Quality evaluation of malaria diagnosis in the local laboratories network and in intermediate laboratories in a setting towards the disease elimination in Ecuador / Evaluación de la calidad del diagnóstico de malaria en la red local de laboratorios y en los laboratorios intermedios en el contexto de la eliminación de la enfermedad en Ecuador

Introduction: To reach the goal of malaria elimination in Ecuador for the year 2020, it is necessary to have a laboratory network with the capacity to perform microscopic diagnosis according to the WHO/PAHO quality standards and to provide the adequate treatment of cases. Objective: To determine the level of competence for parasitological diagnosis of the microscopists from the local public network and the performance of intermediate reference laboratories. Materials and methods: We conducted a cross-sectional study based on the information collected in workshops carried out to appraise the competence for microscopic diagnosis of the local laboratory network (zonal health coordinating offices 1 to 8) using a slide panel to evaluate diagnosis agreement, as well as the diagnostic performance of the intermediate laboratories using an external quality assessment program. The results were compared against the reference standards of the supranational laboratory in Perú. Results: We evaluated the competencies of 191 microscopists in 11 workshops and 153 (80.1%) of them were approved. The medians of the indicators were the following: concordance for parasite detection, 100% (Q1- Q3: 96-100), concordance for species identification, 100% (Q1- Q3: 93-100), and concordances for stage identification, 93.0% (Q1- Q3: 86-95) and parasite counting, 77.0% (Q1- Q3: 71-82). In the external quality assessment, the three intermediate laboratories obtained 100% in parasite detection concordance and 96% for species detection concordance. Conclusions: The results for the primary network and the performance indicators for the intermediate laboratories showed the high-quality standards of the training program implemented in the country.

Introducción. El cumplimiento de la meta de eliminación de la malaria en Ecuador en el 2020 exige contar con la capacidad requerida para el diagnóstico microscópico ajustado a los estándares de calidad de la Organización Mundial de la Salud (OMS) y de la Organización Panamericana de la Salud (OPS) y proveer el tratamiento adecuado a los pacientes. Objetivo. Conocer la idoneidad o competencia de los microscopistas de la red pública local para el diagnóstico parasitológico de la malaria y el desempeño de los laboratorios intermedios de referencia. Materiales y métodos. Se hizo un estudio descriptivo de corte transversal a partir de la información obtenida en los talleres de evaluación de idoneidad en el diagnóstico microscópico de la red de laboratorios en las coordinaciones zonales de salud utilizando un panel de láminas para evaluar la concordancia del diagnóstico. Además, se calificó el desempeño de los laboratorios intermedios en el diagnóstico en el marco del programa de evaluación externa del desempeño. Los resultados se compararon con los obtenidos por el laboratorio supranacional de Perú. Resultados. En los 11 talleres realizados, se evaluó la idoneidad de 191 microscopistas, de los cuales 153 (80,1 %) aprobaron las pruebas. Las medianas de los indicadores fueron las siguientes: concordancia entre la detección y el resultado, 100 % (Q1- Q3: 96-100); concordancia en la especie, 100 % (Q1- Q3: 93-100); concordancia en el estadio, 93,0 % (Q1- Q3: 86-95) y concordancia en el recuento, 77 % (Q1- Q3: 71-82). En el programa de evaluación externa de desempeño, los tres laboratorios intermedios obtuvieron una concordancia del 100 % en el resultado y una del 96 % en la especie. Conclusiones. Los indicadores de competencia de la red local y de desempeño de los laboratorios intermedios alcanzaron altos estándares de calidad acordes con el proceso de entrenamiento implementado en el país.

