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2.
Parasit Vectors ; 17(1): 258, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872227

RESUMEN

BACKGROUND: Dirofilaria immitis, commonly known as heartworm (HW), is a parasitic nematode transmitted by various mosquito species, leading to heartworm disease (HWD) in dogs. Diagnosis of HW typically involves antigen or microfilariae detection, or visualization of adult worms through imaging or post mortem examination. Polymerase chain reaction (PCR) and micro RNA (miRNA) detection have been explored for HW diagnosis. METHODS: Three dogs, previously experimentally infected with HW, underwent blood sampling every 4 weeks for 7 months. Samples were assessed for antigen presence after heat treatment, PCR amplification, and microfilaria examination using Giemsa-stained thick smears. Additionally, whole blood aliquots underwent miRNA deep sequencing and bioinformatic analysis. RESULTS: Heartworm antigen was detectable after heat treatment at 20 weeks post-inoculation and via PCR at 24 weeks, with microfilariae observed in peripheral blood smears at 28 weeks. However, deep miRNA sequencing revealed that the miRNA candidate sequences are not consistently expressed before 28 weeks of infection. CONCLUSIONS: While ancillary molecular methods such as PCR and miRNA sequencing may be less effective than antigen detection for detecting immature larval stages in an early stage of infection, our experimental findings demonstrate that circulating miRNAs can still be detected in 28 weeks post-infection.


Asunto(s)
Dirofilaria immitis , Dirofilariasis , Enfermedades de los Perros , MicroARNs , Animales , Dirofilaria immitis/genética , Dirofilaria immitis/aislamiento & purificación , Perros , Dirofilariasis/diagnóstico , Dirofilariasis/parasitología , MicroARNs/sangre , MicroARNs/genética , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/diagnóstico , Antígenos Helmínticos/sangre , Antígenos Helmínticos/genética , Diagnóstico Precoz , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , Microfilarias/aislamiento & purificación , Microfilarias/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
3.
Parasitol Res ; 123(4): 191, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647713

RESUMEN

Dirofilaria immitis is a mosquito-borne nematode-causing canine heartworm disease, with adult worms localized in the pulmonary arteries and right heart. In rare cases, ectopic migration might occur, and adults and blood circulating microfilariae can be found in unusual organs or fluids (e.g., eyes, abdominal cavity, bone marrow, and urine). A 17-year-old mixed-breed female dog was presented in a private veterinary clinic in Italy for hematuria and dysuria. Physical examination showed cardiac mitral murmur with marked respiratory distress and cyanotic mucous membranes after handling. Abdominal ultrasounds revealed a non-specific chronic cystopathy, while the echocardiography showed enlargement of the right heart associated with tricuspid insufficiency and mitral regurgitation, with the presence of an adult filariae in the right ventricular chamber. Circulating microfilariae were observed in the blood smear and molecularly identified as D. immitis. Unusual microfilaruria was detected in the urine sediment. Data presented raise awareness about the occurrence of microfilariae in unusual locations, such as the bladder, suggesting the need of a thorough clinical and laboratory assessment where D. immitis is endemic.


Asunto(s)
Dirofilaria immitis , Dirofilariasis , Enfermedades de los Perros , Microfilarias , Animales , Dirofilariasis/parasitología , Dirofilariasis/diagnóstico , Perros , Dirofilaria immitis/aislamiento & purificación , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/diagnóstico , Italia , Femenino , Microfilarias/aislamiento & purificación , Orina/parasitología
4.
PLoS Negl Trop Dis ; 18(4): e0012117, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38630833

RESUMEN

Filariasis, a neglected tropical disease caused by roundworms, is a significant public health concern in many tropical countries. Microscopic examination of blood samples can detect and differentiate parasite species, but it is time consuming and requires expert microscopists, a resource that is not always available. In this context, artificial intelligence (AI) can assist in the diagnosis of this disease by automatically detecting and differentiating microfilariae. In line with the target product profile for lymphatic filariasis as defined by the World Health Organization, we developed an edge AI system running on a smartphone whose camera is aligned with the ocular of an optical microscope that detects and differentiates filarias species in real time without the internet connection. Our object detection algorithm that uses the Single-Shot Detection (SSD) MobileNet V2 detection model was developed with 115 cases, 85 cases with 1903 fields of view and 3342 labels for model training, and 30 cases with 484 fields of view and 873 labels for model validation before clinical validation, is able to detect microfilariae at 10x magnification and distinguishes four species of them at 40x magnification: Loa loa, Mansonella perstans, Wuchereria bancrofti, and Brugia malayi. We validated our augmented microscopy system in the clinical environment by replicating the diagnostic workflow encompassed examinations at 10x and 40x with the assistance of the AI models analyzing 18 samples with the AI running on a middle range smartphone. It achieved an overall precision of 94.14%, recall of 91.90% and F1 score of 93.01% for the screening algorithm and 95.46%, 97.81% and 96.62% for the species differentiation algorithm respectively. This innovative solution has the potential to support filariasis diagnosis and monitoring, particularly in resource-limited settings where access to expert technicians and laboratory equipment is scarce.


