RESUMEN
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.
Asunto(s)
Antihelmínticos/uso terapéutico , Helmintiasis/prevención & control , Mebendazol/uso terapéutico , Bolivia/epidemiología , Quimioprevención/métodos , Niño , Estudios Transversales , Femenino , Helmintiasis/epidemiología , Humanos , Masculino , Prevalencia , Evaluación de Programas y Proyectos de Salud , Población Rural/estadística & datos numéricos , Suelo/parasitologíaRESUMEN
OBJECTIVES: The prevalence of Strongyloides stercoralis infections is grossly underestimated because infections go mostly undetected, although they can persist for a lifetime due to the auto-infective cycle. In the Bolivian Chaco, the prevalence of soil-transmitted nematodes dropped dramatically in the past 25 years, but the mebendazole used for preventive chemotherapy has no effect on S. stercoralis. Meanwhile, the prevalence of intestinal protozoan infections remains unchanged. We compared S. stercoralis seroprevalence in rural communities of the Bolivian Chaco from 1987 to 2013. METHODS: Sera collected during two previous serosurveys, conducted in the Chaco region in 1987 and 2013, were tested for S. stercoralis using a commercial assay (Bordier-ELISA, Bordier Affinity Products, Switzerland). RESULTS: Overall, 355 sera were analysed, 122 from the 1987 survey and 233 from the 2013 survey. Seropositivity for S. stercoralis was significantly more prevalent in 1987 (19/122, 16% in 1987 vs. 15/233, 6% in 2013, P = 0.006), accounted for by a drop from 17% to 3% in people under 26 years of age. Multivariate analysis showed a significant association between seropositivity for S. stercoralis and age in the 2013 population (OR 1.03 for each one-year increase, 95%CI 1.00-1.05, P = 0.04), but none in 1987. CONCLUSIONS: The significant reduction in S. stercoralis seroprevalence in Bolivian Chaco cannot be explained by preventive chemotherapy or improved social-sanitary conditions. As the drop is seen in younger generations, it is consistent with little transmission occurring. However, the risk of transmission still exists, as prevalence is persistently high in older individuals, who present a potential reservoir due to the lifelong nature of S. stercoralis infections.
Asunto(s)
Parasitosis Intestinales/epidemiología , Población Rural , Strongyloides stercoralis/crecimiento & desarrollo , Estrongiloidiasis/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Animales , Bolivia/epidemiología , Niño , Preescolar , Femenino , Humanos , Lactante , Parasitosis Intestinales/transmisión , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Prevalencia , Estudios Seroepidemiológicos , Suelo/parasitología , Estrongiloidiasis/transmisión , Adulto JovenRESUMEN
One of the specificities of the Bolivian social formation is the coexistence of social and territorial organizations with a longstanding historical tradition. The current analysis focuses on the formation of citizenship in Bolivian society, in which the collective dimension is affirmed in the struggles, demands, and exercise of rights, as well as in the various modalities of extension of rights stemming from the state. The current study argues that during the neoliberal period in Bolivia, a series of policies oriented towards restructuring of the state deepened the collective dimension of citizenship as both status and participation, with the certificate of incorporation as the maximum symbolic expression.
L'une des spécificités de la formation sociale bolivienne est la coexistence d'organisations sociales et territoriales ayant une longue tradition historique. Dans cet article, on examine la formation de la citoyenneté dans la société bolivienne, là où la dimension collective s'affirme dans les luttes, les demandes et l'exercice des droits, ainsi que dans les modalités d'extension des droits accordés par l'État. On affirme ici que, pendant la période néolibérale en Bolivie, un ensemble de politiques orientées vers la restructuration de l'État a approfondi la dimension collective de la citoyenneté comme statut et comme participation, sa plus haute expression symbolique étant le document de la personnalité juridique.