Discovery of essential kinetoplastid-insect adhesion proteins and their function in Leishmania-sand fly interactions.

Leishmania species, members of the kinetoplastid parasites, cause leishmaniasis, a neglected tropical disease, in millions of people worldwide. Leishmania has a complex life cycle with multiple developmental forms, as it cycles between a sand fly vector and a mammalian host; understanding their life cycle is critical to understanding disease spread. One of the key life cycle stages is the haptomonad form, which attaches to insect tissues through its flagellum. This adhesion, conserved across kinetoplastid parasites, is implicated in having an important function within their life cycles and hence in disease transmission. Here, we discover the kinetoplastid-insect adhesion proteins (KIAPs), which localise in the attached Leishmania flagellum. Deletion of these KIAPs impairs cell adhesion in vitro and prevents Leishmania from colonising the stomodeal valve in the sand fly, without affecting cell growth. Additionally, loss of parasite adhesion in the sand fly results in reduced physiological changes to the fly, with no observable damage of the stomodeal valve and reduced midgut swelling. These results provide important insights into a comprehensive understanding of the Leishmania life cycle, which will be critical for developing transmission-blocking strategies.

Overview and Approaches for Handling of Animal Models of Leishmaniasis.

Leishmaniasis, a disease of global relevance, results from infection with the protozoan parasite, Leishmania, which is transmitted to susceptible hosts through the bite of sand flies. Multiple forms of leishmaniasis may occur, including cutaneous, mucocutaneous, and visceral. Research with animal models remains an important approach to help define basic pathophysi- ologic processes associated with infection and disease. In this regard, mice and hamsters represent the most commonly used models. The severity of leishmaniasis in animal models depends on several factors, including genotype of the host and parasite and the dose and route of administration of the parasite to the host, and severity of outcome may range from subclinical to severe illness. This review provides basic background on leishmaniasis, relevant animal models, the pathophysiology and clinical signs in animals used as models of leishmaniasis, and general approaches to mitigate risk to personnel.

Phlebotomine sand fly distribution and abundance in France: A systematic review.

Global changes in climate are contributing to modified Phlebotomine sand fly presence and activity, and the distribution of the pathogens they transmit (e.g., Leishmania and Phlebovirus), and are leading to their possible extension toward northern France. To predict the evolution of these pathogens and control their spread, it is essential to identify and characterize the presence and abundance of potential vectors. However, there are no recent publications describing sand fly species distribution in France. Consequently, we carried out a systematic review to provide distribution and abundance maps over time, along with a simplified dichotomous key for species in France. The review adhered to PRISMA guidelines, resulting in 172 relevant capture reports from 168 studies out of the 2646 documents retrieved, of which 552 were read and 228 analyzed. Seven species were recorded and categorized into three groups based on their abundance: low abundance species, abundant but little-studied species, and abundant vector species. Sand flies are certainly present throughout France but there is a greater diversity of species in the Mediterranean region. Phlebotomus perniciosus and Ph. ariasi are the most abundant and widely distributed species, playing a role as vectors of Leishmania. Sergentomyia minuta, though very abundant, remains under-studied, highlighting the need for further research. Phlebotomus papatasi, Ph. perfiliewi, Ph. sergenti, and Ph. mascittii are present in low numbers and are less documented, limiting understanding of their potential role as vectors. This work provides the necessary basis for comparison of field data generated in the future.

