Publications of Marie-Pierre HAYETTE
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See detailA phylodynamic workflow to rapidly gain insights into the dispersal history and dynamics of SARS-CoV-2 lineages
Dellicour, Simon; Durkin, Keith ULiege; Hong, Samuel et al

E-print/Working paper (2020)

Since the start of the COVID-19 pandemic, an unprecedented number of genomic sequences of the causative virus (SARS-CoV-2) have been publicly released. The resulting volume of available genetic data ... [more ▼]

Since the start of the COVID-19 pandemic, an unprecedented number of genomic sequences of the causative virus (SARS-CoV-2) have been publicly released. The resulting volume of available genetic data presents a unique opportunity to gain real-time insights into the pandemic, but also a daunting computational hurdle if analysed with gold-standard phylogeographic methods. We here describe and apply an analytical pipeline that is a compromise between fast and rigorous analytical steps. As a proof of concept, we focus on Belgium, one of the countries with the highest spatial density of sequenced SARS-CoV-2 genomes. At the global scale, our analyses confirm the importance of external introduction events in establishing transmission chains in the country. At the country scale, our spatially-explicit phylogeographic analyses highlight an impact of the national lockdown of mid-March on the dispersal velocity of viral lineages. Our pipeline has the potential to be quickly applied to other countries or regions, with key benefits in complementing epidemiological analyses in assessing the impact of intervention measures or their progressive easement. [less ▲]

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See detailVariability and target attainment of fluconazole in critically ill patients
Van Daele, Ruth; Wauters, Joost; Brüggemann, Roger J. et al

Poster (2020, April 21)

Background: Fluconazole is an antifungal drug frequently used in the intensive care unit (ICU) but few data are available regarding its exposure in this population. A subanalysis of the DALI-study raised ... [more ▼]

Background: Fluconazole is an antifungal drug frequently used in the intensive care unit (ICU) but few data are available regarding its exposure in this population. A subanalysis of the DALI-study raised some concerns considering variability in exposure and inadequate target attainment in critically ill patients. We aimed to determine fluconazole variability and target attainment at the ICU. Materials/methods: All adult, critically ill patients treated with intravenous fluconazole between May and September 2019 were included, provided that the DNR code was <2 and written informed consent was obtained. The administered dose was left at the discretion of the treating clinician. Trough samples were collected during a maximum period of 15 days. Samples were analysed using an UPLC-DAD analytic method. The intra-and intersubject variability of fluconazole trough concentrations was calculated by dividing the standard deviation by the mean*100. Moreover, the difference between the maximum and minimum fluconazole concentration within each patients was determined. For target attainment, the fAUC/MIC from clinical data amounts to 100 corresponding with trough levels >10-15 mg/L, as recommended by EUCAST and ECIL-6. The limit for toxicity was set on 50 mg/L. Results: Seventeen patients were included, resulting in 95 fluconazole trough levels. Patients had a median APACHE-II score of 18 [16-23] and administered dose of 5.1 [4.1-7.5] mg/kg/day. The median fluconazole trough level was 26.6 [19.7-35.3] mg/L. In Figure 1, fluconazole trough concentrations are depicted in function of the dose. The mean intra-and intersubject variability (CV%) were 18,4% and 34,5%, respectively. The median difference between the maximum and minimum concentration for the 14 patients with >1 measured fluconazole level, was 14,8 [6,6-18,9] mg/L. In two patients, this difference was more than 2-fold. All trough levels were >10mg/L and 85/95 (89%) samples were >15mg/L. None of the levels exceeded the upper limit of 50 mg/L. Conclusions: As shown in the DALI-study, a considerable intra-and intersubject variability in fluconazole levels was observed at the ICU. Despite this variability, all fluconazole trough levels were above the lower limit of 10 mg/L and most of them >15 mg/L. No toxic concentrations were observed. [less ▲]

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See detailMulticentre validation of a EUCAST method for the antifungal susceptibility testing of microconidia-forming dermatophytes
Arendrup, Maiken; Jorgensen, Karin; Guinea, Jesus et al

Poster (2020, April)

Background: Terbinafine resistance is increasingly reported in Trichophyton rubrum and Trichophyton interdigitale rendering susceptibility testing important particularly in non-responding cases. We ... [more ▼]

