A5017390968- Malaria Research and Control
- Mosquito-borne diseases and control
- Trypanosoma species research and implications
- Vector-borne infectious diseases
- Computational Drug Discovery Methods
- Research on Leishmaniasis Studies
- Bird parasitology and diseases
- Hepatitis B Virus Studies
- Advanced biosensing and bioanalysis techniques
- Cardiovascular Issues in Pregnancy
- vaccines and immunoinformatics approaches
- Travel-related health issues
- Multiple Myeloma Research and Treatments
- Molecular Biology Techniques and Applications
- Digital Imaging for Blood Diseases
- Heme Oxygenase-1 and Carbon Monoxide
- Legionella and Acanthamoeba research
- Advanced Biosensing Techniques and Applications
- Biosensors and Analytical Detection
- Herpesvirus Infections and Treatments
- Insect symbiosis and bacterial influences
- Invertebrate Immune Response Mechanisms
- Ocular Infections and Treatments
- Primate Behavior and Ecology
- Bacterial biofilms and quorum sensing
London School of Hygiene & Tropical Medicine
2013-2024
University of London
2005-2024
Universidade Federal Fluminense
2024
Shoklo Malaria Research Unit
2024
Public Health England
2013-2023
Concentration Heat and Momentum (United Kingdom)
2022
Rotunda Hospital
2021
Hospital for Tropical Diseases
2011
Universidad Peruana Cayetano Heredia
2007
Birkbeck, University of London
2004-2005
Background A century after its discovery, Chagas disease still represents a major neglected tropical threat. Accurate diagnostics tools as well surrogate markers of parasitological response to treatment are research priorities in the field. The purpose this study was evaluate performance PCR methods detection Trypanosoma cruzi DNA by an external quality evaluation. Methodology/Findings An international collaborative launched expert laboratories from 16 countries. Currently used strategies...
Background. Malaria in humans is caused by apicomplexan parasites belonging to 5 species of the genus Plasmodium. Infections with Plasmodium ovale are widely distributed but rarely investigated, and resulting burden disease not known. Dimorphism defined genes has led P. being divided into classic variant types. We hypothesized that these dimorphs represent distinct parasite species.
Abstract Five human cases of infection with the simian malaria parasite Plasmodium knowlesi from Palawan, Philippines, were confirmed by nested PCR. This study suggests that this zoonotic is found across a relatively wide area in Palawan and documents autochthonous country.
The majority of the keratitis-causing Acanthamoeba isolates are genotype T4. In an attempt to determine whether predominance T4 in keratitis is due greater virulence or prevalence this genotype, genotypes were determined for 13 and 12 environmental from Iran. Among clinical isolates, eight (61.5 %) belonged T4, two (15.3 T3 three (23 T2 genotype. contrast, tested present study (7/12, 58.3 %), followed by 4/12 (33.3 %). addition, six new UK cases determined. Of these, five (83.3 one was (16.6...
It has been proposed that ovale malaria in humans is caused by two closely related but distinct species of parasite, Plasmodium curtisi and wallikeri. was recently shown these parasite types are sympatric at the country level. However, it remains possible localised geographic, temporal or ecological barriers exist within endemic countries which prevent recombination between genomes species. Here, using conventional real-time quantitative PCR (qPCR) methods specifically designed to...
Abstract We demonstrate, for the first time, multiplexed determination of microbial species from whole blood using paper‐folding technique origami to enable sequential steps DNA extraction, loop‐mediated isothermal amplification (LAMP), and array‐based fluorescence detection. A low‐cost handheld flashlight reveals presence final amplicon naked eye, providing a “sample‐to‐answer” diagnosis finger‐prick volume human blood, within 45 min, with minimal user intervention. To demonstrate method,...
ABSTRACT We present case histories of four patients treated with artemether-lumefantrine for falciparum malaria in UK hospitals 2015 to 2016. Each subsequently presented recurrent symptoms and Plasmodium parasitemia within 6 weeks treatment no intervening travel countries where is endemic. Parasite isolates, all African origin, harbored variants at some candidate resistance loci. No evidence pfk13 -mediated artemisinin was found. Vigilance signs unsatisfactory antimalarial efficacy among...
Brazil is a unique and understudied setting for malaria, with complex foci of transmission associated human environmental conditions. An understanding the population genomic diversity
The principal agent of mucocutaneous leishmaniasis (MCL) is the South American protozoan parasite Leishmania (Viannia) braziliensis. This organism generally considered to be clonal, that is, it does not undergo genetic exchange. Nevertheless, apparent hybrids between several species have been reported in New World and Old World. When we characterized isolates from a single focus cutaneous (CL) MCL, found remarkable phenotypic genotypic diversity, with 12 zymodemes 20 microsatellite...
Ovale malaria is caused by two closely related species of protozoan parasite: Plasmodium ovale curtisi and wallikeri Although clearly distinct genetically, there have been no studies comparing the morphology, life cycle or epidemiology these parasites. We tested hypothesis that differ in duration latency prior to presentation with symptoms blood-stage infection.PCR was used identify P infections among archived blood from UK patients. Latency periods, estimated as time between entry into...
