A5089605697- Malaria Research and Control
- Mosquito-borne diseases and control
- Vector-borne infectious diseases
- Bird parasitology and diseases
- Vibrio bacteria research studies
- Viral Infections and Vectors
- Hepatitis B Virus Studies
- Parasite Biology and Host Interactions
- Travel-related health issues
- Aquaculture disease management and microbiota
- Complement system in diseases
- Hemoglobinopathies and Related Disorders
- Parasites and Host Interactions
- Global Maternal and Child Health
- HIV Research and Treatment
- Evolution and Genetic Dynamics
- Drug Transport and Resistance Mechanisms
- Digital Imaging for Blood Diseases
- Neonatal Health and Biochemistry
- Invertebrate Immune Response Mechanisms
- Molecular Biology Techniques and Applications
- Data Stream Mining Techniques
- Drug-Induced Hepatotoxicity and Protection
- Diverse Scientific Research Studies
- Antibiotic Resistance in Bacteria
University of Notre Dame
2018-2025
The Ohio State University
2024
Kwame Nkrumah University
2024
Kwame Nkrumah University of Science and Technology
2022-2024
University of Science and Technology
2022-2024
Walter and Eliza Hall Institute of Medical Research
2014-2023
The University of Melbourne
2014-2023
Korea University of Science and Technology
2022
Notre Dame College
2020
Notre Dame University
2020
Abstract Malaria infections occurring below the limit of detection standard diagnostics are common in all endemic settings. However, key questions remain surrounding their contribution to sustaining transmission and whether they need be detected targeted achieve malaria elimination. In this study we analyse a range datasets quantify density, detectability, course infection infectiousness subpatent infections. Asymptomatically infected individuals have lower parasite densities on average low...
The World Health Organization recommends parasitological confirmation of all suspected malaria cases by microscopy or rapid diagnostic tests (RDTs) before treatment. These conventional tools are widely used for point-of-care diagnosis in spite their poor sensitivity at low parasite density. Previous studies Ghana have compared and RDT using standard 18S rRNA PCR as reference with varying outcomes. However, how these compare ultrasensitive varATS qPCR has not been studied. This study,...
Introduction Solomon Islands is intensifying national efforts to achieve malaria elimination. A long history of indoor spraying with residual insecticides, combined recently distribution lasting insecticidal nets and artemether-lumefantrine therapy, has been implemented in Islands. The impact these interventions on local endemicity Plasmodium spp. unknown. Methods In 2012, a cross-sectional survey 3501 residents all ages was conducted Ngella, Central Province, Prevalence falciparum, P....
A better understanding of human-to-mosquito transmission is crucial to control malaria. In order assess factors associated with gametocyte carriage, 2083 samples were collected in a cross-sectional survey Papua New Guinea. Plasmodium species detected by light microscopy and qPCR gametocytes detection pfs25 pvs25 mRNA transcripts reverse-transcriptase PCR (qRT-PCR). The parasite prevalence was 18.5% for falciparum 13.0% P. vivax. 52.5% all infections submicroscopic. Gametocytes 60%...
Amplicon deep sequencing permits sensitive detection of minority clones and improves discriminatory power for genotyping multi-clone Plasmodium falciparum infections. New amplicon data analysis protocols are needed in epidemiological studies drug efficacy trials P. falciparum.Targeted molecular marker csp novel cpmp was conducted duplicate on mixtures parasite culture strains 37 field samples. A protocol allowing to multiplex up 384 samples a single run applied. Software "HaplotypR"...
Abstract Accurate quantification of parasite density in the human host is essential for understanding biology and pathology malaria. Semi-quantitative molecular methods are widely applied, but need an external standard curve makes it difficult to compare estimates across studies. Droplet digital PCR (ddPCR) allows direct without a curve. ddPCR was used diagnose quantify P. falciparum vivax clinical patients as well asymptomatic samples. yielded highly reproducible measurements range...
Plasmodium vivax is the geographically most widespread human malaria parasite. To analyze patterns of microsatellite diversity and population structure across countries different transmission intensity, genotyping data from 11 markers was either generated or compiled 841 isolates four continents collected in 1999–2008. Diversity highest South-East Asia (mean allelic richness 10.0–12.8), intermediate South Pacific (8.1–9.9) Madagascar Sudan (7.9–8.4), lowest America Central (5.5–7.2). A...
Most rapid diagnostic tests for Plasmodium falciparum malaria target the Histidine-Rich Proteins 2 and 3 (HRP2 HRP3). Deletions of hrp2 hrp3 genes result in false-negative are a threat control. A novel assay molecular surveillance / deletions was developed based on droplet digital PCR (ddPCR). The quantifies , control gene with very high accuracy. theoretical limit detection 0.33 parasites/µl. deletion reliably detected mixed infections wild-type -deleted parasites at density >100...