Evaluación de la calidad del diagnóstico de malaria en la red local de laboratorios y en los laboratorios intermedios en el contexto de la eliminación de la enfermedad en Ecuador / Quality evaluation of malaria diagnosis in the local laboratories network and in intermediate laboratories in a setting towards the disease elimination in Ecuador

Resumen Introducción. El cumplimiento de la meta de eliminación de la malaria en Ecuador en el 2020 exige contar con la capacidad requerida para el diagnóstico microscópico ajustado a los estándares de calidad de la Organización Mundial de la Salud (OMS) y de la Organización Panamericana de la Salud (OPS) y proveer el tratamiento adecuado a los pacientes. Objetivo. Conocer la idoneidad o competencia de los microscopistas de la red pública local para el diagnóstico parasitológico de la malaria y el desempeño de los laboratorios intermedios de referencia. Materiales y métodos. Se hizo un estudio descriptivo de corte transversal a partir de la información obtenida en los talleres de evaluación de idoneidad en el diagnóstico microscópico de la red de laboratorios en las coordinaciones zonales de salud utilizando un panel de láminas para evaluar la concordancia del diagnóstico. Además, se calificó el desempeño de los laboratorios intermedios en el diagnóstico en el marco del programa de evaluación externa del desempeño. Los resultados se compararon con los obtenidos por el laboratorio supranacional de Perú. Resultados. En los 11 talleres realizados, se evaluó la idoneidad de 191 microscopistas, de los cuales 153 (80,1 %) aprobaron las pruebas. Las medianas de los indicadores fueron las siguientes: concordancia entre la detección y el resultado, 100 % (Q1- Q3: 96-100); concordancia en la especie, 100 % (Q1- Q3: 93-100); concordancia en el estadio, 93,0 % (Q1- Q3: 86-95) y concordancia en el recuento, 77 % (Q1- Q3: 71-82). En el programa de evaluación externa de desempeño, los tres laboratorios intermedios obtuvieron una concordancia del 100 % en el resultado y una del 96 % en la especie. Conclusiones. Los indicadores de competencia de la red local y de desempeño de los laboratorios intermedios alcanzaron altos estándares de calidad acordes con el proceso de entrenamiento implementado en el país.

Abstract Introduction: To reach the goal of malaria elimination in Ecuador for the year 2020, it is necessary to have a laboratory network with the capacity to perform microscopic diagnosis according to the WHO/PAHO quality standards and to provide the adequate treatment of cases. Objective: To determine the level of competence for parasitological diagnosis of the microscopists from the local public network and the performance of intermediate reference laboratories. Materials and methods: We conducted a cross-sectional study based on the information collected in workshops carried out to appraise the competence for microscopic diagnosis of the local laboratory network (zonal health coordinating offices 1 to 8) using a slide panel to evaluate diagnosis agreement, as well as the diagnostic performance of the intermediate laboratories using an external quality assessment program. The results were compared against the reference standards of the supranational laboratory in Perú. Results: We evaluated the competencies of 191 microscopists in 11 workshops and 153 (80.1%) of them were approved. The medians of the indicators were the following: concordance for parasite detection, 100% (Q1- Q3: 96-100), concordance for species identification, 100% (Q1- Q3: 93-100), and concordances for stage identification, 93.0% (Q1- Q3: 86-95) and parasite counting, 77.0% (Q1- Q3: 71-82). In the external quality assessment, the three intermediate laboratories obtained 100% in parasite detection concordance and 96% for species detection concordance. Conclusions: The results for the primary network and the performance indicators for the intermediate laboratories showed the high-quality standards of the training program implemented in the country.

[Performance assessment employing slide sets: A tool for the classification of senior microscopists from Colombia´s Malaria Control Program]. / Evaluación del desempeño mediante paneles de láminas: una herramienta para la clasificación de los microscopistas sénior del Programa de Control de la Malaria en Colombia.

