Statistical implicative analysis for educational data sets: 2 analysis with RCHIC

[ES]En este trabajo mediante dos ejemplos mostramos nuestro interés en la utilización del Análisis Estadístico Implicativo (SIA) en la comprensión de relaciones entre datos en Educación. Con SIA y la herramienta RCHIC es posible construir, gráficos (árbol de jerarquía, grafo implicativo) en los cuales el profesor o experto pueden visualizar y comprender las implicaciones entre los datos. Recomendamos a los profesores e instituciones utilizar SIA, debido a que ésta es una herramienta que permite encontrar posibles soluciones para mejorar evaluaciones, encuestas, etc

G6PD Deficiency at Sumba in Eastern Indonesia Is Prevalent, Diverse and Severe: Implications for Primaquine Therapy against Relapsing Vivax Malaria

Safe treatment of Plasmodium vivax requires diagnosis of both the infection and status of erythrocytic glucose-6-phosphate dehydrogenase (G6PD) activity because hypnozoitocidal therapy against relapse requires primaquine, which causes a mild to severe acute hemolytic anemia in G6PD deficient patients. Many national malaria control programs recommend primaquine therapy without G6PD screening but with monitoring due to a broad lack of G6PD deficiency screening capacity. The degree of risk in doing so hinges upon the level of residual G6PD activity among the variants present in any given area. We conducted studies on Sumba Island in eastern Indonesia in order to assess the potential threat posed by primaquine therapy without G6PD screening. We sampled 2,033 residents of three separate districts in western Sumba for quantitative G6PD activity and 104 (5.1%) were phenotypically deficient (\u3c4.6U/gHb; median normal 10U/gHb). The villages were in two distinct ecosystems, coastal and inland. A positive correlation occurred between the prevalence of malaria and G6PD deficiency: 5.9% coastal versus inland 0.2% for malaria (P\u3c0.001), and 6.7% and 3.1% for G6PD deficiency (P\u3c0.001) at coastal and inland sites, respectively. The dominant genotypes of G6PD deficiency were Vanua Lava, Viangchan, and Chatham, accounting for 98.5%of the 70 samples genotyped. Subjects expressing the dominant genotypes all had less than 10% of normal enzyme activities and were thus considered severe variants. Blind administration of anti-relapse primaquine therapy at Sumba would likely impose risk of serious harm

Hypnozoite depletion in successive Plasmodium vivax relapses

Genotyping Plasmodium vivax relapses can provide insights into hypnozoite biology. We performed targeted amplicon sequencing of 127 relapses occurring in Indonesian soldiers returning to malaria-free Java after yearlong deployment in malarious Eastern Indonesia. Hepatic carriage of multiple hypnozoite clones was evident in three-quarters of soldiers with two successive relapses, yet the majority of relapse episodes only displayed one clonal population. The number of clones detected in relapse episodes decreased over time and through successive relapses, especially in individuals who received hypnozoiticidal therapy. Interrogating the multiplicity of infection in this P. vivax relapse cohort reveals evidence of independent activation and slow depletion of hypnozoites over many months by multiple possible mechanisms, including parasite senescence and host immunity

Genetic micro-epidemiology of malaria in Papua Indonesia: Extensive P. vivax diversity and a distinct subpopulation of asymptomatic P. falciparum infections

Background: Genetic analyses of Plasmodium have potential to inform on transmission dynamics, but few studies have evaluated this on a local spatial scale. We used microsatellite genotyping to characterise the micro-epidemiology of P. vivax and P. falciparum diversity to inform malaria control strategies in Timika, Papua Indonesia. Methods: Genotyping was undertaken on 713 sympatric P. falciparum and P. vivax isolates from a cross-sectional household survey and clinical studies conducted in Timika. Standard population genetic measures were applied, and the data was compared to published data from Kalimantan, Bangka, Sumba and West Timor. Results: Higher diversity (HE = 0.847 vs 0.625; p = 0.017) and polyclonality (46.2% vs 16.5%, p&lt;0.001) were observed in P. vivax versus P. falciparum. Distinct P. falciparum substructure was observed, with two subpopulations, K1 and K2. K1 was comprised solely of asymptomatic infections and displayed greater relatedness to isolates from Sumba than to K2, possibly reflecting imported infections. Conclusions: The results demonstrate the greater refractoriness of P. vivax versus P. falciparum to control measures, and risk of distinct parasite subpopulations persisting in the community undetected by passive surveillance. These findings highlight the need for complimentary new surveillance strategies to identify transmission patterns that cannot be detected with traditional malariometric methods.</p

Genetic micro-epidemiology of malaria in Papua Indonesia: Extensive P. vivax diversity and a distinct subpopulation of asymptomatic P. falciparum infections

