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1.
Vet Pathol ; 57(1): 139-146, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31662046

RESUMO

With the aim of evaluating the presence of Fusarium spp. in sea turtles with and without lesions and assessing the risk factors favoring colonization and/or infection, 74 loggerhead sea turtles (Caretta caretta) admitted to rescue and rehabilitation clinics in Italy were analyzed. The study compared 31 individuals with no apparent macroscopic lesions and 43 individuals with macroscopic lesions. Shell and skin samples were analyzed using Calcofluor white with 10% potassium hydroxide, standard histopathological examination, and fungal cultures. Fusarium spp. were isolated more frequently from animals with superficial lesions (39%) than from those with no macroscopic lesions (16%). Isolates from animals with superficial lesions were Fusarium solani species complex (FSSC) lineages haplotypes 9, 12, and 27 (unnamed lineages), FSSC-2 (Fusarium keratoplasticum), Fusarium oxysporum (27%), and Fusarium brachygibbosum (3%). In contrast, only F. solani haplotypes 9 and 12 were isolated from animals with no macroscopic lesions. The presence of lesions was identified as a risk factor for the occurrence of Fusarium spp. Of the 74 animals, only 7 (9.5%) scored positive on microscopic examination with Calcofluor, and histological examination of those 7 animals revealed necrosis, inflammatory cells, and fungal hyphae in the carapace and skin. The results of this study suggest that fusariosis should be included in the differential diagnosis of shell and skin lesions in sea turtles. Direct examination using Calcofluor and potassium hydroxide was not useful to diagnose the infection. Histopathological examination and fungal culture should be performed to ensure correct treatment and infection control.


Assuntos
Fusariose/veterinária , Fusarium/isolamento & purificação , Necrose/veterinária , Tartarugas/microbiologia , Exoesqueleto/microbiologia , Exoesqueleto/patologia , Animais , Feminino , Fusariose/microbiologia , Fusariose/patologia , Hifas , Itália , Masculino , Necrose/microbiologia , Necrose/patologia , Pele/microbiologia , Pele/patologia
2.
J Med Microbiol ; 63(Pt 11): 1467-1473, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25168965

RESUMO

Fungaemia caused by Malassezia spp. in hospitalized patients requires prompt and appropriate therapy, but standard methods for the definition of the in vitro antifungal susceptibility have not been established yet. In this study, the in vitro susceptibility of Malassezia furfur from bloodstream infections (BSIs) to amphotericin B (AMB), fluconazole (FLC), itraconazole (ITC), posaconazole (POS) and voriconazole (VRC) was assessed using the broth microdilution (BMD) method of the Clinical and Laboratory Standards Institute (CLSI) with different media such as modified Sabouraud dextrose broth (SDB), RPMI and Christensen's urea broth (CUB). Optimal broth media that allow sufficient growth of M. furfur, and produce reliable and reproducible MICs using the CLSI BMD protocol were assessed. Thirty-six M. furfur isolates collected from BSIs of patients before and during AMB therapy, and receiving FLC prophylaxis, were tested. A good growth of M. furfur was observed in RPMI, CUB and SDB at 32 °C for 48 and 72 h. No statistically significant differences were detected between the MIC values registered after 48 and 72 h incubation. ITC, POS and VRC displayed lower MICs than FLC and AMB. These last two antifungal drugs showed higher and lower MICs, respectively, when the isolates were tested in SDB. SDB is the only medium in which it is possible to detect isolates with high FLC MICs in patients receiving FLC prophylaxis. A large number of isolates showed high AMB MIC values regardless of the media used. In conclusion, SDB might be suitable to determine triazole susceptibility. However, the media, the drug formulation or the breakpoints herein applied might not be useful for assessing the AMB susceptibility of M. furfur from BSIs.