INTRODUCTION: One of the most important activities for quality assurance of malaria diagnosis is performance assessment. In Colombia, performance assessment of malaria microscopists has been done through the external performance assessment and indirect external performance assessment programs. OBJECTIVES: To assess the performance of malaria microscopists of public reference laboratories using slide sets, and to describe the methodology used for this purpose. MATERIALS AND METHODS: This was a retrospective study to evaluate the concordance of senior microscopists regarding parasite detection, species identification and parasite count based on the results of the assessment of competences using two sets, one comprising 40 slides, and another one with 17 slides. RESULTS: The concordance for parasite detection was 96.9% (95% CI: 96.0-97.5) and 88.7% (95% CI: 86.6-90.5) for species identification. The average percentage of concordant slides in the group evaluated was 89.7% (95% CI: 87.5-91.6). CONCLUSIONS: Most of the senior microscopists in Colombia were classified in the two top categories in the performance assessment using slide sets. The most common difficulty encountered was the identification of parasite species. The use of this tool to assess individual performance of microscopists in the evaluation of samples with different degrees of difficulty allows for characterizing the members of the malaria diagnosis network and strengthening the abilities of those who require it.

Evaluación de campo de la precisión de la prueba de diagnóstico rápido SD Bioline Malaria Antigen Pf/Pv® en Colombia / Field evaluation for diagnostic accuracy of the rapid test SD Bioline Malaria Antigen Pf/Pv® in Colombia

Introducción. Las pruebas de diagnóstico rápido han sido postuladas como una forma de garantizar el diagnóstico de malaria, o paludismo, en zonas de difícil acceso. A pesar de su uso difundido, no hay estudios de campo que evalúen la precisión de la prueba de diagnóstico rápido SD Bioline Malaria Antigen Pf/Pv® en Colombia. Objetivo. Evaluar la precisión diagnóstica de la prueba de diagnóstico rápido SD Bioline Malaria Antigen Pf/Pv ®, en dos departamentos endémicos para malaria, comparando el diagnóstico con la gota gruesa corregida por reacción en cadena de la polimerasa (PCR). Materiales y métodos. Se trata de un estudio retrospectivo para evaluar sensibilidad, especificidad, valor diagnóstico positivo (VPP) y negativo (VPN), concordancia y límites de sensibilidad por rangos de parasitemia, de la prueba SD Bioline Malaria Antigen ® Pf/Pv, en Córdoba y Chocó. Los resultados fueron comparados con la gota gruesa corregida por PCR. Resultados. De 383 muestras procesadas, 121 fueron positivas (75 para Plasmodium vivax, 42 para P. falciparum y 4 para infección mixta) y 262 muestras negativas; los resultados obtenidos fueron los siguientes: P. vivax: sensibilidad, 92,0 % (IC 95% 83,6-96,3); especificidad, 98,7 % (IC 95% 96,7-99,5); VPP, 94,5 % (IC 95% 86,7-97,9); VPN, 98,1 % (IC 95% 95,8-99,1); IK, 0,90 (0,80-1,00). P. falciparum: sensibilidad, 88,1 % (IC 95% 75,0-94,8); especificidad, 97,9 % (IC 95% 95,8-99,0); VPP, 84,1% % (IC 95% 70,6-92,1); VPN, 98,5 % (IC 95% 96,6-99,4); IK, 0,80 (0,70-0,90). Conclusiones. La prueba tuvo un buen desempeño, siendo mejor para P. vivax en comparación con que para P. falciparum. Persisten dificultades en la detección de bajas parasitemias. La falta de amplificación de los genes Pfhrp2 y Pfhrp3 en dos muestras con diagnóstico de como infección mixta, sugiere una posible deleción conjunta de estos genes.

