Improving knowledge, attitudes, and practices on dengue and diarrhea in rural primary school students, their parents, and teachers in Colombia: A cluster-randomized controlled trial.

BACKGROUND: Improved education on water-related diseases in schools could help to reduce disease burden. This paper presents specific results on knowledge, attitudes and practices (KAP) of a cluster-randomized controlled trial to reduce diarrheal disease and dengue entomological risk factors in rural primary schools in Colombia. The aim was to investigate whether enhanced educational interventions on dengue and diarrheal disease in schools could improve KAP scores related to these diseases in students and teachers in rural primary schools, as well as the students' parents. METHODOLOGY/PRINCIPAL FINDINGS: A factorial cluster-randomized controlled trial was carried out in 35 rural primary schools in two municipalities in Cundinamarca, central Colombia. Schools were randomized into four arms: interventions related to diarrheal disease (DIA), dengue (DEN), both (DIADEN), or no interventions (control, CON). Both educational and physical interventions to reduce risk factors of dengue and diarrhea were implemented. Comprehensive teachers' manuals were developed and deployed to guide the learning activities. The intervention was carried out over two school years. The knowledge scores of students receiving dengue interventions (DEN, DIADEN) increased by 1.16 point score (0.75-1.56, p<0.001) and those receiving diarrhea interventions (DIA, DIADEN) increased by 1.15 point score (0.67-1.63, p<0.001). The attitude and practice scores of students receiving the diarrhea interventions increased (Attitudes: 0.41 [0.11-0.71, p = 0.01]; Practices: 0.33 [0.01-0.65, p = 0.042]), but not for those receiving the dengue interventions (p = 0.31 and p = 0.08, respectively). CONCLUSIONS/SIGNIFICANCE: There were increases in knowledge scores among students, their teachers and their parents for both diseases. However, the attitudes and practices components were not affected to the same extent. The hypothesis that the students would disseminate knowledge acquired from the educational interventions to their parents was confirmed for dengue, but not for diarrhea. TRIAL REGISTRATION: ISRCTN40195031 The trial is registered in the Current Controlled Trials under Infections and Infestations category.

Reasons for absenteeism in rural primary schools in two Colombian municipalities / Razones de ausentismo en escuelas primarias rurales de dos municipios colombianos / Razões do não comparecimento nas escolas primarias rurais nos municípios colombianos

Background: School absenteeism is a considerable problem generally related to higher dropout rates, poor academic achievement and school lag. This study determined the frequency and causes of overall and illness-related absenteeism of students in rural schools from two Colombian municipalities. Methods: A prospective and descriptive study was conducted in a population of 948 school children from 34 rural schools. Absenteeism data were collected for 2013 academic year consisted of the number of students registered and absent by grade, school, day and reason for absence. Absence rates (overall and illness-related absenteeism) were recorded, based on full or partial days absence, measured both as episodes, and accumulating the number of days. Results: From the students included in the study, 55.1% were male and 71.6% were between 5 and 9 years old. The overall absence rate was 5.7 episodes per child-year (95% confidence interval 5.5 to 5.8) and 8.6 days per child-year (8.4 to 8.9). The main reasons for non-attendance were illness (24.4%), medical or dental check-up (12.9%), travel (12.3%), lack of motivation to attend school (10.0%) and bad weather (9.3%). The illness- related absence rate was 1.4 episodes per child-year (95% confidence interval 1.3 to 1.5) and 2.5 days per child-year (2.4 to 2.6). The main reasons for illness-related absence were cold (37.0%), nonspecific fever (10.9%) and stomach pain or vomiting (8.4%). Conclusions: In this study, the most common reasons for non-attendance were illness-related. The importance of respiratory and gastrointestinal infections in absenteeism was evident, showing rates similar to other urban school studies. Then, the results of this study provide knowledge on the magnitude and reasons for absenteeism in rural schoolchildren.

