Michele Spinicci1, Fabio Macchioni2, David Rojo3, Herlan Gamboa4, Ana Liz Villagrán5, Yolanda Vallejos6, Marianne Strohmeyer1, Mimmo Roselli1, Simona Gabrielli7, Gabriella Cancrini7, Joaquín Monasterio8, Paul Castellanos9, Grover Adolfo Paredes10, Sdenka Maury11, Adolfo Zárate11, Rodolfo Rocabado12, Piero Olliaro13, Antonio Montresor14, Alessandro Bartoloni1. 1. Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Florence, Italy. 2. Dipartimento di Scienze Veterinarie, Università degli Studi di Pisa, Pisa, Italy. 3. Escuela de Salud del Chaco Tekove Katu, Gutierrez, Bolivia. 4. Facultad Integral del Chaco, Universidad Autónoma Gabriel René Moreno, Camiri, Bolivia. 5. Hospital Básico de Villa Montes, Villa Montes, Bolivia. 6. Hospital Municipal de Camiri, Camiri, Bolivia. 7. Dipartimento di Sanità Pubblica e Malattie Infettive, Università di Roma Sapienza, Rome, Italy. 8. Servicio Departamental de Salud de Santa Cruz, Santa Cruz, Bolivia. 9. Servicio Departamental de Salud de Tarija, Tarija, Bolivia. 10. Programa Nacional de Zoonosis, Ministerio de Salud, La Paz, Bolivia. 11. Unidad de Epidemiologia, Ministerio de Salud, La Paz, Bolivia. 12. Servicios Generales de Salud, Ministerio de Salud, La Paz, Bolivia. 13. Special Programme for Research and Training in Tropical Diseases (TDR), WHO, Geneva, Switzerland. 14. Department of Control of Neglected Tropical Diseases, WHO, Geneva, Switzerland.
Abstract
OBJECTIVE: Preventive chemotherapy is the WHO-recommended control method for soil-transmitted helminthiases. In the Bolivian Chaco, 6-monthly single-dose mebendazole delivery to school-age children achieved a dramatic decrease in soil-transmitted helminthiases prevalence between 1987 and 2013. Consequently, in September 2016, preventive chemotherapy delivery was interrupted in nine rural communities. In compliance with WHO recommendations, we intensified surveillance to monitor soil-transmitted helminthiases prevalence and detect potential changes that would require interventions. METHODS: We conducted two cross-sectional parasitology surveys 12 months apart (September 2016-2017) among school-age children living in the communities where preventive chemotherapy delivery had been halted. Study design, methods of sampling and sample analysis technique (direct microscopy, Kato-Katz technique) followed WHO recommendations, aiming to obtain data representative of the Bolivian Chaco ecological zone. RESULTS: We collected 426 samples in 2016 and 520 in 2017. Soil-transmitted helminthiasis prevalence was unremarkable: 0.7% (95% CI 0-1.5%) in 2016 and 0.8% (0-1.5%) in 2017. Conversely, the prevalence of tapeworms (13% in 2016, 12% in 2017) and intestinal protozoan infections (81% in 2016 and 75% in 2017) continued to be high. CONCLUSIONS: Our findings support the role of preventive chemotherapy in reducing soil-transmitted helminthiases transmission, as otherwise poor hygienic and health conditions persist in the Bolivian Chaco. A national survey, involving areas from all the ecological zones of Bolivia, is now warranted.
OBJECTIVE: Preventive chemotherapy is the WHO-recommended control method for soil-transmitted helminthiases. In the Bolivian Chaco, 6-monthly single-dose mebendazole delivery to school-age children achieved a dramatic decrease in soil-transmitted helminthiases prevalence between 1987 and 2013. Consequently, in September 2016, preventive chemotherapy delivery was interrupted in nine rural communities. In compliance with WHO recommendations, we intensified surveillance to monitor soil-transmitted helminthiases prevalence and detect potential changes that would require interventions. METHODS: We conducted two cross-sectional parasitology surveys 12 months apart (September 2016-2017) among school-age children living in the communities where preventive chemotherapy delivery had been halted. Study design, methods of sampling and sample analysis technique (direct microscopy, Kato-Katz technique) followed WHO recommendations, aiming to obtain data representative of the Bolivian Chaco ecological zone. RESULTS: We collected 426 samples in 2016 and 520 in 2017. Soil-transmitted helminthiasis prevalence was unremarkable: 0.7% (95% CI 0-1.5%) in 2016 and 0.8% (0-1.5%) in 2017. Conversely, the prevalence of tapeworms (13% in 2016, 12% in 2017) and intestinal protozoan infections (81% in 2016 and 75% in 2017) continued to be high. CONCLUSIONS: Our findings support the role of preventive chemotherapy in reducing soil-transmitted helminthiases transmission, as otherwise poor hygienic and health conditions persist in the Bolivian Chaco. A national survey, involving areas from all the ecological zones of Bolivia, is now warranted.
Authors: Antonio Montresor; Natacha À Porta; Marco Albonico; Albis Francesco Gabrielli; Dina Jankovic; Christopher Fitzpatrick; Jozef Vercruysse; Bruno Levecke Journal: Trans R Soc Trop Med Hyg Date: 2014-11-16 Impact factor: 2.184
Authors: Frédérique Chammartin; Ronaldo G C Scholte; John B Malone; Mara E Bavia; Prixia Nieto; Jürg Utzinger; Penelope Vounatsou Journal: Parasit Vectors Date: 2013-05-25 Impact factor: 3.876