Introduction: Rapid diagnostic tests (RDT) have been postulated as a way to ensure access to malaria diagnosis in remote areas. Despite its widespread use, there are no field studies to evaluate the accuracy of the SD Bioline Malaria Antigen Pf/Pv in Colombia RDT. Objective: To evaluate the diagnostic accuracy of the SD Bioline Malaria Antigen Pf/Pv® RDT in two departments endemic for malaria, comparing diagnosis with thick film corrected with PCR. Materials and methods: A retrospective study was carried out to evaluate sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), concordance and sensitivity limits according to parasitemia ranges for the SD Bioline Malaria Antigen Pf/Pv ® test in Cordoba and Choco. The results were compared with microscopy corrected by PCR. Results: A total of 383 samples processed, 121 were positive (75 for P. vivax , 42 for P. falciparum and 4 for mixed infection) and 262 negative samples. P. vivax: sensitivity 92.0% (95% CI: 83.6-96.3), specificity 98.7% ( 95% CI: 96.7-99.5), PPV 94.5% (95% CI: 86.7-97.9), NPV 98.1% (95% CI: 95.8-99.1), Cohen´s kappa coefficient was 0.90 (0.80-1.00). P. falciparum: sensitivity 88.1% (95% CI: 75.0-94.8), specificity 97.9% (95% CI: 95.8-99.0), PPV 84.1% (95% CI: 70.6-92.1), NPV 98.5% (95% IC: 96.6-99.4), Cohen´s kappa coefficient 0.80 (95% CI: 0.70-0.90). Conclusions: The test performed well, being better for P. vivax as compared to P. falciparum. There are still difficulties of RDT to detect low parasitemias. The non amplification of Pfhrp2 and Pfhrp3 genes in two samples diagnosed as mixed infection, suggest a possible deletion of these two genes together.

[Field evaluation for diagnostic accuracy of the rapid test SD Bioline Malaria Antigen Pf/Pv® in Colombia]. / Evaluación de campo de la precisión de la prueba de diagnóstico rápido SD Bioline Malaria Antigen Pf/Pv® en Colombia.

INTRODUCTION: Rapid diagnostic tests (RDT) have been postulated as a way to ensure access to malaria diagnosis in remote areas. Despite its widespread use, there are no field studies to evaluate the accuracy of the SD Bioline Malaria Antigen Pf/Pv in Colombia RDT. OBJECTIVE: To evaluate the diagnostic accuracy of the SD Bioline Malaria Antigen Pf/Pv® RDT in two departments endemic for malaria, comparing diagnosis with thick film corrected with PCR. MATERIALS AND METHODS: A retrospective study was carried out to evaluate sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), concordance and sensitivity limits according to parasitemia ranges for the SD Bioline Malaria Antigen Pf/Pv ® test in Cordoba and Choco. The results were compared with microscopy corrected by PCR. RESULTS: A total of 383 samples processed, 121 were positive (75 for P. vivax , 42 for P. falciparum and 4 for mixed infection) and 262 negative samples. P. vivax: sensitivity 92.0% (95% CI: 83.6-96.3), specificity 98.7% ( 95% CI: 96.7-99.5), PPV 94.5% (95% CI: 86.7-97.9), NPV 98.1% (95% CI: 95.8-99.1), Cohen's kappa coefficient was 0.90 (0.80-1.00). P. falciparum: sensitivity 88.1% (95% CI: 75.0-94.8), specificity 97.9% (95% CI: 95.8-99.0), PPV 84.1% (95% CI: 70.6-92.1), NPV 98.5% (95% IC: 96.6-99.4), Cohen's kappa coefficient 0.80 (95% CI: 0.70-0.90). CONCLUSIONS: The test performed well, being better for P. vivax as compared to P. falciparum. There are still difficulties of RDT to detect low parasitemias. The non amplification of Pfhrp2 and Pfhrp3 genes in two samples diagnosed as mixed infection, suggest a possible deletion of these two genes together.

[Characterization of the national malaria diagnostic network, Colombia, 2006-2010]. / Caracterización de la Red Nacional de Diagnóstico de Malaria, Colombia, 2006-2010.