Antecedentes. El ausentismo escolar es un problema importante relacionado con altas tasas de abandono escolar, bajo rendimiento académico y rezago escolar. Este estudio determinó la frecuencia y las causas del ausentismo general y el ausentismo relacionado con la enfermedad en estudiantes de escuelas rurales de dos municipios de Colombia. Métodos. Se realizó un estudio descriptivo en una población de 948 escolares de 34 escuelas rurales. Los datos de ausentismo recopilados para el año 2013 consistieron en el número de episodios y días de ausentismo por grado y motivo de ausencia general y por enfermedad. Se calcularon las tasas de ausentismo general y por enfermedad. Resultados. El 55,1% de la población participante eran hombres y el 71,6% tenían entre 5 y 9 años. La tasa de ausentismo general fue 5,7 episodios por niño-año, IC 95% (5,5-5,8) y 8,6 días por niño-año, IC 95% (8,4-8,9). Las principales razones del ausentismo fueron enfermedades (24,4%), chequeo médico u odontológico (12,9%), viajes (12,3%), falta de motivación para asistir a la escuela (10,0%) y mal clima (9,3%). La tasa de ausentismo por enfermedad fue 1,4 episodios por niño-año IC 95% (1,3-1,5) y 2,5 días por niño-año IC 95% (2,4-2,6). Las principales razones del ausentismo por enfermedad fueron el resfriado común (37,0%), la fiebre inespecífica (10,9%) y el dolor de estómago o vómito (8,4%). Conclusiones. Las razones más comunes para la no asistencia estuvieron relacionadas con la enfermedad. La importancia de las infecciones respiratorias y gastrointestinales en el absentismo fue evidente, mostrando tasas similares a las de otros estudios en escuelas urbanas. Los resultados de este estudio proporcionan conocimiento sobre la magnitud y las razones del absentismo en la población escolar rural.

Antecedentes. O absentismo escolar é um grande problema relacionado às altas taxas de evasão escolar, baixo desempenho acadêmico e atraso escolar. Este estudo determinou a frequência e causas do não comparecimento geral e por doenças em estudantes de escolas rurais de dois municípios da Colômbia. Métodos. Estudo descritivo, realizado em uma população de 948 escolares de 34 escolas rurais. Os dados de absentismo coletados para 2013 consistiram no número de episódios e dias de não comparecimento por grau e motivo da ausência geral e por doença, foram calculadas as taxas de cada evento. Resultados. 55,1% da população participante eram crianças masculinas do primeiro grau, 71,6% entre 5 e 9 anos de idade. A taxa geral de absentismo foi de 5,7 episódios por criança-ano, IC95% (5,5-5,8) e 8,6 dias por criança-ano, IC95% (8,4-8,9). Os principais motivos do não comparecimento foram doenças (24,4%), check-up médico ou odontológico (12,9%), viagens (12,3%), falta de motivação para frequentar a escola (10,0%) e mau tempo (9,3%). A taxa de absentismo da doença foi de 1,4 episódios por IC95% criança-ano (1,3-1,5) e 2,5 dias por IC95% criança-ano (2,4-2,6). Os principais motivos da ausência de doença foram resfriado comum (37,0%), febre inespecífica (10,9%) e dor de estômago ou vômito (8,4%). Conclusões. Os motivos mais comuns de não comparecimento foram relacionados à doença. A importância das infecções respiratórias e gastrointestinais no absenteísmo foi evidente, mostrando taxas semelhantes às de outros estudos em escolas urbanas. Os resultados deste estudo fornecem informações sobre a magnitude e as razões para evasão escolar na população escolar rural.