Asunto(s)
Inteligencia Artificial , Microscopía , Microscopía/métodos , Humanos , Animales , Filariasis/diagnóstico , Filariasis/parasitología , Microfilarias/aislamiento & purificación , Algoritmos , Teléfono Inteligente , Filariasis Linfática/diagnóstico , Filariasis Linfática/parasitología
5.
Acta Parasitol ; 69(2): 1115-1121, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38536612

RESUMEN

PURPOSE: Medical and veterinary filarial nematodes are transmitted by blood-feeding vectors. In dogs, these parasites are mainly represented by nematodes in which microfilariae dwell in the blood (Dirofilaria spp. and Acanthocheilonema spp.) or skin (Cercopithifilaria spp. and Onchocerca lupi). The aim of this study was to determine the prevalence of these filarial infections in dogs residing in a touristic, heavily populated location in the northeastern region of Brazil. METHODS: Blood samples (n = 245) were assessed by a modified Knott test, followed by a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for the detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis. Skin samples (n = 71) were microscopically examined and molecularly assessed through a PCR targeting the 12 S rRNA gene. RESULTS: Microfilariae and antigen of D. immitis were detected simultaneously in 15 (6.1%; 95% CI = 3.7-9.8) animals. Nine animals (3.6%; 95% CI = 1.9-6.8) were D. immitis antigen positive but microfilariae negative and nine other animals (3.6%; 95% CI = 1.9-6.8) were microfilariae positive but D. immitis antigen negative. D. immitis positive dogs were found in four different municipalities. No filarioids were detected in the skin after microscopical and molecular analyses. CONCLUSION: Data from this study demonstrate that D. immitis is the main filarial nematode infecting dogs in coastal areas in northeastern Brazil. Based on the potential risk of infection in which animals are submitted, it is essential to perform tests to detect microfilariae and D. immitis antigen. Preventive measures must be adopted by using microfilaricidal compounds and anti-feeding insecticides to prevent canine infection.


Asunto(s)
Enfermedades de los Perros , Filariasis , Animales , Perros , Brasil/epidemiología , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/epidemiología , Filariasis/veterinaria , Filariasis/epidemiología , Filariasis/parasitología , Prevalencia , Filarioidea/aislamiento & purificación , Filarioidea/genética , Microfilarias/aislamiento & purificación , Masculino , Femenino , Dirofilaria immitis/aislamiento & purificación , Dirofilaria immitis/genética , Dirofilaria immitis/inmunología , Dirofilariasis/epidemiología , Dirofilariasis/parasitología , Piel/parasitología , Ensayo de Inmunoadsorción Enzimática/veterinaria
6.
Parasitol Int ; 86: 102471, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34562631

RESUMEN

Filariasis is a common parasitic infection in India. It is rare to find neglected cases of Filariasis nowadays. We reported the presence of microfilaria species in the follicular fluid of an egg donor undergoing an ovum pick up procedure. She was a 23-year-old egg donor who underwent stimulation using the GnRH antagonist protocol. Antagonist protocol is one of the standard protocols used for controlled ovarian hyperstimulation as a part of the IVF/ICSI(in-vitro fertilization / intracytoplasmic sperm injection) procedure where GnRH antagonist (cetrorelix) is used to suppress the endogenous LH surge. Her baseline investigations were normal, with no significant history suggestive of any worm infestations. During the ovum pickup procedure, follicular fluid revealed the presence of worm-like structures suggestive of larvae of some parasites. The follicular fluid was sent to the microbiology department along with the blood sample to confirm the parasite species. The parasite was found to be the larvae of W. Bancroft. The oocytes were of poor quality and were discarded. The patient was treated with Diethylcarbamazine citrate. There are so many reports about scrotal Filariasis, but rare literature quotes ovarian Filariasis.