Assuntos
Antifúngicos/farmacologia , Farmacorresistência Fúngica , Fungemia/microbiologia , Malassezia/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana
3.
Med Mycol ; 51(8): 863-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23834283

RESUMO

Antifungal resistance has been associated with biofilm formation in many microorganisms, but not yet in Malassezia pachydermatis. This saprophytic yeast can cause otitis and dermatitis in dogs and has emerged as an important human pathogen, responsible for systemic infections in neonates in intensive care units. This study aims to evaluate the in vitro antifungal susceptibility of M. pachydermatis strains, in both their planktonic and sessile forms, to fluconazole, miconazole, ketoconazole, itraconazole, posaconazole, terbinafine and voriconazole using the XTT assay and Clinical and Laboratory Standards Institute (CLSI) microdilution method. The minimum inhibitory concentration (MIC) values recorded for each drug were significantly higher for sessile cells relative to planktonic cells to the extent that ≥ 90% of M. pachydermatis strains in their sessile form were classified as resistant to all antifungal agents tested. Data suggest that M. pachydermatis biofilm formation is associated with antifungal resistance, paving the way towards investigating drug resistance mechanisms in Malassezia spp.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Fúngica , Malassezia/efeitos dos fármacos , Malassezia/fisiologia , Animais , Dermatomicoses/microbiologia , Dermatomicoses/veterinária , Cães , Humanos , Malassezia/isolamento & purificação , Testes de Sensibilidade Microbiana
4.
Vet Microbiol ; 167(1-2): 215-34, 2013 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-23428378

RESUMO

Among diseases of horses caused by fungi (=mycoses), dermatophytosis, cryptococcosis and aspergillosis are of particular concern, due their worldwide diffusion and, for some of them, zoonotic potential. Conversely, other mycoses such as subcutaneous (i.e., pythiosis and mycetoma) or deep mycoses (i.e., blastomycosis and coccidioidomycosis) are rare, and/or limited to restricted geographical areas. Generally, subcutaneous and deep mycoses are chronic and progressive diseases; clinical signs include extensive, painful lesions (not pathognomonic), which resemble to other microbial infections. In all cases, early diagnosis is crucial in order to achieve a favorable prognosis. Knowledge of the epidemiology, clinical signs, and diagnosis of fungal diseases is essential for the establishment of effective therapeutic strategies. This article reviews the clinical manifestations, diagnosis and therapeutic protocols of equine fungal infections as a support to early diagnosis and application of targeted therapeutic and control strategies.


Assuntos
Doenças dos Cavalos , Micoses/veterinária , Animais , Fungos/fisiologia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/microbiologia , Cavalos , Micoses/diagnóstico , Micoses/tratamento farmacológico , Micoses/epidemiologia , Micoses/microbiologia
5.
Med Mycol ; 51(2): 136-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22686247

RESUMO

The few studies attempting to specifically characterize dermatophytes from hair samples of dogs and cats using PCR-based methodology relied on sequence-based analysis of selected genetic markers. The aim of the present investigation was to establish and evaluate a PCR-based approach employing genetic markers of nuclear DNA for the specific detection of dermatophytes on such specimens. Using 183 hair samples, we directly compared the test results of our one-step and nested-PCR assays with those based on conventional microscopy and in vitro culture techniques (using the latter as the reference method). The one step-PCR was highly accurate (AUC > 90) for the testing of samples from dogs, but only moderately accurate (AUC = 78.6) for cats. A nested-PCR was accurate (AUC = 93.6) for samples from cats, and achieved higher specificity (94.1 and 94.4%) and sensitivity (100 and 94.9%) for samples from dogs and cats, respectively. In addition, the nested-PCR allowed the differentiation of Microsporum canis from Trichophyton interdigitale (zoophilic) and geophilic dermatophytes (i.e., Microsporum gypseum or Trichophyton terrestre), which was not possible using the one step-assay. The PCRs evaluated here provide practical tools for diagnostic applications to support clinicians in initiating prompt and targeted chemotherapy of dermatophytoses.


Assuntos
Arthrodermataceae/isolamento & purificação , Doenças do Gato/diagnóstico , Doenças do Cão/diagnóstico , Reação em Cadeia da Polimerase/métodos , Tinha/veterinária , Animais , Arthrodermataceae/genética , Doenças do Gato/microbiologia , Gatos , Quitina Sintase/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Doenças do Cão/microbiologia , Cães , Proteínas Fúngicas/genética , Marcadores Genéticos/genética , Cabelo/microbiologia , Itália , Microsporum/genética , Microsporum/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pele/patologia , Especificidade da Espécie , Tinha/diagnóstico , Tinha/microbiologia , Trichophyton/genética , Trichophyton/isolamento & purificação
6.
Vet Microbiol ; 160(1-2): 126-31, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-22682201

