoir, and the detection of specific serum antibodies against L. infantum antigen is the most used technique for diagnosing this infection. The LEISCAN LEISHMANIA ELISA test is a commercialized enzyme‐linked immunosorbent assay for the detection and measurement of canine anti‐Leishmania serum antibodies. Objectives The aim of this study was to assess seroprevalence results of apparently healthy dogs in different areas of Spain using LEISCAN. Methods Collection of sera from 5451 apparently healthy dogs was performed between 2020 and 2021 in different areas of Spain. Dogs were of adult age (≥12 months), were not previously diagnosed with clinical leishmaniosis or vaccinated against Leishmania and did not present clinical signs compatible with L. infantum infection. LEISCAN was performed following the manufacturer's protocol. Results The overall seroprevalence was 5.5%. The highest seroprevalences were found in the Southeast of Spain: Comunidad Valenciana (14%) and Región de Murcia (14%), whereas the lowest seroprevalences were found in Northern Spain: Galicia (1%), Navarra (2%) and Castilla y León (2%) (p‐value

The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet‐visible and Fourier‐transform infrared spectroscopy. The purity of berberine was ascertained by thin‐layer chromatography using n‐propanol‐formic acid‐water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44–49 with compact spots (diameter 0.2–0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 μm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13–1.16 and 1.40–1.71, respectively. A comparison has shown that both thin‐layer chromatography and high‐performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis. [ABSTRACT FROM AUTHOR]

Background: Domperidone (Leisguard®) is an immunomodulatory drug used as a preventive measure in healthy dogs. However, no studies have been published in healthy Leishmania infantum-seropositive dogs. The aim of this study was to evaluate the clinical efficacy and safety of domperidone as immunotherapy in Leishmania-seropositive healthy dogs. Methods: Sixty-seven dogs were treated with domperidone at 0.5 mg/kg and 44 dogs received placebo, once daily for 4 consecutive weeks. Monthly treatments were repeated every 4 months until the end of the 1-year follow-up period. Veterinary examinations were performed on days 0, 30, 120, 150, 240, 270 and 360. Samples of blood and urine were collected on days 0, 120, 240 and 360 for routine laboratory tests and quantitative in-house ELISA for the detection of L. infantum-specific antibodies. Furthermore, Leishmania real-time PCR and IFN-γ ELISA were performed at day 0 and the end of the study. Dogs that developed disease were withdrawn from the study and classified as sick dogs. Adverse drug reactions were reported. Results: Thirty dogs developed disease during the follow-up period: 13/67 (19.4%) in the group treated with domperidone and 17/44 (38.6%) in the placebo-treated group (P = 0.03). Low-seropositive dogs treated with domperidone (4/40, 9.1%) were significantly less likely to develop disease compared to low-seropositive dogs treated with placebo (7/24, 29.2%; P = 0.04), while no differences were found between domperidone (9/23, 39.1%) and placebo (10/20, 50%) in medium- to high-seropositive dogs. At the end of the study, a higher proportion of Leishmania PCR-positive dogs was observed in the placebo-treated group (16/33, 48.5%) compared to the domperidone group (13/51, 25.5%; P = 0.04). Furthermore, low-seropositive dogs treated with domperidone with an increase of IFN-γ concentration presented a higher increase than those treated with placebo at the end of the study. Four dogs treated with domperidone presented self-limiting diarrhea. Conclusions: Healthy dogs with low L. infantum antibody levels treated with domperidone were less likely to develop disease compared to placebo-treated dogs. Furthermore, domperidone presented a good safety profile. [ABSTRACT FROM AUTHOR]