Asunto(s)
Filariasis/diagnóstico , Líquido Folicular/parasitología , Microfilarias/aislamiento & purificación , Enfermedades del Ovario/diagnóstico , Wuchereria bancrofti/aislamiento & purificación , Animales , Femenino , Filariasis/parasitología , Humanos , India , Microfilarias/crecimiento & desarrollo , Enfermedades del Ovario/parasitología , Wuchereria bancrofti/crecimiento & desarrollo , Adulto Joven
7.
PLoS Negl Trop Dis ; 15(10): e0009812, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34637436

RESUMEN

BACKGROUND: Molecular xenomonitoring (MX), the detection of parasite nucleic acid in the vector population, is recommended for onchocerciasis surveillance in elimination settings. However, the sensitivity of MX for detecting onchocerciasis-positive communities has not previously been evaluated. MX may have additional applications for control programmes but its utility is restricted by a limited understanding of the relationship between MX results and human prevalence. METHODS: We conducted a systematic review of studies reporting the prevalence of Onchocerca volvulus DNA in wild-caught Simulium spp. flies (MX rate) and corresponding prevalence of microfilaria (mf) in humans. We evaluated the sensitivity of MX for detecting onchocerciasis-positive communities and describe the characteristics of studies with reduced sensitivity. We conducted a linear regression to evaluate the relationship between mf prevalence and MX rate. RESULTS: We identified 15 relevant studies, with 13 studies comprising 34 study communities included in the quantitative analyses. Most communities were at advanced stages towards elimination and had no or extremely low human prevalence. MX detected positive flies in every study area with >1% mf prevalence, with the exception of one study conducted in the Venezuelan Amazonian focus. We identified a significant relationship between the two measurements, with mf prevalence accounting for half of the variation in MX rate (R2 0.50, p<0.001). CONCLUSION: MX is sensitive to communities with ongoing onchocerciasis transmission. It has potential to predict human mf prevalence, but further data is required to understand this relationship, particularly from MX surveys conducted earlier in control programmes before transmission has been interrupted.


Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Insectos Vectores/parasitología , Onchocerca volvulus/genética , Oncocercosis/diagnóstico , Simuliidae/parasitología , Animales , Pruebas Diagnósticas de Rutina/instrumentación , Pruebas Diagnósticas de Rutina/normas , Humanos , Insectos Vectores/fisiología , Microfilarias/genética , Microfilarias/aislamiento & purificación , Microfilarias/fisiología , Onchocerca volvulus/aislamiento & purificación , Onchocerca volvulus/fisiología , Oncocercosis/parasitología , Oncocercosis/transmisión , Simuliidae/fisiología
8.
Cytopathology ; 32(6): 807-812, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34273210

RESUMEN

BACKGROUND: Filariasis is a major health problem in India. Despite the high prevalence, microfilariae are rarely found in cytology smears. Most of the cases are incidentally found, solely or in association with other pathologies. AIMS AND OBJECTIVES: This study was undertaken to analyse the prevalence and cytological findings of cases of incidentally found microfilariae in cytology smears (fine needle aspiration cytology [FNAC]/exfoliative cytology) from different parts of the body. MATERIALS AND METHODS: This was a retrospective study over 3 years, in which cases of microfilariae in aspirates from swelling of different locations, body fluids, and pap smears were reviewed, and the clinicopathological data analysed. RESULTS AND ANALYSIS: Out of 11 530 cases of FNAC, 8700 cases of fluid cytology, and 9000 of conventional cervicovaginal smears, 12 cases (0.04%) of incidental findings of microfilariae were documented in cytology smears. The cases were diagnosed from lymph node (one case), hand (one case), scrotal area (one case), axilla (one case), breast (one case), subcutaneous tissue (three cases), urine (three cases), and Pap smear (one case). We found eosinophilia in one case (8.3%) of filarial lesions. We found two cases of incidental findings of microfilariae in association with malignant lesions. CONCLUSION: Cytology smear examination can play an important role in diagnosing occult filariasis in clinically unsuspected cases in association with other pathologies.


Asunto(s)
Citodiagnóstico , Filariasis , Microfilarias/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biopsia con Aguja Fina , Femenino , Filariasis/diagnóstico , Filariasis/parasitología , Filariasis/patología , Humanos , India , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
9.
Parasitol Int ; 84: 102404, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34129934

RESUMEN

Cameline filarosis is an important parasitic disease having an economic impact on the camel industry around the world. However, there has been no study on filarosis in Bactrian camels of Mongolia. Therefore, the aim of the present study was to detect and identify microfilariae of Deraiophoronema evansi (D. evansi) in Bactrian camels from three provinces, located in southern and southwestern Mongolia. Blood samples were obtained from 400 healthy two-humped camels of different ages and both sexes. All blood samples were analysed using a variety of diagnostic techniques. Microfilariae were detected in 30 Bactrian camels (7.5%) by the Knott technique, while 13 Bactrian camels (3.3%) tested positive in a direct smear test. D. evansi was detected in 18 Bactrian camels (4.5%) by PCR assay. Prevalence was shown to be high among Bactrian camels in the age group up to 5 years, while the lowest positive results were obtained for Bactrian camels in the 5-10-year age group and the over 10-year age group. To confirm the morphological identification, D. evansi-COI gene sequences were subjected to phylogenetic analyses. The D. evansi-COI gene sequences from Mongolian two-humped camels were identical to sequences from Iranian one-humped camels and were clustered together with these sequences in the phylogeny. This is the first report of molecular detection and identification of microfilariae of D. evansi in Bactrian camels of Mongolia.


