Seroepidemiological trend of strongyloidiasis in the Bolivian Chaco (1987-2013) in the absence of disease-specific control measures.
Trop Med Int Health
; 22(11): 1457-1462, 2017 11.
Article
en En
| MEDLINE
| ID: mdl-28929562
ABSTRACT
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.Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Población Rural
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Estrongiloidiasis
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Strongyloides stercoralis
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Parasitosis Intestinales
Tipo de estudio:
Etiology_studies
/
Prevalence_studies
/
Risk_factors_studies
Límite:
Adolescent
/
Adult
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Aged
/
Animals
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Child
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Child, preschool
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Female
/
Humans
/
Infant
/
Male
País/Región como asunto:
America do sul
/
Bolivia
Idioma:
En
Revista:
Trop Med Int Health
Asunto de la revista:
MEDICINA TROPICAL
/
SAUDE PUBLICA
Año:
2017
Tipo del documento:
Article
País de afiliación:
Italia