RESUMO

Yeasts of the genus Malassezia are commensals of the normal skin microbial flora of humans and animals. These yeasts may become pathogenic under certain circumstances and their pathogenic role may be related to host immune system as well to yeast virulence factors (e.g., phospholipase production and biofilm formation). This study aims to evaluate the in vitro ability of M. pachydermatis strains to produce biofilm, and its relationship with phospholipase activity and the genetic make-up of isolates from lesioned (n=32) and healthy (n=30) dog skin. The production of biofilm was determined by crystal violet staining and scanning electronic microscopy (SEM). Biofilm was produced by almost all M. pachydermatis isolates (95.2%) from dogs with and without skin lesions at variable level and different structure. At the SEM, biofilm matrix presented adhering blastoconidia clustered in multi- or monolayer structures with variable quantity of extracellular production. Of the three genotypes detected, genotype B showed the lowest ability to produce biofilm. Of the 59 isolates producing biofilm, 33 (55.9%) produced phospholipase, with a higher biofilm formation (p<0.05) in strains collected from animals with skin lesions. It is here suggested that phospholipase production might act in synergism with the biofilm formation by inducing or exacerbating skin lesions in dogs. The results provide evidences for a better understanding of the interactions between yeasts and host immune system, toward revealing the pathogenicity of M. pachydermatis in animals.


Assuntos
Biofilmes , Dermatomicoses/veterinária , Doenças do Cão/microbiologia , Malassezia/fisiologia , Animais , Dermatomicoses/microbiologia , Cães , Genótipo , Malassezia/enzimologia , Malassezia/genética , Malassezia/isolamento & purificação , Fosfolipases/metabolismo
7.
Vet Microbiol ; 159(3-4): 536-40, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-22622336

RESUMO

The microdilution antifungal method (CLSI BMD, M27-A3) was used for testing the antifungal susceptibility of Malassezia species. However, optimal broth media that allow sufficient growth of M. pachydermatitis and produce reliable and reproducible MICs using the CLSI BMD protocol are yet to be established. In this study, the susceptibility of M. pachydermatis isolates to ketoconazole (KTZ), itraconazole (ITZ) and fluconazole (FLZ) was evaluated in vitro by the CLSI BMD test using Christensen's urea broth (CUB) and mRPMI 1640 containing lipid supplementation, Sabouraud dextrose broth with 1% tween 80 (SDB), and Dixon broth (DXB). A FLZ-resistant M. pachydermatis was generated in vitro and tested under the same conditions. A good growth of M. pachydermatis incubated for 48 and 72 h, respectively, was observed in CUB, SDB and DXB and not in mRPMI 1640 (p<0.001). No statistically significant differences were detected between the MIC values registered after 48 h and 72 h incubation. ITZ displayed lower MIC values than KTZ and FLZ regardless of the media employed. A large number of FLZ-resistant Malassezia strains (86.6%) was observed using DXB. A MIC>64 mg/L was observed only when the FLZ-resistant M. pachydermatis isolate was tested in SDB. Based on the results obtained herein, culture in SDB, stock inoculum suspensions of 1-5 × 10(6)CFU/ml, and an incubation time of 48 h are proposed as optimal conditions for the evaluation of the in vitro antifungal susceptibility of M. pachydermatis using a modified CLSI BMD protocol.


Assuntos
Antifúngicos/farmacologia , Malassezia/efeitos dos fármacos , Malassezia/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana/métodos , Meios de Cultura , Dermatomicoses/microbiologia , Dermatomicoses/veterinária , Malassezia/isolamento & purificação
8.
Med Mycol ; 50(8): 795-801, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22471886

