ABSTRACT
The aim of this study was to analyse the infection dynamics ofAngiostrongylus cantonensisin its possible intermediate hosts over two years in an urban area in the state of Rio de Janeiro where the presence ofA. cantonensis had been previously recorded in molluscs. Four of the seven mollusc species found in the study were exotic.Bradybaena similariswas the most abundant, followed byAchatina fulica, Streptaxissp., Subulina octona, Bulimulus tenuissimus, Sarasinula linguaeformisand Leptinaria unilamellata. Only A. fulicaand B. similariswere parasitised by A. cantonensis and both presented co-infection with other helminths. The prevalence of A. cantonensisin A. fulicawas more than 50% throughout the study. There was an inverse correlation between the population size ofA. fulicaand the prevalence of A. cantonensisand abundance of the latter was negatively related to rainfall. The overall prevalence of A. cantonensisin B. similariswas 24.6%. A. fulicawas the most important intermediary host of A. cantonensisin the studied area andB. similariswas secondary in importance for A. cantonensistransmission dynamics.
Subject(s)
Animals , Angiostrongylus cantonensis/physiology , Introduced Species , Snails/parasitology , Strongylida Infections/transmission , Animal Distribution , Angiostrongylus cantonensis/pathogenicity , Brazil/epidemiology , Cities , Climate Change , Disease Vectors , Linear Models , Mollusca/classification , Mollusca/parasitology , Rain/parasitology , Snails/classification , Strongylida Infections/epidemiologyABSTRACT
Dermatite alérgica sazonal foi diagnosticada em um rebanho de 40 ovinos da raça Santa Inês no município de Jucurutú, Estado de Rio Grande do Norte. Para o estudo epidemiológico e observação dos sinais clínicos a propriedade foi visitada periodicamente entre 2007 e 2010. Os ovinos eram criados extensivamente em campo nativo cortado pelo rio Piranhas e com um açude permanente. Entre 2007 e 2009 adoeceram 13 (32,5%) ovinos de um total de 40. As lesões eram observadas durante a época da chuva e regrediam total ou parcialmente durante a seca, reaparecendo no próximo período chuvoso. Os animais que foram retirados da área se recuperaram. No final de 2009 foram eliminados os animais susceptíveis e três novos casos apareceram em 2010. A pele apresentava lesões alopécicas, crostosas, enrugadas, esbranquiçadas e com intenso prurido, localizados na região da cabeça (orelhas, ao redor dos olhos e região frontal), região dorsal do corpo e garupa. Histologicamente, a epiderme apresentou hiperqueratose, acantose, hipergranulose e moderada espongiose. Na derme havia infiltrado inflamatório, principalmente perivascular, composto por eosinófilos, macrófagos e plasmócitos. Observou-se queratose de folículos pilosos e dilatação das glândulas sudoríparas. No hemograma, os valores de todos os animais estavam dentro dos valores normais. Em abril e junho de 2010 foram realizadas capturas de insetos com armadilhas luminosas CDC, sendo 110 dípteros capturados, dos quais 43 foram identificados como Culicoides insignis Lutz. Considerando que esta espécie tem sido associada à dermatite alérgica em outras regiões conclui-se que a doença é uma dermatite alérgica sazonal associada à picada de C. insignis.
Seasonal allergic dermatitis is reported in a flock of 40 hair sheep of the Santa Inês breed, in the county of Jucurutú, State of Rio Grande do Norte, in the semiarid region of Northeastern Brazil. For the epidemiologic and clinical observations the farm was visited periodically from 2007 to 2010. The flock was raised extensively in a Paddock crossed by the Piranhas river, and had also a permanent pond. Between 2007 and 2009, 13 (32.5%) sheep out of 40 were affected. The lesions were observed during the raining season, regressed total or partially during the dry season, and reappeared in the next raining period. Sheep removed to other region recovered. At the end of 2009, all affected sheep were removed from the flock. Three new cases appeared in 2010. The skin of the affected sheep was whitish, irregularly thickened, with alopecia, crusts, and intense pruritus. Those lesions were localized more frequently in the head (ears and periocular and frontal regions) but in some animals the dorsum and croup were also affected. Histologic lesions of the epidermis were hyperkeratosis, acanthosis, hypergranulosis, and moderate spongiosis. The dermis showed infiltration by eosinophils, macrophages and plasma cells, mainly perivascular. The hair follicles showed keratosis and the sudoriparous glands were dilated. No changes were observed in the differential blood count. In April and June 2010 insects were captured by the use of CDC light trap. Forty three out of 110 dipterous captured were identified as Culicoides insignis Lutz. It is concluded that the disease is a seasonal allergic dermatitis associated with C. insignis bites.
Subject(s)
Animals , Alopecia Areata/veterinary , Ceratopogonidae/pathogenicity , Dermatitis/pathology , Sheep/immunology , Rain/parasitology , Thinness/parasitology , Pruritus/veterinaryABSTRACT
En el estudio de las enfermedades metaxénicas el conocimiento de la biología del vector permite contar con nuevas herramientas para su combate, por ello se seleccionó la población de La Rinconada del estado Lara, Venezuela (10° 00' 15'' N, 69° 57' 00' O), para realizar capturas en el área doméstica, peridoméstica y selvática de una vivienda donde se detecto un caso de leishmaniasis visceral americana. Se colocaron periódicamente 5 trampas de luz CDC, entre los meses de marzo y junio de 2003, coincidiendo la primera captura con la primera lluvia del primer período de invierno, lográndose capturar 2608 flebótomos (1422 machos y 1186 hembras) la mayoría Lutzomyia pseudolongipalpis y solo dos Lutzomyia trinidadensis, observándose que en el mes de marzo hubo mayor abundancia de machos con una relación 2: 0,9 (dos machos por cada hembra), esto indica que posiblemente las primeras lluvias después del largo período de verano estimularon una mayor eclosión pupal de machos de esta especie, situación que se normalizó a medida que se multiplicaron las lluvias.