Knowledge, attitudes, and practices about dengue among pupils from rural schools in an endemic area in Colombia / Conocimientos, actitudes y prácticas sobre dengue en estudiantes de escuelas rurales de un área endémica en Colombia

INTRODUCTION: Dengue is a public health problem in tropical and subtropical regions of the world. Studies on dengue in rural areas are scarce since the disease is considered mainly urban. OBJECTIVE: To determine the knowledge (K), attitudes (A) and practices (P) of dengue in an endemic area in Colombia. MATERIALS AND METHODS: We conducted a cross-sectional study with 515 pupils (7-16 years old) in 34 rural schools in Anapoima and La Mesa municipalities during 2011. Each KAP category was evaluated independently by a scoring system and then categorized into high, medium or low. RESULTS: Pupils recognized knowledge variables such as the symptoms (fever, bone pain), transmission route (mosquito bites), and mosquito breeding sites (uncovered water tanks, solid waste). Average scores on attitude were high in both municipalities indicating a well-developed perception of disease severity. Seeking treatment in medical centers and self-medication for fever management and the use of mosquito net and space-spraying of insecticides were the most frequently identified practices. DISCUSSION: This is the first KAP dengue study performed in a rural area in Colombia and as such it contributes to the understanding of dengue perceptions by the inhabitants of these areas. It showed a medium level of knowledge about dengue and a lower level of preventive practices in pupils from rural schools. It also showed that pupils considered space-spraying as crucial for vector control. The presence of the vector in rural areas of the country underlines the need to improve surveillance and education to more effectively control the vector and promote prevention methods including community participation.

Introducción. El dengue es un problema de salud pública en las regiones tropicales y subtropicales del mundo. Los estudios sobre la enfermedad en áreas rurales son escasos debido a que se presenta principalmente en los núcleos urbanos. Objetivo. Determinar los conocimientos, las actitudes y las prácticas sobre el dengue en un área rural endémica en Colombia. Materiales y métodos. Se hizo un estudio transversal con 515 estudiantes, entre los 7 y los 16 años de edad en 34 escuelas rurales de los municipios de Anapoima y La Mesa en el 2011. Cada categoría se evaluó por separado con un puntaje clasificado como alto, medio o bajo. Resultados. Los estudiantes reconocieron los síntomas (fiebre, dolor de huesos), la ruta de transmisión (picadura de mosquitos) y los criaderos (depósitos de agua destapados, residuos sólidos). El promedio de los puntajes de actitudes fue alto en ambos municipios, lo que indica que percibían la gravedad del dengue. Las prácticas más frecuentes de tratamiento de la fiebre fueron la consulta médica y la automedicación, en tanto que los métodos de control más frecuentes fueron el uso de mosquiteros y el rociamiento con insecticidas. Discusión. Este es el primer estudio de conocimientos, actitudes y prácticas sobre el dengue en un área rural de Colombia. Los resultados contribuyen a entender las percepciones de la enfermedad en sus habitantes y evidenciaron niveles medios de conocimiento y puntuaciones bajas en cuanto a las prácticas entre los estudiantes de las escuelas rurales. Los estudiantes consideraron que la fumigación es importante para el control del vector. La presencia del mosquito en áreas rurales del país resalta la necesidad de mejorar la vigilancia y la educación para lograr un control efectivo del vector y promover métodos de prevención que incluyan la participación comunitaria.

Knowledge, attitudes and practices about dengue among pupils from rural schools in Colombia / Conocimientos, actitudes y prácticas sobre dengue en estudiantes de escuelas rurales en Colombia