RESUMO

Dermatitis caused by Malassezia spp., one of most common skin disease in dogs, requires prolonged therapy and/or high doses of antifungal agents. In the present study, the antifungal susceptibility of M. pachydermatis to ketoconazole (KTZ), fluconazole (FLZ), itraconazole (ITZ), posaconazole (POS) and voriconazole (VOR) was evaluated in vitro using both CLSI reference broth microdilution (CLSI BMD) and E-test. A total of 62 M. pachydermatis strains from dogs with and without skin lesions were tested. M. pachydermatis strains were susceptible to ITZ, KTZ and POS using both test methods, with the highest MIC found in tests of FLZ. Essential agreement between the two methods ranged from 87.1% (VOR) to 91.9% (ITZ), and categorical agreement from 74.2% (FLZ) to 96.8% (ITZ). Minor error discrepancies were observed between the two methods, with major discrepancies observed for KTZ. A higher MIC(50) value for FLZ was noted with M. pachydermatis genotype B. The MICs(50) of M. pachydermatis genotype B for KTZ, VOR and POS were higher in isolates from dogs with skin lesions than those in isolates from animals without skin lesions. The results suggest a link between genotypes of M. pachydermatis and in vitro drug susceptibility. The categorical agreement for both E-test and CLSI BMD methods found in this investigation confirms the E-test as a reliable diagnostic method for routine use in clinical mycology laboratories.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Malassezia/efeitos dos fármacos , Animais , Cães , Testes de Sensibilidade Microbiana/métodos
9.
Vet Microbiol ; 155(2-4): 395-8, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-21962411

RESUMO

Canine Malassezia dermatitis is frequently treated with systemic ketoconazole (KTZ) and itraconazole (ITZ). However, no information is available on the antifungal susceptibility to azoles and allilamine of Malassezia pachydermatis isolates from dogs with or without skin lesions. The present study was designed to evaluate the in vitro antifungal susceptibility of M. pachydermatis strains from dogs with or without skin lesions to KTZ, ITZ, miconazole (MICO), fluconazole (FLZ), posaconazole (POS), voriconazole (VOR) and terbinafine (TER) using the Clinical and Laboratory Standards Institute reference Broth Microdilution Method (CLSI M27-A2). The association between the susceptibility to antifungal compounds and the origin of M. pachydermatis, from skin with or without lesions has been also assessed. A total of 62 M. pachydermatis strains from healthy dogs (i.e., Group A=30) or with skin lesions (i.e., Group B=32) were tested. ITZ, KTZ and POS showed the highest activity against M. pachydermatis strains, whereas MICO TER and FLZ the lowest. A higher number of Malassezia resistant strains were registered among isolates from Group B than those from Group A. This study indicates that M. pachydermatis strains were susceptible to ITZ, KTZ, and POS. However, dogs with lesions may harbour strains with low susceptibility to antifungal agents and displaying cross-resistance phenomena to azole. The antifungal therapy in Malassezia infections requires careful appraisal of choice of drugs especially in cases of unresponsiveness to antifungal treatment or recurrent infections.


Assuntos
Antifúngicos/farmacologia , Dermatomicoses/veterinária , Doenças do Cão/microbiologia , Malassezia/efeitos dos fármacos , Triazóis/farmacologia , Animais , Dermatomicoses/microbiologia , Cães , Fluconazol/farmacologia , Itraconazol/farmacologia , Cetoconazol/farmacologia , Malassezia/isolamento & purificação , Miconazol/farmacologia , Naftalenos/farmacologia , Pirimidinas/farmacologia , Terbinafina , Voriconazol
10.
Mycoses ; 55(1): 45-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22175244

RESUMO

Microsporum canis and Trichophyton mentagrophytes are zoophilic dermatophytes which can cause skin infections in animals and humans. The clinical expression of this infection strongly varies depending on host, fungal species as well as enzyme production. No comparative studies are available on the enzymatic activities of M. canis and T. mentagrophytes isolated from breeding rabbits. Thus, the aim of this work was to assess the capability of M. canis and T. mentagrophytes isolated from rabbits both with and without lesions in producing different enzymes. The relationship of dermatophyte enzymatic activities and presence/absence of skin lesions has also been investigated. A total of 260 isolates of T. mentagrophytes and 25 isolates of M. canis sampled both from healthy and lesioned skin of rabbits, as well as from air samples of positive farms were examined. The results showed that T. mentagrophytes and M. canis from rabbits produce different enzymes. However, only elastase and gelatinase were linked to the appearance of lesions in T. mentagrophytes infections, whereas lipase in those by M. canis.