Title: Répartition et abondance des phlébotomes en France : revue systématique. Abstract: Les changements globaux du climat contribuent à modifier la présence et l'activité des phlébotomes, ainsi que la répartition des pathogènes qu'ils transmettent (par exemple Leishmania et Phlebovirus), et conduisent à leur éventuelle extension vers le nord de la France. Pour prédire l'évolution de ces pathogènes et contrôler leur propagation, il est essentiel d'identifier et de caractériser la présence et l'abondance des vecteurs potentiels. Il n'existe cependant aucune publication récente décrivant la répartition des espèces de phlébotomes en France. Par conséquent, nous avons réalisé une revue systématique pour fournir des cartes de répartition et d'abondance dans le temps, ainsi qu'une clé dichotomique simplifiée pour les espèces françaises. La revue a respecté les lignes directrices PRISMA, aboutissant à 172 rapports de capture pertinents provenant de 168 études sur les 2 646 documents récupérés, dont 552 ont été lus et 228 analysés. Sept espèces ont été recensées et classées en trois groupes en fonction de leur abondance : les espèces de faible abondance, les espèces abondantes mais peu étudiées et les espèces vectrices abondantes. Les phlébotomes sont certes présents partout en France mais on trouve une plus grande diversité d'espèces dans le bassin méditerranéen. Phlebotomus perniciosus et Ph. ariasi sont les espèces les plus abondantes et les plus largement réparties, jouant un rôle de vecteurs de Leishmania. Sergentomyia minuta, bien que très abondant, reste sous-étudié, ce qui souligne la nécessité de recherches plus approfondies. Phlebotomus papatasi, Ph. perfiliewi, Ph. sergenti et Ph. mascittii sont présents en faibles nombres et sont moins documentés, ce qui limite la compréhension de leur rôle potentiel en tant que vecteurs. Ce travail fournit la base nécessaire pour la comparaison des données de terrain générées à l'avenir.

Educational WhatsApp-delivered intervention based on social cognitive theory to promote leishmaniosis preventive behavior of health ambassadors: a randomized controlled trial.

BACKGROUND: Multidimensional strategies can promote preventive behaviors to prevent cutaneous leishmaniosis. WhatsApp, the popular messenger of Iranians, can be used as a platform to provide health education interventions. This study aimed to investigate the effect of using an educational intervention in WhatsApp based on social cognitive theory (SCT) on the preventive behaviors of health ambassadors. METHODS: A randomized clinical trial was conducted from September 2020 to April 2021 on 220 people living in endemic areas of leishmaniosis in Mashhad Province, Iran. By the cluster method sampling, the samples were randomly divided into two intervention and control groups. The intervention was performed for the intervention group over two weeks. Data were collected using a researcher-made questionnaire based on the constructs of SCT before and after the intervention. SPSS 16 was implemented to test multiple statistical analyses. RESULTS: Findings from the intervention group compared with the control group showed that the scores of SCT constructs and preventive behaviors were significantly changed (P < 0.001) across time during baseline through follow-up. These changes were not significant in the control group. CONCLUSIONS: The educational intervention based on the SCT model to promote leishmaniosis preventive behaviors is effective. This intervention module can be tested in other targeted populations in endemic areas to prevent and control leishmaniosis. TRIAL REGISTRATION: Iranian Registry of Clinical Trials Registry IRCT20200615047784N1, registered 02/09/2020.

Veterinary perspectives on the urbanization of leishmaniosis in Morocco.

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.

Sergentomyia khawi: a potential vector for Leishmania and Trypanosoma parasites affecting humans and animals and insecticide resistance status in endemic areas of Songkhla, southern Thailand.

BACKGROUND: Sand flies serve as crucial vectors in various medical and veterinary diseases. Sand fly-borne diseases pose a significant public health burden globally, as the causative agents can infect a diverse range of hosts, leading to severe consequences such as leishmaniasis and sand fly fever. Additionally, the widespread use of insecticides for agricultural purposes and mosquito control is not specifically targeted at sand flies, potentially leading to resistance development. We investigated sand fly species, their potential role as vectors of various parasitic agents, and insecticide resistance in the endemic regions of Natawi and Sadao districts in Songkhla, Thailand. METHODS: Sand flies were collected using CDC light traps. The collected sand flies were then identified to species level using molecular techniques. Subsequent analyses included the detection of pathogens and the identification of pyrethroid resistance mutations within the voltage-sensitive sodium channel (Vgsc) domain IIS6 gene, followed by sequence analysis. RESULTS: The study identified nine sand fly species belonging to the genera Phlebotomus and Sergentomyia. The DNA of Sergentomyia khawi was the only species found to test positive for one sample of Leishmania orientalis in Sadao district. This finding represents the first detection of L. orientalis in Thailand. Moreover, three samples of Leishmania martiniquensis and four samples of Trypanosoma sp. were found in the Natawi district. No I1011M, L1014F/S, V1016G, or F1020S mutations were detected in Vgsc gene. CONCLUSIONS: The results of this study provide valuable information on sand fly species and the continuous circulation of Leishmania spp. and Trypanosoma spp. in Songkhla, southern Thailand. Moreover, the development of geo-spatial information on vectors, parasites, and insecticide resistance in sand flies has the potential to provide well-informed risk assessments and evidence-based guidance for targeted vector control in Thailand. These results can serve as a foundation for integrating the One Health approach, which is crucial for disease control, considering the diverse ecological interactions among human and/or animal reservoir hosts, parasites, and sand fly vectors.

