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Ricardo Molina - One of the best experts on this subject based on the ideXlab platform.

  • opportunistic feeding behaviour and leishmania infantum detection in Phlebotomus Perniciosus females collected in the human leishmaniasis focus of madrid spain 2012 2018
    PLOS Neglected Tropical Diseases, 2021
    Co-Authors: Estela Gonzalez, Ricardo Molina, Sonia Ruiz, Andrés Iriso, Irene Aldea, Ana Tello, Daniel Fernandez, Maribel Jiménez
    Abstract:

    Background An outbreak of human leishmaniasis due to Leishmania infantum has been registered in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys carried out in the municipalities of Fuenlabrada, Leganes, Getafe and Humanes de Madrid showed that Phlebotomus Perniciosus is the only potential vector. In this work, an intensive molecular surveillance was performed in P. Perniciosus females captured in the region between 2012 and 2018. Methodology/Principal findings A total of 1805 P. Perniciosus females were analyzed for Leishmania infection, and 1189 of them also for bloodmeal identification. Eleven different species of vertebrate were detected by amplification and subsequent sequencing of the 359 bp cytb fragment. The most prevalent blood source identified was hare (n = 553, 46.51%), followed by rabbit (n = 262, 21.95%). Less frequent were cat (n = 45, 3.80%), human (n = 34, 2.90%), pig (n = 14, 1.20%), horse (n = 11, 0.93%), sheep (n = 3, 0.25%), rhea (n = 3, 0.25%), partridge (n = 1, 0.09%) and chicken (n = 1, 0.09%). The distribution of the blood meal sources varied between the different locations. Regarding L. infantum detection, PCR amplification of a fragment of kDNA, cpb gene and ITS1 region showed 162 positive specimens (8.97%). The highest infection rate was found in the municipality of Leganes (15.17%). Conclusions The results of this molecular survey in P. Perniciosus, the only leishmaniasis vector in the outbreak occurred in southwestern Madrid region, showed its opportunistic blood-feeding behaviour, high infection rates and the differences between the different points. This study was an essential part of the intensive surveillance plan in the area and the results obtained have supported the implementation of control measures in the outbreak.

  • Opportunistic feeding behaviour and Leishmania infantum detection in Phlebotomus Perniciosus females collected in the human leishmaniasis focus of Madrid, Spain (2012-2018).
    'Public Library of Science (PLoS)', 2021
    Co-Authors: Estela Gonzalez, Ricardo Molina, Sonia Ruiz, Andrés Iriso, Irene Aldea, Ana Tello, Daniel Fernandez, Maribel Jiménez
    Abstract:

    BackgroundAn outbreak of human leishmaniasis due to Leishmania infantum has been registered in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys carried out in the municipalities of Fuenlabrada, Leganés, Getafe and Humanes de Madrid showed that Phlebotomus Perniciosus is the only potential vector. In this work, an intensive molecular surveillance was performed in P. Perniciosus females captured in the region between 2012 and 2018.Methodology/principal findingsA total of 1805 P. Perniciosus females were analyzed for Leishmania infection, and 1189 of them also for bloodmeal identification. Eleven different species of vertebrate were detected by amplification and subsequent sequencing of the 359 bp cytb fragment. The most prevalent blood source identified was hare (n = 553, 46.51%), followed by rabbit (n = 262, 21.95%). Less frequent were cat (n = 45, 3.80%), human (n = 34, 2.90%), pig (n = 14, 1.20%), horse (n = 11, 0.93%), sheep (n = 3, 0.25%), rhea (n = 3, 0.25%), partridge (n = 1, 0.09%) and chicken (n = 1, 0.09%). The distribution of the blood meal sources varied between the different locations. Regarding L. infantum detection, PCR amplification of a fragment of kDNA, cpb gene and ITS1 region showed 162 positive specimens (8.97%). The highest infection rate was found in the municipality of Leganés (15.17%).ConclusionsThe results of this molecular survey in P. Perniciosus, the only leishmaniasis vector in the outbreak occurred in southwestern Madrid region, showed its opportunistic blood-feeding behaviour, high infection rates and the differences between the different points. This study was an essential part of the intensive surveillance plan in the area and the results obtained have supported the implementation of control measures in the outbreak

  • rabbit trypanosome detection in Phlebotomus Perniciosus sand flies from the leishmaniasis outbreak in madrid spain
    Acta Tropica, 2018
    Co-Authors: Estela Gonzalez, Ricardo Molina, Maribel Jiménez
    Abstract:

    Phlebotomine sand flies are known vectors of several pathogens. In Spain, Phlebotomus Perniciosus and Phlebotomus ariasi are the proven vectors of Leishmania infantum. Since 2010 a human leishmaniasis outbreak has been notified in Madrid region, central Spain. Studies have shown that P. Perniciosus is the only vector confirmed in the focus area and that rabbits and hares are the wild reservoirs incriminated in the cycle of the parasite in the outbreak. Trypanosoma nabiasi is a trypanosomatid found in wild rabbits and its presence has been reported in wild rabbits from southern Spain. Moreover, co-infection with L. infantum was found in some of these animals. However, in Madrid region, there is no information about the transmission of this trypanosome in rabbits. Hence, in this study we investigate if T. nabiasi could be circulating in the aforementioned leishmaniasis focus. Wild P. Perniciosus female sand flies were captured in the affected area and analyzed using molecular methods. T. nabiasi DNA was detected in 20 out of 155 female sand flies fed on rabbits by amplification and subsequent sequencing of ITS1 and SSU rRNA fragments. Therefore, we describe for the first time the presence of T. nabiasi and its co-infection with L. infantum in P. Perniciosus female sand flies. More investigation is needed in order to elucidate the role of P. Perniciosus in the transmission of T. nabiasi among rabbits and its potential consequences.