Assuntos
Microbiologia do Ar , Dermatomicoses/microbiologia , Microsporum/enzimologia , Coelhos/microbiologia , Trichophyton/enzimologia , Animais , Dermatomicoses/veterinária , Ativação Enzimática , Gelatinases/metabolismo , Lipase/metabolismo , Microsporum/isolamento & purificação , Microsporum/metabolismo , Elastase Pancreática/metabolismo , Trichophyton/isolamento & purificação , Trichophyton/metabolismo
11.
Vet Microbiol ; 154(3-4): 395-402, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-21840652

RESUMO

Little information is available on the molecular epidemiology of dermatophytoses in rabbit farms and farm workers. A total of 117 isolates belonging to the Trichophyton mentagrophytes complex and 21 isolates of Microsporum canis were collected from rabbits with or without skin lesions, air samples of farms known to harbour these pathogens, and from farm workers with skin lesions, and molecularly characterized. Sequencing of amplicons from the T. mentagrophytes complex and M. canis isolates revealed the presence of one sequence-type for both partial chitin synthase-1 gene (pchs-1) and ribosomal internal transcribed spacer (ITS+), respectively. On the basis of comparative sequence analyses, isolated representing the T. mentagrophytes complex were molecularly identified as Trichophyton interdigitale (zoophilic) Priestley. The M. canis and T. interdigitale pchs-1 sequences herein analysed were 100% homologous to known sequences from different hosts (i.e., cats, dogs, humans and rabbits). Conversely, the ITS+ sequences of T. interdigitale from dogs, pigs and mice were identical, but displayed up to 8.6% difference with those from humans, guinea pigs and rabbits. The results of this study suggest that environmental and clinical isolates of T. interdigitale (zoophilic) and M. canis might share a common origin. Interestingly, the close phylogenetic relationship between T. interdigitale (zoophilic) strains and isolates from dogs, pigs and mice might indicate that these animals represented a reservoir of dermatophyte infection in rabbit farms. These animal species should therefore be considered when setting up control protocols to prevent infections by dermatophytes and their zoonotic transmission.


Assuntos
Microsporum/genética , Tinha/microbiologia , Adulto , Criação de Animais Domésticos , Animais , Sequência de Bases , Quitina Sintase/genética , Dermatomicoses/epidemiologia , Dermatomicoses/microbiologia , Dermatomicoses/veterinária , Feminino , Genes Fúngicos , Humanos , Masculino , Microsporum/classificação , Microsporum/isolamento & purificação , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Coelhos , Tinha/epidemiologia , Tinha/veterinária
12.
Mol Cell Probes ; 25(1): 1-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21193026

RESUMO

Members of the genus Malassezia are lypophilic and/or lipid-dependent, unipolar budding yeasts that can become pathogenic under the influence of particular predisposing factors (e.g., changes in the cutaneous microenvironment and/or alterations in host defences). This genus comprises at least 14 species, which have been identified traditionally based on their morphology and biochemical features. However, phenetic characteristics often do not allow the identification or delineation of closely related Malassezia spp., such that molecular tools need to be used to assist in fundamental studies of the epidemiology and ecology of Malassezia as well as aspects of the pathogenesis and disease caused by members of this genus. This article briefly reviews the morphological and biochemical methods commonly used for the identification of Malassezia as well as DNA technological methods that have been established for the specific identification of members of this genus and the diagnosis of their infections. New avenues for the development of improved molecular-diagnostic methods to overcome diagnostic limitations and to underpin fundamental investigations of this interesting group of yeasts are proposed.


Assuntos
Dermatomicoses/diagnóstico , Malassezia/classificação , Meios de Cultura , Impressões Digitais de DNA , DNA Fúngico/genética , DNA Ribossômico/genética , Dermatomicoses/microbiologia , Marcadores Genéticos , Variação Genética , Genoma Fúngico , Humanos , Malassezia/genética , Malassezia/metabolismo , Análise de Sequência de DNA
13.
Vet Microbiol ; 148(2-4): 368-71, 2011 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20970928

RESUMO

Fungi of the genus Geotrichum are commonly found in the environment and, in some circumstances, they may cause diseases in humans and animals. Although these fungi have been isolated from skin lesions of some animal species, their pathogenic role in horses remains uncertain. With the aim to investigate the role of Geotrichum candidum as etiological agent of dermatomycoses, a retrospective study of 64 horses presenting skin lesions and suspected to have fungal infections was carried out. For each animal, anamnestic data were recorded and fungal culture were performed using hair. Out of 64 cases, 18 (28.1%) were positive for G. candidum and only two (3.1%) for dermatophytes (i.e., one for Microsporum equinum and the other for Microsporum canis). Alopecia, desquamation, and pruritus localized mainly on head and neck were frequently observed in G. candidum infected animals. Most of G. candidum infections were recorded during spring (44.4%). Out of the 18 animals presenting G. candidum infections, eight were treated using a disinfectant with antifungal properties. After one month of treatment, the clinical lesions were healed and fungal cultures resulted negative. The high prevalence of G. candidum in skin lesions of horses and the clinical recover following antifungal treatment indicated that these yeast-like fungi might play a role as etiological agents of horse cutaneous mycoses.