Background: Terbinafine resistance is increasingly reported in Trichophyton rubrum and Trichophyton interdigitale rendering susceptibility testing important particularly in non-responding cases. We performed a multicentre evaluation of a recently proposed modified EUCAST method implementing medium supplemented with chloramphenicol and cycloheximide (CC) to avoid contamination. Materials/methods: A blinded panel of wild-type and squalene epoxidase (SQLE) target gene mutant T. rubrum and T. interdigitale strains were distributed to 10 European laboratories. Susceptibility to terbinafine, itraconazole, voriconazole and amorolfine) were performed according to the E.Def 9.3.1 method with and without addition of chloramphenicol and cycloheximide (final concentrations 50 mg/L and 300 mg/L, respectively). Plates were incubated at 25 °C (one laboratory used 30 °C) for 5-7 days until sufficient growth. MICs were determined visually (ignoring trailing growth for itraconazole) and spectrophotometrically with 90% and 50% endpoints yielding a total of 7,829 MICs. A. flavus ATCC 204304 and A. flavus CNM-CM1813 were included as controls. Results: 100%/96% (voriconazole) and 84%/84% (itraconazole) MIC determinations fell within the QC ranges for the two QC strains, respectively, and 96%/92% terbinafine MICs fell in a 0.25-1 mg/L 3 two-fold-dilution range suggesting a high interlaboratory reproducibility. Across the six methods, the number of terbinafine MEs varied from 2 (2.6%) to 5 (6.6%) for T. rubrum and between 0 and 2 (2.0%) for T. interdigitale (lowest for the CC-method (2.6%-4.4%/ 0-1% for T. rubrum/T. interdigitale). The difference between the modes for the wt and mutant population were ≥7 two-fold-dilutions in all cases (Table). If excluding a I121M/V237I T. rubrum mutant, and two mixed T. interdigitale strains, the number of VMEs were CC visual: T. rubrum: 1/77 (1.3%), CC spec-90%: 3/68 (4.4%) and CC spec-50%: 1/76 (1.3%), and none for T. interdigitale. The activity of voriconazole, itraconazole and amorolfine were quite uniform against T. rubrum and T. interdigitale, but unacceptably wide MIC ranges were found for the visual and spec-90% inhibition methods for itraconazole (data not shown). Conclusions: Although none of the laboratories perform dermatophyte testing at a regular basis an acceptable interlaboratory agreement and good separation between SQLE wt and mutants were found, suggesting a robust performance of the proposed method. [less ▲]

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See detailMolecular surveillance of anti-malarial drug resistance in Democratic Republic of Congo: high variability of chloroquinoresistance and lack of amodiaquinoresistance
Yobi, Doudou; Kayiba, Nadine; Mvumbi, Dieudonné et al

in Malaria Journal (2020), 19(121),

Background: The loss of chloroquine (CQ) efectiveness has led to its withdrawal from national policies as a frst-line treatment for uncomplicated malaria in several endemic countries, such as the ... [more ▼]

Background: The loss of chloroquine (CQ) efectiveness has led to its withdrawal from national policies as a frst-line treatment for uncomplicated malaria in several endemic countries, such as the Democratic Republic of Congo (DRC). The K76T mutation on the pfcrt gene has been identifed as a marker of CQ resistance and the SVMNT haplotype in codons 72–76 on the same gene has been associated with resistance to amodiaquine (AQ). In the DRC, the prevalence of K76T has decreased from 100% in 2000 to 63.9% in 2014. The purpose of this study was to determine the prevalence of K76T mutations in circulating strains of Plasmodium falciparum, 16 years after CQ withdrawal in the DRC and to investigate the presence of the SVMNT haplotype. Methods: In 2017, ten geographical sites across the DRC were selected. Dried blood samples were collected from patients attending health centres. Malaria was frst detected by a rapid diagnostic test (RDT) available on site (SD Bioline Malaria Ag Pf or CareStart Malaria Pf) or thick blood smear and then confrmed by a P. falciparum species-specifc real-time PCR assay. A pfcrt gene segment containing a fragment that encodes amino acids at positions 72–76 was amplifed by conventional PCR before sequencing. Results: A total of 1070 patients were enrolled. Of the 806 PCR-confrmed P. falciparum positive samples, 764 were successfully sequenced. The K76T mutation was detected in 218 samples (28.5%; 95% CI 25.4%–31.9%), mainly (96%) with the CVIET haplotype. Prevalence of CQ resistance marker was unequally distributed across the country, ranging from 1.5% in Fungurume to 89.5% in Katana. The SVMNT haplotype, related to AQ resistance, was not detected. Conclusion: Overall, the frequency of the P. falciparum CQ resistance marker has decreased signifcantly and no resistance marker to AQ was detected in the DRC in 2017. However, the between regions variability of CQ resistance remains high in the country. Further studies are needed for continuous monitoring of the CQ resistance level for its prospective re-use in malaria management. The absence of the AQ resistance marker is in line with the use of this drug in the current DRC malaria treatment policy. [less ▲]