INTRODUCTION: The implementation and development of activities of the quality assurance system of malaria diagnosis, allows the adequate operation of the national diagnostic network, needed to strengthen prevention and control actions of this important public health problem. OBJECTIVE: To characterize the malaria diagnosis network in Colombia between 2006 and 2010. MATERIALS AND METHODS: A retrospective study was made by reviewing the annual reports of malaria diagnosis network activities that were sent by the Public Health Laboratories (PHL) between 2006 and 2010. The study included analysis of diagnostic coverage in population at risk and an evaluation of activities and training to the people responsible for malaria diagnosis. RESULTS: Malaria diagnostic coverage has increased in Colombia, from 53% of municipalities covered in 2006 to 80% in 2010. The number of places that perform diagnosis increased by 31% with a significant increase, for the same period, of the number of microscopists (56%) and laboratories (30%), to 1,195 and 1,780 respectively, registered in 2010. During the period of study, the percentage of PHL that carried out at least 3 of the activities of the quality assurance system for the diagnostic network at local level was 67%. CONCLUSIONS: It is necessary to continue strengthening the malaria diagnosis network to provide timely and adequate diagnosis in order to reduce the morbidity and mortality by malaria.

Caracterización de la Red Nacional de Diagnóstico de Malaria, Colombia, 2006-2010 / Characterization of the National Malaria Diagnostic Network, Colombia, 2006-2010

Introducción. La implementación y desarrollo de actividades del sistema de gestión de la calidad del diagnóstico de malaria, permiten el adecuado funcionamiento de la red nacional de diagnóstico, necesario para fortalecer acciones de prevención y control de este evento, importante en salud pública. Objetivo. Caracterizar la Red de Diagnóstico de Malaria en Colombia, entre 2006 y 2010. Materiales y métodos. Se hizo un estudio retrospectivo mediante la revisión de los informes anuales de actividades de la Red de Diagnóstico de Malaria, enviados por los laboratorios de salud pública entre 2006 y 2010. Se analizó la cobertura de diagnóstico en la población en riesgo, las actividades de evaluación del desempeño y las capacitaciones al personal que hace el diagnóstico. Resultados. La cobertura del diagnóstico de malaria se ha incrementado en el país, pasando de 53 % de los municipios, en 2006, a 80 %, en 2010. El número de sitios que hacen el diagnóstico aumentó en 31 %, con un incremento en el número de microscopistas (56 %) y de laboratorios (30 %), para un total de 1.195 y 1.780, respectivamente, registrados en 2010. En el periodo de estudio, se mantuvo el porcentaje de laboratorios de salud pública (67 %) que llevan a cabo, al menos, tres de las actividades del sistema de gestión de la calidad a la Red de Diagnóstico de Malaria a nivel local. Conclusiones. Es necesario continuar con el fortalecimiento de la Red de Diagnóstico de Malaria, para brindar diagnóstico oportuno y con calidad con el fin de reducir la morbimortalidad por esta causa.

Introduction. The implementation and development of activities of the quality assurance system of malaria diagnosis, allows the adequate operation of the national diagnostic network, needed to strengthen prevention and control actions of this important public health problem. Objective. To characterize the malaria diagnosis network in Colombia between 2006 and 2010. Materials and methods. A retrospective study was made by reviewing the annual reports of malaria diagnosis network activities that were sent by the Public Health Laboratories (PHL) between 2006 and 2010. The study included analysis of diagnostic coverage in population at risk and an evaluation of activities and training to the people responsible for malaria diagnosis. Results. Malaria diagnostic coverage has increased in Colombia, from 53% of municipalities covered in 2006 to 80% in 2010. The number of places that perform diagnosis increased by 31% with a significant increase, for the same period, of the number of microscopists (56%) and laboratories (30%), to 1,195 and 1,780 respectively, registered in 2010. During the period of study, the percentage of PHL that carried out at least 3 of the activities of the quality assurance system for the diagnostic network at local level was 67%. Conclusions. It is necessary to continue strengthening the malaria diagnosis network to provide timely and adequate diagnosis in order to reduce the morbidity and mortality by malaria.

[Evaluation of rapid diagnostic tests for malaria in Colombia as an integral part of the disease control strategy]. / Evaluación de la aplicación de pruebas de diagnóstico rápido para malaria como parte de una estrategia integral para su control en Colombia.