Abstract Introduction: Dengue is a public health problem in tropical and subtropical regions of the world. Studies on dengue in rural areas are scarce since the disease is considered mainly urban. Objective: To determine the knowledge (K), attitudes (A) and practices (P) of dengue in an endemic area in Colombia. Materials and methods: We conducted a cross-sectional study with 515 pupils (7-16 years old) in 34 rural schools in Anapoima and La Mesa municipalities during 2011. Each KAP category was evaluated independently by a scoring system and then categorized into high, medium or low. Results: Pupils recognized knowledge variables such as the symptoms (fever, bone pain), transmission route (mosquito bites), and mosquito breeding sites (uncovered wáter tanks, solid waste). Average scores on attitude were high in both municipalities indicating a well-developed perception of disease severity. Seeking treatment in medical centers and self-medication for fever management and the use of mosquito net and space-spraying of insecticides were the most frequently identified practices. Discussion: This is the first KAP dengue study performed in a rural area in Colombia and as such it contributes to the understanding of dengue perceptions by the inhabitants of these areas. It showed a medium level of knowledge about dengue and a lower level of preventive practices in pupils from rural schools. It also showed that pupils considered space-spraying as crucial for vector control. The presence of the vector in rural areas of the country underlines the need to improve surveillance and education to more effectively control the vector and promote prevention methods including community participation.

Resumen Introducción. El dengue es un problema de salud pública en las regiones tropicales y subtropicales del mundo. Los estudios sobre la enfermedad en áreas rurales son escasos debido a que se presenta principalmente en los núcleos urbanos. Objetivo. Determinar los conocimientos, las actitudes y las prácticas sobre el dengue en un área rural endémica en Colombia. Materiales y métodos. Se hizo un estudio transversal con 515 estudiantes, entre los 7 y los 16 años de edad en 34 escuelas rurales de los municipios de Anapoima y La Mesa en el 2011. Cada categoría se evaluó por separado con un puntaje clasificado como alto, medio o bajo. Resultados. Los estudiantes reconocieron los síntomas (fiebre, dolor de huesos), la ruta de transmisión (picadura de mosquitos) y los criaderos (depósitos de agua destapados, residuos sólidos). El promedio de los puntajes de actitudes fue alto en ambos municipios, lo que indica que percibían la gravedad del dengue. Las prácticas más frecuentes de tratamiento de la fiebre fueron la consulta médica y la automedicación, en tanto que los métodos de control más frecuentes fueron el uso de mosquiteros y el rociamiento con insecticidas. Discusión. Este es el primer estudio de conocimientos, actitudes y prácticas sobre el dengue en un área rural de Colombia. Los resultados contribuyen a entender las percepciones de la enfermedad en sus habitantes y evidenciaron niveles medios de conocimiento y puntuaciones bajas en cuanto a las prácticas entre los estudiantes de las escuelas rurales. Los estudiantes consideraron que la fumigación es importante para el control del vector. La presencia del mosquito en áreas rurales del país resalta la necesidad de mejorar la vigilancia y la educación para lograr un control efectivo del vector y promover métodos de prevención que incluyan la participación comunitaria.

[Spatial distribution of Aedes aegypti (Diptera: Culicidae) in the rural area of two municipalities of Cundinamarca, Colombia].

INTRODUCTION: It is difficult to adapt or create new strategies for dengue control in rural areas due to the dispersion of homes and the lack of knowledge about the presence and behavior of the vector in these areas. Spatial data analysis could help understand time and space dynamics related to the transmission of vector-borne diseases in rural areas and, thus, contribute to the prevention and control of dengue. OBJECTIVE: To determine the probability of the presence of the dengue vector Aedes aegypti in the rural area of the municipalities of Anapoima and La Mesa, in the central area of Colombia. MATERIALS AND METHODS: The probability of the presence or absence of the vector in the study area was determined by means of the kriging spatial interpolation method. RESULTS: The region with the highest probability of the presence of the vector was located in the central part, close to the urban centers of both municipalities. CONCLUSION: This study shows the importance of geostatistics for the surveillance of vector-borne diseases and the analysis of time and space dynamics of vector insects and of diseases transmitted by them.

Dengue virus detection in Aedes aegypti larvae and pupae collected in rural areas of Anapoima, Cundinamarca, Colombia.