  • detection of high leishmania infantum loads in Phlebotomus Perniciosus captured in the leishmaniasis focus of southwestern madrid region spain by real time pcr
    Acta Tropica, 2017
    Co-Authors: Estela Gonzalez, Ricardo Molina, Ana Ayuso Alvarez, Sonia Ruiz, Maribel Jiménez
    Abstract:

    Since 2010 a human leishmaniasis outbreak has been notified in southwestern Madrid region that still remains active. Entomological surveys have been carried out in the affected area in order to obtain information about species diversity, distribution, and density of sand flies. Moreover, molecular identification of blood meal preferences of sand flies and molecular detection of Leishmania infantum has been performed. In this work, we optimized a real time PCR assay in order to determine parasite loads in unfed and blood-fed Phlebotomus Perniciosus female sand flies caught in the focus area. Results showed elevated parasite loads in nearly 70% of the studied positive sand flies. Furthermore, significantly higher parasite loads were observed in females without blood in their guts. In conclusion, high L. infantum loads found in P. Perniciosus sand flies from the Madrid focus support the exceptional characteristics of this outbreak.

  • Natural transmission of Leishmania infantum through experimentally infected Phlebotomus Perniciosus highlights the virulence of Leishmania parasites circulating in the human visceral leishmaniasis outbreak in Madrid, Spain
    Veterinary Research, 2015
    Co-Authors: Ines Martin-martin, Maribel Jiménez, Estela Gonzalez, César Eguiluz, Ricardo Molina
    Abstract:

    Abstract A human leishmaniasis outbreak is occurring in the Madrid region, Spain, with the parasite and vector involved being Leishmania infantum and Phlebotomus Perniciosus respectively. The aim of this study was to investigate the virulence of L. infantum isolates from the focus using a natural transmission model. Hamsters were infected by intraperitoneal inoculation (IP) or by bites of sand flies experimentally infected with L. infantum isolates obtained from P. Perniciosus collected in the outbreak area (IPER/ES/2012/BOS1FL1 and IPER/ES/2012/POL2FL6) and a well characterized L. infantum strain JPCM5 (MCAN/ES/98/LLM-877). Hamster infections were monitored by clinical examination, serology, culture, parasite burden, Giemsa-stained imprints, PCR, histopathology and xenodiagnostic studies. Establishment of infection of L. infantum was achieved with the JPCM5 strain and outbreak isolates by both P. Perniciosus infective bites or IP route. However, high virulence of BOS1FL1 and POL2FL6 isolates was highlighted by the clinical outcome of disease, high parasite detection in spleen and liver, high parasitic loads and positivity of Leishmania serology. Transmission by bite of POL2FL6 infected flies generated a slower progression of clinical disease than IP infection, but both groups were infective to P. Perniciosus by xenodiagnosis at 2 months post-infection. Conversely, hamsters inoculated with JPCM5 were not infective to sand flies. Histopathology studies confirmed the wide spread of POL2FL6 parasites to several organs. A visceral leishmaniasis model that mimics the natural transmission in nature allowed us to highlight the high virulence of isolates that are circulating in the focus. These findings contribute to a better understanding of the outbreak epidemiology.

Maribel Jiménez - One of the best experts on this subject based on the ideXlab platform.

  • opportunistic feeding behaviour and leishmania infantum detection in Phlebotomus Perniciosus females collected in the human leishmaniasis focus of madrid spain 2012 2018
    PLOS Neglected Tropical Diseases, 2021
    Co-Authors: Estela Gonzalez, Ricardo Molina, Sonia Ruiz, Andrés Iriso, Irene Aldea, Ana Tello, Daniel Fernandez, Maribel Jiménez
    Abstract:

    Background An outbreak of human leishmaniasis due to Leishmania infantum has been registered in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys carried out in the municipalities of Fuenlabrada, Leganes, Getafe and Humanes de Madrid showed that Phlebotomus Perniciosus is the only potential vector. In this work, an intensive molecular surveillance was performed in P. Perniciosus females captured in the region between 2012 and 2018. Methodology/Principal findings A total of 1805 P. Perniciosus females were analyzed for Leishmania infection, and 1189 of them also for bloodmeal identification. Eleven different species of vertebrate were detected by amplification and subsequent sequencing of the 359 bp cytb fragment. The most prevalent blood source identified was hare (n = 553, 46.51%), followed by rabbit (n = 262, 21.95%). Less frequent were cat (n = 45, 3.80%), human (n = 34, 2.90%), pig (n = 14, 1.20%), horse (n = 11, 0.93%), sheep (n = 3, 0.25%), rhea (n = 3, 0.25%), partridge (n = 1, 0.09%) and chicken (n = 1, 0.09%). The distribution of the blood meal sources varied between the different locations. Regarding L. infantum detection, PCR amplification of a fragment of kDNA, cpb gene and ITS1 region showed 162 positive specimens (8.97%). The highest infection rate was found in the municipality of Leganes (15.17%). Conclusions The results of this molecular survey in P. Perniciosus, the only leishmaniasis vector in the outbreak occurred in southwestern Madrid region, showed its opportunistic blood-feeding behaviour, high infection rates and the differences between the different points. This study was an essential part of the intensive surveillance plan in the area and the results obtained have supported the implementation of control measures in the outbreak.

