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Background This study aimed to compare the prevalence of intestinal parasite infestations (IPIs) in stunted children, compared to control children, in Ankasina and Andranomanalina Isotry (two disadvantaged neighborhoods of Antananarivo, Madagascar), to characterize associated risk factors and to compare IPI detection by real-time PCR and standard microscopy techniques. Methodology/Principal findings Fecal samples were collected from a total of 410 children (171 stunted and 239 control) aged 2–5 years. A single stool sample per subject was examined by simple merthiolate-iodine-formaldehyde (MIF), Kato-Katz smear and real-time PCR techniques. A total of 96.3% of the children were infested with at least one intestinal parasite. The most prevalent parasites were Giardia intestinalis (79.5%), Ascaris lumbricoides (68.3%) and Trichuris trichiura (68.0%). For all parasites studied, real-time PCR showed higher detection rates compared to microscopy (G. intestinalis [77.6% (n = 318) versus 20.9% (n = 86)], Entamoeba histolytica [15.8% (n = 65) versus 1.9% (n = 8)] and A. lumbricoides [64.1% (n = 263) versus 50.7% (n = 208)]). Among the different variables assessed in the study, age of 4 to 5 years (AOR = 4.61; 95% CI, (1.35–15.77)) and primary and secondary educational level of the mother (AOR = 12.59; 95% CI, (2.76–57.47); AOR = 9.17; 95% CI, (2.12–39.71), respectively) were significantly associated with IPIs. Children drinking untreated water was associated with infestation with G. intestinalis (AOR = 1.85; 95% CI, (1.1–3.09)) and E. histolytica (AOR = 1.9; 95% CI, (1.07–3.38)). E. histolytica was also associated with moderately stunted children (AOR = 0.37; 95% CI, 0.2–0.71). Similarly, children aged between 4 and 5 years (AOR = 3.2; 95% CI (2.04–5.01)) and living on noncemented soil types (AOR = 1.85; 95% CI, (1.18–2.09)) were associated with T. trichiura infestation. Conclusions/Significance The prevalence of IPIs is substantial in the studied areas in both stunted and control children, despite the large-scale drug administration of antiparasitic drugs in the country. This high prevalence of IPIs warrants further investigation. Improved health education, environmental sanitation and quality of water sources should be provided., Author summary In populations living in adverse conditions due to poverty, a wide variety of intestinal parasite infestations can be observed. These infestations are usually diagnosed by stool microscopy but can be easily overlooked if the procedures used are inaccurate or performed in a suboptimal way. In the present study, we investigated the prevalence of intestinal parasite infestations in stunted and control children aged from 2 to 5 years living in two disadvantaged neighborhoods of Antananarivo Madagascar. We also assessed risk factors for infestations and the diagnostic performance of microscopic techniques and real-time PCR for the detection of parasites. Almost all individuals were found to be infested with at least one parasitic species. Children aged between 4 and 5 years and mothers with low educational levels were found to be associated with infestation. Similarly, children drinking untreated water were associated with G. intestinalis and E. histolytica infestation. This latter species was also associated with moderately stunted children. Children between 4 and 5 years old and with no cemented soil type were associated with T. trichiura infestation. The high prevalence of intestinal parasite infestations among the study participants requires the improvement of health education, environmental sanitation and quality of water sources.

International audience; Pterygodermatites (Mesopectines) niameyensis n. sp. is described from Mastomys natalensis in Niamey/Niger (West Africa). It differs from other species of same subgenus by the morphology of the head, which presents 4 simple cephalic papillae and nearly axial oral opening, a number of caudal papillae, precloacal cuticular formations, and the spicule length/body length ratio. Scanning electron microscopy shows the presence of 2 pairs of lateral sensory structures for male worms.

International audience; Spermiogenesis and ultrastructure of spermatozoon of Nicolla wisniewskii (Digenea, Opecoelidae), an intestinal parasite of Salmo trutta, were studied by electron microscopy. Spermiogenesis follows the general pattern found in the Digenea. It begins with the formation of a differentiation zone, including striated rootlets associated with 2 centrioles and an intercentriolar body. The flagella undergo a rotation of greater than 90 degrees. Then, their fusion with the median cytoplasmic process is proximodistal and asynchronous. A peculiarity was observed before the fusion of flagella, i.e., the attachment zones joined as 2 pairs by an electron-dense bridge. The mature spermatozoon is characterized by 2 axonemes, cortical microtubules, a nucleus, 2 mitochondria, external ornamentation, and spinelike bodies. At the posterior end of flagella, the spermatozoon is also characterized by the presence of a central element of the axoneme and without the 9 microtubule doublets. These results were compared with those of the other digeneans and, in particular, with other species of Opecoelidae. It appears that the number of cortical microtubules and their localization in the spermatozoon may be an interesting feature of their phylogeny.

International audience; The mature Raillietina (Raillietina) baeri spermatozoon exhibits an apical cone of electron-dense material about 2.5 microm long and 0.5 microm wide and two helicoidal crest-like bodies roughly 100-125 nm thick. The latter are of different lengths, spiralized and stand in an angle of about 50 degrees with the spermatozoon axis. The axoneme is of the 9 + "1" pattern and does not reach the posterior extremity of the gamete. The nucleus is an electron-dense cord coiled in a spiral around the axoneme. The cytoplasm exhibits a posterior densification and contains few small electron-dense granules in regions I, II and V of the spermatozoon. In regions III and IV, it is divided into irregular compartments by walls of electron-dense material. The cortical microtubules are spiralized and make an angle of 40-50 degrees to the spermatozoon axis. In this work, we describe, for the first time, a spermatozoon of a davaineidaean cestode parasitic of mammals. This has enabled us to show a wide apical cone, which has never been described before in a cyclophyllidean species the spermatozoon of which has two crest-like bodies.

The present work involves an ultrastructural study of the mature spermatozoon of the anoplocephalid cestode Gallegoides arfaai (Mobedi and Ghadirian, 1977) Tenora and Mas-Coma, 1978, obtained from the small intestine of naturally infected wood mice, Apodemus sylvaticus Linnaeus, 1758 (Rodentia, Muridae). The mature spermatozoon of G. arfaai is a filiform cell, tapered at both ends and lacking mitochondria. It is characterized by the presence of a 1,000-nm-long apical cone and two 140-nm-thick crest-like bodies in its anterior extremity. The axoneme, of the 9 + '1' trepaxonematan pattern, lacks a periaxonemal sheath, and disorganization occurs at the level of the nuclear region of the sperm cell. The cortical microtubules form two to four fields according to the different regions of the male gamete. They are twisted at an angle of about 35 degrees , becoming parallel towards the posterior extremity of spermatozoon. The nucleus, spiralled around the axoneme, shows an irregular shape in both longitudinal and cross-sections. Numerous electron-dense granules were observed, which transform into an electron-dense material in the posterior extremity of the cell. Moreover, we describe for the first time the total length of the anterior region of sperm containing the helical crest-like bodies. This anterior extremity measures around 15 mum and presents two helical crest-like bodies of different lengths that describe 13-14 turns around the sperm body. Our ultrastructural results on the G. arfaai spermatozoon are compared with the ultrastructural organization of the spermatozoa of other previously studied species, with particular emphasis on the anoplocephalids.

International audience; Pterygodermatites (Mesopectines) senegalensis n. sp. (Nematoda: Rictulariidae) is described from Mastomys huberti in Senegal. It differs from other species of the subgenus by the morphology of the head, which exhibits 4 simple cephalic papillae and a nearly axial buccal opening, the length of the spicules, the number of precloacal cuticular formations, and the absence of cephalic apophyses.