Asunto(s)
Camelus , Infecciones por Dipetalonema/veterinaria , Dipetalonema/aislamiento & purificación , Animales , Dipetalonema/genética , Infecciones por Dipetalonema/diagnóstico , Infecciones por Dipetalonema/epidemiología , Infecciones por Dipetalonema/parasitología , Complejo IV de Transporte de Electrones/análisis , Femenino , Proteínas del Helminto/análisis , Masculino , Microfilarias/aislamiento & purificación , Mongolia/epidemiología , Prevalencia
10.
J Helminthol ; 95: e25, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33958012

RESUMEN

While much attention has been paid to vector-borne filariasis, diseases that threaten millions of people in tropical and subtropical countries, the literature on host-parasite associations and transmission strategies of filarial nematodes in wildlife is scarce. Here, we report the co-occurrence of chigger mites (Eutrombicula alfreddugesi) and onchocercid nematodes (Oswaldofilaria chabaudi) parasitizing the lizard Tropidurus torquatus in the State of Minas Gerais, Brazil. Examination of chiggers established, for the first time, the occurrence of microfilariae in trombiculid mites (Trombiculidae). These larvae were morphologically similar to those recovered from adult females of O. chabaudi. The current evidence suggests that chiggers do not play a role in the transmission of filarioid nematodes, but rather act as accidental or dead-end hosts. Nevertheless, considering the polyphagous nature of trombiculid mites, similar to blood-sucking insects involved in the transmission of several infectious diseases, further studies may shed light on the potential role of chiggers as vectors of filarioids.


Asunto(s)
Lagartos , Microfilarias/aislamiento & purificación , Nematodos , Trombiculidae , Animales , Brasil , Coinfección/parasitología , Coinfección/veterinaria , Femenino , Interacciones Huésped-Parásitos , Lagartos/parasitología , Nematodos/aislamiento & purificación , Trombiculidae/parasitología
11.
Parasitol Res ; 120(6): 2109-2124, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33963428

RESUMEN

Acanthocheilonema reconditum is a filarial parasite transmitted by arthropods (fleas, lice, and ticks) that infect dogs. There is minimal published data available to date on potential haematological and biochemical changes associated with this parasitic infection. Study aims were (i) provide an overview of A. reconditum in Europe, (ii) define A. reconditum prevalence and risk factors in a specific dog population (hunting) from southern Italy, and (iii) assess the frequency of haemato-biochemical abnormalities associated with infection. Blood samples collected from 3020 dogs were tested by a modified Knott's technique to count and identify microfilariae. Eighty-four dogs were infected by A. reconditum (2.78%; 95% CI 2.19-3.37%). Microfilariae ranged from 1 to 212/ml. Based on clinical examination, all but six dogs with non-specific symptoms were healthy. Haematological abnormalities included leucocytosis (n = 15), with eosinophilia (n = 14) and monocytosis (n = 13). Serum biochemical abnormalities included increased total serum proteins (n = 19), albumins (n = 7), total globulins (n = 14), ALT (n = 1), and ALP (n = 1); one dog was hypoalbuminemic, and BUN was mildly increased in 2 dogs. Risk factors included the province origin (Napoli, OR=5.4, 95%CI: 2.1-14.0; Caserta, OR=5.1, 95%CI: 2.5-10.6), hunting wild mammals (OR=2.8, 95% 95%CI: 1.6-4.8), and ectoparasite infestation (OR=1.9, 95%CI: 1.1-3.1). There was a negative correlation between microfilaraemic load and decreased albumin level (-0.37; p=0.021). Our results showed that A. reconditum circulates within the hunting dog population of southern Italy, with seemingly low pathogenic potential.


Asunto(s)
Acanthocheilonema/patogenicidad , Acantoqueilonemiasis/veterinaria , Enfermedades de los Perros/parasitología , Enfermedades Hematológicas/veterinaria , Perros de Trabajo/parasitología , Acanthocheilonema/aislamiento & purificación , Acantoqueilonemiasis/sangre , Acantoqueilonemiasis/epidemiología , Acantoqueilonemiasis/parasitología , Animales , Enfermedades de los Perros/sangre , Enfermedades de los Perros/epidemiología , Perros , Enfermedades Hematológicas/sangre , Enfermedades Hematológicas/epidemiología , Enfermedades Hematológicas/parasitología , Italia/epidemiología , Masculino , Microfilarias/aislamiento & purificación , Microfilarias/patogenicidad , Prevalencia , Factores de Riesgo
12.
Parasit Vectors ; 14(1): 227, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33926526