  • Opportunistic feeding behaviour and Leishmania infantum detection in Phlebotomus Perniciosus females collected in the human leishmaniasis focus of Madrid, Spain (2012-2018).
    'Public Library of Science (PLoS)', 2021
    Co-Authors: Estela Gonzalez, Ricardo Molina, Sonia Ruiz, Andrés Iriso, Irene Aldea, Ana Tello, Daniel Fernandez, Maribel Jiménez
    Abstract:

    BackgroundAn outbreak of human leishmaniasis due to Leishmania infantum has been registered in an urban area of southwestern Madrid, Spain, since 2010. Entomological surveys carried out in the municipalities of Fuenlabrada, Leganés, Getafe and Humanes de Madrid showed that Phlebotomus Perniciosus is the only potential vector. In this work, an intensive molecular surveillance was performed in P. Perniciosus females captured in the region between 2012 and 2018.Methodology/principal findingsA total of 1805 P. Perniciosus females were analyzed for Leishmania infection, and 1189 of them also for bloodmeal identification. Eleven different species of vertebrate were detected by amplification and subsequent sequencing of the 359 bp cytb fragment. The most prevalent blood source identified was hare (n = 553, 46.51%), followed by rabbit (n = 262, 21.95%). Less frequent were cat (n = 45, 3.80%), human (n = 34, 2.90%), pig (n = 14, 1.20%), horse (n = 11, 0.93%), sheep (n = 3, 0.25%), rhea (n = 3, 0.25%), partridge (n = 1, 0.09%) and chicken (n = 1, 0.09%). The distribution of the blood meal sources varied between the different locations. Regarding L. infantum detection, PCR amplification of a fragment of kDNA, cpb gene and ITS1 region showed 162 positive specimens (8.97%). The highest infection rate was found in the municipality of Leganés (15.17%).ConclusionsThe results of this molecular survey in P. Perniciosus, the only leishmaniasis vector in the outbreak occurred in southwestern Madrid region, showed its opportunistic blood-feeding behaviour, high infection rates and the differences between the different points. This study was an essential part of the intensive surveillance plan in the area and the results obtained have supported the implementation of control measures in the outbreak

  • rabbit trypanosome detection in Phlebotomus Perniciosus sand flies from the leishmaniasis outbreak in madrid spain
    Acta Tropica, 2018
    Co-Authors: Estela Gonzalez, Ricardo Molina, Maribel Jiménez
    Abstract:

    Phlebotomine sand flies are known vectors of several pathogens. In Spain, Phlebotomus Perniciosus and Phlebotomus ariasi are the proven vectors of Leishmania infantum. Since 2010 a human leishmaniasis outbreak has been notified in Madrid region, central Spain. Studies have shown that P. Perniciosus is the only vector confirmed in the focus area and that rabbits and hares are the wild reservoirs incriminated in the cycle of the parasite in the outbreak. Trypanosoma nabiasi is a trypanosomatid found in wild rabbits and its presence has been reported in wild rabbits from southern Spain. Moreover, co-infection with L. infantum was found in some of these animals. However, in Madrid region, there is no information about the transmission of this trypanosome in rabbits. Hence, in this study we investigate if T. nabiasi could be circulating in the aforementioned leishmaniasis focus. Wild P. Perniciosus female sand flies were captured in the affected area and analyzed using molecular methods. T. nabiasi DNA was detected in 20 out of 155 female sand flies fed on rabbits by amplification and subsequent sequencing of ITS1 and SSU rRNA fragments. Therefore, we describe for the first time the presence of T. nabiasi and its co-infection with L. infantum in P. Perniciosus female sand flies. More investigation is needed in order to elucidate the role of P. Perniciosus in the transmission of T. nabiasi among rabbits and its potential consequences.

  • detection of high leishmania infantum loads in Phlebotomus Perniciosus captured in the leishmaniasis focus of southwestern madrid region spain by real time pcr
    Acta Tropica, 2017
    Co-Authors: Estela Gonzalez, Ricardo Molina, Ana Ayuso Alvarez, Sonia Ruiz, Maribel Jiménez
    Abstract:

    Since 2010 a human leishmaniasis outbreak has been notified in southwestern Madrid region that still remains active. Entomological surveys have been carried out in the affected area in order to obtain information about species diversity, distribution, and density of sand flies. Moreover, molecular identification of blood meal preferences of sand flies and molecular detection of Leishmania infantum has been performed. In this work, we optimized a real time PCR assay in order to determine parasite loads in unfed and blood-fed Phlebotomus Perniciosus female sand flies caught in the focus area. Results showed elevated parasite loads in nearly 70% of the studied positive sand flies. Furthermore, significantly higher parasite loads were observed in females without blood in their guts. In conclusion, high L. infantum loads found in P. Perniciosus sand flies from the Madrid focus support the exceptional characteristics of this outbreak.

  • Natural transmission of Leishmania infantum through experimentally infected Phlebotomus Perniciosus highlights the virulence of Leishmania parasites circulating in the human visceral leishmaniasis outbreak in Madrid, Spain
    Veterinary Research, 2015
    Co-Authors: Ines Martin-martin, Maribel Jiménez, Estela Gonzalez, César Eguiluz, Ricardo Molina
    Abstract:

    Abstract A human leishmaniasis outbreak is occurring in the Madrid region, Spain, with the parasite and vector involved being Leishmania infantum and Phlebotomus Perniciosus respectively. The aim of this study was to investigate the virulence of L. infantum isolates from the focus using a natural transmission model. Hamsters were infected by intraperitoneal inoculation (IP) or by bites of sand flies experimentally infected with L. infantum isolates obtained from P. Perniciosus collected in the outbreak area (IPER/ES/2012/BOS1FL1 and IPER/ES/2012/POL2FL6) and a well characterized L. infantum strain JPCM5 (MCAN/ES/98/LLM-877). Hamster infections were monitored by clinical examination, serology, culture, parasite burden, Giemsa-stained imprints, PCR, histopathology and xenodiagnostic studies. Establishment of infection of L. infantum was achieved with the JPCM5 strain and outbreak isolates by both P. Perniciosus infective bites or IP route. However, high virulence of BOS1FL1 and POL2FL6 isolates was highlighted by the clinical outcome of disease, high parasite detection in spleen and liver, high parasitic loads and positivity of Leishmania serology. Transmission by bite of POL2FL6 infected flies generated a slower progression of clinical disease than IP infection, but both groups were infective to P. Perniciosus by xenodiagnosis at 2 months post-infection. Conversely, hamsters inoculated with JPCM5 were not infective to sand flies. Histopathology studies confirmed the wide spread of POL2FL6 parasites to several organs. A visceral leishmaniasis model that mimics the natural transmission in nature allowed us to highlight the high virulence of isolates that are circulating in the focus. These findings contribute to a better understanding of the outbreak epidemiology.

Petr Volf - One of the best experts on this subject based on the ideXlab platform.

  • Phlebotomus Perniciosus recombinant salivary proteins polarize murine macrophages toward the anti inflammatory phenotype
    Frontiers in Cellular and Infection Microbiology, 2020
    Co-Authors: Petra Sumova, Petr Volf, Tereza Lestinova, Nikola Polanska, Tatiana Spitzova, Barbora Kalouskova, Ondrej Vanek, Iva Rohousova
    Abstract:

    Phlebotomus Perniciosus (Diptera: Phlebotominae) is a medically and veterinary important insect vector. It transmits the unicellular parasite Leishmania infantum that multiplies intracellularly in macrophages causing life-threatening visceral diseases. Leishmania establishment in the vertebrate host is substantially influenced by immunomodulatory properties of vector saliva that are obligatorily co-injected into the feeding site. The repertoire of P. Perniciosus salivary molecules has already been revealed and, subsequently, several salivary proteins have been expressed. However, their immunogenic properties have never been studied. In our study, we tested three P. Perniciosus recombinant salivary proteins – an apyrase rSP01 and yellow-related proteins rSP03 and rSP03B – and showed their anti-inflammatory nature on the murine bone-marrow derived macrophages. Even in the presence of pro-inflammatory stimuli (IFN-and bacterial lipopolysaccharide, LPS, all three recombinant proteins inhibited nitric oxide production. Moreover, rSP03 seems to have a very strong anti-inflammatory effect since it enhanced arginase activity, increased the production of IL-10, and inhibited the production of TNF- even in macrophages stimulated with IFN- and LPS. These results suggest that P. Perniciosus apyrase and yellow-related proteins may serve as enhancing factors in sand fly saliva, facilitating the development of Leishmania infection along with their anti-haemostatic properties. Additionally, rSP03 and rSP03B did not elicit the delayed-type-hypersensitivity response in mice pre-exposed to P. Perniciosus bites (measured as visible skin reaction). The results of our study may help to understand the potential function of recombinant´s native counterparts and their role in Leishmania transmission and establishment within the host.

  • monitoring leishmania infection and exposure to Phlebotomus Perniciosus using minimal and non invasive canine samples
    Parasites & Vectors, 2020
    Co-Authors: Carla Maia, Petr Volf, Petra Sumova, Tatiana Kostalova, Tereza Lestinova, Jose Manuel Cristovao, Andre Pereira, Lenea Campino
    Abstract:

    In endemic areas of zoonotic leishmaniosis caused by L. infantum, early detection of Leishmania infection in dogs is essential to control the dissemination of the parasite to humans. The aim of this study was to evaluate the serological and/or molecular diagnostic performance of minimally and non-invasive samples (conjunctiva cells (CS) and peripheral blood (PB)) for monitoring Leishmania infection/exposure to Phlebotomus Perniciosus salivary antigens in dogs at the beginning and the end of sand fly seasonal activity (May and October, respectively) and to assess associated risks factors. A total of 208 sheltered dogs from endemic areas of leishmaniosis were screened. Leishmania DNA detection in PB on filter paper and CS was performed by nested-PCR (nPCR), while the detection of anti-Leishmania antibodies was performed using IFAT and ELISA. The exposure to P. Perniciosus salivary antigens (SGH, rSP01 and rSP03B + rSP01) was measured by ELISA. Ninety-seven (46.6%) and 116 (55.8%) of the 208 dogs were positive to Leishmania antibodies or DNA by at least one test at the beginning and end of the sand fly season, respectively. IFAT and ELISA presented a substantial agreement in the serodiagnosis of leishmaniosis. Discrepant PB nPCR results were obtained between sampling points. Leishmania DNA was detected in CS of 72 dogs at the end of the phlebotomine season. The presence of antibodies to the parasite measured by ELISA was significantly higher in dogs presenting clinical signs compatible with leishmaniosis at both sampling points. Phlebotomus Perniciosus salivary antibodies were detected in 179 (86.1%) and 198 (95.2%) of the screened dogs at the beginning and end of the phlebotomine season, respectively. The association between ELISA positivity and clinical signs suggests its usefulness to confirm a clinical suspicion. CS nPCR seems to be an effective and non-invasive method for assessing early exposure to the parasite. PB nPCR should not be used as the sole diagnostic tool to monitor Leishmania infection. The correlation between the levels of antibodies to P. Perniciosus saliva and Leishmania antibodies suggests the use of a humoral response to sand fly salivary antigens as biomarkers of L. infantum infection.

