Schistosomiasis mansoni in an area of low transmission: I. impact of control measures Esquistossomose mansoni em área de baixa transmissão: I. impacto das medidas de controle

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Oswaldo Marçal Júnior, Rosa Maria de Jesus Patucci, Luiz Candido de Souza Dias, Luiz Koodi Hotta, Arnaldo Etzel
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 1991
• Subjects: Schistosomiasis transmission; Schistosoma mansoni; Biomphalaria tenagophila; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Toledo
• Online Access: https://doi.org/10.1590/S0036-46651991000200001; https://doaj.org/article/71afef0613654532bb2c770803dbe761

This work was undertaken in the municipality of Pedro de Toledo (São Paulo State, Brazil) in 1987, to clarify aspects related to the transmission levels of Schistosoma mansoni in a human population where the snail host is Biomphalaria tenagophila. Since 1980 a control programme has been undertaken in this municipality. Urban and rural populations (4,719 subjects) were submitted to faecal examinations (Kato-Katz method). The overall prevalence rate was 4.8% being higher in males (6.2%) and also in the rural zone (5.8%). The geometric mean of S. mansoni eggs was 35.1 eggs per gramme of faeces (epg). Approximately 80.0% of the carriers presented less than 100 epg and only 20 individuals (9.0%) eliminated more than half of total eggs. The highest index of potencial contamination (IPC) was in the age group of 5 to 20 years (57.6%). Two thirds of the investigated patients (207) were autochthonous of Pedro de Toledo. The geographical distribution of the carriers showed a clear aggregation of the autochthonous cases and a close association between human contact sites and breeding places of B. tenagophila. This study shows that schistosomiasis subjects were not randomly aggregated, the youngsters should be the main target in the prophylaxis, and the efficacy of the control programme. Este trabalho foi realizado no município de Pedro de Toledo, no Estado de São Paulo, Brasil, em 1987 para esclarecer aspectos sobre níveis de transmissão ao homem de Schistosoma mansoni, quando o hospedeiro intermediário é Biomphalaria tenagophila. Desde 1980 vem sendo desenvolvido um programa de controle neste município. Foram submetidos a exames de fezes (método de Kato-Katz) 4.719 indivíduos das zonas rural e urbana. A taxa de prevalência foi de 4,8%, sendo maior nos homens (6,2%) e também na zona rural (5,8%). Foi de 35,1% a média de ovos de S. mansoni por grama de fezes (epg). Cerca de 80,0% dos portadores apresentavam menos de 100 epg e somente 20 indivíduos (9,0%) eliminavam mais do que metade do total de ovos. Os mais altos índices ...