INTRODUCTION: There is a high incidence and prevalence of dengue in the department of Cundinamarca, and recently Aedes aegypti, the main vector of dengue virus (DENV), was detected in some of its rural areas. OBJECTIVE: To evaluate viral transovarial transmission in larvae and pupae collected in rural areas of the municipality of Anapoima, Cundinamarca. MATERIALS AND METHODS: Live larvae and pupae were collected from 53 homes and later they were taken to the laboratory in Anapoima, where they were classified, pooled and frozen. In Bogotá, they were homogenized, RNA was extracted with Trizol™, and RT-PCR and conventional PCR were performed. The amplified products were analyzed on 2% agarose gels. RESULTS: In 54.7% of the houses we found A. aegypti in immature stages, and DENV-1 was the most frequent serotype. However, the simultaneous presence of DENV 1 and 2, DENV 1 and 3, DENV 1 and 4, and DENV 1, 2 and 3 serotypes was detected in some pools. CONCLUSION: The results confirmed the natural vertical transmission of the virus in the rural area under study. These findings confirmed the vector capacity of A. aegypti, and partly explains the persistence of the virus in the region and the possibility of transmission by the vector during adulthood without having ingested infected blood. This situation increases the risk of DENV infection in Colombia and the need for prevention and control programs in all areas where the mosquito is present.

Distribución espacial de Aedes aegypti (Diptera: Culicidae) en el área rural de dos municipios de Cundinamarca, Colombia / Spatial distribution of Aedes aegypti (Diptera: Culicidae) in the rural area of two municipalities of Cundinamarca, Colombia

Resumen Introducción. Es difícil adaptar o formular nuevas estrategias para el control del dengue en las áreas rurales debido a la dispersión de los hogares y a la falta de conocimiento sobre la presencia y el comportamiento del vector en estas áreas. El análisis de los datos espaciales podría ayudar a comprender las dinámicas temporales y espaciales relacionadas con la transmisión de enfermedades transmitidas por vectores en las zonas rurales y, por lo tanto, contribuir a la prevención y el control del dengue. Objetivo. Determinar la probabilidad de la presencia del vector del dengue, Aedes aegypti, en el área rural de los municipios de Anapoima y La Mesa, Cundinamarca, Colombia. Materiales y métodos. Se visitaron 102 viviendas del área rural, se inspeccionaron los criaderos potenciales del mosquito A. aegypti y se capturaron las formas adultas encontradas en su interior. La probabilidad de la presencia o la ausencia del vector en el área de estudio, se estableció mediante el método de interpolación espacial kriging. Resultados. La región con mayor probabilidad para la presencia del vector se encontró en la parte central, cerca de los centros urbanos de los dos municipios. Conclusión. Los análisis de las dinámicas espacio-temporales de los vectores de enfermedades pueden utilizarse en los sistemas para su vigilancia, con el fin de complementar los métodos usados actualmente, optimizar la determinación de las áreas de intervención de control vectorial y ahorrar recursos.

Abstract Introduction: It is difficult to adapt or create new strategies for dengue control in rural areas due to the dispersion of homes and the lack of knowledge about the presence and behavior of the vector in these areas. Spatial data analysis could help understand time and space dynamics related to the transmission of vector-borne diseases in rural areas and, thus, contribute to the prevention and control of dengue. Objective: To determine the probability of the presence of the dengue vector Aedes aegypti in the rural area of the municipalities of Anapoima and La Mesa, in the central area of Colombia. Materials and methods: The probability of the presence or absence of the vector in the study area was determined by means of the kriging spatial interpolation method. Results: The region with the highest probability of the presence of the vector was located in the central part, close to the urban centers of both municipalities. Conclusion: This study shows the importance of geostatistics for the surveillance of vector-borne diseases and the analysis of time and space dynamics of vector insects and of diseases transmitted by them.

A cross-sectional survey of Aedes aegypti immature abundance in urban and rural household containers in central Colombia.