  • impaired development of a miltefosine resistant leishmania infantum strain in the sand fly vectors Phlebotomus Perniciosus and lutzomyia longipalpis
    International Journal for Parasitology-Drugs and Drug Resistance, 2019
    Co-Authors: Lieselotte Van Bockstal, Petr Volf, Jovana Sadlova, Hamide Aslan Suau, Sarah Hendrickx, Claudio Meneses, Shaden Kamhawi, Louis Maes, Guy Caljon
    Abstract:

    Abstract Objectives To gain insight into the propagation of miltefosine (MIL) resistance in visceral leishmaniasis, this laboratory study explored development of resistant parasites with a defective miltefosine transporter (MT) in sand flies. Methods Infectivity, colonization of stomodeal valve and metacyclogenesis of a MIL-resistant (MIL-R) Leishmania infantum LEM3323 line with a defective MT were assessed in the natural sand fly vectors Phlebotomus Perniciosus and Lutzomyia longipalpis. Given our recent description of partial drug dependency of the MT-deficient line, the impact of MIL pre-exposure on sand fly infectivity was explored as well. Results A significant reduction in sand fly infection, stomodeal valve colonization and differentiation into metacyclics (determined by a lower flagellum/cell body length ratio) was observed in both vectors for MIL-R as compared to the isogenic parent MIL-susceptible line. Re-introduction of the wildtype MT gene into MIL-R tended to partially rescue the capacity to infect sand flies. Pre-exposure to MIL did not alter infectivity of the MIL-R line. Conclusion The MIL resistant L. infantum LEM3323 line is significantly hampered in its development and transmissibility potential in two sand fly vector species. Additional studies are warranted to evaluate whether this applies to other visceral Leishmania parasites with acquired MIL-resistance.

  • Experimental infection of Phlebotomus Perniciosus and Phlebotomus tobbi with different Leishmania tropica strains
    International journal for parasitology, 2019
    Co-Authors: Slavica Vaselek, Petr Volf
    Abstract:

    Cutaneous leishmaniasis due to Leishmania tropica is increasingly documented in Europe and the Middle East. Besides its specific vector, Phlebotomus sergenti, permissive Phlebotomus sand flies are suspected as potential vectors of L. tropica. We investigated the susceptibility of two widely distributed species, Phlebotomus Perniciosus and Phlebotomus tobbi. Laboratory-reared sand flies were infected experimentally with L. tropica strains differing in lipophosphoglycan epitopes, geographical distribution and epidemiology. High infection rates, heavy parasite loads and fully developed late-stage infections including colonization of the stomodeal valve were observed in all parasite-vector combinations. Our findings demonstrate that P. Perniciosus and P. tobbi are susceptible to different L. tropica strains and may play a role in their circulation in endemic foci of Europe, the Middle East and North Africa.

  • longitudinal monitoring of anti saliva antibodies as markers of repellent efficacy against Phlebotomus Perniciosus and Phlebotomus papatasi in dogs
    Medical and Veterinary Entomology, 2019
    Co-Authors: J Risueno, Petr Volf, Clara Serna Munoz, L J Bernal, Tatiana Spitzova, Manuel Carlos Lopez, Maria Del Carmen Thomas, Juan Jose Infante, E Berriatua
    Abstract:

    A 2-year longitudinal study of enzyme-linked immunosorbent assay (ELISA) antibodies against Phlebotomus Perniciosus and Phlebotomus papatasi (Diptera: Psychodidae) sandfly saliva was performed in 32 Beagle dogs treated preventively with an imidacloprid-permethrin topical insecticide in an endemic area in Spain. Dogs were grouped into three sandfly exposure groups according to the time of inclusion in the study. Assays analysed immunoglobulin G (IgG) against salivary gland homogenates (SGH) of both species and recombinant P. papatasi rSP32 and P. Perniciosus rSP03B proteins in serum. The dogs were participating in a Leishmania infantum (Kinetoplastida: Trypanosomatidae) vaccine trial and were experimentally infected with the parasite in the second year. No dog acquired natural L. infantum infections during the first year, but most developed anti-saliva antibodies, and median log-transformed optical densities (LODs) were seasonal, mimicking those of local sandflies. This indicates that the repellent efficacy of the insecticide used is below 100%. Multi-level modelling of LODs revealed variability among dogs, autocorrelation and differences according to the salivary antigen and the dog's age. However, dog seroprevalence, estimated using pre-exposure LODs as cut-offs, was relatively low. This, and the fact that dogs did not become naturally infected with L. infantum, would support the efficacy and usefulness of this imidacloprid-permethrin topical insecticide in canine leishmaniasis control.

Luigi Gradoni - One of the best experts on this subject based on the ideXlab platform.

  • examining the relationship of clinical and laboratory parameters with infectiousness to Phlebotomus Perniciosus and its potential infectivity in dogs with overt clinical leishmaniasis
    Frontiers in Veterinary Science, 2021
    Co-Authors: Manuela Gizzarelli, Gioia Bongiorno, Riccardo Bianchi, Valentina Foglia Manzillo, Antonio Bosco, Daniela Giaquinto, Nour El Houda Ben Fayala, Marie Varloud, Alessia Crippa, Luigi Gradoni
    Abstract:

    Infected dogs are considered the main domestic animal reservoirs for Leishmania infantum parasite. Infectiousness to competent phlebotomine vectors has been associated with many factors, the main being the severity of the disease exhibited by infected dogs. This study examines the relationship between different clinical parameters and the infectiousness to colonized Phlebotomus Perniciosus sand flies having a blood meal on dogs. Data obtained in the present study come from an untreated group of Leishmania sick dogs submitted to xenodiagnosis for the evaluation of a spot on insecticide solution. Seventeen dogs were diagnosed as affected by leishmaniasis through clinical examination, immunofluorescence antibody test (IFAT) serology, and loop-mediated isothermal amplification (LAMP). The disease severity (clinical score) was staged by using a numeric value derived from eight clinical and parasitological parameters. Xenodiagnosis was performed on caged dogs exposed for 1.5 h to sand-fly bites. The following parameters related to sand flies were examined: blood feeding (% of blood engorged females), promastigote detection (% of promastigote-positive sand flies), promastigote burden, and the promastigote stage maturation (potential transmissibility rate). Statistical relationship between the clinical score and entomological parameters was investigated, as well as the possible correlation between each clinical and laboratory parameters and sand fly infection/infectivity. The severity of clinical score may influence the blood feeding by, and the probability of promastigote detection in, sand flies; skin lesions seem to be the main factor that influences the rate of blood feeding. Promastigote burden is related to IFAT titer, skin lesions, and clinical score. All entomological parameters are strongly related among them. This study confirms that both P. Perniciosus infection and infectivity are influenced by a dog's clinical condition.

  • laboratory transmission of an asian strain of leishmania tropica by the bite of the southern european sand fly Phlebotomus Perniciosus
    International Journal for Parasitology, 2019
    Co-Authors: Gioia Bongiorno, Trentina Di Muccio, Marina Gramiccia, Riccardo Bianchi, Luigi Gradoni
    Abstract:

    Imported cases of anthroponotic cutaneous leishmaniasis due to Leishmania tropica are increasingly documented in Europe. We investigated the ability of Phlebotomus Perniciosus, a competent vector of Leishmania infantum widespread in southwestern Europe, to support the growth and transmissibility of an Asian strain of L. tropica recently isolated from a refugee. Parasite growth behavior was investigated in laboratory-reared sand flies fed artificially with promastigotes as well as in sand flies infected after biting on footpad lesions induced in hamsters by promastigote inoculation. The evolution of infection was checked by gut microscopy and quantitative real-time PCR, and it was found to be similar between promastigote- and amastigote-initiated infections. In 80% of infected sand flies, despite survival and flourishing growth of promastigotes after blood digestion and defecation, either the parasites died, or failed to migrate to the foregut and/or to mature into infective forms. However, in the remaining 20% L. tropica developed into abundant metacyclic promastigotes. The quantitative real-time PCR assay detected variable loads of gut promastigotes irrespective of morphological evidence of viability or progressive/final death. Parasite transmissibility was investigated by exposing naive hamsters to P. Perniciosus previously infected on chronic lesions induced in hamsters which survived to take a second blood meal. Two months post exposure, lesions developed in skin sites bitten by sand flies confirmed to harbor metacyclic promastigotes; in the following months, the presence of viable and transmissible L. tropica parasites in lesions was demonstrated by xenodiagnosis assays. Our findings support the hypothesis that, in particular epidemiological situations, P. Perniciosus may play the role of an occasional L. tropica vector.

  • The mycobiota of the sand fly Phlebotomus Perniciosus: Involvement of yeast symbionts in uric acid metabolism.
    Environmental microbiology, 2018
    Co-Authors: Elena Martin, Gioia Bongiorno, Luigi Gradoni, Matteo Montagna, L. De Marco, P. Mensah, Ilaria Varotto Boccazzi, Luciano Sacchi, Irene Ricci, Claudio Bandi
    Abstract:

    The knowledge of the fungal mycobiota of arthropods, including the vectors of human and animal diseases, is still limited. Here, the mycobiota associated with the sand fly Phlebotomus Perniciosus, the main vector of leishmaniasis in the western Mediterranean area, by a culture-dependent approach (microbiological analyses and sequencing of the 26S rRNA gene), internal transcribed spacer (ITS) rRNA amplicon-based next-generation sequencing, fluorescence in situ hybridisation (FISH), and genome sequencing of the dominant yeast species was investigated. The dominant species was Meyerozyma guilliermondii, known for its biotechnological applications. The focus was on this yeast and its prevalence in adults, pupae and larvae of reared sand flies (overall prevalence: 57.5%) and of field-collected individuals (overall prevalence: 9%) was investigated. Using whole-mount FISH and microscopic examination, it was further showed that M. guilliermondii colonizes the midgut of females, males and larvae and the distal part of Malpighian tubules of female sand flies, suggesting a possible role in urate degradation. Finally, the sequencing and analysis of the genome of M. guilliermondii allowed predicting the complete uric acid degradation pathway, suggesting that the yeast could contribute to the removal of the excess of nitrogenous wastes after the blood meal of the insect host.

  • Isolation of a Wickerhamomyces anomalus yeast strain from the sandfly Phlebotomus Perniciosus, displaying the killer phenotype
    Medical and Veterinary Entomology, 2015
    Co-Authors: Elena Martin, Gioia Bongiorno, Luigi Gradoni, Laura Giovati, Matteo Montagna, E.e Crotti, C.f Damiani, Luciano Polonelli, Guido Favia
    Abstract:

    The yeast Wickerhamomyces anomalus has been studied for its wide biotechnological potential, mainly for applications in the food industry. Different strains of W. anomalus have been isolated from diverse habitats and recently from insects, including mosquitoes of medical importance. This paper reports the isolation and phylogenetic characterization of W. anomalus from laboratory-reared adults and larvae of Phlebotomus Perniciosus (Diptera: Psychodidae), a main phlebotomine vector of human and canine leishmaniasis. Of 65 yeast strains isolated from P. Perniciosus, 15 strains were identified as W. anomalus; one of these was tested for the killer phenotype and demonstrated inhibitory activity against four yeast sensitive strains, as reported for mosquito-isolated strains. The association between P. Perniciosus and W. anomalus deserves further investigation in order to explore the possibility that this yeast may exert inhibitory/killing activity against Leishmania spp.