Simple Summary: Allopurinol is commonly used for the treatment of canine Leishmania infections. In order to reduce the risk of xanthine urolith formation, a considerable adverse effect of allopurinol, a low purine diet is mandatory. Several dog diets are advertised as low in purine, but standardised analyses are missing. Thus, the present study analysed the purine content of such dog diets (4 purine urolith prevention diets, 2 kidney diets, 1 vegan diet, 3 low protein diets, 1 homemade diet) and 1 regular diet by high performance liquid chromatography. The results revealed differences in the purine content of the diets. The lowest purine intakes could be achieved by 2 of the urate urolith prevention diets and the homemade diet. In conclusion, awareness has to be raised when selecting diets for dogs with Leishmania infections during allopurinol treatment. Reducing the alimentary purine intake contributes to the prevention of purine (especially xanthine) urolith formation, a common adverse effect of allopurinol treatment in dogs with Leishmania infections. Analyses of the purine content are not required in order to advertise a diet as low in purine. Due to different analytical methods, data provided on purine content are barely comparable. The aim of this study was to investigate the total purine content of 12 different dog diets. For this, the purine bases adenine, guanine, xanthine, and hypoxanthine were determined by standardised high performance liquid chromatography in commercially available urinary diets (n = 4), kidney diets (n = 2), low protein diets (n = 3), 1 vegan diet, 1 regular diet for healthy adult dogs, and 1 homemade low purine diet. Total purine amounts ranged between 10.2 and 90.9 mg/100 g of dry matter. The daily purine intake calculated for a 20 kg standard dog with the analysed diets ranged between 21.9 and 174.7 mg. The lowest daily purine intakes were achieved by 2 urinary urate diets, followed by the homemade diet. Differences in the purine content of commercially available diets need to be considered. Awareness has to be raised when selecting diets for dogs with Leishmania infections during allopurinol treatment in order to minimise the risk of urolith formation. [ABSTRACT FROM AUTHOR]

Background: Canine leishmaniosis caused by Leishmania infantum is an endemic disease in Spain. The dog is considered the main reservoir, and the detection of specific serum antibodies against L. infantum antigen is the most used technique for diagnosing this infection. The LEISCAN LEISHMANIA ELISA test is a commercialized enzyme‐linked immunosorbent assay for the detection and measurement of canine anti‐Leishmania serum antibodies. Objectives: The aim of this study was to assess seroprevalence results of apparently healthy dogs in different areas of Spain using LEISCAN. Methods: Collection of sera from 5451 apparently healthy dogs was performed between 2020 and 2021 in different areas of Spain. Dogs were of adult age (≥12 months), were not previously diagnosed with clinical leishmaniosis or vaccinated against Leishmania and did not present clinical signs compatible with L. infantum infection. LEISCAN was performed following the manufacturer's protocol. Results: The overall seroprevalence was 5.5%. The highest seroprevalences were found in the Southeast of Spain: Comunidad Valenciana (14%) and Región de Murcia (14%), whereas the lowest seroprevalences were found in Northern Spain: Galicia (1%), Navarra (2%) and Castilla y León (2%) (p‐value <0.001). Conclusions: In conclusion, the seroprevalence for L. infantum in apparently healthy dogs in Spain varied from almost no infection to being over 10%. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to understand the role of neutrophils in canine leishmaniosis (CanL) by assessing neutrophil activation and its relationship with different states of Leishmania infantum infection and antibody and IFN-γ production. The results showed that sick dogs in stage I-mild disease had significantly higher neutrophil activation compared to healthy seronegative and seropositive dogs and sick dogs in advanced stages (II, III–IV). Healthy seropositive dogs exhibited higher neutrophil activation compared to all other groups except sick dogs in stage I. Dogs in advanced disease stages (II, III–IV) did not show significant differences in neutrophil activation compared to healthy seronegative dogs. Furthermore, dogs in stage I had significantly higher IFN-γ concentrations compared to healthy seronegative and sick dogs in advanced disease stages. Dogs in stage II showed higher IFN-γ concentrations compared to healthy seronegative dogs, while no significant differences were observed in dogs in stage III–IV. Healthy seropositive dogs had elevated IFN-γ concentrations compared to healthy seronegative dogs and dogs in stage III–IV. These findings indicate that neutrophil activation is predominant in dogs with mild disease and healthy seropositive dogs with an association with potent IFN-γ production. This study aimed to investigate the role of neutrophils in canine leishmaniosis by assessing neutrophil activation and its relationship with different states of L. infantum infection and antibody and IFN-γ production. Dogs were categorized into five groups: healthy-seronegative (n = 25), healthy-seropositive (n = 21), LeishVet-stage I (n = 25), Leishvet-stage II (n = 41), and LeishVet-stage III–IV (n = 16). Results of the nitroblue tetrazolium reduction test (NBT) showed significantly higher neutrophil activation in stage I (median:17.17, range: [7.33–31.50]%) compared to in healthy-seronegative (4.10 [1.20–18.00]%), healthy-seropositive (7.65 [3.98–21.74]%), stage II (6.50 [1.50–28.70]%), and stage III–IV (7.50 [3.00–16.75]%) groups (p < 0.0001). Healthy-seropositive dogs also displayed higher values than all groups except stage I. Stages II and III–IV did not show significant differences compared to healthy-seronegative. Regarding IFN-γ, stage I dogs had higher concentrations (median:127.90, range: [0–3998.00] pg/mL) than healthy-seronegative (0 [0–109.50] pg/mL) (p = 0.0002), stage II (9.00 [0–5086.00] pg/mL) (p = 0.045), and stage III–IV (3.50 [80.00–548.80] pg/mL) (p = 0.02) dogs. Stage II dogs showed increased IFN-γ compared to healthy-seronegative dogs (p = 0.015), while stage III–IV dogs had no significant differences compared to healthy-seronegative dogs (p = 0.12). Healthy-seropositive dogs had elevated IFN-γ concentrations compared to healthy-seronegative dogs (p = 0.001) and dogs in stage III–IV (p = 0.03). In conclusion, neutrophil activation was higher in dogs with mild disease and healthy-seropositive dogs, and a relationship between neutrophil activation and the production of IFN-γ was found. [ABSTRACT FROM AUTHOR]