BACKGROUND:Genetic analyses of Plasmodium have potential to inform on transmission dynamics, but few studies have evaluated this on a local spatial scale. We used microsatellite genotyping to characterise the micro-epidemiology of P. vivax and P. falciparum diversity to inform malaria control strategies in Timika, Papua Indonesia. METHODS:Genotyping was undertaken on 713 sympatric P. falciparum and P. vivax isolates from a cross-sectional household survey and clinical studies conducted in Timika. Standard population genetic measures were applied, and the data was compared to published data from Kalimantan, Bangka, Sumba and West Timor. RESULTS:Higher diversity (HE = 0.847 vs 0.625; p = 0.017) and polyclonality (46.2% vs 16.5%, p<0.001) were observed in P. vivax versus P. falciparum. Distinct P. falciparum substructure was observed, with two subpopulations, K1 and K2. K1 was comprised solely of asymptomatic infections and displayed greater relatedness to isolates from Sumba than to K2, possibly reflecting imported infections. CONCLUSIONS:The results demonstrate the greater refractoriness of P. vivax versus P. falciparum to control measures, and risk of distinct parasite subpopulations persisting in the community undetected by passive surveillance. These findings highlight the need for complimentary new surveillance strategies to identify transmission patterns that cannot be detected with traditional malariometric methods

Genetic micro-epidemiology of malaria in Papua Indonesia: Extensive <i>P</i>. <i>vivax</i> diversity and a distinct subpopulation of asymptomatic <i>P</i>. <i>falciparum</i> infections

<div><p>Background</p><p>Genetic analyses of <i>Plasmodium</i> have potential to inform on transmission dynamics, but few studies have evaluated this on a local spatial scale. We used microsatellite genotyping to characterise the micro-epidemiology of <i>P</i>. <i>vivax</i> and <i>P</i>. <i>falciparum</i> diversity to inform malaria control strategies in Timika, Papua Indonesia.</p><p>Methods</p><p>Genotyping was undertaken on 713 sympatric <i>P</i>. <i>falciparum</i> and <i>P</i>. <i>vivax</i> isolates from a cross-sectional household survey and clinical studies conducted in Timika. Standard population genetic measures were applied, and the data was compared to published data from Kalimantan, Bangka, Sumba and West Timor.</p><p>Results</p><p>Higher diversity (<i>H</i>_<i>E</i> = 0.847 vs 0.625; <i>p</i> = 0.017) and polyclonality (46.2% vs 16.5%, <i>p</i><0.001) were observed in <i>P</i>. <i>vivax</i> versus <i>P</i>. <i>falciparum</i>. Distinct <i>P</i>. <i>falciparum</i> substructure was observed, with two subpopulations, K1 and K2. K1 was comprised solely of asymptomatic infections and displayed greater relatedness to isolates from Sumba than to K2, possibly reflecting imported infections.</p><p>Conclusions</p><p>The results demonstrate the greater refractoriness of <i>P</i>. <i>vivax</i> versus <i>P</i>. <i>falciparum</i> to control measures, and risk of distinct parasite subpopulations persisting in the community undetected by passive surveillance. These findings highlight the need for complimentary new surveillance strategies to identify transmission patterns that cannot be detected with traditional malariometric methods.</p></div

Laboratory challenges of Plasmodium species identification in Aceh Province, Indonesia, a malaria elimination setting with newly discovered P. knowlesi.

The discovery of the life-threatening zoonotic infection Plasmodium knowlesi has added to the challenges of prompt and accurate malaria diagnosis and surveillance. In this study from Aceh Province, Indonesia, a malaria elimination setting where P. knowlesi endemicity was not previously known, we report the laboratory investigation and difficulties encountered when using molecular detection methods for quality assurance of microscopically identified clinical cases. From 2014 to 2015, 20 (49%) P. falciparum, 16 (39%) P. vivax, 3 (7%) P. malariae, and 2 (5%) indeterminate species were identified by microscopy from four sentinel health facilities. At a provincial-level reference laboratory, loop-mediated isothermal amplification (LAMP), a field-friendly molecular method, was performed and confirmed Plasmodium in all samples though further species-identification was limited by the unavailability of non-falciparum species-specific testing with the platform used. At a national reference laboratory, several molecular methods including nested PCR (nPCR) targeting the 18 small sub-unit (18S) ribosomal RNA, nPCR targeting the cytochrome-b (cytb) gene, a P. knowlesi-specific nPCR, and finally sequencing, were necessary to ultimately classify the samples as: 19 (46%) P. knowlesi, 8 (20%) P. falciparum, 14 (34%) P. vivax. Microscopy was unable to identify or mis-classified up to 56% of confirmed cases, including all cases of P. knowlesi. With the nPCR methods targeting the four human-only species, P. knowlesi was missed (18S rRNA method) or showed cross-reactivity for P. vivax (cytb method). To facilitate diagnosis and management of potentially fatal P. knowlesi infection and surveillance for elimination of human-only malaria in Indonesia and other affected settings, new detection methods are needed for testing at the point-of-care and in local reference laboratories

Demographic, malaria and G6PDd prevalence data by gender and ecosystem in western Sumba.

<p>n = sample number.</p><p>¹ Population number was obtained from central agency statistic from each district.</p><p>² Microscopy diagnosed.</p><p>³ One subject experienced mixed infection of <i>P</i>. <i>falciparum</i> and <i>P</i>. <i>vivax</i>.</p><p>⁴ Hb < 10 g/dl.</p><p>⁵ G6PD activities ≤4.6 U/gHb.</p><p>⁶ Samples screened as G6PD deficient but declined, absent or failed to be DNA extracted.</p><p>Demographic, malaria and G6PDd prevalence data by gender and ecosystem in western Sumba.</p

Impact of Hb level on G6PD activities.

<p>Blue line represents those samples having extremely high G6PD activity and some degree of anemia (R² = 0.08) and red line represents those having normal Hb level (R² = 0.48) and t-value = 28.6 (p<0.001).</p