  • de novo assembly and sex specific transcriptome profiling in the sand fly Phlebotomus Perniciosus diptera phlebotominae a major old world vector of leishmania infantum
    BMC Genomics, 2015
    Co-Authors: Valeria Petrella, Gioia Bongiorno, Serena Aceto, Francesco Musacchia, Vincenza Colonna, Mark D Robinson, Vladimir Benes, G Cicotti, Luigi Gradoni
    Abstract:

    The phlebotomine sand fly Phlebotomus Perniciosus (Diptera: Psychodidae, Phlebotominae) is a major Old World vector of the protozoan Leishmania infantum, the etiological agent of visceral and cutaneous leishmaniases in humans and dogs, a worldwide re-emerging diseases of great public health concern, affecting 101 countries. Despite the growing interest in the study of this sand fly species in the last years, the development of genomic resources has been limited so far. To increase the available sequence data for P. Perniciosus and to start studying the molecular basis of the sexual differentiation in sand flies, we performed whole transcriptome Illumina RNA sequencing (RNA-seq) of adult males and females and de novo transcriptome assembly. We assembled 55,393 high quality transcripts, of which 29,292 were unique, starting from adult whole body male and female pools. 11,736 transcripts had at least one functional annotation, including full-length low abundance salivary transcripts, 981 transcripts were classified as putative long non-coding RNAs and 244 transcripts encoded for putative novel proteins specific of the Phlebotominae sub-family. Differential expression analysis identified 8590 transcripts significantly biased between sexes. Among them, some show relaxation of selective constraints when compared to their orthologs of the New World sand fly species Lutzomyia longipalpis. In this paper, we present a comprehensive transcriptome resource for the sand fly species P. Perniciosus built from short-read RNA-seq and we provide insights into sex-specific gene expression at adult stage. Our analysis represents a first step towards the identification of sex-specific genes and pathways and a foundation for forthcoming investigations into this important vector species, including the study of the evolution of sex-biased genes and of the sexual differentiation in phlebotomine sand flies.

Gioia Bongiorno - One of the best experts on this subject based on the ideXlab platform.

  • elevated and sustained anti feeding effect of scalibor deltamethrin collar against the sand fly Phlebotomus Perniciosus in dogs confirmed for 1 year following treatment
    Medical and Veterinary Entomology, 2021
    Co-Authors: A Evans, Gioia Bongiorno, Cristina Khoury, Riccardo Bianchi, J J Fourie, N Lekouch, E Thomas, R Chiummo, L. Gradoni
    Abstract:

    Dogs are reservoir hosts for Leishmania infantum, a protozoan parasite transmitted by phlebotomine sand flies. The anti-feeding and fast-killing efficacy of Scalibor® deltamethrin collars against experimental Phlebotomus Perniciosus challenges on dogs was determined over 1 year. Two groups of 8 dogs each were fitted with placebo (control) or deltamethrin collars (treated) on Day 0 and exposed to sand flies approximately every 28 days up to Day 364. After each exposure, anti-feeding and fast-killing efficacy rates were determined by comparing blood-fed or live insects, respectively, in the treated vs. the control group. Blood-fed and live sand flies were significantly less in treated dogs as compared to control dogs at each assessment. The anti-feeding efficacy rate exceeded 90% except on Day 337 (89%) but increased again (96%) on Day 364. Fast killing efficacy was <74% over the study when considering all flies. However, this value increased cumulatively to 98% when only blood-fed flies were compared between groups. Scalibor® collars are highly effective at preventing P. Perniciosus blood-feeding and in fast-killing flies taking a blood meal for up to 1 year after application. These strong and long-lasting effects are an important strategic component for L. infantum transmission control.

  • examining the relationship of clinical and laboratory parameters with infectiousness to Phlebotomus Perniciosus and its potential infectivity in dogs with overt clinical leishmaniasis
    Frontiers in Veterinary Science, 2021
    Co-Authors: Manuela Gizzarelli, Gioia Bongiorno, Riccardo Bianchi, Valentina Foglia Manzillo, Antonio Bosco, Daniela Giaquinto, Nour El Houda Ben Fayala, Marie Varloud, Alessia Crippa, Luigi Gradoni
    Abstract:

    Infected dogs are considered the main domestic animal reservoirs for Leishmania infantum parasite. Infectiousness to competent phlebotomine vectors has been associated with many factors, the main being the severity of the disease exhibited by infected dogs. This study examines the relationship between different clinical parameters and the infectiousness to colonized Phlebotomus Perniciosus sand flies having a blood meal on dogs. Data obtained in the present study come from an untreated group of Leishmania sick dogs submitted to xenodiagnosis for the evaluation of a spot on insecticide solution. Seventeen dogs were diagnosed as affected by leishmaniasis through clinical examination, immunofluorescence antibody test (IFAT) serology, and loop-mediated isothermal amplification (LAMP). The disease severity (clinical score) was staged by using a numeric value derived from eight clinical and parasitological parameters. Xenodiagnosis was performed on caged dogs exposed for 1.5 h to sand-fly bites. The following parameters related to sand flies were examined: blood feeding (% of blood engorged females), promastigote detection (% of promastigote-positive sand flies), promastigote burden, and the promastigote stage maturation (potential transmissibility rate). Statistical relationship between the clinical score and entomological parameters was investigated, as well as the possible correlation between each clinical and laboratory parameters and sand fly infection/infectivity. The severity of clinical score may influence the blood feeding by, and the probability of promastigote detection in, sand flies; skin lesions seem to be the main factor that influences the rate of blood feeding. Promastigote burden is related to IFAT titer, skin lesions, and clinical score. All entomological parameters are strongly related among them. This study confirms that both P. Perniciosus infection and infectivity are influenced by a dog's clinical condition.

