Therapeutic response to four artemisinin-based combination therapies in Angola, 2021.

Monitoring antimalarial efficacy is important to detect the emergence of parasite drug resistance. Angola conducts in vivo therapeutic efficacy studies (TESs) every 2 years in its fixed sentinel sites in Benguela, Lunda Sul, and Zaire provinces. Children with uncomplicated Plasmodium falciparum malaria were treated with artemether-lumefantrine (AL), artesunate-amodiaquine (ASAQ), dihydroartemisinin-piperaquine (DP), or artesunate-pyronaridine (ASPY) and followed for 28 (AL and ASAQ) or 42 days (DP and ASPY) to assess clinical and parasitological response to treatment. Two drugs were sequentially assessed in each site in February-July 2021. The primary indicator was the Kaplan-Meier estimate of the PCR-corrected efficacy at the end of the follow-up period. A total of 622 patients were enrolled in the study and 590 (95%) participants reached a study endpoint. By day 3, ≥98% of participants were slide-negative in all study sites and arms. After PCR correction, day 28 AL efficacy was 88.0% (95% CI: 82%-95%) in Zaire and 94.7% (95% CI: 90%-99%) in Lunda Sul. For ASAQ, day 28 efficacy was 92.0% (95% CI: 87%-98%) in Zaire and 100% in Lunda Sul. Corrected day 42 efficacy was 99.6% (95% CI: 99%-100%) for ASPY and 98.3% (95% CI: 96%-100%) for DP in Benguela. High day 3 clearance rates suggest no clinical evidence of artemisinin resistance. This was the fourth of five rounds of TES in Angola showing a corrected AL efficacy <90% in a site. For Zaire, AL has had an efficacy <90% in 2013, 2015, and 2021. ASAQ, DP, and ASPY are appropriate choices as artemisinin-based combination therapies in Angola.

Continued Low Efficacy of Artemether-Lumefantrine in Angola in 2019.

Biennial therapeutic efficacy monitoring is a crucial activity for ensuring the efficacy of currently used artemisinin-based combination therapy in Angola. Children with acute uncomplicated Plasmodium falciparum infection in sentinel sites in the Benguela, Zaire, and Lunda Sul Provinces were treated with artemether-lumefantrine (AL) or artesunate-amodiaquine (ASAQ) and monitored for 28 days to assess clinical and parasitological responses. Molecular correction was performed using seven microsatellite markers. Samples from treatment failures were genotyped for the pfk13, pfcrt, and pfmdr1 genes. Day 3 clearance rates were ≥95% in all arms. Uncorrected day 28 Kaplan-Meier efficacy estimates ranged from 84.2 to 90.1% for the AL arms and 84.7 to 100% for the ASAQ arms. Corrected day 28 estimates were 87.6% (95% confidence interval [CI], 81 to 95%) for the AL arm in Lunda Sul, 92.2% (95% CI, 87 to 98%) for AL in Zaire, 95.6% (95% CI, 91 to 100%) for ASAQ in Zaire, 98.4% (95% CI, 96 to 100%) for AL in Benguela, and 100% for ASAQ in Benguela and Lunda Sul. All 103 analyzed samples had wild-type pfk13 sequences. The 76T pfcrt allele was found in most (92%; 11/12) ASAQ late-failure samples but in only 16% (4/25) of AL failure samples. The N86 pfmdr1 allele was found in 97% (34/35) of treatment failures. The AL efficacy in Lunda Sul was below the 90% World Health Organization threshold, the third time in four rounds that this threshold was crossed for an AL arm in Angola. In contrast, the observed ASAQ efficacy has not been below 95% to date in Angola, including this latest round.

Lack of knowledge regarding the microscopic diagnosis of malaria by technicians of the laboratory network in Luanda, Angola.

INTRODUCTION: Malaria is still one of the most important public health problems worldwide. The diagnosis of this disease is still mainly based on thick blood films.  OBJECTIVE: To evaluate the knowledge about malaria diagnosis of the technicians of the public health network in Luanda, Angola, by means of a survey.  MATERIALS AND METHODS: This survey was carried out in three phases. In the first one, open interviews were done to technicians related with the different procedures for malaria diagnosis. In the second one, a preliminary questionnaire was prepared and evaluated. In the third phase, a definitive questionnaire was applied to 120 technicians from Luanda between April and July, 2013. The proportions of correct and incorrect answers were compared for every question of the survey.  RESULTS: Significantly higher proportions of incorrect answers (p<0.05) were found in the questions related to clinical manifestations, 68/52 (p<0.05), species of Plasmodium according to geographical areas, 76/44 (p<0.05), the type of granulations according to species, 96/24 (p<0.01), the class of microscope magnifying glasses used to observe the thick smear, 105/15 (p<0.01), the thick smear report, 76/44 (p<0.01), the time and preparation of different stain solutions, 81/39 (p<0.01), and the number of parasites counted per 200 leukocytes, 96/24 (p<0.01).  CONCLUSIONS: Various failures for the microscopic diagnosis of malaria were observed amongst the evaluated technicians. These results will be useful as a baseline study before applying an educational intervention aimed to improve the quality of malaria diagnosis in Luanda's laboratory network.