BACKGROUND: Aedes aegypti, the major vector of dengue, breeds in domestic water containers. The development of immature mosquitoes in such containers is influenced by various environmental, ecological and socioeconomic factors. Urban and rural disparities in water storage practices and water source supply may affect mosquito immature abundance and, potentially, dengue risk. We evaluated the effect of water and container characteristics on A. aegypti immature abundance in urban and rural areas. Data were collected in the wet season of 2011 in central Colombia from 36 urban and 35 rural containers, which were either mosquito-positive or negative. Immature mosquitoes were identified to species. Data on water and container characteristics were collected from all containers. RESULTS: A total of 1452 Aedes pupae and larvae were collected of which 81% were A. aegypti and 19% A. fluviatilis. Aedes aegypti immatures were found in both urban and rural sites. However, the mean number of A. aegypti pupae was five times higher in containers in the urban sites compared to those in the rural sites. One of the important factors associated with A. aegypti infestation was frequency of container washing. Monthly-washed or never-washed containers were both about four times more likely to be infested than those washed every week. There were no significant differences between urban and rural sites in frequency of washing containers. Aedes aegypti immature infestation was positively associated with total dissolved solids, but negatively associated with dissolved oxygen. Water temperature, total dissolved solids, ammonia, nitrate, and organic matter were significantly higher in urban than in rural containers, which might explain urban-rural differences in breeding of A. aegypti. However, many of these factors vary substantially between studies and in their degree of association with vector breeding, therefore they may not be reliable indices for vector control interventions. CONCLUSIONS: Although containers in urban areas were more likely to be infested with A. aegypti, rural containers still provide suitable habitats for A. aegypti. Containers that are washed more frequent are less likely to produce A. aegypti. These results highlight the importance of container washing as an effective vector control tool in both urban and rural areas. In addition, alternative designs of the highly productive washbasins should continue to be explored. To control diseases such as dengue, Zika and chikungunya, effective vector breeding site control must be implemented in addition to other interventions.

A Cluster-Randomized Controlled Trial to Reduce Diarrheal Disease and Dengue Entomological Risk Factors in Rural Primary Schools in Colombia.

BACKGROUND: As many neglected tropical diseases are co-endemic and have common risk factors, integrated control can efficiently reduce disease burden and relieve resource-strained public health budgets. Diarrheal diseases and dengue fever are major global health problems sharing common risk factors in water storage containers. Where provision of clean water is inadequate, water storage is crucial. Fecal contamination of stored water is a common source of diarrheal illness, but stored water also provides breeding sites for dengue vector mosquitoes. Integrating improved water management and educational strategies for both diseases in the school environment can potentially improve the health situation for students and the larger community. The objective of this trial was to investigate whether interventions targeting diarrhea and dengue risk factors would significantly reduce absence due to diarrheal disease and dengue entomological risk factors in schools. METHODOLOGY/PRINCIPAL FINDINGS: A factorial cluster randomized controlled trial was carried out in 34 rural primary schools (1,301 pupils) in La Mesa and Anapoima municipalities, Cundinamarca, Colombia. Schools were randomized to one of four study arms: diarrhea interventions (DIA), dengue interventions (DEN), combined diarrhea and dengue interventions (DIADEN), and control (CON). Interventions had no apparent effect on pupil school absence due to diarrheal disease (p = 0.45) or on adult female Aedes aegypti density (p = 0.32) (primary outcomes). However, the dengue interventions reduced the Breteau Index on average by 78% (p = 0.029), with Breteau indices of 10.8 and 6.2 in the DEN and DIADEN arms, respectively compared to 37.5 and 46.9 in the DIA and CON arms, respectively. The diarrhea interventions improved water quality as assessed by the amount of Escherichia coli colony forming units (CFU); the ratio of Williams mean E. coli CFU being 0.22, or 78% reduction (p = 0.008). CONCLUSIONS/SIGNIFICANCE: Integrated control of dengue and diarrhea has never been conducted before. This trial presents an example for application of control strategies that may affect both diseases and the first study to apply such an approach in school settings. The interventions were well received and highly appreciated by students and teachers. An apparent absence of effect in primary outcome indicators could be the result of pupils being exposed to risk factors outside the school area and mosquitoes flying in from nearby uncontrolled breeding sites. Integrated interventions targeting these diseases in a school context remain promising because of the reduced mosquito breeding and improved water quality, as well as educational benefits. However, to improve outcomes in future integrated approaches, simultaneous interventions in communities, in addition to schools, should be considered; using appropriate combinations of site-specific, effective, acceptable, and affordable interventions. TRIAL REGISTRATION: ClinicalTrials.gov no. ISRCTN40195031.

Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia.

The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

Schools as Potential Risk Sites for Vector-Borne Disease Transmission: Mosquito Vectors in Rural Schools in Two Municipalities in Colombia.

Dengue and other vector-borne diseases are of great public health importance in Colombia. Vector surveillance and control activities are often focused at the household level. Little is known about the importance of nonhousehold sites, including schools, in maintaining vector-borne disease transmission. The objectives of this paper were to determine the mosquito species composition in rural schools in 2 municipalities in Colombia and to assess the potential risk of vector-borne disease transmission in school settings. Entomological surveys were carried out in rural schools during the dry and rainy seasons of 2011. A total of 12 mosquito species were found: Aedes aegypti, Anopheles pseudopunctipennis, Culex coronator, Cx. quinquefasciatus, and Limatus durhamii in both immature and adult forms; Ae. fluviatilis, Cx. nigripalpus, Cx. corniger, and Psorophora ferox in immature forms only; and Ae. angustivittatus, Haemagogus equinus, and Trichoprosopon lampropus in adult forms only. The most common mosquito species was Cx. quinquefasciatus. Classrooms contained the greatest abundance of adult female Ae. aegypti and Cx. quinquefasciatus. The most common Ae. aegypti breeding sites were containers classified as "others" (e.g., cans), followed by containers used for water storage. A high level of Ae. aegypti infestation was found during the wet season. Our results suggest that rural schools are potentially important foci for the transmission of dengue and other mosquito-borne diseases. We propose that public health programs should be implemented in rural schools to prevent vector-borne diseases.

Control de diarrea y dengue en escuelas primarias rurales de Colombia: protocolo de estudio para un ensayo aleatorio y controlado por conglomerados / Diarrhea and dengue control in rural primary schools in Colombia: study protocol for a randomized controlled trial

Antecedentes. Las enfermedades diarreicas y el dengue son graves problemas de salud pública a nivel global. Cuando el suministro de agua potable es inadecuado, el almacenamiento de agua es crucial. La contaminación fecal del agua almacenada es una fuente común de las enfermedades diarreicas y, al mismo tiempo, el agua almacenada proporciona criaderos para los mosquitos vectores del dengue. Un manejo deficiente del agua doméstica y del saneamiento son, por lo tanto, determinantes potenciales de ambas enfermedades. Poco se sabe de la importancia del agua almacenada para el riesgo combinado de la diarrea y el dengue, sin embargo, una intervención compartida podría ser importante para el desarrollo de esfuerzos en gestión y control integrado. Aun menos conocidos son los efectos de un control integrado de estas enfermedades en los entornos escolares. El objetivo de este estudio fue investigar si las intervenciones contra la diarrea y el dengue reducían significativamente las enfermedades diarreicas y los factores de riesgo entomológico de dengue, en las escuelas primarias rurales de dos municipios de Cundinamarca. Metodología y diseño. Se trata de un ensayo por conglomerados, factorial de 2 x 2, controlado y de asignación aleatoria. Las instituciones elegibles fueron las escuelas rurales de los municipios de La Mesa y Anapoima en el departamento de Cundinamarca. Los estudiantes elegibles fueron los niños de las escuelas de los grados 0 a 5. Las escuelas fueron asignadas aleatoriamente a uno de los cuatro grupos del estudio: intervenciones de diarrea, intervenciones de dengue, las dos intervenciones, diarrea y dengue, y control. Las escuelas fueron estratificadas por municipio y asignadas mediante un acto público al inicio del ensayo. La variable de respuesta primaria para la diarrea fue la tasa de incidencia de diarrea en los niños de las escuelas, y para dengue, la densidad de adultos hembra de Aedes aegypti por escuela. Aproximadamente...