Assuntos
Dermatomicoses/veterinária , Geotrichum/isolamento & purificação , Doenças dos Cavalos/microbiologia , Cavalos/microbiologia , Animais , Antifúngicos/uso terapêutico , Arthrodermataceae/isolamento & purificação , Dermatomicoses/tratamento farmacológico , Dermatomicoses/microbiologia , Feminino , Geotrichum/patogenicidade , Doenças dos Cavalos/tratamento farmacológico , Masculino , Estudos Retrospectivos , Pele/microbiologia
14.
Parasitology ; 138(4): 527-36, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21078221

RESUMO

OBJECTIVE: Rhipicephalus sanguineus is the most widespread tick in the world and a vector of many pathogens infecting dogs and humans. To date, there have been no investigations on the biology of R. sanguineus under natural Mediterranean climatic conditions. METHODS: The biology of R. sanguineus was studied under laboratory and natural climatic conditions in southern Italy. Several biological parameters were compared in different seasons, and their correlation with climatic data was assessed. RESULTS: The life cycle of R. sanguineus lasted for a mean of 101·4 and 116·2 days under laboratory and environmental conditions respectively. Reproductive parameters of wild-collected females kept in the environment in May were significantly different from first-generation females maintained in September-October, and the correlation between reproductive parameters and climate data varied according to season. CONCLUSION: These results indicate that the Mediterranean climate affects the biology of R. sanguineus, which compensates its losses during the initial phases of its cycle in spring with high feeding and moulting rates of larvae and nymphs during summer as well as with high egg production during autumn. These results advance our knowledge of the biology of R. sanguineus and will be useful for the understanding of the eco-epidemiology of tick-borne diseases that this tick transmits.


Assuntos
Vetores Aracnídeos/fisiologia , Clima , Estágios do Ciclo de Vida/fisiologia , Rhipicephalus sanguineus/fisiologia , Infestações por Carrapato/veterinária , Animais , Vetores Aracnídeos/genética , Vetores Aracnídeos/crescimento & desenvolvimento , Cães , Feminino , Humanos , Umidade , Itália/epidemiologia , Masculino , Oviposição , Filogenia , Coelhos , Reprodução/fisiologia , Rhipicephalus sanguineus/genética , Rhipicephalus sanguineus/crescimento & desenvolvimento , Estações do Ano , Razão de Masculinidade , Temperatura , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Fatores de Tempo
15.
Vet Parasitol ; 170(3-4): 313-7, 2010 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-20227186

RESUMO

A community-based epidemiological study was carried out in a rural area in northeastern Brazil, where visceral leishmaniasis is endemic, but the primary vector Lutzomyia longipalpis has never been found. Forty-one dogs were screened by an indirect immunofluorescence antibody test (IFAT) for the presence of anti-Leishmania antibodies and 12 (29.3%) of them were positive. One of the IFAT-positive dogs was also positive for Leishmania amastigotes in bone marrow cytology and for Leishmania infantum by real-time polymerase chain reaction (PCR) on blood. One IFAT-negative dog was positive for L. infantum by PCR on bone marrow and other for Leishmania amastigotes in skin stained-smears. When tested for L. braziliensis by PCR, 20 dogs were positive. Considering all diagnostic tests, the estimated prevalence of Leishmania spp. infection in the studied rural dog population was 58.5%. There was no significant difference in IFAT-positivity in relation to age, gender, and clinical status of the dogs. When tested for L. infantum by real-time PCR, 20 ticks collected from IFAT-positive dogs were all negative. This study shows a high level of exposure to Leishmania spp. infection in dogs from a rural community in northeastern Brazil. In general, the results do not support the participation of ticks as vectors of L. infantum in this area, which is likely to be transmitted by Lutzomyia spp. other than L. longipalpis. Finally, this study highlights that the use of IFAT in areas where both L. infantum and L. braziliensis are present should be withdraw in order to avoid the unnecessary culling of dogs that are actually infected only by L. braziliensis.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Cutânea/veterinária , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Cães , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Leishmania infantum/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Leishmaniose Visceral/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Carrapatos/parasitologia
16.
Exp Parasitol ; 125(2): 184-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20138871