RESUMEN

BACKGROUND: Dirofilariosis is a vector-borne parasitosis caused by filarial nematodes of the genus Dirofilaria. In humans, who represent accidental hosts, dirofilariosis is mostly caused by Dirofilaria repens and Dirofilaria immitis. In Austria, the first reported case occurred in 1978. Since then, several (case) reports have been published. METHODS: A systematic and retrospective review of collected published cases and new, unpublished confirmed cases of human dirofilariosis occurring in Austria was performed. A nematode was extracted from the eyelid of a previously unreported case and subsequently characterized histologically and using molecular biology techniques. RESULTS: Data on a total of 39 cases of human dirofilariosis in Austria occurring between 1978 and 2020 are summarized. Over the past four decades the incidence has markedly increased, in particular after 1998. Of the 39 patients, men and women were equally affected, and the mean age was 47.1 years. The area most frequently affected was the head (38.5% of cases). Confined ocular involvement was observed in 23.1% of cases, and nematodes were isolated from the neck/trunk, extremities and the genito-inguinal area in 25.6, 15.4 and 15.4% of patients, respectively. Microfilariae were detected in two cases. Of the 39 patients, only 73.9% tested positive for anti-filarial antibodies and 56.3% for eosinophilia, despite successful isolation of a nematode; consequently, these measures did not represent reliable markers for dirofilariosis. Most patients had a travel history to countries endemic for Dirofilaria species. One patient who had not traveled abroad represented the only autochthonous case recorded to date. Dirofilaria repens was the predominant species, identified in 89.7% of cases. In the newly reported case of subcutaneous dirofilariosis, a live non-gravid Dirofilaria repens adult female of 12 cm length was isolated from the eyelid of the patient, and a video of the extraction is provided. CONCLUSIONS: The incidence of human dirofilariosis cases has increased strikingly over the last four decades in Austria. More cases can be expected in the foreseeable future due to changes in human behavior and (travel) activities as well as climate changes and the associated alterations in the availability of the natural reservoir, the vectors and the intrinsic characteristics of the parasite.


Asunto(s)
Dirofilariasis , Animales , Austria/epidemiología , Enfermedades Transmisibles/parasitología , Enfermedades Transmisibles/transmisión , Dirofilaria immitis/aislamiento & purificación , Dirofilaria repens/aislamiento & purificación , Dirofilariasis/parasitología , Dirofilariasis/transmisión , Reservorios de Enfermedades/parasitología , Párpados/parasitología , Femenino , Humanos , Incidencia , Masculino , Microfilarias/aislamiento & purificación , Estudios Retrospectivos , Enfermedades Transmitidas por Vectores/parasitología , Enfermedades Transmitidas por Vectores/transmisión
13.
PLoS Negl Trop Dis ; 15(3): e0009294, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33780481

RESUMEN

Improved treatments for lymphatic filariasis (LF) could accelerate the global elimination program for this disease. A triple drug combination of the anti-filarial drugs ivermectin, diethylcarbamazine (DEC) and albendazole (IDA) has been shown to be safe and effective for achieving sustained clearance of microfilariae (Mf) of the filarial parasite Wuchereria bancrofti from human blood. However, the triple drug combination has not been previously been evaluated for treatment of brugian filariasis, which accounts for about 10% of the global LF burden. This hospital-based clinical trial compared the safety and efficacy of IDA with that of the standard treatment (DEC plus albendazole, DA) in persons with Brugia timori infections on Sumba island, Indonesia. Fifty-five asymptomatic persons with B. timori Mf were treated with either a single oral dose of IDA (28 subjects) or with DEC plus albendazole (DA, 27 subjects). Participants were actively monitored for adverse events (AE) for two days after treatment by nurses and physicians who were masked regarding treatment assignments. Passive monitoring was performed by clinical teams that visited participant's home villages for an additional five days. Microfilaremia was assessed by membrane filtration of 1 ml night blood at baseline, at 24h and one year after treatment. IDA was more effective than DA for completely clearing Mf at 24 hours (25/28, 89% vs. 8/27, 30%, P < 0.001). By 12 months after treatment, only one of 27 IDA recipients had Mf in their blood (4%) vs. 10 of 25 (40%) in persons treated with DA (P = 0.002). Approximately 90% of participants had antibodies to recombinant filarial antigen BmR1 at baseline. Antibody prevalence decreased to approximately 30% in both treatment groups at 12 months. About 45% of persons in both treatment groups experienced AE such as fever, muscle aches, lower back, joint and abdominal pain. These were mostly mild and most common during the first two days after treatment. No participant experienced a severe or serious AE. This study showed that IDA was well-tolerated and significantly more effective for clearing B. timori Mf from the blood than DA. Larger studies should be performed to further assess the safety and efficacy of IDA as a mass drug administration regimen to eliminate brugian filariasis. Trial Registration: NCT02899936.