The treatment of canine leishmaniosis commonly involves meglumine antimoniate with allopurinol or miltefosine with allopurinol. This study aims to compare the clinical and clinicopathological efficacy at 28–30 days of conventional dosing regimens for both treatments using the critically appraised topic methodology. A comprehensive search across three databases (PubMed, CAB Abstracts, and Web of Science) from March 2004 to September 2023 yielded 16 relevant articles, encompassing 325 ogs treated with meglumine antimoniate and allopurinol, and 273 dogs treated with miltefosine and allopurinol. The findings indicated a significantly higher rate of complete clinical cure in the group treated with meglumine antimoniate and allopurinol. Most dogs in both groups exhibited improvement in clinicopathological alterations after one month of treatment. No significant difference was observed in the number of dogs that showed a negative Leishmania qPCR between the two groups, one month post-treatment. However, quantitative serology results were not commonly reported in the available data and therefore this aspect could not be compared.

Leishmania infantum is a zoonotic protozoan parasite distributed worldwide that is transmitted by phlebotomine sandflies. Dogs are the main reservoir for human infections. However, in recent years, the capacity of lagomorphs to contribute to Leishmania transmission has been confirmed. The present study aimed to assess Leishmania spp. exposure and infection in lagomorphs and sympatric domestic dogs in NE Spain. Sera from European hares, European rabbits, and rural dogs were tested for antibodies against L. infantum using an in-house indirect ELISA. PCR analysis targeting Leishmania spp. was performed in spleens from L. europaeus. Antibodies against Leishmania spp. were detected in all the species analyzed. Total sample prevalence was significantly higher in O. cuniculus (27.9%) than in L. europaeus (2.0%). Results of the PCR were all negative. The present study expands knowledge about Leishmania infections in free-ranging lagomorphs in the Iberian Peninsula, suggesting a more important role of O. cuniculus in the study area. Given the strong correlation between lagomorph densities and human leishmaniasis outbreaks in Spain, the high rabbit and human densities in NE Spain, and the high Leishmania spp. seroprevalence in rabbits, it becomes imperative to establish surveillance programs for lagomorphs in this region.