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See detailMalaria risk assessment and mapping using satellite imagery and boosted regression trees in the Peruvian Amazon
Solano Villarreal, Elisa Yoan ULiege; Valdivia, Walter; Pearcy, Morgan et al

in Scientific Reports (2019)

This is the first study to assess the risk of co-endemic Plasmodium vivax and Plasmodium falciparum transmission in the Peruvian Amazon using boosted regression tree (BRT) models based on social and ... [more ▼]

This is the first study to assess the risk of co-endemic Plasmodium vivax and Plasmodium falciparum transmission in the Peruvian Amazon using boosted regression tree (BRT) models based on social and environmental predictors derived from satellite imagery and data. Yearly cross-validated BRT models were created to discriminate high-risk (annual parasite index API > 10 cases/1000 people) and veryhigh-risk for malaria (API > 50 cases/1000 people) in 2766 georeferenced villages of Loreto department, between 2010–2017 as other parts in the article (graphs, tables, and texts). Predictors were cumulative annual rainfall, forest coverage, annual forest loss, annual mean land surface temperature, normalized difference vegetation index (NDVI), normalized difference water index (NDWI), shortest distance to rivers, time to populated villages, and population density. BRT models built with predictor data of a given year efficiently discriminated the malaria risk for that year in villages (area under the ROC curve (AUC) > 0.80), and most models also effectively predicted malaria risk in the following year. Cumulative rainfall, population density and time to populated villages were consistently the top three predictors for both P. vivax and P. falciparum incidence. Maps created using the BRT models characterize the spatial distribution of the malaria incidence in Loreto and should contribute to malaria-related decision making in the area. [less ▲]

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See detailGroup B streptococcus neonatal invasive infections in Belgium 2010-2017, and characterization of isolated strains.
Melin, Pierrette ULiege; SACHELI, Rosalie ULiege; Lambotte, Olivia et al

in INMIS, International Committee (Ed.) INMIS 2019 Abstract book (2019, September)

Introduction/Background & Aims: Where intrapartum antibiotic-prophylaxis (IAP) is given to pregnant women colonized with Group B Streptococcus (GBS), the incidence of neonatal early-onset disease (EOD ... [more ▼]

Introduction/Background & Aims: Where intrapartum antibiotic-prophylaxis (IAP) is given to pregnant women colonized with Group B Streptococcus (GBS), the incidence of neonatal early-onset disease (EOD) has been successfully reduced; nevertheless, GBS is still the leading cause of severe disease among newborns, notably because the incidence of GBS late-onset disease (LOD) is not affected by IAP. Another strategy such as maternal immunization for prevention of both EOD/LOD is highly desirable worldwide. Aiming to describe GBS epidemiology and characterization of relevant epidemiological markers for vaccine development, surveillance of isolates causing neonatal disease is needed. We provide here results from the Belgian surveillance organized by the National Reference Centre(NRC). Methods: A total of 292 strains of GBS isolated from blood culture/cerebro-spinal fluid of newborns with invasive disease (149 EOD; 143 LOD) were sent to NRC by laboratories of a surveillance network, through years 2010-2017. Capsular-polysaccharide (CPS)-typing and pili-typing were performed with multiplex PCR assays. Multilocus sequence-typing and assignment to the hypervirulent clonal-complex (CC)17 was determined. Results: CPS type III isolates were responsible for 38.9% (n=58) of EOD cases, followed mainly by types Ia, V and II (22.1%, 18.1%, 8.1%). LOD cases were mainly caused by type III isolates (n=107, 74.8%), followed by types Ia (12.6%), V, Ib, IV and II (4.2%, 3.5%,2.8%, 2.1%). These distributions did not vary during the study period. A pili type was assigned to all isolates: at least one pili gene, PI2a, PI2b, or a combination of genes PI1-PI2a and PI1-PI2b. In 2016-2017, the hypervirulent-clone CC17 accounted for 33.3% of EOD (70.4% of type III) and 67% of LOD (89% of type III). Conclusions: The Belgian CPS distributions of isolates from EOD/LOD were similar to European data. One or 2 of 3 pilus-genes were detected in all isolates. CPS type III was predominant in both EOD/LOD and was mainly represented by CC-17 strains. [less ▲]