Fauna and seasonality of sand flies (Diptera: Psychodidae: Phlebotominae) from a leishmaniasis transmission area in the central region of Rio Grande do Sul, Brazil.

Sand flies, vectors capable of transmitting Leishmania spp. and causing leishmaniasis, have been a concern in the central region of Rio Grande do Sul, where canine leishmaniasis (CanL) has been documented since 1985. Notably, there has been a surge in CanL cases since 2017, with two autochthonous cases of human visceral leishmaniasis reported in the area in 2021. This study aimed to identify the sand fly fauna potentially involved in disease transmission. Modified Centers for Disease Control light traps were deployed in three neighborhoods of the city where CanL cases had been previously reported, spanning January 2021 to December 2022. Of the 89 collections conducted, 119 sand flies belonging to five species were captured: Pintomyia fischeri (76/119, 63.86%), Migonemyia migonei (23/119, 19.33%), Lutzomyia longipalpis (16/119, 13.45%), Brumptomyia sp. (2/119, 1.68%), and Psathyromyia lanei (2/119, 1.68%), predominantly between February and April in 2021 and 2022. Polymerase chain reaction testing on all female specimens yielded negative results for Leishmania spp. DNA. Although Leishmania spp. was not detected in these vectors, these findings underscore the imperative to implement measures aimed at curtailing the proliferation of these insects.

Phlebotomine (Diptera: Psychodidae) species and their blood meal sources in a new leishmaniasis focus in Los Montes de María, Bolívar, in northern Colombia / Especies de flebotomíneos y sus fuentes de ingesta sanguínea en un nuevo foco de leishmaniasis en Los Montes de María (Bolívar) al norte de Colombia.

Introduction. El Alférez, a village in Los Montes de María (Bolívar, Colombia) and a macro-focus of leishmaniasis, recorded its first case in 2018, evidencing changes in the distribution and eco-epidemiology of the disease, although interactions between vectors and local fauna remain unknown. Objective. To evaluate the diversity of sandflies and their blood meal sources in the community of El Alférez in the municipality of El Carmen de Bolívar (Bolívar, Colombia). Materials and methods. In 2018, sandflies were collected using LED-based light traps in domestic, peridomestic, and sylvatic ecotopes and identified at the species level. Multiplex polymerase chain reaction targeting the mitochondrial cytochrome B gene was used to analyze blood from the digestive tract. Results. Lutzomyia evansi was the most abundant species (71.85%; n = 485/675), followed by Lu. panamensis, Lu. gomezi, Lu. trinidadensis, Lu. dubitans, Lu. abonnenci, and Lu.aclydifera. Twenty-five percent of the species had blood meals from Canis familiaris (36.00%; n = 9/25), Ovis aries (36.00%; n=9:/25), Bos taurus (24.00%; n = 6/25), Sus scrofa (20.00%; n = 5/25), and Homo sapiens (8.00%; n = 2/25). Lutzomyia evansi registered the highest feeding frequency (68.00%; n = 17/25), predominantly on a single (44.00%; n = 11/25) or multiple species (24.00%; n = 6/25). Conclusion. Results indicate a eclectic feeding behavior in Lu. evansi, implying potential reservoir hosts for Leishmania spp. and increasing transmission risk. This study is a first step towards understanding the diversity of mammalian blood sources used by sandflies, that may be crucial for vector identification and formulation of effective control measures.