The erythrocyte sedimentation rate (ESR) has been used in canine medicine in several disorders, above all, to evaluate levels of inflammation. This study evaluated the ESR in canine leishmaniosis (CanL) and other inflammatory conditions. Three groups of dogs were examined: CanL affected dogs without clinical signs (INFECTED group, #25) or with clinical signs (SICK group, #43) and dogs affected by acute or acute-on-chronic conditions (OTHER DISEASE group, #65). The ESR was compared with acute phase proteins or reactants either positive or negative (leukogram, fibrinogen, iron, unsaturated iron binding capacity, ferritin, haptoglobin, and albumin) and immunological markers (gamma-globulins, IgG, and IgM). The ESR was higher in the SICK group than in the INFECTED group (median 39 vs. 11 mm/h; p < 0.0001), as well as in the OTHER DISEASE than in the INFECTED groups (median 41 vs. 11 mm/h; p < 0.0001). The ESR appeared outside the reference range for all dogs in the SICK and OTHER DISEASE groups and almost with similar values (mm/h; median 39, 95% CI 31–51 vs. 41, 95% CI 12–87; p > 0.05). The extent of changes in ESR can help to establish the severity of CanL and other inflammatory disorders. As a point-of-care test, the ESR can be used to screen dogs for unhealthy conditions, and its values correlate with the severity of any disease, including CanL.

Visceral leishmaniosis is one recent example of a global illness that demands our best efforts at understanding. Thus, mathematical modeling may be utilized to learn more about and make better epidemic forecasts. By taking into account the Caputo and Caputo-Fabrizio derivatives, a frictional model of visceral leishmaniosis was mathematically examined based on real data from Gedaref State, Sudan. The stability analysis for Caputo and Caputo-Fabrizio derivatives is analyzed. The suggested ordinary and fractional differential mathematical models are then simulated numerically. Using the Adams-Bashforth method, numerical simulations are conducted. The results demonstrate that the Caputo-Fabrizio derivative yields more precise solutions for fractional differential equations. [ABSTRACT FROM AUTHOR]

Simple Summary: Shelter dogs are considered more susceptible to infection with Leishmania infantum than domestic dogs due to the living conditions they are subjected to. These two populations of dogs were compared in an area where leishmaniosis is endemic, and shelter dogs were found to be less infected than domestic dogs. Statistically significant differences were also found between age groups and clinical statuses. Monitoring, preventing, and treating canine leishmaniosis is crucial in reducing this zoonosis among animals and humans, under the scope of One Health. Canine leishmaniosis (CanL) is a chronic, systemic, and often severe disease. The main causative agent of CanL is a protozoan parasite, Leishmania infantum, with phlebotomine sand flies acting as vectors. In Europe and other continents, L. infantum is also responsible for leishmaniosis in other animals, such as cats, horses, and humans. In Portugal, animal and human leishmaniosis is endemic, and high prevalence levels of infections and disease have been reported in dogs. There is a prejudice against stray animals and also those housed in shelters, assuming they have higher levels of infection with vector-borne pathogens, including L. infantum, when compared to domestic animals. In northeastern Portugal, serum samples were obtained from March to May 2022 in three shelters (n = 179) and thirteen veterinary clinics (n = 164), resulting in 343 dogs being analyzed for antibodies to Leishmania spp. by the direct agglutination test (DAT). The overall seroprevalence was 9.9%, with 15.2% seroprevalence in domestic dogs and 5.0% in the shelter ones (p = 0.003). The fact that shelter dogs had a lower seroprevalence could be explained by more regular veterinary care provided in shelters regarding preventive measures, including insecticides with an antifeeding effect, in comparison with domestic dogs. [ABSTRACT FROM AUTHOR]