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See detailCharacterization of the treatment trajectory and assessment of the disease weight during uncomplicated malaria in the Democratic Republic of Congo
KAYIBA, Nadine; YOBI, Doudou; Devleesschauwer, Bart et al

Conference (2019, September)

Introduction: The emergence of Plasmodium falciparum (Pf) resistance to artemisinin (PfART-R) in Africa is a worrisome situation that would annihilate the progress made in reducing the global burden of ... [more ▼]

Introduction: The emergence of Plasmodium falciparum (Pf) resistance to artemisinin (PfART-R) in Africa is a worrisome situation that would annihilate the progress made in reducing the global burden of malaria. The discovery of mutations occurring in portions of the Pf gene sequence encoding kelch 13 (PfK13) – propeller domain and inducing PfART-R, has provided unprecedented opportunities for monitoring such resistance at large scale. Aim: This study aimed to review the PfK13 allelic polymorphism and its spatial distribution in Africa for drawing a baseline for subsequent epidemiological surveillance and containment efforts of PfART-R. Methods: A systematic review was performed according to PRISMA guidelines through six electronic databases consulted up to December 2018. Studies assessing the PfK13 gene in any of the 54 African countries were explored and data related to individual single nucleotide polymorphisms from each report and sampling location were geo-referenced and locus-referenced to be uploaded on maps displaying spatial and molecular patterns. Results: From 8,678 screened records, 50 reports were identified as eligible providing 22,739 Pf isolates successfully sequenced for the PfK13 and originating from 109 sites surveyed in 41 African countries. Overall 619 nonsynonymous (NS) mutants (2.7% of sequenced isolates) were reported at varied relative frequencies (0.5 to 50%) most often being K189T and A578S.Intermediate proportions (30 to 50%) of NS mutants were found in Western and Eastern Africa, moderate proportions (10 to 20%) in Middle Africa and low to very low proportions (<5%), elsewhere. NS mutations were not detected in 11 of 41 sampling countries. A total of 8 PfK13 NS mutations (F446I, C469Y, R515K, S522C, P553L, V568G, P574L, and A675V) out of 24 known as “associated molecular markers” for PfART-R were noticed at relative frequencies from 0.08 to 10.2%. One NS mutation (M476I) out of 6 established as “validated molecular markers” for PfART-R was reported at a relative frequency of 0.42%. Possible foci of NS mutations were noticed in Eastern, Western, and Middle Africa. Conclusion: Africa has noticed rare but alarming signals of possible emergence of Pf-ART-R. Proactive surveillance strategies are needed to be established in different African regions to refrain from massive development of resistance. [less ▲]

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See detailEvaluation of the Abbott RealTime quantitative CMV and EBV assays using the maxCycle protocol in a laboratory automation context
Bontems, Sébastien ULiege; BOREUX, Raphaël ULiege; CAPRARO, Valérie ULiege et al

in Journal of Virological Methods (2019), 270

Real-time PCR are often used for the diagnosis and monitoring of Cytomegalovirus (CMV)and Epstein-Barr virus (EBV)infections in susceptible populations. In this context, we evaluated the analytical ... [more ▼]

Real-time PCR are often used for the diagnosis and monitoring of Cytomegalovirus (CMV)and Epstein-Barr virus (EBV)infections in susceptible populations. In this context, we evaluated the analytical performances of the Abbott RealTime CMV/EBV maxCycle protocol automated on the m2000 platform (Abbott). It was compared to our routinely-used procedure consisting of a NucleoMag® DNA extraction automated on a STARlet platform followed by manually processed CMV and EBV quantitative real-time PCR (Diagenode). In this study, we showed that both EBV assays exhibited a similar sensitivity but with a better precision for the EBV Abbott RealTime assay. For the CMV performances, the Abbott assay was more sensitive and more precise than our routine method. The use of WHO International Standards also indicated a slight underestimation of the viral loads (−0.25 log10 IU/mL and −0.21 log10 IU/mL for CMV and EBV assays respectively)while these were rather overestimated with the Starlet/Diagenode method (0.48 log10 IU/mL and 0.19 log10 IU/mL for CMV and EBV assays respectively). These trends were confirmed using relevant whole-blood clinical samples and external quality controls. The workflows were also compared and we highlighted a significant technician hands-on time reduction (−63%)using the Abbott CMV/EBV maxCycle automated protocol. © 2019 Elsevier B.V. [less ▲]