INTRODUCTION: The Andean Health Organization has been responsible for the coordination and evaluation of the malaria rapid diagnostic test strategy. This undertaking was organized to strengthen the malaria diagnostic capacity in ten provinces of Colombia. OBJECTIVE: The implementation cycle of malaria rapid diagnostic tests was evaluated, along with its impact, performance, usage and coverage under the project "Malaria control in bordering areas of the Andean Region: a community cpproach" (PAMAFRO), as an integral part of the malaria control strategy. MATERIALS AND METHODS: A descriptive retrospective study was organized in two stages. The first stage was an evaluation of the implementation of the rapid diagnostic test cycle. The second stage evaluated indicators of impact, performance, usage and coverage of this strategy. These evaluations were conducted from October 2007 to July 2008 in 10 Andean provinces of Colombia. A multi-criteria scoring method was applied to determine the critical variables. RESULTS: The compliance in the implementation cycle for rapid diagnostic tests was 71%. Planning was the weakest component of the cycle with 50% of the goals accomplished. The critical variables with low compliance were as follows: study of rapid diagnostic test needs in the country (50%), study of rapid diagnostic test needs in each province (50%), rapid diagnostic test distribution according to needs (50%), assessment of health workers performance (50%), compliance with temperature and humidity requirements for storage of the rapid diagnostic tests at the provincial level (50%), logistics (67%) and supervision (25%). CONCLUSION: Implementation strategies are important to strengthen the critical variables found asociated with low compliance.

Evaluación de la aplicación de pruebas de diagnóstico rápido para malaria como parte de una estrategia integral para su control en Colombia / Evaluation of rapid diagnostic tests for malaria in Colombia as an integral part of the disease control strategy

Introducción. El Organismo Andino de la Salud coordinó y evaluó la estrategia de aplicación de pruebas de diagnóstico rápido de malaria para fortalecer el diagnóstico de esta enfermedad en diez departamentos de Colombia. Objetivo. Evaluar el ciclo de implementación, impacto, resultado, uso y cobertura de la aplicación de las pruebas de diagnóstico rápido en el ámbito del proyecto Control de la malaria en zonas fronterizas de la Región Andina: un enfoque comunitario (PAMAFRO), como parte de una estrategia integral para el control de la malaria. Materiales y métodos. En un estudio descriptivo retrospectivo, se evaluó el ciclo de implementación del uso de las pruebas de diagnóstico rápido, primera etapa, y los indicadores de resultado, uso y cobertura de la estrategia, segunda etapa, durante el periodo de octubre de 2007 a julio de 2008. Se aplicó el análisis multicriterio, método de puntaje para determinar las variables críticas. Resultados. El cumplimiento del ciclo de implementación fue de 71 %, y la planeación fue el componente más débil del ciclo, con un cumplimiento del 50 %. Se determinaron como variables críticas y con bajo cumplimiento las siguientes: estudio de las necesidades de pruebas de diagnóstico rápido en el país (50 %), estudio de necesidades en los departamentos (50 %), distribución de las pruebas según las necesidades (50 %), evaluación del desempeño de los trabajadores de salud (50 %), cumplimiento de directrices sobre temperatura y humedad de las pruebas en el nivel departamental (50 %), logística (50 %) y supervisión (25 %). Conclusiones. Es importante que en futuras estrategias de aplicación de pruebas de diagnóstico rápido en el país, se fortalezcan las variables críticas de bajo cumplimiento encontradas en el presente estudio.