Papular dermatitis is a cutaneous manifestation of canine Leishmania infantum infection associated with mild disease. Although it is a typical presentation, nowadays, there is still no established treatment. This study evaluated the safety and clinical efficacy of local meglumine antimoniate, locally administered polyhexamethylene biguanide (PHMB) alone or PHMB in combination with a Toll-like receptor 4 agonist (TLR4a) for the treatment of papular dermatitis due to L. infantum and assessed parasitological and immunological markers in this disease. Twenty-eight dogs with papular dermatitis were divided randomly into four different groups; three of them were considered treatment groups: PHMB (n = 5), PHMB + TLR4a (n = 4), and meglumine antimoniate (n = 10)), and the remaining were considered the placebo group (n = 9), which was further subdivided into two sub-groups: diluent (n = 5) and TLR4a (n = 4). Dogs were treated locally every 12 h for four weeks. Compared to placebo, local administration of PHMB (alone or with TLR4a) showed a higher tendency towards resolution of papular dermatitis due to L. infantum infection at day 15 (χ2 = 5.78; df = 2, p = 0.06) and day 30 (χ2 = 4.; df = 2, p = 0.12), while local meglumine antimoniate administration demonstrated the fastest clinical resolution after 15 (χ2 = 12.58; df = 2, p = 0.002) and 30 days post-treatment (χ2 = 9.47; df = 2, p = 0.009). Meglumine antimoniate showed a higher tendency towards resolution at day 30 when compared with PHMB (alone or with TLR4a) (χ2 = 4.74; df = 2, p = 0.09). In conclusion, the local administration of meglumine antimoniate appears to be safe and clinically efficient for the treatment of canine papular dermatitis due to L. infantum infection. [ABSTRACT FROM AUTHOR]

Marine Cyanobacteria (blue-green algae) have been shown to possess an enormous potential to produce structurally diverse natural products that exhibit a broad spectrum of potent biological activities, including cytotoxic, antifungal, antiparasitic, antiviral, and antibacterial activities. Here, we report the isolation and structure determination of palstimolide A, a complex polyhydroxy macrolide with a 40-membered ring that was isolated from a tropical marine cyanobacterium collected at Palmyra Atoll. NMR-guided fractionation in combination with MS2-based molecular networking and isolation via HPLC yielded 0.7 mg of the pure compound. The small quantity isolated along with the presence of significant signal degeneracy in both the 1H and 13C-NMR spectra complicated the structure elucidation of palstimolide A. Various NMR experiments and solvent systems were employed, including the LRHSQMBC experiment that allows the detection of long-range 1H-13C correlation data across 4-, 5-, and even 6-bonds. This expanded NMR data set enabled the elucidation of the palstimolide's planar structure, which is characterized by several 1,5-disposed hydroxy groups as well as a tert-butyl group. The compound showed potent antimalarial activity with an IC50 of 223 nM as well as interesting anti-leishmanial activity with an IC50 of 4.67 µM.

Comprehensive profiling of serum proteome provides valuable clues of health status and pathophysiological processes, making it the main strategy in biomarker discovery. However, the high dynamic range significantly decreases the number of detectable proteins, obstructing the insights into the underlying biological processes. To circumvent various serum enrichment methods, obtain high-quality proteome wide information using the next-generation proteomic, and study host response in canine leishmaniosis, we applied data-independent acquisition mass spectrometry (DIA-MS) for deep proteomic profiling of clinical samples. The non-depleted serum samples of healthy and naturally Leishmania-infected dogs were analyzed using the label-free 60-min gradient sequential window acquisition of all theoretical mass spectra (SWATH-MS) method. As a result, we identified 554 proteins, 140 of which differed significantly in abundance. Those were included in lipid metabolism, hematological abnormalities, immune response, and oxidative stress, providing valuable information about the complex molecular basis of the clinical and pathological landscape in canine leishmaniosis. Our results show that DIA-MS is a method of choice for understanding complex pathophysiological processes in serum and serum biomarker development. [ABSTRACT FROM AUTHOR]

This document is an erratum for an article titled "Analysis of the current risk of Leishmania infantum transmission for domestic dogs in Spain and Portugal and its future projection in climate change scenarios." The erratum corrects a production error in the order of Figures 5 and 6, which were swapped incorrectly. The publisher apologizes for the mistake and the original article has been updated. The article focuses on the risk of Leishmania infantum transmission in domestic dogs in Spain and Portugal and its future projection in climate change scenarios. [Extracted from the article]