Whole-genome sequencing (WGS) of microbial pathogens from clinical samples is a highly sensitive tool used to gain deeper understanding the biology, epidemiology, and drug resistance mechanisms many infections. However, WGS organisms which exhibit low densities in their hosts challenging due high levels host genomic DNA (gDNA), leads very coverage genome. Plasmodium vivax, most widely distributed form malaria, especially difficult because parasite lack an ex vivo culture system. Current...
BackgroundMany health facilities in malaria endemic countries are dependent on Rapid diagnostic tests (RDTs) for diagnosis and some National Health Service (NHS) hospitals without expert microscopists rely them out of hours. The emergence P. falciparum lacking the gene encoding histidine-rich protein 2 3 (HRP2 HRP3) escaping RDT detection threatens progress control elimination. Currently, confirmation negative due to deletion pfhrp2 pfhrp3, which encodes a cross-reactive isoform, requires...
Despite the high burden of Plasmodium vivax malaria in South Asian countries, genetic diversity circulating parasite populations is not well described. Determinants antimalarial drug susceptibility for P. region have been characterised. Our genomic analysis global (n = 558) establishes isolates 92) as a distinct subpopulation, which shares ancestry with some East African and parasites. Signals positive selection are linked to resistance-associated loci including pvkelch10, pvmrp1, pvdhfr...
Abstract Background Recent cases of clinical failure in malaria patients the United Kingdom (UK) treated with artemether-lumefantrine have implications for chemotherapy worldwide. Methods Parasites were isolated from an index case confirmed Plasmodium falciparum treatment after standard treatment, and comparable travel-acquired UK cases. Drug susceptibility vitro genotypes at 6 resistance-associated loci determined all parasite isolates compared outcomes each donor. Results A traveler, who...
Abstract Despite Plasmodium ovale curtisi ( Poc ) and wallikeri Pow being important human-infecting malaria parasites that are widespread across Africa Asia, little is known about their genome diversity. Morphologically identical, indistinguishable commonly misidentified . Recent rises in the incidence of / infections have renewed efforts to address fundamental knowledge gaps biology, develop diagnostic tools understand epidemiological dynamics burden. A major roadblock has been...
Although Plasmodium vivax parasites are the predominant cause of malaria outside sub-Saharan Africa, they not always prioritised by elimination programmes. P. is resilient and poses challenges through its ability to re-emerge from dormancy in human liver. With observed growing drug-resistance increasing reports life-threatening infections, new tools inform efforts needed. In order halt transmission, we need better understand dynamics movement parasites, reservoirs infection design targeted...
The first isolation in the UK of Balamuthia mandrillaris amoebae from a fatal case granulomatous amoebic meningoencephalitis is reported. Using primary cultures human brain microvascular endothelial cells (HBMECs), were isolated and cerebrospinal fluid (CSF). showed cytopathic effect at 20–28 days, but morphologically identifiable B. seen cleared plaques subcultures 45 days. identification organism was later confirmed using PCR on Chelex-treated extracts. Serum taken while patient still...
Abstract We demonstrate, for the first time, multiplexed determination of microbial species from whole blood using paper‐folding technique origami to enable sequential steps DNA extraction, loop‐mediated isothermal amplification (LAMP), and array‐based fluorescence detection. A low‐cost handheld flashlight reveals presence final amplicon naked eye, providing a “sample‐to‐answer” diagnosis finger‐prick volume human blood, within 45 min, with minimal user intervention. To demonstrate method,...
Abstract The genomic diversity of Plasmodium malariae malaria parasites is understudied, partly because infected individuals tend to present with low parasite densities, leading difficulties in obtaining sufficient DNA for genome analysis. Selective whole amplification (SWGA) increases the relative levels pathogen a clinical sample, but has not been adapted P. parasites. Here we design customized SWGA primers which successfully amplify extracted directly from unprocessed blood samples...
ObjectivesOur objective was to systematically investigate false-negative histidine-rich protein 2 rapid diagnostic tests (HRP2-RDT) in imported Plasmodium falciparum malaria cases from travelers the UK and Republic of Ireland (RoI).MethodsFive travellers returning RoI East Africa were reported PHE Malaria Reference Laboratory as negative according (HRP2)-RDT. The investigated using microscopic, RDT, molecular, genomic, vitro approaches.ResultsIn each case, HRP2-RDT negative, whereas...
Plasmodium malariae parasites are widely observed across the tropics and sub-tropics. This slow-growing species, known to maintain chronic asymptomatic infections, has been associated with reduced antimalarial susceptibility. We analyse 251 P. genomes from 28 countries, leveraging 131,601 high-quality SNPs, demonstrate segregation of African Asian isolates. Signals recent evolutionary selection were identified in genes encoding putative surface proteins (pmmsp1) erythrocyte invasion...
Plasmodium malariae is widely distributed across the tropics, causing symptomatic malaria in humans with a 72-hour fever periodicity, and may present after latency periods lasting up to many decades. Delayed occurrence of symptoms observed using chemoprophylaxis, or patients having received therapies targeting P. falciparum intraerythrocytic asexual stages, but few investigators have addressed biological basis ability persist human host. To investigate these interesting features...