RESUMO
Despite the broad distribution of M. ozzardi in Latin America and the Caribbean, there is still very little DNA sequence data available to study this neglected parasite's epidemiology. Mitochondrial DNA (mtDNA) sequences, especially the cytochrome oxidase (CO1) gene's barcoding region, have been targeted successfully for filarial diagnostics and for epidemiological, ecological and evolutionary studies. MtDNA-based studies can, however, be compromised by unrecognised mitochondrial pseudogenes, such as Numts. Here, we have used shot-gun Illumina-HiSeq sequencing to recover the first complete Mansonella genus mitogenome and to identify several mitochondrial-origin pseudogenes. Mitogenome phylogenetic analysis placed M. ozzardi in the Onchocercidae "ONC5" clade and suggested that Mansonella parasites are more closely related to Wuchereria and Brugia genera parasites than they are to Loa genus parasites. DNA sequence alignments, BLAST searches and conceptual translations have been used to compliment phylogenetic analysis showing that M. ozzardi from the Amazon and Caribbean regions are near-identical and that previously reported Peruvian M. ozzardi CO1 reference sequences are probably of pseudogene origin. In addition to adding a much-needed resource to the Mansonella genus's molecular tool-kit and providing evidence that some M. ozzardi CO1 sequence deposits are pseudogenes, our results suggest that all Neotropical M. ozzardi parasites are closely related.
Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Genoma Mitocondrial , Mansonella/classificação , Mansonella/genética , Mansonelose/parasitologia , Pseudogenes , Animais , Genômica/métodos , Humanos , Filogenia , RNA Ribossômico/genética , RNA Ribossômico 5S/genéticaRESUMO
INTRODUCTION Mansonella ozzardi is a widely distributed filaria worm in the Amazon region. This study aimed to determine the prevalence of M. ozzardi infection in riverine communities of Lábrea municipality, Amazonas State, Brazil. METHODS A diagnostic blood filtration method in a polycarbonate membrane was used. RESULTS M. ozzardi was found in 50.3% of the sample, with the highest prevalence in farmers/fishermen (69.4%; χ 2 = -19.14, p<0.001). The prevalence was higher in longer-term residents (≥11 years; 60.2%). CONCLUSIONS M. ozzardi infection rates are high near the Purus River, much greater than those previously reported based on diagnosis using thick blood smears.
Assuntos
Mansonella/isolamento & purificação , Mansonelose/diagnóstico , Mansonelose/epidemiologia , Adolescente , Adulto , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mansonella/classificação , Filtros Microporos , Pessoa de Meia-Idade , Cimento de Policarboxilato , Prevalência , População Rural , Adulto JovemRESUMO
INTRODUCTION: This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil. METHODS: The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears. RESULTS: The M. ozzardi prevalence rate was 6.3% (19/300). Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%. CONCLUSIONS: Tefé is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions.
Assuntos
Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mansonella/classificação , Mansonelose/diagnóstico , Pessoa de Meia-Idade , Prevalência , Rios , População Rural , Adulto JovemRESUMO
Introduction: This study assessed the prevalence of Mansonella ozzardi in riverine communities of the Tefé River, Amazonas, Brazil. Methods: The prevalence of M. ozzardi was estimated by microscopic examination of thick blood smears. Results: The M. ozzardi prevalence rate was 6.3% (19/300). Filarial infection was found in 8 of the 11 communities surveyed, with prevalence rates varying from 2.5% to 22.2%. Conclusions: Tefé is a region of oil and natural gas exploration, in which there is a high turnover of workers. Migration patterns may facilitate the dissemination of mansonelliasis to other regions. .
Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Brasil/epidemiologia , Mansonella/classificação , Mansonelose/diagnóstico , Prevalência , Rios , População RuralRESUMO
DNA sequence comparisons are useful for characterizing proposed new parasite species or strains. Microfilariae with an atypical arrangement of nuclei behind the cephalic space have been recently described in human blood samples from the Amazon region of Peru. Three blood specimens containing atypical microfilariae were genetically characterized using three DNA markers (5S ribosomal DNA, 12S ribosomal DNA, and cytochrome oxidase I). All atypical microfilariae were clustered into the Mansonella group and indistinguishable from M. ozzardi based on these DNA markers.
Assuntos
DNA de Helmintos/isolamento & purificação , Mansonella/genética , Mansonelose/parasitologia , Microfilárias/genética , Animais , DNA de Helmintos/genética , Humanos , Mansonella/classificação , Mansonella/isolamento & purificação , Mansonelose/sangue , Microfilárias/classificação , Microfilárias/isolamento & purificação , Peru , Filogenia , Análise de Sequência de DNARESUMO
We present filaria-nested polymerase chain reaction (PCR), which is based on amplification of first internal transcribed spacer rDNA to distinguish three parasitic filarial species (Onchocerca volvulus, Mansonella ozzardi and Mansonella perstans) that can be found in the Amazon Region. Nested PCR-based identifications yielded the same results as those utilizing morphological characters. Nested PCR is highly sensitive and specific and it detects low-level infections in both humans and vectors. No cross-amplifications were observed with various other blood parasites and no false-positive results were obtained with the nested PCR. The method works efficiently with whole-blood, blood-spot and skin biopsy samples. Our method may thus be suitable for assessing the efficacy of filaria control programmes in Amazonia by recording parasite infections in both the human host and the vector. By specifically differentiating the major sympatric species of filaria, this technique could also enhance epidemiological research in the region.