La insuficiencia de conocimientos para el diagnóstico microscópico de la malaria en técnicos de la red de laboratorios de Luanda, Angola / Lack of knowledge regarding the microscopic diagnosis of malaria by technicians of the laboratory network in Luanda, Angola

Introducción. La malaria, o paludismo, continúa siendo uno de los más importantes problemas de salud pública a nivel mundial. La gota gruesa sigue siendo la técnica de referencia para su diagnóstico. Objetivo. Evaluar los conocimientos para el diagnóstico de la malaria de técnicos del sector de la salud en Luanda, Angola, mediante una encuesta. Materiales y métodos. La preparación de la encuesta transcurrió en tres etapas: primero, se hicieron entrevistas abiertas a los técnicos en torno a los diferentes procedimientos para el diagnóstico microscópico de la malaria; en una segunda etapa, se preparó el cuestionario preliminar, y en la tercera, se elaboró el cuestionario definitivo. La encuesta se hizo en un grupo de 120 técnicos de la red nacional de salud entre los meses de abril y julio de 2013. Se comparó la proporción de respuestas correctas e incorrectas considerando como significativo un valor de p<0,05. Resultados. Las respuestas incorrectas predominaron sobre las correctas, de forma estadísticamente significativa (p<0,05), en las preguntas sobre: las manifestaciones clínicas (68 Vs . 52); las especies de Plasmodium según zonas geográficas (76 Vs . 44); el tipo de granulaciones según la especie parasitaria (96 Vs . 24); el tipo de lente para visualizar la gota gruesa (105 Vs . 15); la forma de hacer un informe del resultado de la microscopía (76 Vs . 44); el tiempo y la concentración de las diferentes soluciones que se utilizan (81 Vs . 39), y el número de parásitos por 200 leucocitos (96 Vs . 24). Conclusiones. Se demostró la insuficiencia de conocimientos para el diagnóstico microscópico de la malaria. Estos resultados servirán de base para el desarrollo de las herramientas de una intervención educativa orientada a mejorar la calidad del diagnóstico de la malaria en la red de laboratorios de Luanda.

Introduction: Malaria is still one of the most important public health problems worldwide. The diagnosis of this disease is still mainly based on thick blood films. Objective: To evaluate the knowledge about malaria diagnosis of the technicians of the public health network in Luanda, Angola, by means of a survey. Methods: This survey was carried out in three phases. In the first one, open interviews were done to technicians related with the different procedures for malaria diagnosis. In the second one, a preliminary questionnaire was prepared and evaluated. In the third phase, a definitive questionnaire was applied to 120 technicians from Luanda between April and July, 2013. The proportions of correct and incorrect answers were compared for every question of the survey. Results: Significantly higher proportions of incorrect answers (p<0.05) were found in the questions related to clinical manifestations, 68/52 (p<0.05), species of Plasmodium according to geographical areas, 76/44 (p<0.05), the type of granulations according to species, 96/24 (p<0.01), the class of microscope magnifying glasses used to observe the thick smear, 105/15 (p<0.01), the thick smear report, 76/44 (p<0.01), the time and preparation of different stain solutions, 81/39 (p<0.01), and the number of parasites counted per 200 leukocytes, 96/24 (p<0.01). Conclusions: Various failures for the microscopic diagnosis of malaria were observed amongst the evaluated technicians. These results will be useful as a baseline study before applying an educational intervention aimed to improve the quality of malaria diagnosis in Luanda´s laboratory network.

Evaluación de la calidad del diagnóstico de la malaria por microscopía óptica en laboratorios provinciales de la República de Angola / Evaluation of the quality of malaria diagnosis by optical microscopy in provincial laboratories of the Republic of Angola

INTRODUCCIÓN: la malaria continúa siendo uno de los más importantes problemas de la salud pública a nivel mundial y afecta severamente al continente africano. OBJETIVO: evaluar el nivel de conocimientos teóricos y prácticos en el diagnóstico de la malaria de un grupo de técnicos dedicados a esta actividad. MÉTODOS: entre los años 2010 y 2012, se realizó un estudio cuasi experimental de evaluación en la red de salud, en 14 laboratorios provinciales de las 18 provincias de la República Angola, donde se entrenaron 243 técnicos que realizan habitualmente el diagnóstico de la malaria. Se hicieron entrenamientos de 10 días (70 horas) cumplimentando un programa que incluyó clases prácticas y teóricas, y sus respectivas evaluaciones inicial y final. RESULTADOS: después de los entrenamientos en cada una de las 14 provincias evaluadas la frecuencia de los técnicos desaprobados en la evaluaciones teóricas y prácticas disminuyó significativamente, (p<0,01). CONCLUSIONES: este es el primer trabajo realizado en Angola donde se demuestra una mejoría cualitativa y cuantitativa tanto en los conocimientos teóricos y habilidades prácticas de los técnicos después de un entrenamiento y readiestramiento, y constituye el primer paso de un esfuerzo encaminado para mejorar el diagnóstico de la malaria en el país(AU)

INTRODUCTION: malaria continues to be one of the main public health problems worldwide, severely affecting the African continent. OBJECTIVE: evaluate the level of theoretical and practical competence in the diagnosis of malaria achieved by a group of technicians engaged in this activity. METHODS: an evaluative quasi-experimental study was conducted from 2010 to 2012 in 14 provincial laboratories from the 18 provinces of the Republic of Angola, where 243 technicians received training in the field of malaria diagnosis. Training extended for 10 days (70 hours) based on a syllabus which included theoretical and practical lessons as well as an initial and a final evaluation. RESULTS: a post-training evaluation conducted in 14 provinces showed a significant decrease in the number of technicians failing their theoretical and practical tests (p<0.01). CONCLUSIONS: this is the first evaluation carried out in Angola in which qualitative and quantitative improvement is observed both in the theoretical knowledge and the practical skills of technicians after receiving training or retraining. It is also a first step in an effort to improve the quality of malaria diagnosis in the country(AU)