Potential for transmission of schistosomiasis in Kayonza district

Introduction: Schistosomiasis, also known as bilharzia or snail fever, is a tropical parasitic disease caused by a trematode platyhelminthes called Schistosoma sp. Schistosoma species are transmitted by cercariae penetrating the skin when a person is bathing, washing clothes, fishing or engaged in agricultural activities; involving contact with fresh water that has fecal or urinary contamination, and contains the parasites’ snail host. The present study aimed to survey freshwater snails in Kayonza District (Rwanda) especially Lake Muhazi and surrounding water bodies, stream and swamps to assess the potential for transmission of two species of Schistosoma: S. mansoni and S. haematobium . Methods: Six sites were selected to assess the potential for transmission of schistosomiasis. The intermediate hosts of schistosomes, namely the snails Biomphalaria , Bulinus sp. and Lymnaea sp., were collected and brought to the laboratory and investigated to see if trematode cercaria responsible for the disease were present. Results: Snails dissected were not only infected with trematode cercaria but also with annelids and flatworms (Platyhelminths). Cercaria found therein were of two types: furcocercous, probably responsible for schistosomiasis; and gymnocephalous cercaria for fasciolasis: an infection of cattle, goats and sheep. Conclusion: Biomphalaria sp were the major hosts for schistosome cercaria, and most snails collected of this species were infected. Moreover, they were found in large number from all sites. Lymnaea sp, hosts snails for Fasciola cercaria , were also found in a considerable number compared to the low number of Bulinus sp in the region. District and national authorities may wish to further investigate this infestation and identify potential interventions to disrupt the disease transmission.Introduction: La schistosomiase également connue sous le nom de bilharziose est une maladie parasitaire tropicale causée par des plathelminthes trématodes appelés schistosomes. Les Schistosomes sont transmises par des cercaires pénétrant la peau quand une personne se baigne, lave des vêtements, pêche ou pendant des activités agricoles en contact avec l’eau douce contaminée par des matières fécales ou urinaires, et contenant les mollusques hôtes intermédiaires des parasites. La présente étude visait à examiner les mollusques d’eau douce dans le district de Kayonza (Rwanda) particulièrement le lac Muhazi et les eaux environnantes: les ruisseaux et les marais; pour évaluer le potentiel de la transmission de deux espèces de schistosome: Schistosoma mansoni et Schistosoma haematobium . Méthodes: Six endroits ont été choisis pour évaluer le potentiel pour la transmission de la schistosomiase. Des mollusques hôtes intermédiaires des schistosomes, à savoir les espèces de Biomphalaria , Bulinus sp. et Lymnaea sp. ont été collectés, amenés au laboratoire et étudiés pour voir si les cercaires de trématodes responsables de la maladie étaient présentes. Résultats: Des mollusques disséqués ont été atteints par les cercaires de trématodes mais également par des annélides et des vers plats (Plathelminthes). Les Cercaires trouvées là-dedans étaient de deux types: furcocercaires, probablement responsable de la schistosomiase et cercaires gymnocéphales probablement responsables du fasciolose: une infection du bétail, des chèvres et des moutons. Conclusion: Les espèces Biomphalaria étaient les principaux hôtes des cercaires des schistosomes, les plus infectés parmi les espèces des mollusques collectés. Ces espèces de Biomphalaria ont été trouvées en grand nombre dans tous les sites. Les espèces de Lymnaea, mollusques hôtes intermédiaires pour les cercaires de Fasciola cercaria , ont été également trouvés en nombre considérable comparé à un nombre peu élevé des espèces Bulinus dans la région. Les autorités de district et ainsi que nationales devraient étudier davantage cette infestation et identifier les interventions potentielles pour interrompre sa transmission

Polyparasite Helminth infections and their association to anaemia and undernutrition in Northern Rwanda

Abstract Background Intestinal schistosomiasis and soil-transmitted helminth (STH) infections constitute major public health problems in many parts of sub-Saharan Africa. In this study we examined the functional significance of such polyparasite infections in anemia and undernutrition in Rwandan individuals. Methods Three polyparasite infection profiles were defined, in addition to a reference profile that consisted of either no infections or low-intensity infection with only one of the focal parasite species. Logistic regression models were applied to data of 1,605 individuals from 6 schools in 2 districts of the Northern Province before chemotherapeutic treatment in order to correctly identify individuals who were at higher odds of being anaemic and/or undernourished. Findings Stunted relative to nonstunted, and males compared to females, were found to be at higher odds of being anaemic independently of polyparasite infection profile. The odds of being wasted were 2-fold greater for children with concurrent infection of at least 2 parasites at M+ intensity compared to those children with the reference profile. Males compared to females and anaemic compared to nonanaemic children were significantly more likely to be stunted. None of the three polyparasite infection profiles were found to have significant effects on stunting. Conclusion The present data suggest that the levels of polyparasitism, and infection intensities in the Rwandan individuals examined here may be lower as compared to other recent similar epidemiological studies in different regions across sub-Saharan Africa. Neither the odds of anaemia nor the odds of stunting were found to be significantly different in the three-polyparasite infection profiles. However, the odds of wasting were higher in those children with at least two parasites at M+ intensity compared to those children with the reference profile. Nevertheless, despite the low morbidity levels indicated in the population under study here, we recommend sustainable efforts for the deworming of affected populations to be continued in order to support the economic development of the country

