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Donato Traversa,
Angela Di Cesare,
Riccardo P Lia,
Giuseppe Castagna,
Silvana Meloni,
Josef Heine,
Katrin Strube,
Piermarino Milillo,
Domenico Otranto, Oliver Meckes,
Roland Schaper
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ABSTRACT: Capillaria aerophila is a trichuroid nematode affecting the respiratory system of dogs, cats, wild carnivores and, occasionally, humans. Animals become infected by ingesting larvated eggs or earthworms, which act as facultative intermediate hosts. The aim of this work is to present new insights into morphological and biological features of this neglected lungworm. Typical features of C. aerophila eggs, differentiating them from those of most known trichuroid whipworms (i.e. size, asymmetry of bipolar plugs and a wall with a network of anastomosing ridges), were detected upon light and scanning electron microscopy. Eggs of C. aerophila were used for in vitro development. Light microscopy showed typical features of C. aerophila eggs: size, asymmetry of bipolar plugs and a wall with a network of anastomosing ridges. All these features were confirmed upon SEM, in that C. aerophila eggs showed an outer densely striated and net-like shell. Eggs of T. vulpis, used for a comparative analysis, were bigger than those of C. aerophila and showed a thick and smooth wall at both light and scanning electron microscopy. Eggs started to develop after 35 days from shedding and mobile larvae were observed in the eggs after two months. The results of this study provide key information on the biological cycle of C. aerophila and present key morphological characters for the identification of eggs in faeces.
Parasitology Research 08/2011; 109 Suppl 1:S97-104. · 2.15 Impact Factor
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Hermann Feldmeier,
Lars Witt,
Stefan Schwalfenberg,
Pedro M Linardi,
Ronaldo A Ribeiro,
Raphael A C Capaz,
Eric Van Marck, Oliver Meckes,
Heinz Mehlhorn,
Norbert Mencke,
Jörg Heukelbach
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ABSTRACT: Tungiasis is endemic in many countries in Latin America, the Caribbean and sub-Saharan Africa, and it is associated with severe morbidity. The pathophysiological and immunological characteristics of the ectoparasitosis are not well understood, and no effective therapy is currently available. The aim of this study was to describe the natural history of tungiasis in laboratory-raised Wistar rats. The rats were exposed in the laboratory to the parasite or were kept in a natural environment with an intense transmission of Tunga penetrans. The time course of the infestation was determined, and lesions were photographed, described clinically in detail and biopsied. Biopsies were examined histopathologically and by light and scanning electron microscopy. Based on these findings, the natural history of tungiasis in Wistar rats was described and divided in five stages. Our data show that the natural history of tungiasis in Wistar rats and humans is almost identical, except that in the animals, the basement membrane disrupts 5 days after penetration and provokes an intense infiltration of the dermis, while in humans, the basement membrane remains intact. The study indicates that the Wistar rat is an appropriate model for the study of clinical and pathological aspects of tungiasis. Using this model should enable a better understanding of the pathophysiology and immunology of the ectoparasitosis.
Parasitology Research 01/2008; 102(1):1-13. · 2.15 Impact Factor
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ABSTRACT: Tungiasis is an important health problem in poor communities in Brazil and is associated with severe morbidity, particularly in children. The causative agent, the female flea Tunga penetrans, burrows into the skin of its host, where it develops, produces eggs and eventually dies. From the beginning of the penetration to the elimination of the carcass of the ectoparasite by skin repair mechanisms, the whole process takes 4-6 weeks. The present study is based on specimens from 86 patients, for some of whom the exact time of penetration was known. Lesions were photographed, described in detail and biopsied. Biopsies were examined histologically and by means of scanning electron microscopy (SEM). Based on clinical, SEM and histological findings, the "Fortaleza classification" was elaborated. This allows the natural history of tungiasis to be divided into five stages: (1) the penetration phase, (2) the phase of beginning hypertrophy, (3) the white halo phase, (4) the involution phase and (5) residues in the host's skin. Based on morphological and functional criteria, stages 3 and 4 are divided into further substages. The proposed Fortaleza classification can be used for clinical and epidemiological purposes. It allows a more precise diagnosis, enables the assessment of chemotherapeutic approaches and helps to evaluate control measures at the community level.
Parasitology Research 07/2003; 90(2):87-99. · 2.15 Impact Factor