Assuntos
DNA de Protozoário/análise , DNA Ribossômico/análise , Mansonella/genética , Onchocerca volvulus/genética , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/análise , Animais , Brasil , Humanos , Mansonella/classificação , Mansonella/isolamento & purificação , Onchocerca volvulus/isolamento & purificação , Reprodutibilidade dos Testes , Especificidade da EspécieRESUMO
An unidentified microfilaria sharing characteristics with Mansonella ozzardi and Onchocerca volvulus was detected in blood samples from seven human volunteers, inhabitants of a community in the border of Amazonas and Acre State. They were detected during epidemiological studies carried out in some communities along Antimary, Acre, and Purus Rivers in the Brazilian Amazon. The most striking difference was presented in the shape of the cephalic space from this microfilaria which was different from those of M. ozzardi and with similarities to O. volvulus in this region, but no remarkable differences were observed at the caudal region. More accurate studies are being carried out in order to provide additional data and supporting evidences before establishment of a new species can be done.
Assuntos
Sangue/parasitologia , Filariose/epidemiologia , Microfilárias/classificação , Animais , Brasil/epidemiologia , Filariose/parasitologia , Interações Hospedeiro-Parasita , Humanos , Mansonella/classificação , Microfilárias/anatomia & histologia , Microfilárias/isolamento & purificação , Microscopia , Onchocerca volvulus/classificação , Rios , Especificidade da EspécieRESUMO
The distribution of mansonelliases and their relation to various quantitative criteria were determined through the study of 1,057 subjects in 17 localities in ten regions of Amazonas State and Bolívar State. The total prevalence among the blood samples, determined through the Knott technique, was 18.54%. 11.26% were parasited by Mansonella perstans, 9.93% by Mansonella ozzardi, and 2.63% by both species. The average of microfilaremia was 48.19 mf/mL of blood in M. perstans and 13.79 mf/mL in M. ozzardi. In the regions studied, M. ozzardi has a wider area of distribution than M. perstans. Prevalence, average number of parasites per host, and the infection index have a positive and statistically significant correlation with the total annual precipitation mean for each region for M. perstans; in the case of M. ozzardi the quantitative parameters are positively correlated with the altitude of each region, this correlation being statistically significant. With respect to type of vegetation, M. perstans had a higher infection index in Amazonian caatinga transition in pluvial lowland forest, and M. ozzardi in semideciduous forest of the alisio type. Therefore two types of transmission, M. ozzardi-Simulium and M. perstans-Culicoides are suggested.
Assuntos
Mansonelose/epidemiologia , Animais , Humanos , Mansonella/classificação , Prevalência , Venezuela/epidemiologia , Água/parasitologiaRESUMO
Mansonella ozzardi is redescribed from adult worms collected from the subcutaneous tissues of patas monkeys (Erythrocebus patas) infected with a Haitian strain of the filaria. The worms are small and very slender; females measure about 49 mm in length by 0.15 mm in diameter and males, 26 by 0.07 mm. Haitian (Caribbean) and Colombian (Amazon) forms of the filaria are morphologically identical, as are their microfilariae. Mansonella is most closely related to Tetrapetalonema. Based on taxonomic priority the latter becomes a synonym of Mansonella. As a consequence, T. perstans and T. streptocerca of man in Africa are designated as M. perstans (Manson, 1891) n. comb. and M. streptocerca (Macfie and Corson, 1922) n. comb. Further, M. ozzardi is most closely related to the species M. llewellyni (Price, 1962) n. comb., a parasite of the raccoon, and M. interstitium (Price, 1962) n. comb. found in squirrels, both in North America.
Assuntos
Cercopithecidae/parasitologia , Erythrocebus patas/parasitologia , Mansonella/classificação , Animais , Colômbia , Feminino , Haiti , Humanos , Masculino , Mansonella/anatomia & histologia , Mansonelose/parasitologia , Microfilárias/anatomia & histologiaRESUMO
Despues de una revision de las publicaciones argentinas sobre MANSONELLA OZZARDI se informan los resultados preliminares de una encuesta en busca de microfilarias de este parasito. Se examinaron 336 varones entre 18 y 24 anos de edad incorporados al Servicio Militar de la Provincia de Salta, Republica Argentina (casi 0.6% del total de los varones en ese grupo etario en la provincia). Se examino un mililitro de sangre concentrada segun el metodo de Knott. Aunque la tercera parte de ellos provenia de la zona oriental de la provincia donde se habian descrito areas endemicas, no se observo infeccion en ningun individuo. Los resultados negativos quizas se deben al pequeno numero de personas examinadas provenientes de regiones de endemicidad o a que se interrumpio la transmision de M.OZZARDI. Se continuara la busqueda de la "microfilaria tucumana" en zonas especificas de Salta, Jujuy y Tucuman y en hogares de ancianos en la ciudad de Salta