A Recent Update Of Schistomiasis Mansoni Endemicity Around Lake Rweru

Background: Schistosomiasis remains a global public health challenge with an estimated 200 million cases reported each year. In Rwanda, the prevalence of schistosomiasis was recently examined by a countrywide mapping conducted by the Neglected Tropical Disease (NTD) Control Programme of the Rwandan Ministry of Health in partnership with The Access Project. Unfortunately, that study failed to consider one area of endemicity -- Lake Rweru, located in Bugesera District, Eastern Province, Rwanda. This screening aimed to evaluate Lake Rweru and its environs in order to determine next steps for disease control. Methods: The lake’s shore inhabitants, including children and adults, were invited to be screened for intestinal schistosomiasis. The stool examination was performed by Kato-Katz technique. Results: A total of 270 children and adults were parasitologically screened. Fifty seven (57) cases of schistosomiasis mansoni were confirmed (21.1%). The highest proportion of S. mansoni infection was observed at Mazane Island (30.1% of 93 island inhabitants screened). Conclusion: The present results confirm that Lake Rweru is a significant source of S. mansoni infection in the country. We recommend further future investigations in order to know the true disease prevalence. While the mass de-worming campaign against schistosomiasis in addition to soil-transmitted helminthiasis is being regularly conducted by the Ministry of Health in all endemic areas, the population surrounding Lake Rweru should receive special attention.Contexte: La schistosomiase demeure un problème important de santé publique globalement avec environ 200 millions de cas rapportés chaque année. Au Rwanda, la situation de la schistosomiase a été récemment mise à jour par une cartographie nationale conduite par le Programme de Contrôle des Maladies Tropicales Négligées (MTN) du Ministère de la Santé en collaboration avec The Access Project. Cependant, le lac Rweru situé dans le District de Bugesera, Province de l’Est, Rwanda, a été incorrectement manqué parmi les foyers les plus endémiques. L’investigation visait à confirmer le foyer afin de déterminer de prochaines étapes pour le contrôle de l’infestation à Schistosoma mansoni. Méthodes: La population habitant aux alentours du lac Rweru comprenant des enfants et des adultes a été invitée à fournir leurs échantillons de selles en vue d’être examinés pour la schistosomiase intestinale. L’examen de selles a été réalisé par la technique de Kato-Katz. Résultats: Un total de 270 individus (des enfants et des adultes) ont été examinés parasitologiquement. Cinquante-sept (57) cas de schistosomiase mansoni ont été confirmés (21.1%). On a observé la proportion la plus élevée de l’infection à S. mansoni à l’île de Mazane (30.1% de 93 habitants insulaires testés). Conclusion: Les résultats actuels confirment que le lac Rweru est une source importante de S. mansoni dans le pays. Nous recommandons des enquêtes postérieures afin de connaître la vraie prévalence de la maladie dans cette zone. Pendant que la campagne de déparasitage de masse contre la schistosomiase en plus des géo-helminthiases est régulièrement organisée par le Ministère de la Santé dans toutes les zones endémiques, la population environnant le lac Rweru devrait recevoir une attention particulière

Regulation of Dietary Protein Solubility Improves Ruminal Nitrogen Metabolism In Vitro: Role of Bacteria–Protozoa Interactions

Precision dietary interventions (e.g., altering proportions of dietary protein fractions) has significant implications for the efficiency of nutrient use in ruminants, as well as lowering their environmental footprint, specifically nitrogen (N) emissions. Soluble protein (SP) is defined as the protein fraction that is rapidly degraded in the rumen (e.g., non-protein N and true protein), and our previous study found that regulating SP levels could improve N efficiency in Hu sheep. Thus, the present study was conducted to explore in vitro how protein fractions with different SP levels modulate the rumen microbial community and its association with N metabolism. Four dietary treatments with different SP proportions and similar crude protein (CP) content (~14%) were formulated (% of CP): 20 (S20), 30 (S30), 40 (S40) and 50 (S50). Results showed that NH3-N content increased with increasing SP levels at 4, 12 and 24 h; TVFA, acetate, propionate and valerate were higher in S30 and S40 (p < 0.05) and had quadratic effects (p < 0.05). Moreover, dry matter digestibility (DMD) and N digestibility (ND) were all decreased with S20 and S50 (p < 0.05). The S30 and S40 treatments increased the abundance of Bacteroidetes and Prevotella (Prevotella_ruminicola) but decreased the abundance of Firmicutes and Proteobacteria (p < 0.05). Bacterial pathways related to amino acid and fatty acid metabolism also were enriched with S30 and S40. The abundance of Entodinium was increased with S30 and S40 and had a positive correlation with Prevotella, and these two genera also played an important role in N metabolism and VFA synthesis of this study. In conclusion, bacterial and protozoal communities were altered by the level of SP (% of CP), with higher SP levels (~50% of CP) increasing the microbial diversity but being detrimental to rumen N metabolism