Introduction. The Andean Health Organization has been responsible for the coordination and evaluation of the malaria rapid diagnostic test strategy. This undertaking was organized to strengthen the malaria diagnostic capacity in ten provinces of Colombia. Objective. The implementation cycle of malaria rapid diagnostic tests was evaluated, along with its impact, performance, usage and coverage under the project “Malaria control in bordering areas of the Andean Region: a community cpproach (PAMAFRO), as an integral part of the malaria control strategy. Materials and methods. A descriptive retrospective study was organized in two stages. The first stage was an evaluation of the implementation of the rapid diagnostic test cycle. The second stage evaluated indicators of impact, performance, usage and coverage of this strategy. These evaluations were conducted from October 2007 to July 2008 in 10 Andean provinces of Colombia. A multi-criteria scoring method was applied to determine the critical variables. Results. The compliance in the implementation cycle for rapid diagnostic tests was 71%. Planning was the weakest component of the cycle with 50% of the goals accomplished. The critical variables with low compliance were as follows: study of rapid diagnostic test needs in the country (50%), study of rapid diagnostic test needs in each province (50%), rapid diagnostic test distribution according to needs (50%), assessment of health workers performance (50%), compliance with temperature and humidity requirements for storage of the rapid diagnostic tests at the provincial level (50%), logistics (67%) and supervision (25%). Conclusion. Implementation strategies are important to strengthen the critical variables found asociated with low compliance.

Evaluación de dos pruebas rápidas [NOW® ICT Malaria Pf/Pv y OptiMAL®] para el diagnóstico de paludismo en Tumaco, Colombia / Evaluation of two rapid diagnostic tests, NOW® ICT Malaria Pf/Pv and OptiMAL®, for diagnosis of malaria

Introducción. El Instituto Nacional de Salud con el fin de mejorar el acceso al diagnóstico de paludismo, evaluó dos pruebas rápidas para el diagnóstico de dicha enfermedad. Objetivo. Evaluar la sensibilidad, especificidad y concordancia de dos pruebas inmunocromatográficas, NOW® ICT Malaria Pf/Pv y OptiMAL®, frente a la gota gruesa. Materiales y métodos. Se llevó a cabo un estudio descriptivo de concordancia en 214 pacientes de Tumaco, captados mediante búsqueda pasiva y brigadas de atención, que presentaran, por lo menos, uno de los síntomas de la tríada clásica. Resultados. NOW® ICT tuvo una sensibilidad general de 98,4 por ciento (intervalo de confianza de 95 por ciento (IC95 por ciento): 90,3-99,9), especificidad general de 98,0 por ciento (IC95 por ciento: 93,9-99,5). Para Plasmodium falciparum la sensibilidad fue de 98,2 por ciento (IC95 por ciento: 89,4-99,9) especificidad de 98,1 por ciento (IC95 por ciento: 94,1-99,5). Esta sensibilidad disminuyó a 80 por ciento en el rango de 200-4.000 parásitos/µl. Los valores de sensibilidad y especificidad de NOW® ICT para Plasmodium vivax fueron del 100 por ciento y no se afectó la sensibilidad en los rangos de parasitemias establecidos. OptiMAL® tuvo una sensibilidad general de 95,2 por ciento (IC95 por ciento: 85,8-98,8) y especificidad general de 99,3 por ciento (IC95 por ciento: 95,8-100,0). Para P. falciparum OptiMAL® tuvo una sensibilidad de 94,7 por ciento (IC95 por ciento: 84,5-98,6) y especificidad de 99,4 por ciento (IC95 por ciento: 96,0-100,0). La sensibilidad disminuyó a 60 por ciento en el rango de de 200-4.000 parásitos/µl. La sensibilidad de OptiMAL® para P. vivax fue 66,7 por ciento (IC95 por ciento: 24,1-94,0), pero disminuyó a 50 por ciento en el rango de 300-2.500 parásitos/µl. Conclusiones. Se obtuvieron buenos resultados en la sensibilidad y la especificidad para ambas pruebas, pero superiores para NOW® ICT.