Asunto(s)
Albendazol/uso terapéutico , Brugia/aislamiento & purificación , Dietilcarbamazina/uso terapéutico , Filariasis Linfática/tratamiento farmacológico , Filaricidas/uso terapéutico , Ivermectina/uso terapéutico , Adolescente , Adulto , Anciano , Animales , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/efectos de los fármacos , Enfermedades Asintomáticas/terapia , Quimioterapia Combinada/efectos adversos , Femenino , Humanos , Indonesia , Masculino , Microfilarias/aislamiento & purificación , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
14.
Parasit Vectors ; 14(1): 137, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33673865

RESUMEN

BACKGROUND: Blood parasites have been the subject of much research, with numerous reports of the presence of microfilariae in the peripheral blood (circulating microfilariae) of birds belonging to many orders. Current limitations in molecular characterization methods and species identification using morphological characters of circulating microfilariae are major obstacles to improving our understanding the biology of Filarioidea species, particularly in wildlife. The aim of this study was to partially fill these gaps, with particular emphasis on morphological features of microfilariae, which are the most readily accessible stages of these pathogens. METHODS: Peripheral blood samples of 206 birds belonging to genera Acrocephalus (five species) and Sylvia (five species) were examined using the buffy coat method to process the blood samples for the presence of microfilariae. Positive birds were dissected to collect adult nematodes. Microfilariae and adult nematodes were described, and sequences of their mitochondrial cytochrome c oxidase subunit I and nuclear 28S rDNA gene fragments were obtained and used for molecular characterization and Bayesian phylogenetic inferences. RESULTS: Overall prevalence of microfilariae was 2.9%. Microfilariae were found in the blood samples from six birds (2 Acrocephalus scirpaceus and 1 each of A. arundinaceus, Sylvia atricapilla, S. borin and S. curruca), which were dissected. All parasite species observed were new. Eufilaria acrocephalusi sp. n. and Eufilaria sylviae sp. n. were present in subcutaneous, peritracheal and periesophageal connective tissues in A. scirpaceus and S. borin, respectively. Splendidofilaria bartletti sp. n. was found in finger joins of S. atricapilla. Illustrations of microfilariae and adult nematodes are shown, and morphological and phylogenetic analyses identified the DNA barcode haplotypes that are associated with these species. Phylogenetic analysis places the parasites of different genera in different closely related clades. CONCLUSIONS: Adult nematode morphological characters, which have been traditionally used in the taxonomy of Filarioidea species, have a phylogenetic value. Importantly, in our study parasites of different genera were readily distinguishable based on the morphology of their microfilariae. The link between molecular and morphology data requires more study in Filarioidea species research, particularly because this approach provides new knowledge on species identity using only readily accessible blood stages (microfilariae), thereby avoiding host dissection and thus minimizing harm to wildlife during research.


Asunto(s)
Aves/parasitología , Filariasis/veterinaria , Filarioidea/anatomía & histología , Filarioidea/genética , Microfilarias/anatomía & histología , Microfilarias/genética , Filogenia , Animales , Animales Salvajes/parasitología , Teorema de Bayes , Femenino , Filariasis/sangre , Filariasis/parasitología , Filarioidea/clasificación , Filarioidea/aislamiento & purificación , Masculino , Microfilarias/clasificación , Microfilarias/aislamiento & purificación , Análisis de Secuencia de ADN
15.
J Vet Diagn Invest ; 33(3): 572-576, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33733938

RESUMEN

Dirofilaria immitis causes life-threatening heart disease in dogs, thus screening of dog populations is important. Lens-free technology (LFT) is a low-cost imaging technique based on light diffraction that allows computerized recognition of small objects in holographic images. We evaluated an algorithm capable of recognizing microfilariae in canine whole blood using the LFT. We examined 3 groups of 10 EDTA blood specimens, from dogs with microfilaremia (group A), healthy dogs (B), and dogs with hematologic modifications other than microfilaremia (C). The LFT analyzer photographed repeated series of 5 images of all samples. The algorithm declared a sample positive if a microfilaria was detected on ≥1, ≥2, or ≥3 of the 5 images of a series. Microfilariae were detected visually in the images in 9 of 10 cases in group A; no microfilariae were seen in the images from groups B and C. Of the 30 cases, there were 14, 4, and only 3 false-positives with the 1 of 5, 2 of 5, and 3 of 5 image cutoffs, respectively. There were no false-negatives, regardless of cutoff. LFT seems useful for detecting microfilaria and could have application in clinical pathology.