RESUMO

Phlebotomine sand flies are the only proven biological vectors of Leishmania parasites. However, Rhipicephalus sanguineus ticks have long been suspected to transmit Leishmania infantum in studies carried out in laboratory and natural conditions. In the present study, 5 microl of L. infantum promastigotes (1x10(6) cells per ml) was injected into the hemocel through the coxa I of four engorged females (F1, F2, F3 and F4). Control ticks (F5 and F6) were injected with sterile phosphate-buffered saline (PBS) using the same procedure. Then, these females, their eggs, and the originated larvae were tested by real time polymerase chain reaction (real-time PCR) for the presence of L. infantum kinetoplast DNA (kDNA). Females and eggs were tested after the end of the oviposition period (about 5 weeks post-inoculation) whereas larvae were tested about 4 months after the inoculation of females. All artificially infected females were positive for L. infantum kDNA. In addition, two pools of eggs (one from F2 and other from F4) and four pools of larvae (one from each F1 and F4 and two from F2) were positive for L. infantum kDNA. These results showed, for the first time, the transovarial passage of L. infantum kDNA in R. sanguineus ticks, thus suggesting that the transovarial transmission of L. infantum protozoa in ticks is worth to be investigated.


Assuntos
Vetores Aracnídeos/parasitologia , DNA de Cinetoplasto/isolamento & purificação , Leishmania infantum/genética , Rhipicephalus sanguineus/parasitologia , Animais , Feminino , Larva/parasitologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/transmissão , Óvulo/parasitologia , Reação em Cadeia da Polimerase
17.
Parasitol Res ; 106(4): 857-60, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20127362

RESUMO

Canine leishmaniosis is a widespread disease caused by Leishmania parasites, which are transmitted by phlebotomine sand flies. However, in some areas where canine leishmaniosis is endemic, but the primary vectors have not been found, ticks have been suspected to play a role in transmitting the infection. Herewith, we report the detection of Leishmania infantum kinetoplast minicircle DNA (kDNA) in ticks collected from naturally infected dogs living in rural areas of Southern Italy (site A) and Northeastern Brazil (site B). Between March and October 2007, ticks were collected from 26 dogs positive to anti-Leishmania antibodies (one from site A and 25 from site B) and either placed directly into vials containing 70% ethanol or maintained alive for identification and subsequent dissection. All the 95 ticks collected were morphologically identified as Rhipicephalus sanguineus. After identification, their genomic DNA was extracted (either individually or in pools) and processed by polymerase chain reaction (PCR) for the detection of L. infantum kDNA. Two pools of salivary glands from ticks (one from five females and other from five males) found on a dog from site A and tested by a conventional PCR were positive. Amplicon sequencing confirmed the identity of the parasite. In addition, nine (12.3%) out of the 73 ticks found on dogs from site B and tested by a real-time PCR were positive, with a low parasite load (less than 1 parasite/ml). The retrieval of L. infantum kDNA in salivary glands of R. sanguineus ticks has been here reported for the first time. Therefore, further studies are needed to assess the competence of ticks as vectors of Leishmania parasites from dog to dog.


Assuntos
Doenças do Cão/parasitologia , Leishmania infantum/isolamento & purificação , Rhipicephalus sanguineus/parasitologia , Infestações por Carrapato/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Brasil , DNA de Cinetoplasto/química , DNA de Cinetoplasto/genética , DNA de Protozoário/química , DNA de Protozoário/genética , Cães , Feminino , Itália , Masculino , Reação em Cadeia da Polimerase/métodos , Glândulas Salivares/parasitologia , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Infestações por Carrapato/parasitologia
18.
Rev Bras Parasitol Vet ; 18(3): 75-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19772781

