Prevalence of and factors associated with childhood anaemia in remote villages of the Peruvian Amazon: a cross-sectional study and geospatial analysis.

BACKGROUND: Anaemia is a public health problem in Peru. In the Loreto region of the Amazon, ≥50% of children may be anaemic, although insufficient information exists for rural villages. METHODS: To generate more data about childhood anaemia in the Peruvian Amazon, haemoglobin was measured as part of a trachoma survey in 21 randomly selected villages. All children 1-9 y of age from 30 randomly selected households per village were recruited. Anaemia was classified according to the World Health Organization guidelines and a socio-economic status (SES) index was created for each household using principal component analysis. Spatial autocorrelation was determined using Moran's I and Ripley's K function. RESULTS: Of 678 children with complete haemoglobin data, 25.4% (95% confidence interval [CI] 21.2 to 30.1) had mild-or-worse anaemia and 22.1% (95% CI 15.6 to 30.3) had moderate-or-worse anaemia. Mild-or-worse anaemia was more common among children whose primary source of drinking water was surface water (prevalence ratio [PR] 1.26 [95% CI 1.14 to 1.40], p<0.001) and who were in the lowest SES tercile (PR 1.16 [95% CI 1.02 to 1.32], p=0.021). Moderate-or-worse anaemia was more common among boys (PR 1.32 [95% CI 1.09 to 1.60], p=0.005). No evidence of geospatial clustering was found. CONCLUSIONS: Remote villages of the Amazon would benefit from interventions for childhood anaemia and the poorest households would have the most to gain. Integrating anaemia screening into neglected tropical diseases surveys is an opportunity to use public health resources more efficiently.

Association of vision impairment and blindness with socioeconomic status in adults 50 years and older from Alto Amazonas, Peru.

OBJECTIVE: To determine the relationship between socioeconomic status (SES) and visual impairment (VI) or blindness in the rural Peruvian Amazon, hypothesizing that higher SES would have a protective effect on the odds of VI or blindness. METHODS: In this cross-sectional study of 16 rural communities in the Peruvian Amazon, consenting adults aged ≥ 50 years were recruited from ~30 randomly selected households per village. Each household was administered a questionnaire and had a SES score constructed using principal components analysis. Blindness and VI were determined using a ministry of health 3-meter visual acuity card. RESULTS: Overall, 207 adults aged ≥ 50 were eligible; 146 (70.5%) completed visual acuity screening and answered the questionnaire. Of those 146 participants who completed presenting visual acuity screening, 57 (39.0%, 95% CI 30.2-47.1) were classified as visually impaired and 6 (4.1%, 95% CI 0.9-7.3) as blind. Belonging to the highest SES tercile had a protective effect on VI or blindness (OR 0.29, 95% CI 0.09 to 0.91, p = 0.034), with a linear trend across decreasing levels of SES (p = 0.019). This observed effect remained significant regardless of how SES groups were assigned. CONCLUSION: Belonging to a higher SES group resulted in a lower odds of VI or blindness compared to those in the lowest SES group. The observation of a dose response provides confidence in the observed association, but causality remains unclear. Blindness prevention programs could maximize impact by designing activities that specifically target people with lower SES.

Associated factors of the co-occurrence of trachoma and soil-transmitted helminthiases in children 1 to 9 years old in rural communities of the Amazon basin in Loreto Department, Peru: Results from a population-based survey.

BACKGROUND: There is evidence of the occurrence of trachoma in Peru, and studies have shown that soil-transmitted helminthiases (STH) are affecting rural communities in the Amazon basin in Loreto Department. This study was done to estimate trachoma prevalence, STH prevalence, and the associated factors for both diseases in children aged 1-9 years in rural communities of Peru. METHODOLOGY: A population-based cross-sectional survey was carried out in rural communities of Loreto. A standardized survey questionnaire with individual and household risk factors related to both diseases was used. Ocular examination was done for all participants aged one year and above, and eye swab samples were collected from children with follicular trachoma (TF). Anthropometric measurements, stool samples for STH, and blood samples for hemoglobin measurement were taken from children. PRINCIPAL FINDINGS: TF prevalence was 7.74% (95% CI 5.08-11.63%), STH prevalence was 49.49% (95% CI 25.00-52.43%), and prevalence of co-occurrence of both diseases was 5.06% (95% CI 2.80-8.98%) in children aged 1-9 years. Being at age 3-8 years old (AOR = 6.76; 95% CI 1.346-33.947), have an unclean face (AOR = 24.64; 95% CI 6.787-89.444), and having been dewormed in the last six months (AOR = 2.47; 95% CI 1.106-5.514), were risk factors of TF. Being a female (AOR = 0.22; 95% CI 0.103-0.457) was associated with decreased odds of TF. Having been dewormed in the last six months (AOR = 0.30; 95% CI 0.139-0.628) was a preventative factor for STH. Risk factors for children with both diseases mirrored the findings for risk factors for individual diseases. CONCLUSIONS: Neglected tropical diseases and associated risk factors overlap in communities living in vulnerable conditions in the Amazon basin of Peru. These findings support the need to implement integrated interventions, including mass drug administration, water, sanitation, and hygiene for both diseases in the study area.