Asunto(s)
Dirofilaria immitis/aislamiento & purificación , Dirofilariasis/diagnóstico , Enfermedades de los Perros/diagnóstico , Ácido Edético/sangre , Medicina Veterinaria/instrumentación , Animales , Dirofilariasis/sangre , Enfermedades de los Perros/sangre , Perros , Femenino , Masculino , Microfilarias/aislamiento & purificación
16.
PLoS Negl Trop Dis ; 15(2): e0009027, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33566799

RESUMEN

Onchocerca lupi (Spirurida: Onchocercidae) is a filarial worm parasitizing domestic carnivores and humans. Adult nematodes usually localize beneath in the sclera or in the ocular retrobulbar of infected animals, whilst microfilariae are found in the skin. Therefore, diagnosis of O. lupi is achieved by microscopic and/or molecular detection of microfilariae from skin biopsy and/or surgical removal of adults from ocular tissues of infected hosts. An urgent non-invasive diagnostic tool for the diagnosis of O. lupi in dog is mandatory. In this study, an immunoproteomic analyses was performed using a combination of immunoblotting and mass spectrometry techniques. Onchocerca lupi major antigen (Ol-MJA) and paramyosin (Ol-PARA) proteins were identified as potential biomarkers for serodiagnosis. Linear epitopes were herein scanned for both proteins using high-density peptide microarray. Sera collected from dog infected with O. lupi and healthy animal controls led to the identification of 11 immunodominant antigenic peptides (n = 7 for Ol-MJA; n = 4 for Ol-PARA). These peptides were validated using sera of dogs uniquely infected with the most important filarioids infesting dogs either zoonotic (Dirofilaria repens, Dirofilaria immitis) or not (Acanthocheilonema reconditum and Cercopithifilaria bainae). Overall, six antigenic peptides, three for Ol-MJA and for Ol-PARA, respectively, were selected as potential antigens for the serological detection of canine O. lupi infection. The molecular and proteomic dataset herein reported should provide a useful resource for studies on O. lupi toward supporting the development of new interventions (drugs, vaccines and diagnostics) against canine onchocercosis.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Onchocerca/química , Oncocercosis Ocular/diagnóstico , Oncocercosis/diagnóstico , Tropomiosina/genética , Tropomiosina/inmunología , Animales , Biomarcadores/sangre , Enfermedades de los Perros/parasitología , Perros , Femenino , Masculino , Microfilarias/genética , Microfilarias/aislamiento & purificación , Onchocerca/inmunología , Onchocerca/aislamiento & purificación , Oncocercosis/inmunología , Oncocercosis/parasitología , Oncocercosis Ocular/sangre , Oncocercosis Ocular/inmunología , Oncocercosis Ocular/parasitología , Pruebas Serológicas , Tropomiosina/sangre , Tropomiosina/aislamiento & purificación
17.
Acta Trop ; 216: 105838, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33484727

RESUMEN

Infections with the filarial nematodes Loa loa and Mansonella perstans are among the most neglected filarial infections. L. loa is endemic in 11 countries of Central and West Africa and loiasis is estimated to affect about 20 million people. M. perstans infection is widespread in more than 30 countries of sub-Saharan Africa. Due to the difficulty in diagnosing loiasis and M. perstans mansonellosis on a clinical basis, the diagnosis of infection with L. loa and M. perstans relies on laboratory techniques. Definitive diagnosis is based on the detection, identification, and quantification of circulating microfilariae (mf) by microscopy of concentrated blood. However, this is impractical for screening purposes as it requires expert laboratory personnel, considerable blood manipulation, and is time consuming, especially for the final issue of negative result reports, which are very common in the population visited outside endemic areas. The aim of the current work is the preliminary evaluation of the performance of the in-house real-time PCR described by Ta and colleagues compared to the routine microscopic approach for the screening of filarial infections in the clinical setting outside endemic areas, using samples from patients accessing the dedicated outpatient clinics for migrants and travelers of a reference centre for tropical diseases in Northern Italy.


Asunto(s)
Loiasis/diagnóstico , Mansoneliasis/diagnóstico , Microscopía/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adulto , Animales , Femenino , Humanos , Masculino , Microfilarias/aislamiento & purificación , Estudios Retrospectivos
18.
Parasitol Res ; 120(2): 739-742, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33415394

RESUMEN

Dirofilaria repens and Dirofilaria immitis are the most common filarial species affecting humans in Europe. Dirofilaria repens causes subcutaneous or ocular infection, whereas D. immitis is responsible mainly for the pulmonary form. In this report, we present the first human case of periorbital dirofilariasis in the Czech Republic. A 58-year-old woman suffered from an eyelid oedema, redness and pain in the left eye. After excising the parasite from her eyelid, all clinical symptoms disappeared. Based on the morphology and cytochrome oxidase I sequencing, the parasite was identified as D. repens. Histology revealed that the excised worm was female with absent microfilariae in uteri. With respect to the length of the incubation period and the sequence identity with a known Czech isolate, we concluded that D. repens was most likely of autochthonous origin.