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See detailMYCOSES : Surveillance épidémiologique en Belgique 2016-2017
Van beckhoven Dominique; SACHELI, Rosalie ULiege; Patteet Sofie et al

Report (2019)

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See detailSelf-testing in infectiology: is it the future?
Hayette, Marie-Pierre ULiege

Conference (2018, December 19)

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See detailFungiplex Candida et Aspergillus
Hayette, Marie-Pierre ULiege

Conference (2018, December 17)

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See detailDépistage intrapartum du Streptococcus agalactiae par PCR GenePOC GBS DS
MEEX, Cécile ULiege; Defêche, Justine ULiege; DEVEY, Anaïs ULiege et al

Poster (2018, December)

Les infections néonatales précoces causées par Streptococcus agalactiae (streptocoque du groupe B, GBS) peuvent être prévenues par administration d’une antibioprophylaxie intrapartum (AIP) aux femmes ... [more ▼]

Les infections néonatales précoces causées par Streptococcus agalactiae (streptocoque du groupe B, GBS) peuvent être prévenues par administration d’une antibioprophylaxie intrapartum (AIP) aux femmes identifiées GBS positives. Un test de dépistage vaginal rapide réalisé en début de travail permettrait une meilleure sélection des candidates à l’AIP que la stratégie basée sur un dépistage anténatal. OBJECTIFS Evaluation en laboratoire du test PCR GenePOCTM GBS DS (PCR GBS DS) sur frottis vaginal prélevé en intrapartum : performances et praticabilité du test en vue de sa réalisation en Point-Of-Care (POC). MATERIEL & METHODES De janvier à août 2018, inclusion de 102 frottis vaginaux prélevés en intrapartum avec le consentement de patientes admises en travail à la maternité du CHU de Liège. Collecte et évaluation se poursuivent. A la réception au laboratoire, décharge des frottis dans le milieu de conservation du kit PCR GBS DS: 150 µl utilisés pour réaliser le test PCR GBS DS sur système RevogeneTM, 10 µl mis en culture sur milieu sélectif Granada (Becton Dickinson, BD) et 300 µl inoculés en bouillon de Lim (BD). Après une nuit d’incubation, sous-culture sur Granada et gélose sélective chromogène StrepBselect (Biorad). Contrôle des discordances entre test PCR GBS DS et culture par PCR GenePOCTM GBS LB et PCR XpertTM GBS LB (Cepheid) sur les bouillons de Lim. RESULTATS Des cultures intrapartum, 12% étaient positives : 9 en primoculture et 3 après enrichissement. Le test PCR GBS DS a identifié 11 de ces échantillons positifs. Par comparaison avec la culture intrapartum, les sensibilité et spécificité du test PCR GBS DS, calculées sur base de ces premiers résultats, sont de 92 et 99% respectivement. Le taux d’erreur du test PCR GBS DS est de 2%. La réalisation du test PCR GBS DS et l’utilisation du système RevogeneTM sont extrêmement simples. Les résultats positifs ou négatifs sont obtenus en 75 minutes. DISCUSSION Les sensibilité et spécificité démontrées par le test PCR GBS DS réalisé au laboratoire sur frottis vaginaux intrapartum répondent aux exigences requises pour un dépistage intrapartum. Le délai de 75 minutes pour l’obtention des résultats dépasse les attentes idéales pour un test intrapartum. Ces performances devront être confirmées lorsque l’analyse sera réalisée en POC par des sages-femmes au bloc d’accouchement. [less ▲]

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See detailHepatic alveolar echinococcosis.
DETRY, Olivier ULiege; MEURISSE, Nicolas ULiege; Delwaide, Jean ULiege et al

in Acta Chirurgica Belgica (2018), 118(3), 200-201

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See detailEffectiveness of a Malaria Surveillance Strategy based on active case detection during high transmission season in the Peruvian Amazon
Moreno-Gutierrez, Diamantina; Llanos-Cuentas, Alejandro; Barboza, José Luis et al

in International Journal of Environmental Research and Public Health (2018), 15

Background: Faced with the resurgence of malaria, malaria surveillance in the Peruvian Amazon incorporated consecutive active case detection (ACD) interventions using light microscopy (LM) as reactive ... [more ▼]