[River boats as a means of expansion of Aedes aegypti towards border zones of the peruvian amazon]. / Embarcaciones fluviales como medio de dispersión de Aedes aegypti hacia zonas fronterizas de la amazonia peruana.

OBJECTIVES.: To assess the entomological risk of Aedes aegypti in boats traversing border river routes in Loreto. MATERIALS AND METHODS.: The study population consisted of mosquitoes present in three boats covering border routes in Loreto. The entomological risk of Aedes was determined through ovitraps, the inspection of breeding sites, and the collection and taxonomic identification of adult mosquitoes. RESULTS.: The entomological risk varied according to the route and the season. A medium to very high entomological risk was identified in the high-water season and on the outward route to the border areas. The predominant vector population in the low-water season was Mansonia sp. (74.8%), Culex sp. (12.8%), and Aedes aegypti (0.4%); in the high-water season, Culex sp. (45.1%), Mansonia sp. (26.8%), and Aedes aegypti (19.7%). In no case did we find Aedes albopictus. CONCLUSIONS.: There is moderate to high entomological risk during the high-water season in riverboats traveling from Iquitos to the border areas of Loreto. Our results show that river boats are a means of expansion of Aedes aegypti.

OBJETIVOS.: Evaluar el riesgo entomológico de Aedes aegypti durante el recorrido fluvial en embarcaciones con rutas fronterizas de Loreto. MATERIALES Y MÉTODOS: . La población de estudio fueron los mosquitos presentes en tres embarcaciones con rutas fronterizas en Loreto. El riesgo entomológico de Aedes se determinó mediante ovitrampas, revisión de criaderos, colecta e identificación taxonómica de mosquitos adultos. RESULTADOS: . El riesgo entomológico varió según trayecto y época. Se identificó un riesgo entomológico medio a muy alto en época de creciente y en la ruta de ida hacia las zonas fronterizas. La población vectorial predominante en época de vaciante fue Mansonia sp. (74,8%), Culex sp. (12,8%) y Aedes aegypti (0,4%); en creciente predominó Culex sp. (45,1%), Mansonia sp. (26,8%) y Aedes aegypti (19,7%). En ningún caso se evidenció Aedes albopictus. CONCLUSIONES.: Existe riesgo entomológico de moderado a alto durante la etapa de creciente en las embarcaciones fluviales que viajan desde Iquitos hacia las zonas fronterizas de Loreto. Nuestros resultados evidencian que las embarcaciones fluviales son un medio de dispersión de Aedes aegypti.

Embarcaciones fluviales como medio de dispersión de Aedes aegypti hacia zonas fronterizas de la amazonia peruana / River boats as a means of expansion of Aedes aegypti towards border zones of the peruvian amazon

RESUMEN Objetivos. Evaluar el riesgo entomológico de Aedes aegypti durante el recorrido fluvial en embarcaciones con rutas fronterizas de Loreto. Materiales y métodos . La población de estudio fueron los mosquitos presentes en tres embarcaciones con rutas fronterizas en Loreto. El riesgo entomológico de Aedes se determinó mediante ovitrampas, revisión de criaderos, colecta e identificación taxonómica de mosquitos adultos. Resultados . El riesgo entomológico varió según trayecto y época. Se identificó un riesgo entomológico medio a muy alto en época de creciente y en la ruta de ida hacia las zonas fronterizas. La población vectorial predominante en época de vaciante fue Mansonia sp. (74,8%), Culex sp. (12,8%) y Aedes aegypti (0,4%); en creciente predominó Culex sp. (45,1%), Mansonia sp. (26,8%) y Aedes aegypti (19,7%). En ningún caso se evidenció Aedes albopictus. Conclusiones. Existe riesgo entomológico de moderado a alto durante la etapa de creciente en las embarcaciones fluviales que viajan desde Iquitos hacia las zonas fronterizas de Loreto. Nuestros resultados evidencian que las embarcaciones fluviales son un medio de dispersión de Aedes aegypti.

ABSTRACT Objectives. To assess the entomological risk of Aedes aegypti in boats traversing border river routes in Loreto. Materials and Methods. The study population consisted of mosquitoes present in three boats covering border routes in Loreto. The entomological risk of Aedes was determined through ovitraps, the inspection of breeding sites, and the collection and taxonomic identification of adult mosquitoes. Results. The entomological risk varied according to the route and the season. A medium to very high entomological risk was identified in the high-water season and on the outward route to the border areas. The predominant vector population in the low-water season was Mansonia sp. (74.8%), Culex sp. (12.8%), and Aedes aegypti (0.4%); in the high-water season, Culex sp. (45.1%), Mansonia sp. (26.8%), and Aedes aegypti (19.7%). In no case did we find Aedes albopictus. Conclusions. There is moderate to high entomological risk during the high-water season in riverboats traveling from Iquitos to the border areas of Loreto. Our results show that river boats are a means of expansion of Aedes aegypti.