Asunto(s)
Dirofilaria repens/aislamiento & purificación , Dirofilariasis/parasitología , Infecciones Parasitarias del Ojo/parasitología , Animales , Ciclooxigenasa 1/genética , República Checa , Dirofilaria repens/citología , Dirofilaria repens/genética , Dirofilariasis/patología , Infecciones Parasitarias del Ojo/patología , Femenino , Proteínas del Helminto/genética , Humanos , Microfilarias/aislamiento & purificación , Persona de Mediana Edad
19.
Parasit Vectors ; 14(1): 19, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407819

RESUMEN

BACKGROUND: The mass drug administration of ivermectin for onchocerciasis control has contributed to a significant drop in Loa loa microfilaria loads in humans that has, in turn, led to reduction of infection levels in Chrysops vectors. Accurate parasite detection is essential for assessing loiasis transmission as it provides a potential alternative or indirect strategy for addressing the problem of co-endemic loiasis and lymphatic filariasis through the Onchocerciasis Elimination Programme and it further reflects the true magnitude of the loiasis problem as excess human mortality has been reported to be associated with the disease. Although microscopy is the gold standard for detecting the infection, the sensitivity of this method is compromised when the intensity of infection is low. The loop-mediated isothermal amplification (LAMP) assay of parasite DNA is an alternative method for detecting infection which offers operational simplicity, rapidity and versatility of visual readout options. The aim of this study was to validate the Loa loa LAMP assay for the detection of infected Chrysops spp. under experimental and natural field conditions. METHODS: Two sets of 18 flies were fed on volunteers with either a low (< 10 mf/ml) or high (> 30,000mf/ml) microfilarial load. The fed flies were maintained under laboratory conditions for 14 days and then analysed using LAMP for the detection of L. loa infection. In addition, a total of 9270 flies were collected from the north-west, east, and south-west regions (SW 1 and 2) of Cameroon using sweep nets and subjected to microscopy (7841 flies) and LAMP (1291 flies plus 138 nulliparous flies) analyses. RESULTS: The LAMP assay successfully detected parasites in Chrysops fed on volunteers with both low and high microfilariaemic loads. Field validation and surveillance studies revealed LAMP-based infection rates ranging from 0.5 to 31.6%, with the lowest levels in SW 2 and the highest infection rates in SW 1. The LAMP assay detected significantly higher infection rates than microscopy in four of the five study sites. CONCLUSION: This study demonstrated the potential of LAMP as a simple surveillance tool. It was found to be more sensitive than microscopy for the detection of experimental and natural L. loa infections in Chrysops vectors.


Asunto(s)
Dípteros/parasitología , Loa/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Animales , Camerún/epidemiología , ADN de Helmintos , Reservorios de Enfermedades , Vectores de Enfermedades , Humanos , Insectos Vectores/parasitología , Loa/genética , Loiasis/diagnóstico , Loiasis/parasitología , Microfilarias/aislamiento & purificación , Microscopía , Oncocercosis/epidemiología , Carga de Parásitos
20.
Parasitol Res ; 120(1): 311-319, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33146778

RESUMEN

DEC or ivermectin (IVM) in combination with albendazole (ALB) has been the recommended strategy of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) since 2000. Despite effective population coverage (> 65%) with several rounds of MDA with DEC or combination of DEC plus ALB, microfilariae persist in few individuals and they continue to be the source of infection for transmitting LF. We report an individual's variability in response to DEC by defining the response as complete absence of microfilaria (mf) (post-treatment mf count = 0) and non-response as presence of mf (post-treatment mf count ≥ 1). We analyzed follow-up data on individual's response to treatment from two randomized clinical trials in which 46 microfilaremic individuals were treated with single-dose DEC (6 mg/kg body weight). They were classified into low, medium, and high mf density categories based on their pre-treatment mf counts. Of the 46 individuals, 65.2% have not responded throughout the 12-month post-treatment period. Application of a logistic regression model with fixed (age, gender, mf density, post-treatment time, and their interactions) and random (individual's response over time) effects indicated that treatment response is independent of age, gender, and time. The overall treatment response increases in low and decreases in high mf density categories. Furthermore, the estimates for the random coefficients model showed that there is a greater variability in response between individuals over post-treatment time. The results substantiate that individual variation in response to DEC exists which indicate the importance of studying the parasite as well as host genetic factors associated with DEC action.


Asunto(s)
Dietilcarbamazina/uso terapéutico , Filariasis Linfática/tratamiento farmacológico , Filaricidas/uso terapéutico , Wuchereria bancrofti/efectos de los fármacos , Albendazol/uso terapéutico , Animales , Femenino , Humanos , Ivermectina/uso terapéutico , Modelos Logísticos , Masculino , Microfilarias/aislamiento & purificación
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