Introduction. To increase the accessibility of malaria diagnosis, the Instituto Nacional de Salud de Colombia undertook a field trial to evaluate the sensitivity and specificity of two rapid diagnostic tests. Objective. The sensitivity, specificity and concordance was compared for two rapid diagnostic tests for malaria, NOW® ICT Malaria Pf/Pv and OptiMAL®, Materials and methods. A descriptive and concordance study was performed with 214 patients in the southwestern coastal city of Tumaco, Colombia, each of whom presented at least one of the symptoms of the classical malaria triad. Two strategies were applied for patient recruitment—one by passive search and a second through local health brigades. Results. NOW® ICT showed a general sensitivity of 98.4% (95%CI: 90.3-99.9), and a general specificity of 98.0% (95%CI: 93.9-99.5). For Plasmodium falciparum, the sensitivity was 98.2% (95%CI: 89.4-99.9) and the specificity 98.1% (95%CI: 94.1-99.5). The sensitivity was lower (80.0%) when parasitemia ranged from 200 to 4,000 parasites/ ìl. The sensitivity and specificity of the NOW® ICT for P. vivax malaria were 100%. The sensitivity for this test was not affected for the established ranges of parasitemia for P. vivax. The overall figures for OptiMAL® were 95.2% (95%CI: 85.8-98.8) sensitivity and 99.3% (95%CI: 95.8-100.0) specificity. For P. falciparum malaria OptiMAL® showed 94.7% (95%CI: 84.5-98.6) sensitivity and 99.4% (95%CI: 96.0-100.0) specificity. The sensitivity was lower (60.0%) when samples with 200-4,000 parasites/ìl were tested. For P. vivax, OptiMAL® presented a 66.7% (95%CI: 24.1-94.0) sensitivity, which diminished to 50% with a parasitemia between 300-2.500 parasites/ ìL. Conclusions. Good results for sensitivity and specificity were obtained for malaria diagnosis using NOW® ICT and OptiMAL®, with NOW®ICT showing higher sensitivity and specificity values than OptiMAL®.

[Evaluation of two rapid diagnostic tests, NOW ICT Malaria Pf/Pv and OptiMAL, for diagnosis of malaria]. / Evaluación de dos pruebas rápidas [NOW ICT Malaria Pf/Pv y OptiMAL] para el diagnóstico de paludismo en Tumaco, Colombia.

INTRODUCTION: To increase the accessibility of malaria diagnosis, the Instituto Nacional de Salud de Colombia undertook a field trial to evaluate the sensitivity and specificity of two rapid diagnostic tests. OBJECTIVE: The sensitivity, specificity and concordance was compared for two rapid diagnostic tests for malaria, NOW ICT Malaria Pf/Pv and OptiMAL. MATERIALS AND METHODS: A descriptive and concordance study was performed with 214 patients in the southwestern coastal city of Tumaco, Colombia, each of whom presented at least one of the symptoms of the classical malaria triad. Two strategies were applied for patient recruitment-one by passive search and a second through local health brigades. RESULTS: NOW ICT showed a general sensitivity of 98.4% (95%CI: 90.3-99.9), and a general specificity of 98.0% (95%CI: 93.9-99.5). For Plasmodium falciparum, the sensitivity was 98.2% (95%CI: 89.4-99.9) and the specificity 98.1% (95%CI: 94.1-99.5). The sensitivity was lower (80.0%) when parasitemia ranged from 200 to 4,000 parasites/microl. The sensitivity and specificity of the NOW ICT for P. vivax malaria were 100%. The sensitivity for this test was not affected for the established ranges of parasitemia for P. vivax. The overall figures for OptiMAL were 95.2% (95%CI: 85.8-98.8) sensitivity and 99.3% (95%CI: 95.8-100.0) specificity. For P. falciparum malaria OptiMAL showed 94.7% (95%CI: 84.5-98.6) sensitivity and 99.4% (95%CI: 96.0-100.0) specificity. The sensitivity was lower (60.0%) when samples with 200-4,000 parasites/microl were tested. For P. vivax, OptiMAL presented a 66.7% (95%CI: 24.1-94.0) sensitivity, which diminished to 50% with a parasitemia between 300-2.500 parasites/microL. CONCLUSIONS: Good results for sensitivity and specificity were obtained for malaria diagnosis using NOW ICT and OptiMAL, with NOW ICT showing higher sensitivity and specificity values than OptiMAL.