Background: Wolbachia is a Gram-negative endosymbiont associated with several species of arthropods and filarioid nematodes, including Dirofilaria immitis. This endosymbiont may elicit a Th1 response, which is a component of the immunity against Leishmania infantum. Methods: To investigate the interactions between Wolbachia of D. immitis and L. infantum in naturally infected dogs and cytokine circulation, dogs without clinical signs (n = 187) were selected. Dogs were tested for microfilariae (mfs) by Knott, for female antigens of D. immitis by SNAP, and for anti-L. infantum antibodies by IFAT and assigned to four groups. Dogs of group 1 (G1) and 2 (G2) were positive for D. immitis and positive or negative to L. infantum, respectively. Dogs of group 3 (G3) and 4 (G4) were negative to D. immitis and positive or negative to L. infantum, respectively. Wolbachia and L. infantum DNA was quantified by real-time PCR (qPCR) in dog blood samples. A subset of dogs (n = 65) was examined to assess pro- and anti-inflammatory cytokine production using an ELISA test. Results: Of 93 dogs positive to D. immitis with circulating mfs, 85% were positive to Wolbachia, with the highest amount of DNA detected in G1 and the lowest in dogs with low mfs load in G1 and G2. Among dogs positive to L. infantum, 66% from G1 showed low antibody titer, while 48.9% from G3 had the highest antibody titer. Of 37 dogs positive to Wolbachia from G1, 26 (70.3%) had low antibody titers to L. infantum (1:160). Among cytokines, TNFα showed the highest mean concentration in G1 (246.5 pg/ml), IFNγ being the one most represented (64.3%). IL-10 (1809.5 pg/ml) and IL-6 (123.5 pg/ml) showed the highest mean concentration in dogs from G1. A lower percentage of dogs producing IL-4 was observed in all groups examined, with the highest mean concentration (2794 pg/ml) recorded in G2. Conclusion: Results show the association of D. immitis and Wolbachia with the lower antibody titers of L. infantum in co-infected dogs, suggesting the hypothesis that the endosymbiont may affect the development of the patent leishmaniosis. However, due to the limitations associated with the heterogeneity of naturally infected dogs in field conditions, results should be validated by investigation on experimental models. [ABSTRACT FROM AUTHOR]

Introduction. Sandflies are vectors of leishmaniasis. Ecological niche models are currently used to infer the distribution of species in a given geographic area. So far, there is no evidence on the inference of ecological niche fragmentation in sandflies. Objective. Our objective is to implement landscape indices for the interpretation of the fragmentation of the ecological niche in three species of sandflies in Central and South America. Material and methods. Ecological niche models were built for three species of sandflies in Central and South America in three time periods: past (Pleistocene), present and future (RCP 8.5). Finally, we used FragStat analysis to calculate two indices: COHESION and CPLAND. Results. Our results show a COHESION index higher than 99.8%; while the values of CPLAND were increasing from 3.4-72.1% depending on the species and the period. Conclusion. Ecological connectivity between the patches of the projected geographic distribution of the ecological niche model was verified among the three species of sandflies in Central and South America. [ABSTRACT FROM AUTHOR]

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Mammaliicoccus (Staphylococcus) sciuri has been rarely associated with infections and sepsis in humans. A 3‐month‐old male western lowland gorilla (Gorilla gorilla gorilla), born under human care, died after a traumatic event. Histologic, microbiologic, and molecular findings in postmortem demonstrated a suppurative meningoencephalitis and bacteremia associated with M. sciuri infection. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: Mesenchymal stem cells (MSCs) are mesodermal-origin postnatal stem cells that are able to self-renew and differentiate into several cell lineages. MSCs possess anti-inflammatory and anti-apoptotic activity, immunomodulatory action, as well as regenerative properties. Since MSCs also have antimicrobial properties, it has been suggested that they should be utilized for treating infectious diseases. In this study, the last pre-clinical advances in the efficacy of MSCs' therapy against parasitic diseases were reviewed. Methods: Data about the effects of MSCs' therapy on experimental and pre-clinical parasitic infections were collected by searching relevant articles and reviewing them. Results: In the present study, empirical findings on the impacts of MSCs' therapy against parasitic diseases were recapitulated. Studies have reported that the administration of MSCs reduces the burden of the parasite and modulates the levels of inflammatory and anti-inflammatory cytokines in parasitic diseases, including schistosomiasis, malaria, cystic echinococcosis, toxocariasis, leishmaniasis, and trypanosomiasis. Also, the administration of MSCs combined with anti-parasitic drugs enhanced anti-parasitic effects and immunomodulatory actions. Conclusion: Based on this review, empirical studies have revealed the beneficial effects of MSCs against some parasitic infections. This new therapeutic strategy showed both anti-parasitic and immunomodulatory effects. Also, the combination of anti-parasitic drugs with MSCs' therapy promoted anti-parasitic and immunomodulatory activities against parasitic infections. [ABSTRACT FROM AUTHOR]