Background: Diarrheal diseases and dengue fever are major global health problems. Where provision of clean water is inadequate, water storage is crucial. Fecal contamination of stored water is a common source of diarrheal illness, but stored water also provides breeding sites for dengue vector mosquitoes. Poor household water management and sanitation are therefore potential determinants of both diseases. Little is known of the role of stored water for the combined risk of diarrhea and dengue, yet a joint role would be important for developing integrated control and management efforts. Even less is known of the effect of integrating control of these diseases in school settings. The objective of this trial was to investigate whether interventions against diarrhea and dengue will significantly reduce diarrheal disease and dengue entomological risk factors in rural primary schools. Methods/design: This is a 2×2 factorial cluster randomized controlled trial. Eligible schools were rural primary schools in La Mesa and Anapoima municipalities, Cundinamarca, Colombia. Eligible pupils were school children in grades 0 to 5. Schools were randomized to one of four study arms: diarrhea interventions (DIA); dengue interventions (DEN); combined diarrea and dengue interventions (DIADEN); and control (C). Schools were allocated publicly in each municipality (strata) at the start of the trial, obviating the need for allocation concealment. The primary outcome for diarrea is incidence rate of diarrhea in school children and for dengue it is density of adult female Aedes aegypti per school. Approximately 800 pupils from 34 schools were enrolled in the trial with eight schools in the DIA arm, nine in the DEN, eight in the DIADEN, and nine in the control arms. The trial was funded by the Research Council of Norway and the Lazos de Calandaima Foundation. Discussion: This is the first trial investigating...

Diarrhea and dengue control in rural primary schools in Colombia: study protocol for a randomized controlled trial.

BACKGROUND: Diarrheal diseases and dengue fever are major global health problems. Where provision of clean water is inadequate, water storage is crucial. Fecal contamination of stored water is a common source of diarrheal illness, but stored water also provides breeding sites for dengue vector mosquitoes. Poor household water management and sanitation are therefore potential determinants of both diseases. Little is known of the role of stored water for the combined risk of diarrhea and dengue, yet a joint role would be important for developing integrated control and management efforts. Even less is known of the effect of integrating control of these diseases in school settings. The objective of this trial was to investigate whether interventions against diarrhea and dengue will significantly reduce diarrheal disease and dengue entomological risk factors in rural primary schools. METHODS/DESIGN: This is a 2×2 factorial cluster randomized controlled trial. Eligible schools were rural primary schools in La Mesa and Anapoima municipalities, Cundinamarca, Colombia. Eligible pupils were school children in grades 0 to 5. Schools were randomized to one of four study arms: diarrhea interventions (DIA); dengue interventions (DEN); combined diarrhea and dengue interventions (DIADEN); and control (C). Schools were allocated publicly in each municipality (strata) at the start of the trial, obviating the need for allocation concealment. The primary outcome for diarrhea is incidence rate of diarrhea in school children and for dengue it is density of adult female Aedes aegypti per school. Approximately 800 pupils from 34 schools were enrolled in the trial with eight schools in the DIA arm, nine in the DEN, eight in the DIADEN, and nine in the control arms. The trial status as of June 2012 was: completed baseline data collections; enrollment, randomization, and allocation of schools. The trial was funded by the Research Council of Norway and the Lazos de Calandaima Foundation. DISCUSSION: This is the first trial investigating the effect of a set of integrated interventions to control both dengue and diarrhea. This is also the first trial to study the combination of diarrhea-dengue disease control in school settings. TRIAL REGISTRATION: Current Controlled Trials ISRCTN40195031.