Introducción. En 2018, en la vereda El Alférez de Los Montes de María (Bolívar, Colombia), un macrofoco de leishmaniasis, se reportó el primer caso y se evidenciaron cambios en la distribución y ecoepidemiología de la enfermedad. No obstante, las interacciones entre vectores y fauna local aún son desconocidas. Objetivo. Evaluar la diversidad de flebotomíneos y sus fuentes de alimentación sanguínea en la comunidad de El Alférez del municipio de El Carmen de Bolívar (Bolívar, Colombia). Materiales y métodos. En el 2018, se recolectaron flebotomíneos mediante trampas de luz led ubicadas en el domicilio, el peridomicilio y en el área silvestre, y se identificaron a nivel de especie. Se utilizó la reacción en cadena de la polimerasa múltiple dirigida al gen mitocondrial citocromo B para analizar la sangre del aparato digestivo. Resultados. Lutzomyia evansi fue la especie más abundante (71,85 %; n = 485/675), seguida por Lu. panamensis, Lu. gomezi, Lu. trinidadensis, Lu. dubitans, Lu. abonnenci y Lu. aclydifera. El 25 % (n = 25/100) de las especies analizadas tuvieron como fuentes de ingesta sanguínea a Canis familiaris (36 %; n = 9/25), Ovis aries (36 %; n = 9/25), Bos taurus (24 %; n = 6/25), Sus scrofa (20 %; n = 5/25) y Homo sapiens (8 %; n = 2/25). Lutzomyia evansi fue la especie con la mayor frecuencia de alimentación (68 %; n = 17/25), predominantemente de una sola especie (44 %; n = 11/25) o de varias (24 %; n = 6/25).

Feline leishmaniosis in the Mediterranean Basin: a multicenter study.

BACKGROUND: Cats are now recognized as competent hosts for Leishmania infantum and a blood source for sand fly vectors. Although canine leishmaniosis (CanL) is endemic in Mediterranean Basin countries, large-scale epidemiological studies are lacking for feline leishmaniosis (FeL). This study aimed to assess the prevalence of L. infantum infections, associated risk factors, clinical signs, and clinicopathological abnormalities in domestic cat populations from six Mediterranean Basin countries. METHODS: From 2019 to 2022, blood and serum samples of cats (n = 2067) living in Italy (n = 300), Greece (n = 297), Portugal (n = 295), France (n = 231), Israel (n = 313), and Spain (n = 631) were collected along with animal data (i.e., age, sex, breed, housing conditions, and geographical origin), clinical signs, and laboratory blood test parameters. Cats were grouped according to their age as kittens (up to 1 year), young (older than 1 and younger than 7 years), mature (between 7 and 10 years), and senior (older than 10 years). Serum samples were tested for L. infantum by immunofluorescence antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA), and blood samples of seropositive cats were tested for L. infantum kinetoplast deoxyribonucleic acid (kDNA). Viral infection by feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) was molecularly addressed in all cats enrolled. Statistical analysis was performed to evaluate the association between the risk of L. infantum infection and independent variables, and among co-infection of L. infantum with FIV and/or FeLV, clinical signs, and clinicopathological abnormalities. RESULTS: Overall, 17.3% (358/2067) of cats scored positive for L. infantum by serological tests. Specifically, 24.7% were from Portugal, 23.2% from Greece, 16.6% from Israel, 15% from Spain, 13.3% from France, and 12.6% from Italy. Leishmania infantum DNA was detected in 15 seropositive animals. Housing condition and FIV infection proved to be risk factors for FeL. Leishmania seropositivity was significantly associated with weight loss, lymphadenomegaly, gingivostomatitis, and oral ulcers, as well as with reduced albumin and albumin/globulin ratio, increased total globulins and total proteins, leukocytosis, and thrombocytosis. CONCLUSIONS: This study provides, for the first time, a large-scale epidemiological survey on FeL and its clinical presentation, revealing that L. infantum circulates among domestic cats, especially shelter/free-roaming and FIV-infected animals, living in CanL endemic countries of the Mediterranean Basin.