Background: Faced with the resurgence of malaria, malaria surveillance in the Peruvian Amazon incorporated consecutive active case detection (ACD) interventions using light microscopy (LM) as reactive measure in communities with an unusual high number of cases during high transmission season (HTS). We assessed the effectiveness in malaria detection of this local ACD-based strategy. Methods: A cohort study was conducted in June–July 2015 in Mazan, Loreto. Four consecutive ACD interventions at intervals of 10 days were conducted in four riverine communities (Gamitanacocha, Primero de Enero, Libertad and Urco Miraño). In each intervention, all inhabitants were visited at home, and finger-prick blood samples collected for immediate diagnosis by LM and on filter paper for later analysis by quantitative real-time polymerase chain reaction (qPCR). Effectiveness was calculated by dividing the number of malaria infections detected using LM by the number of malaria infections detected by delayed qPCR. Results: Most community inhabitants (88.1%, 822/933) were present in at least one of the four ACD interventions. A total of 451 infections were detected by qPCR in 446 participants (54.3% of total participants); five individuals had two infections. Plasmodium vivax was the predominant species (79.8%), followed by P. falciparum (15.3%) and P. vivax-P. falciparum co-infections (4.9%). Most qPCR-positive infections were asymptomatic (255/448, 56.9%). The ACD-strategy using LM had an effectiveness of 22.8% (detection of 103 of the total qPCR-positive infections). Children aged 5–14 years, and farming as main economic activity were associated with P. vivax infections. Conclusions: Although the ACD-strategy using LM increased the opportunity of detecting and treating malaria infections during HTS, the number of detected infections was considerably lower than the real burden of infections (those detected by qPCR). [less ▲]

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See detailExemple pratique: dossier de validation de test de microbiologie
Hayette, Marie-Pierre ULiege

Conference (2018, November 24)

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See detailSelf-testing kits for infectious diseases: the point of view of a microbiologist
Hayette, Marie-Pierre ULiege

Conference (2018, November 16)

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See detailMalaria risk assessment at local level using satellite imagery and BRT in the Peruvian Amazon
Solano-Villarreal, Elisa; Valdivia, Walter; Linard, Catherine ULiege et al

in Archives of Public Health (2018, November 13), 77 (suppl 1)(7),

Background: Malaria in Loreto department remains a public health problem, accounting for more than 90% of reported cases in Peru. This is the first study in the Peruvian Amazon aimed at assessing the risk ... [more ▼]

Background: Malaria in Loreto department remains a public health problem, accounting for more than 90% of reported cases in Peru. This is the first study in the Peruvian Amazon aimed at assessing the risk of malaria transmission using satellite imagery and Boosted Regression Trees (BRT). Methods: Villages with at least one malaria case between 2010 and 2015 from the routine surveillance data in Loreto were georeferenced and their cases aggregated by year and species. Social and environmental variables were derived from Landsat satellite imagery and other spatial data, then included as explanatory variables into a crossvalidated Poisson BRT model for malaria incidence at the local level. Time-dependent explanatory variables included forest coverage (FC, %), annual forest loss (FL,%), cumulative annual rainfall (CAR, mm), annual-mean land surface temperature (LST, oC), normalised difference vegetation index (NDVI), and normalised difference water index (NDWI). Other variables were Euclidean shortest distance to rivers (SDR, meters), time to major populated villages/towns (TPV, minutes), and night-time lights (NTL, mean value 2010-2013) as proxy of population density. BRT accounts for nonlinearities and interactions between factors with high predictive accuracy for disease risk mapping. Results: A total of 1524 villages were included in the analysis (70% of total Loreto’s villages). More than 90% of relative influence in the overall malaria incidence was explained by five variables: NTL (67.8%), TPV (8.1%), FC (6.5%), CAR (5%) and SDR (4.6%). The analysis by species showed a higher influence of environmental variables (CAR, LST, NDVI and NDWI) for P. falciparum (18.4%) than for P. vivax incidence (9.7%). Malaria risk maps were generated based on model predictions taking into account the relative influence of variables. Conclusions: Remotely sensed data analysed using BRT allowed for maps delimiting areas of high malaria risk in Loreto. These maps will help malaria stakeholders to prioritise areas for control interventions. [less ▲]

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