Abstract Background Canine leishmaniosis caused by the protozoan Leishmania infantum is a complex infection due to its variable clinical signs and laboratory findings. Therefore, a broad range of techniques is available for diagnosis. Testing for specific antibodies in serum is the most commonly used technique, although the testing of other body fluids, such as oral transudate (OT), can be an alternative as its collection is non-invasive and testing can be performed by untrained personnel. The aim of this study was to assess and compare the detection of L. infantum-specific antibodies in paired samples of serum and OT collected from apparently healthy dogs and dogs with clinical leishmaniosis using an in-house enyzme-linked immunosorbent assay (ELISA). Methods Serum and OT were collected from 407 dogs, which varied in breed, sex, age, lifestyle and clinical status, by many practicing veterinarians in Spain. The main geographical areas of sampling included Barcelona (n = 110), Mallorca (n = 94), Cadiz (n = 54) and Asturias (n = 47). The majority of infected dogs were apparently healthy (89.9%) while 41 presented clinical signs and/or clinicopathological abnormalities compatible with L. infantum infection and subsequently diagnosed with leishmaniosis (10.1%). An in-house ELISA was performed to quantify the anti-Leishmania antibodies in serum and OT. Results The L. infantum infection rate determined by the in-house ELISA was 37.1% in serum samples and 32.7% in OT samples. Serum and OT ELISA results showed a positive correlation (Spearman's correlation coefficient r s = 0.6687, P

Abstract Background There are several screening tools for detecting Leishmania infantum infection in dogs and various preventive measures to protect against it. Some studies have investigated them, but not many have described their current use. The aim of this study was to investigate which preventive measures and serological screening tools for L. infantum infection were employed from 2012 to 2018 in dogs from different endemic European countries. Methods A set of electronic datasheets was completed for each dog from several veterinary centres. Classification of preventive measures included: (1) repellents, (2) vaccines and (3) immunomodulators. Classification of serological tests included the: (1) direct agglutination test (DAT), (2) enzyme-linked immunosorbent assay (ELISA), (3) indirect immunofluorescence (IFI), (4) rapid tests and (5) other assays. Dogs were also classified depending on their risk of exposure and living area. Results Information from 3762 dogs was gathered. Preventive measures were applied in 91.5% of dogs and the most frequently used were repellents (86.2%) followed by vaccines (39.8%) and Leisguard® (15.3%). The different types of repellents (collar and spot-on) were used similarly. A combination of a vaccine and repellents was preferred in the high-risk group while the low-risk preferred a combination of Leisguard® and a repellent (Chi-square test: X 2 = 88.41, df = 10, P