Entomological inferences highlight the risk of Leishmania transmission in the urban area of Porto Velho, Rondônia, Brazil.

Entomological investigations were conducted for the first time in urban forest remnants of Porto Velho, state of Rondônia, Brazil, to explore the transmission dynamics of Leishmania. Sand fly collections were carried out at ten sites, encompassing both canopy and ground strata, from October to December 2021. A total of 1,671 sand flies were collected, representing 42 species within 12 genera. Nyssomyia Antunesi (n = 384) and Psychodopygus davisi (n = 111) were the most abundant species. Molecular analyses targeting the V7V8 region (18S gene) unveiled the presence of sequences 100% identical to Leishmania infantum in females of Bichromomyia flaviscutellata (1), Nyssomyia Antunesi complex (6), Nyssomyia umbratilis (1), Nyssomyia sp. (1), Psychodopygus ayrozai (1), Ps. davisi (3), Psychodopygus paraensis (1), and Sciopemyia sordellii (1). Sequences 100% similar to Trypanosoma minasense were found in two samples of the Nyssomyia Antunesi complex, and two samples of Sc. sordellii presented 100% identity to a Trypanosoma sp. strain, previously identified in this same sand fly in Rondônia. Sequencing of Cytb fragment suggested Homo sapiens, Dasypus novemcinctus and Tamandua tetradactyla as the blood source for distinct sand flies. The identification of sequences similar to L. infantum in sand flies collected in urban forest fragments is noteworthy, correlating with the recent local and regional occurrence of autochthonous cases of human visceral leishmaniasis. However, further studies are imperative to ascertain the presence of hosts/reservoirs and evaluate the risk of L. infantum transmission to humans.

A breath of fresh air: impact of insect-borne protozoan parasites on the respiratory system.

The protozoan parasites Plasmodium, Leishmania, and Trypanosoma are transmitted by hematophagous insects and cause severe diseases in humans. These infections pose a global threat, particularly in low-resource settings, and are increasingly extending beyond the current endemic regions. Tropism of parasites is crucial for their development, and recent studies have revealed colonization of noncanonical tissues, aiding their survival and immune evasion. Despite receiving limited attention, cumulative evidence discloses the respiratory system as a significant interface for host-pathogen interactions, influencing the course of (co)infection and disease onset. Due to its pathophysiological and clinical implications, we emphasize that further research is needed to better understand the involvement of the respiratory system and its potential to improve prevention, diagnosis, treatment, and interruption of the chain of transmission.

Targeting Leishmania Promastigotes and Amastigotes Forms through Amino Acids and Peptides: A Promising Therapeutic Strategy.

Millions of people worldwide are affected by leishmaniasis, caused by the Leishmania parasite. Effective treatment is challenging due to the biological complexity of the parasite, drug toxicity, and increasing resistance to conventional drugs. To combat this disease, the development of specific strategies to target and selectively eliminate the parasite is crucial. This Review highlights the importance of amino acids in the developmental stages of Leishmania as a factor determining whether the infection progresses or is suppressed. It also explores the use of peptides as alternatives in parasite control and the development of novel targeted treatments. While these strategies show promise for more effective and targeted treatment, further studies to address the remaining challenges are imperative.

The repertoire of iron superoxide dismutases from Leishmania infantum as targets in the search for therapeutic agents against leishmaniasis.