BackgroundMany antimalarial interventions are accompanied by molecular monitoring of parasite infections, and a number typing techniques based on different polymorphic marker genes used. Here, we describe genotyping technique that provides fast precise approach to study Plasmodium vivax infection dynamics during circumstances in which individual clones must be followed over time. The method was tested with samples from an vivo drug efficacy MethodsThe sizes polymerase chain reaction...
Plasmodium falciparum and vivax cause the majority of human malaria cases. Research efforts predominantly focus on P. because clinical severity infection associated mortality rates. However, affects more people in a wider global range. Furthermore, unlike falciparum, can persist liver as dormant hypnozoites that be activated weeks to years after primary infection, causing relapse symptomatic blood stages. This feature makes unique difficult eliminate with standard tools vector control...
Introduction The human malaria parasite, Plasmodium vivax, is proving more difficult to control and eliminate than falciparum in areas of co-transmission. Comparisons the genetic structure sympatric parasite populations may provide insight into mechanisms underlying resilience P. vivax can help guide programs. Methodology/Principle findings isolates representing four on north coast Papua New Guinea (PNG) were genotyped using microsatellite markers compared with previously published data from...
Plasmodium vivax is highly endemic in the lowlands of Papua New Guinea and accounts for a large proportion malaria cases children less than 5 years age. We collected 2117 blood samples at 2-monthly intervals from cohort 268 aged 1 to 4.5 estimated diversity multiplicity P. infection. All clones were genotyped using merozoite surface protein F3 fragment (msp1F3) microsatellite MS16 as molecular markers. High was observed with msp1F3 (HE = 88.1%) 97.8%). Of 1162 positive samples, 74% harbored...
Low-density asymptomatic infections of Plasmodium spp. are common in low endemicity areas worldwide, but outside Africa, their contribution to malaria transmission is poorly understood. Community-based studies with highly sensitive molecular diagnostics needed quantify the reservoir falciparum and P. vivax Thai communities.A cross-sectional survey 4309 participants was conducted three endemic Kanchanaburi Ratchaburi provinces Thailand 2012. The presence parasites determined using 18S rRNA...
Abstract Background Land use change has increasingly been expanding throughout the world in past decades. It can have profound effects on spatial and temporal distribution of vector borne diseases like malaria through ecological habitat change. Understanding disease occurrence impact prevention interventions under this intense environmental modification is important for effective efficient control strategy. Methods A descriptive study was conducted by reviewing health service records at...
Molecular and genomic surveillance is becoming increasingly used to track malaria control elimination efforts. Blood samples can be collected as whole blood stored at - 20 °C until DNA extraction, or dried spots (DBS), circumventing the need for a cold chain. Despite wide use of either method, systematic comparisons how method sample preservation affects limit detection (LOD) molecular diagnosis proportion recovered downstream applications are lacking.Extractions based on spin columns,...
Abstract Zanzibar has made significant progress toward malaria elimination, but recent stagnation requires novel approaches. We developed a highly multiplexed droplet digital PCR (ddPCR)-based amplicon sequencing method targeting 35 microhaplotypes and drug-resistance loci, successfully sequenced 290 samples from five districts covering both main islands. Here, we elucidate fine-scale Plasmodium falciparum population structure infer relatedness connectivity of infections using an...
Genomic epidemiology holds promise for malaria control and elimination efforts, example by informing on Plasmodium falciparum genetic diversity prevalence of mutations conferring anti-malarial drug resistance. Limited sequencing infrastructure in many malaria-endemic areas prevents the rapid generation genomic data. To address these issues, we developed validated assays P . nanopore endemic sites using a mobile laboratory, targeting key antimalarial resistance markers microhaplotypes. Using...
Introduction The importance of Plasmodium vivax in malaria elimination is increasingly being recognized, yet little known about its population size and genetic structure the South Pacific, an area that focus intensified control. Methods We have genotyped 13 microsatellite markers 295 P. isolates from four geographically distinct sites Papua New Guinea (PNG) one site Solomon Islands, representing different transmission intensities. Results Diversity was very high with expected heterozygosity...
Background When both parasite species are co-endemic, Plasmodium vivax incidence peaks in younger children compared to P. falciparum. To identify differences the number of blood stage infections these and its potential link acquisition immunity, we have estimated molecular force blood-stage infection (molFOB, i.e. genetically distinct over time), it previously reported values for Methods molFOB was by high resolution genotyping parasites samples collected 16 months a cohort 264 Papua New...
The human malaria parasite Plasmodium vivax is more resistant to control strategies than falciparum, and maintains high genetic diversity even when transmission low. To investigate whether declining P. leads increasing population structure that would facilitate elimination, we genotyped samples from across the Southwest Pacific region, which experiences an eastward decline in transmission, as well two time points at one site (Tetere, Solomon Islands) during intensified control. Analysis of...