  • a single oral dose of fluralaner bravecto in dogs rapidly kills 100 of blood fed Phlebotomus Perniciosus a main visceral leishmaniasis vector for at least 1 month after treatment
    Medical and Veterinary Entomology, 2020
    Co-Authors: Gioia Bongiorno, Cristina Khoury, Riccardo Bianchi, A Evans, N Lekouch, E Thomas, R Chiummo, L Meyer, L. Gradoni
    Abstract:

    Dogs are the reservoir host of zoonotic visceral leishmaniasis (VL) caused by Leishmania infantum (Kinetoplastida: Trypanosomatidae). Both subclinically-infected and sick animals can be infectious to competent phlebotomine vectors. The degree and duration of insecticidal efficacy of an oral dose of fluralaner (Bravecto®; Merck Animal Health) was determined in dogs exposed to bites of Phlebotomus Perniciosus (Diptera: Psychodidae), a main Mediterranean vector of VL. Twelve dogs allocated to two groups of six animals each were included in a parallel-group designed, negative-controlled, randomized, blinded, single-centre efficacy study. Group 2 was treated with fluralaner on day 0, and sand-fly exposure of both groups was performed on days 1, 28 and 84. Viability of blood-fed females was assessed up to 96 h after exposure and efficacy was measured as the survival rate of specimens fed on Group 2 versus those fed on Group 1. A mortality of 100% was recorded at 24 h in females fed on Group 2 at both days 1 and 28. Significant insecticidal efficacy was still observed on day 84, with > 50% mortality recorded by 48 h post blood meal in Group 2. Fluralaner treatment of dogs represents a promising and affordable method for reducing the pool of infected vectors in endemic settings of zoonotic VL.

  • laboratory transmission of an asian strain of leishmania tropica by the bite of the southern european sand fly Phlebotomus Perniciosus
    International Journal for Parasitology, 2019
    Co-Authors: Gioia Bongiorno, Trentina Di Muccio, Marina Gramiccia, Riccardo Bianchi, Luigi Gradoni
    Abstract:

    Imported cases of anthroponotic cutaneous leishmaniasis due to Leishmania tropica are increasingly documented in Europe. We investigated the ability of Phlebotomus Perniciosus, a competent vector of Leishmania infantum widespread in southwestern Europe, to support the growth and transmissibility of an Asian strain of L. tropica recently isolated from a refugee. Parasite growth behavior was investigated in laboratory-reared sand flies fed artificially with promastigotes as well as in sand flies infected after biting on footpad lesions induced in hamsters by promastigote inoculation. The evolution of infection was checked by gut microscopy and quantitative real-time PCR, and it was found to be similar between promastigote- and amastigote-initiated infections. In 80% of infected sand flies, despite survival and flourishing growth of promastigotes after blood digestion and defecation, either the parasites died, or failed to migrate to the foregut and/or to mature into infective forms. However, in the remaining 20% L. tropica developed into abundant metacyclic promastigotes. The quantitative real-time PCR assay detected variable loads of gut promastigotes irrespective of morphological evidence of viability or progressive/final death. Parasite transmissibility was investigated by exposing naive hamsters to P. Perniciosus previously infected on chronic lesions induced in hamsters which survived to take a second blood meal. Two months post exposure, lesions developed in skin sites bitten by sand flies confirmed to harbor metacyclic promastigotes; in the following months, the presence of viable and transmissible L. tropica parasites in lesions was demonstrated by xenodiagnosis assays. Our findings support the hypothesis that, in particular epidemiological situations, P. Perniciosus may play the role of an occasional L. tropica vector.

  • The mycobiota of the sand fly Phlebotomus Perniciosus: Involvement of yeast symbionts in uric acid metabolism.
    Environmental microbiology, 2018
    Co-Authors: Elena Martin, Gioia Bongiorno, Luigi Gradoni, Matteo Montagna, L. De Marco, P. Mensah, Ilaria Varotto Boccazzi, Luciano Sacchi, Irene Ricci, Claudio Bandi
    Abstract:

    The knowledge of the fungal mycobiota of arthropods, including the vectors of human and animal diseases, is still limited. Here, the mycobiota associated with the sand fly Phlebotomus Perniciosus, the main vector of leishmaniasis in the western Mediterranean area, by a culture-dependent approach (microbiological analyses and sequencing of the 26S rRNA gene), internal transcribed spacer (ITS) rRNA amplicon-based next-generation sequencing, fluorescence in situ hybridisation (FISH), and genome sequencing of the dominant yeast species was investigated. The dominant species was Meyerozyma guilliermondii, known for its biotechnological applications. The focus was on this yeast and its prevalence in adults, pupae and larvae of reared sand flies (overall prevalence: 57.5%) and of field-collected individuals (overall prevalence: 9%) was investigated. Using whole-mount FISH and microscopic examination, it was further showed that M. guilliermondii colonizes the midgut of females, males and larvae and the distal part of Malpighian tubules of female sand flies, suggesting a possible role in urate degradation. Finally, the sequencing and analysis of the genome of M. guilliermondii allowed predicting the complete uric acid degradation pathway, suggesting that the yeast could contribute to the removal of the excess of nitrogenous wastes after the blood meal of the insect host.