Species of Leishmania and Trypanosoma genera are the causative agents of relevant parasitic diseases. Survival inside their hosts requires the existence of a potent antioxidant enzymatic machinery. Four iron superoxide dismutases have been described in trypanosomatids (FeSODA, FeSODB1, FeSODB2, and FeSODC) that hold a potential as therapeutic targets. Nonetheless, very few studies have been developed that make use of the purified enzymes. Moreover, FeSODC remains uncharacterised in Leishmania. In this work, for the first time, we describe the purification and enzymatic activity of recombinant versions of the four Leishmania FeSOD isoforms and establish an improved strategy for developing inhibitors. We propose a novel parameter [(V*cyt. c - Vcyt. c)/Vcyt. c] which, in contrast to that used in the classical cytochrome c reduction assay, correlates linearly with enzyme concentration. As a proof of concept, we determine the IC50 values of two ruthenium carbosilane metallodendrimers against these isoforms.

Prevalence of Leishmania infection in 205 cats from a referral hospital population in Brazil (2021-2022).

Leishmaniases are a group of neglected diseases of significant public health concern, with Brazil being the primary focus of this disease in the Americas. The municipality of Sobral, in the state of Ceará, is a historical focus of visceral leishmaniasis in both humans and dogs, but data on Leishmania spp. infections in cats are limited. Between April 2021 and February 2022, 205 cats from a referral hospital population were sampled and tested for Leishmania spp. by real-time PCR. Eight cats (3.9%; 95% CI: 1.7-7.5%) tested positive. Among these, three (37.5%) displayed clinical signs compatible with feline leishmaniosis. Non-domiciled cats showed significantly higher positivity compared to domiciled ones (Fisher's exact test, P = 0.0124). Considering their potential role as reservoirs of L. infantum, it is crucial to conduct further studies to understand the Leishmania spp. circulating among cats in Sobral and to implement measures for reducing their exposure to phlebotomine sand fly vectors in this important focus of leishmaniases.

Leishmania spp. in equids and their potential vectors in endemic areas of canine leishmaniasis.

Equids may be infected by zoonotic Leishmania spp., including Leishmania infantum, in regions where canine leishmaniasis (CanL) is endemic, and Leishmania martiniquensis, which has been reported in horses from Central Europe. This study was designed to evaluate the occurrence of both Leishmania spp. among equids living in CanL endemic areas of Italy, as well as to identify dipteran vectors from the same habitats. From March to October 2023, blood, serum and tissue samples from skin lesions were collected from equids (n = 98; n = 56 donkeys and n = 42 horses) living in Italy, as well as sand flies and biting midges. Blood samples (n = 98) and skin lesions (n = 56) were tested for Leishmania spp. by conventional and real time PCRs and sera were tested by immunofluorescence antibody tests (IFAT) for both L. infantum and L. martiniquensis. Insects were morphologically identified, and female specimens (n = 268 sand flies, n = 7 biting midges) analyzed for Leishmania DNA, as well as engorged sand flies (n = 16) for blood-meal detection. Two animals with skin lesions (i.e., one donkey and one horse) scored positive for Leishmania spp. DNA, and 19 animals (i.e., 19.4%; n = 13 donkeys and n = 6 horses) were seropositive for L. infantum, with five of them also for L. martiniquensis. Most seropositive animals had no dermatological lesions (i.e., 68.4%) while both animals molecularly positive for Leishmania spp. scored seronegative. Of the 356 sand flies collected, 12 females (i.e., n = 8 Sergentomyia minuta; n = 3 Phlebotomus perniciosus, n = 1 Phlebotomus perfiliewi) were positive for Leishmania spp. DNA, and one out of seven biting midges collected was DNA-positive for L. infantum. Moreover, engorged sand flies scored positive for human and equine DNA. Data suggest that equids living in CanL endemic areas are exposed to Leishmania spp., but their role in the circulation of the parasite needs further investigations.

Leishmaniases in Ethiopia: a scoping review protocol to determine the scope of research and remaining gaps.