RESUMO

This article presents the results of a study on ectoparasites infesting rural dogs in Pernambuco, northeastern Brazil. Forty-one dogs from a rural community of Pernambuco were examined and 70.7% were infested by ectoparasites. The prevalence rates of infestation by ticks, fleas, and lice were 58.5, 43.9 and 22%, respectively. Of 24 dogs parasitized by ticks, 15 were exclusively infested by Rhipicephalus sanguineus (Latreille) (32 females, 66 males, 9 nymphs; prevalence, 48.8%; mean intensity, 5.4), four by Amblyomma ovale Koch (33 females, 19 males; prevalence, 22%; mean intensity, 5.8), and five were coinfested by both species. Ctenocephalides felis felis (Bouché) (25 females, 8 males; prevalence, 43.9%; mean intensity, 1.9) and Heterodoxus spiniger (Enderlein) (16 females, 11 males, 10 nymphs; prevalence, 22%; mean intensity, 4.1) were the only species of flea and louse identified. Tick infestation was more frequent than flea or lice infestations (p < 0.05). No statistical difference was found by sex and age group of the dogs studied and prevalence of infestation. Overall, 48.8% (20/41) of the dogs were infested by more than one ectoparasite species.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Ectoparasitoses/veterinária , Animais , Brasil/epidemiologia , Cães , Ectoparasitoses/epidemiologia , Feminino , Masculino , Saúde da População Rural
19.
Rev. bras. parasitol. vet ; 18(3): 75-77, July-Sept. 2009. tab
Artigo em Inglês | LILACS | ID: lil-606796

RESUMO

This article presents the results of a study on ectoparasites infesting rural dogs in Pernambuco, northeastern Brazil. Forty-one dogs from a rural community of Pernambuco were examined and 70.7 percent were infested by ectoparasites. The prevalence rates of infestation by ticks, fleas, and lice were 58.5, 43.9 and 22 percent, respectively. Of 24 dogs parasitized by ticks, 15 were exclusively infested by Rhipicephalus sanguineus (Latreille) (32 females, 66 males, 9 nymphs; prevalence, 48.8 percent; mean intensity, 5.4), four by Amblyomma ovale Koch (33 females, 19 males; prevalence, 22 percent; mean intensity, 5.8), and five were coinfested by both species. Ctenocephalides felis felis (Bouché) (25 females, 8 males; prevalence, 43.9 percent; mean intensity, 1.9) and Heterodoxus spiniger (Enderlein) (16 females, 11 males, 10 nymphs; prevalence, 22 percent; mean intensity, 4.1) were the only species of flea and louse identified. Tick infestation was more frequent than flea or lice infestations (p < 0.05). No statistical difference was found by sex and age group of the dogs studied and prevalence of infestation. Overall, 48.8 percent (20/41) of the dogs were infested by more than one ectoparasite species.


O presente artigo apresenta os resultados de um estudo sobre os ectoparasitos que infestam cães rurais em Pernambuco, Nordeste do Brasil. Quarenta e um cães de uma comunidade rural de Pernambuco foram examinados e 70,7 por cento estavam infestados por ectoparasitos. As taxas de prevalência de infestação por carrapatos, pulgas e piolhos foram 58,5, 43,9 e 22 por cento, respectivamente. Dos 24 cães parasitados por carrapatos, 15 estavam exclusivamente infestados por Rhipicephalus sanguineus (Latreille) (32 fêmeas, 66 machos, 9 ninfas; prevalência, 48,8 por cento; intensidade média, 5,4), quatro por Amblyomma ovale Koch (33 fêmeas, 19 machos; prevalência, 22 por cento; intensidade média, 5,8), e cinco estavam co-infestados por ambas as espécies. Ctenocephalides felis felis (Bouché) (25 fêmeas, 8 machos; prevalência, 43,9 por cento; intensidade média, 1,9) e Heterodoxus spiniger (Enderlein) (16 fêmeas, 11 machos, 10 ninfas; prevalência, 22 por cento; intensidade média, 4,1) foram as únicas espécies de pulga e piolho identificadas. A infestação por carrapatos foi mais frequente que as infestações por pulgas ou piolhos (p < 0.05). Não houve diferença estatística em relação ao sexo e grupo etário dos cães e a prevalência de infestação. No geral, 48,8 por cento (20/41) dos cães estavam infestados por mais de uma espécie de ectoparasito.


Assuntos
Animais , Cães , Feminino , Masculino , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Ectoparasitoses/veterinária , Brasil/epidemiologia , Ectoparasitoses/epidemiologia , Saúde da População Rural
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