Coprological studies of school children from four communities in the Northern Bolivian Altiplano were carried out in order to estimate the prevalences and intensities of Fasciola hepatica infection. Single stool specimens were collected at random from 558 school children (308 boys and 250 girls) aged 5-19 years old. Nineteen different parasite species (13 protozoan and six helminths) were detected. Of the children examined, 98.7% (96.5- 100%) presented infection with at least one parasite species. The mean prevalence of 27.6% by Fasciola hepatica (range, 5.9-38.2%) was the highest not only with respect to the helminth species found in the Northern Bolivian Altiplano but also among the fasciolosis prevalences reported in children in other parts of the world to date. Prevalences were significantly different among the communities surveyed and was significantly higher in the 9-12 years age group. There were, however, no significant differences between sexes. Among the 154 children presenting F. hepatica eggs in stools, intensities ranged from 24-5064 eggs per gram of faeces (epg), with arithmetic and geometric means of 474 and 201 epg, respectively. Significant differences in mean egg output were detected between communities, sexes and age groups. Individual fasciolosis infections coexisting with other pathogenic parasite species (Entamoeba histolytica and/or E. dispar, Giardia intestinalis, Balantidium coli, Dientamoeba fragilis, Cryptosporidium sp., Hymenolepis nana, Taenia spp., Trichuris trichiura, Ascaris lumbricoides and Enterobius vermicularis) were detected. A significant positive association with F. hepatica was only found in the case of G. intestinalis. This coprological study not only verifies the existence of high prevalences of F. hepatica among humans in the Northern Bolivian Altiplano, but also demonstrates the need to expand the Southern boundaries of this high endemic zone to include the Southeastern region of Lake Titicaca.
Nota bibliográficaFunding Information:
This work was supported by funding from the STD Programme of the Commission of the European Communities (DG XII: Science, Research and Development) (Contract No. TS3-CT94-0294), Brussels, EU, the Programme of Scientific Cooperation with Latin America, Instituto de Cooperación Iberoamericana, Agencia Española de Cooperación Internacional (I.C.I.-A.E.C.I.), Madrid, Spain and Project PDP B2/181/125 of the WHO of Geneva, Switzerland. C. Aguirre thanks the MUTIS Scholarship Programme of the Instituto de Cooperación Iberoamericana of the Agencia Española de Cooperación Internacional (ICI-AECI), Madrid for a fellowship. This research was performed in partial fulfillment of a doctoral degree by C. Aguirre at the Department of Parasitology of the University of Valencia, Spain. We would like to thank Dr J.A. Oviedo (Valencia, Spain) and Miss M. Magariño (La Paz, Bolivia) for technical assistance in the schools surveyed. The authors also acknowledge the facilities provided and the collaboration received from the following Bolivian organisms, institutions and centres, as well as their respective representatives or directors: Instituto Nacional de Laboratorios de Salud (INLASA) of La Paz, Dirección Nacional de Relaciones Internacionales and the Dirección Nacional de Epidemiologı́a of the Ministerio de Previsión Social y Salud Pública (today the Secretarı́a Nacional de Salud of the new Ministerio de Desarrollo Humano) in La Paz; Comité Regional de Zoonosis and Centro Piloto La Paz of the Unidad Sanitaria La Paz; Dirección Nacional de Producción Pecuaria and the Instituto Nacional de Biologı́a Animal of Chasquipampa-Calacoto both of the Ministerio de Asuntos Campesinos y Agropecuarios (M.A.C.A.) in La Paz; Granja de Mejoramiento Ganadero de Kallutaca related to the Programa de Fomento Lechero of the Corporación Regional de Desarrollo de La Paz (CORDEPAZ); Office of the Pan American Health Organization in La Paz; Danish NGO Danchurchaid-Bolivia in La Paz; Centro de Datos para la Conservación (de América Latina y el Caribe) in Calacoto-La Paz; and Instituto de Ecologı́a of the Facultad de Ciencias Puras y Naturales of the Universidad Mayor de San Andrés (UMSA) in Calacoto-La Paz.