INTRODUCTION: The leishmaniases are among the group of neglected tropical diseases that cause significant morbidity and mortality each year. Currently, the East Africa region has the highest visceral leishmaniasis burden in the world. Ethiopia is one of the East African countries that reports both visceral and cutaneous forms of the disease. As part of the Nairobi Declaration, Ethiopia showed commitment to the elimination of visceral leishmaniasis by 2030. In this endeavour, it is important to understand the scope of research conducted on leishmaniases in the country and identify where the research gaps exist. Determining the research landscape is vital in the plan towards leishmaniases control and elimination. It will help to reference conducted research, determine if systematic reviews are warranted and help prioritise future research directions. METHODS AND ANALYSIS: This protocol was developed with reference to the JBI Scoping Review Methodology Group's guidance on conducting scoping reviews and the PRISMA-ScR reporting guidelines for scoping reviews. The following databases will be searched: PubMed, Embase via Embase.com, Web of Science Core Collection, Cochrane CENTRAL, Global Index Medicus, ClinicalTrials.gov, the Pan African Clinical Trials Registry and PROSPERO. Locally published literature that may not be indexed in the above-mentioned systems will be identified through team members familiar with the setting. Each record will be dually and blindly reviewed in an abstract-title screen and full-text screen using inclusion-exclusion criteria. Included articles must contain an in-depth discussion of leishmaniasis in Ethiopia. Data extracted will consist of study themes, study types, and categories and subcategories each defined in the developed codebook, in addition to type of leishmania, year of publication, funding source and the number of citations. Results will be reported with summary statistics. ETHICS AND DISSEMINATION: Individual consenting and ethical approvals are not applicable. We plan to disseminate our findings to the appropriate stakeholders.

Prevalence and transmission of the most relevant zoonotic and vector-borne pathogens in the Yucatan peninsula: A review.

BACKGROUND: Habitat modification and land use changes impact ecological interactions and alter the relationships between humans and nature. Mexico has experienced significant landscape modifications at the local and regional scales, with negative effects on forest cover and biological biodiversity, especially in the Yucatan peninsula in southeastern Mexico. Given the close relationship between landscape modification and the transmission of zoonotic and vector-borne diseases, it is essential to develop criteria for identifying priority zoonoses in the south of the country. METHODOLOGY/PRINCIPAL FINDINGS: We reviewed 165 published studies on zoonotic and vector-borne diseases in the region (2015-2024). We identified the most frequent vectors, reservoirs, and hosts, the most prevalent infections, and the factors associated with transmission risk and the anthropogenic landscape modification in urban, rural, ecotone, and sylvatic habitats. The most relevant pathogens of zoonotic risk included Trypanosoma cruzi, arboviruses, Leishmania, Rickettsia, Leptospira, and Toxoplasma gondii. Trypanosoma cruzi was the vector-borne agent with the largest number of infected vertebrate species across habitats, while Leishmania and arboviruses were the ones that affected the greatest number of people. Dogs, cats, backyard animals, and their hematophagous ectoparasites are the most likely species maintaining the transmission cycles in human settlements, while rodents, opossums, bats, and other synanthropic animals facilitate connection and transmission cycles between forested habitats with human-modified landscapes. Pathogens displayed different prevalences between the landscapes, T. cruzi, arbovirus, and Leptospira infections were the most prevalent in urban and rural settlements, whereas Leishmania and Rickettsia had similar prevalence across habitats, likely due to the diversity and abundance of the infected vectors involved. The prevalence of T. gondii and Leptospira spp. may reflect poor hygiene conditions. Additionally, results suggest that prevalence of zoonotic and vector-borne diseases is higher in deforested areas and agricultural aggregates, and in sites with precarious health and infrastructure services. CONCLUSIONS: Some hosts, vectors, and transmission trends of zoonotic and vector-borne diseases in the YP are well known but others remain poorly recognized. It is imperative to reinforce practices aimed at increasing the knowledge, monitoring, prevention, and control of these diseases at the regional level. We also emphasize the need to perform studies on a larger spatio-temporal scale under the socio-ecosystem perspective, to better elucidate the interactions between pathogens, hosts, vectors, environment, and sociocultural and economic aspects in this and many other tropical regions.

Rapid and reliable detection of Leishmania antibodies in canine serum with double-antigen sandwich homogeneous chemical luminescence.