Abstract Background Feline leishmaniosis caused by Leishmania infantum is often associated with feline immunodeficiency virus (FIV) infection; however, the role and clinical significance of this coinfection remain unknown. This study aimed to assess whether FIV is associated with L. infantum infection in cats from canine leishmaniosis endemic areas and to report the clinical signs and hematological alterations associated with coinfection. Methods A retrospective matched case-control study (ratio 1:2) was conducted. Data of clinical examination and complete blood count (CBC) were selected from a cohort of 705 cats examined for epidemiological studies on feline leishmaniosis conducted between 2012 and 2019. Ninety-one FIV seropositive cases and 182 FIV seronegative control cats were selected. Matching was done according to age, sex, lifestyle and geographic provenience of case cats. Rapid ELISA devices were mainly used to detect anti-FIV antibodies. Anti-Leishmania IgG antibodies were detected by indirect-immunofluorescence test (IFAT). Leishmania DNA was searched in blood, oral and conjunctival swabs by quantitative real-time PCR. Results Feline immunodeficiency virus seropositive cats had no hematological abnormalities suggestive of an advanced stage of FIV infection and were statistically more frequently IFAT positive, and their risk of being L. infantum antibody positive was 2.8 greater than in the FIV seronegatives. The association of FIV seropositivity with L. infantum antibody positivity was confirmed in the univariable model of logistic regression. A multivariate model found FIV infection and L. infantum PCR positivity as predictors of a positive L. infantum IFAT result. Male outdoor cats from rural or suburban areas were at risk for FIV and L. infantum antibody positivity. Clinical signs more frequently associated with the coinfection were oral lesions, pale mucous membranes and low body condition score (BCS). Conclusions This study documents that FIV seropositive cats with no hematological abnormalities suggestive of an advanced stage of FIV infection are more prone to be L. infantum seroreactive by IFAT in endemic areas. Therefore, FIV seropositive cats should be tested for L. infantum antibodies and treated for preventing sand fly bites. Pale mucous membranes, low BCS and oral lesions but no CBC abnormalities were significantly associated with the coinfection. Graphical abstract

Reducing the alimentary purine intake contributes to the prevention of purine (especially xanthine) urolith formation, a common adverse effect of allopurinol treatment in dogs with Leishmania infections. Analyses of the purine content are not required in order to advertise a diet as low in purine. Due to different analytical methods, data provided on purine content are barely comparable. The aim of this study was to investigate the total purine content of 12 different dog diets. For this, the purine bases adenine, guanine, xanthine, and hypoxanthine were determined by standardised high performance liquid chromatography in commercially available urinary diets (n = 4), kidney diets (n = 2), low protein diets (n = 3), 1 vegan diet, 1 regular diet for healthy adult dogs, and 1 homemade low purine diet. Total purine amounts ranged between 10.2 and 90.9 mg/100 g of dry matter. The daily purine intake calculated for a 20 kg standard dog with the analysed diets ranged between 21.9 and 174.7 mg. The lowest daily purine intakes were achieved by 2 urinary urate diets, followed by the homemade diet. Differences in the purine content of commercially available diets need to be considered. Awareness has to be raised when selecting diets for dogs with Leishmania infections during allopurinol treatment in order to minimise the risk of urolith formation.

This study aimed to investigate the role of neutrophils in canine leishmaniosis by assessing neutrophil activation and its relationship with different states of L. infantum infection and antibody and IFN-γ production. Dogs were categorized into five groups: healthy-seronegative (n = 25), healthy-seropositive (n = 21), LeishVet-stage I (n = 25), Leishvet-stage II (n = 41), and LeishVet-stage III–IV (n = 16). Results of the nitroblue tetrazolium reduction test (NBT) showed significantly higher neutrophil activation in stage I (median:17.17, range: [7.33–31.50]%) compared to in healthy-seronegative (4.10 [1.20–18.00]%), healthy-seropositive (7.65 [3.98–21.74]%), stage II (6.50 [1.50–28.70]%), and stage III–IV (7.50 [3.00–16.75]%) groups (p < 0.0001). Healthy-seropositive dogs also displayed higher values than all groups except stage I. Stages II and III–IV did not show significant differences compared to healthy-seronegative. Regarding IFN-γ, stage I dogs had higher concentrations (median:127.90, range: [0–3998.00] pg/mL) than healthy-seronegative (0 [0–109.50] pg/mL) (p = 0.0002), stage II (9.00 [0–5086.00] pg/mL) (p = 0.045), and stage III–IV (3.50 [80.00–548.80] pg/mL) (p = 0.02) dogs. Stage II dogs showed increased IFN-γ compared to healthy-seronegative dogs (p = 0.015), while stage III–IV dogs had no significant differences compared to healthy-seronegative dogs (p = 0.12). Healthy-seropositive dogs had elevated IFN-γ concentrations compared to healthy-seronegative dogs (p = 0.001) and dogs in stage III–IV (p = 0.03). In conclusion, neutrophil activation was higher in dogs with mild disease and healthy-seropositive dogs, and a relationship between neutrophil activation and the production of IFN-γ was found.