BACKGROUND: Leishmaniasis, caused by Leishmania spp. parasites, is an important zoonotic disease globally, posing severe threats to humans and animals. In the absence of effective vaccines, reliable serological diagnostic methods are critical for disease control. However, the enzyme-linked immunosorbent assay (ELISA) and immunochromatographic assay have limitations due to complexity, time required and/or sensitivity. Therefore, our objective was to develop an accurate, rapid and user-friendly detection method of canine leishmania antibody based on double-antigen sandwich homogeneous chemical luminescence. METHODS: Homogeneous chemiluminescent technology was employed, and expressed recombinant fusion proteins containing full-length K9, K39 and K26 repeat sequences were used as diagnostic antigens. To establish a dual-antigen sandwich serological assay capable of detecting various antibody types, a factorial design was used to optimize concentrations of diagnostic antigen-receptor microspheres and of biotinylated diagnostic antigens, as well as of reaction solution composition and reaction duration. To evaluate and validate this newly developed method, we collected 41 Leishmania-positive serum samples, 30 Leishmania-negative control serum samples and 78 clinical serum samples for which no diagnostic information was available. Comparative analyses were performed using parasitological testing and an indirect ELISA as reference methods, focusing on diagnostic sensitivity and specificity. RESULTS: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis confirmed the purification of the diagnostic antigens, which exhibited clear bands without impurities. Based on results from the 41 Leishmania-positive samples and 30 Leishmania-negative samples, there was sufficient sensitivity to detect samples diluted up to 256-fold, with analytical specificity of 100%. Overall diagnostic sensitivity was 100% and diagnostic specificity was 93.3%. Diagnostic performance was highly consistent between the newly developed method and the indirect ELISA (Kappa = 0.82, P < 0.01). Testing could be completed within 35 min with the new method CONCLUSIONS: We have developed a novel double-antigen sandwich homogeneous chemical luminescence method to detect canine Leishmania antibodies, with high sensitively and specificity, a short incubation interval and a simple protocol. This streamlined approach not only offers a sensitive and efficient method for clinical diagnosis but also has great potential for use in automated testing.

hsp70 PCR-RFLP as an alternative tool to identify Sauroleishmania species.

Sauroleishmania spp. comprises one of the four Leishmania subgenera, which has been historically considered a non-pathogenic protozoan of reptiles. However, some strains appear to be transiently infective to mammals, and recent findings have detected these parasites in dogs and humans in areas where leishmaniasis is endemic. Herein, the digestion pattern of PCR-RFLP of the 234 bp-hsp70 fragment was evaluated as a simpler and cheaper tool to distinguish the Sauroleishmania species from the other Leishmania subgenera. As a result, the digestion of the 234 bp-hsp70 fragments with HaeIII produced a banding pattern specific to the four Sauroleishmania strains assessed. This technique could contribute to the identification of Leishmania parasites isolated from sandflies, reptiles, or even mammals in fieldworks as an alternative to the use of laborious and expensive methodologies.

Feline immunodeficiency virus, feline leukemia virus and Leishmania spp. prevalence in cats from shelters in Mato Grosso do Sul, Brazil.

Diseases such as those caused by feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) represent health problems for cats. Feline leishmaniasis (FL) has been reported in several cities across the country. The objective was to carry out a clinical-epidemiological and laboratory study of FIV, FeLV and FL in cats from shelters in Dourados, Mato Grosso do Sul, Brazil. Blood samples and swabs from the conjunctival and nasal mucosa were obtained from 75 cats, from four animal shelters. Serology for FIV and FeLV was performed. For Leishmania, polymerase chain reaction (PCR) was performed on blood, conjunctiva and nasal mucosa. In the immunochromatographic serological test, seven cats tested positive for FIV and none for FeLV. No samples was positive in PCR for Leishmania. The study showed that despite the presence of human and canine leishmaniasis in the studied region, Leishmania spp. were absent in the cats studied. To avoid an increase in contagion in shelters, it is essential isolate cats with FIV.