Publications by authors named "Grigg M"

The Apicomplexa are a phylum of single-celled eukaryotes that can infect humans and include the mosquito-borne parasite , the cause of malaria. Viruses that infect non- spp. disease-causing protozoa affect the pathogen life cycle and disease outcomes.

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Zoonotic malaria presents a major public health challenge in Southeast Asia. Plasmodium cynomolgi coinfects the same macaque hosts and mosquito vectors as the most common cause of zoonotic malaria, Plasmodium knowlesi. Plasmodium cynomolgi appears morphologically similar to Plasmodium vivax on microscopy and can amplify P.

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Reduced deformability of both infected and uninfected red blood cells (RBC) contributes to pathogenesis in falciparum malaria. Whole blood RBC-deformability is not well-characterised in vivax malaria. We used a laser-assisted optical rotational cell analyzer to measure the RBC deformability in fresh whole blood from Malaysian patients with vivax malaria (n=25).

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Apicomplexa are single-celled eukaryotes that can infect humans and include the mosquito-borne parasite , the cause of malaria. Increasing rates of drug resistance in human-only species are reducing the efficacy of control efforts and antimalarial treatments. There are also rising cases of , the only zoonotic species that causes severe disease and death in humans.

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Article Synopsis
  • This study investigates the effectiveness and safety of different primaquine dosing strategies in preventing relapsing Plasmodium vivax malaria in children under 15 years.
  • A systematic review was conducted, analyzing various studies involving children treated with primaquine, focusing on those who received treatment over multiple days and were followed up for at least 28 days.
  • The findings from 3514 children across 27 studies were compiled to analyze different dosing regimens, assess the risk of recurrent malaria, and evaluate tolerability and safety concerning adverse effects.
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  • Cutaneous leishmaniasis in Sri Lanka is unusual, as it is typically caused by Leishmania donovani, which is mainly associated with visceral disease.
  • Genome analysis of clinical isolates from Sri Lanka revealed that both L. donovani and L. tropica are present, with some L. tropica strains linked to older Indian isolates rather than recent hybrids.
  • The findings suggest that L. donovani is not the sole cause of cutaneous leishmaniasis in Sri Lanka, pointing to potential interspecies hybrids contributing to the disease.
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The risk of severe malaria from the zoonotic parasite Plasmodium knowlesi approximates that from P. falciparum. In severe falciparum malaria, neutrophil activation contributes to inflammatory pathogenesis, including acute lung injury (ALI).

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Osteoprotegerin (OPG) is a soluble decoy receptor for receptor activator of NF-ƙB ligand (RANKL) and TNF-related apoptosis-inducing ligand (TRAIL), and is increasingly recognised as a marker of poor prognosis in a number of diseases. Here we demonstrate that in Malaysian adults with falciparum and vivax malaria, OPG is increased, and its ligands TRAIL and RANKL decreased, in proportion to disease severity. In volunteers experimentally infected with and , RANKL was suppressed, while TRAIL was unexpectedly increased, suggesting binding of OPG to RANKL prior to TRAIL.

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The evolutionary pressures exerted by viral infections have led to the development of various cellular proteins with potent antiviral activities, some of which are known as antiviral restriction factors. TRIpartite Motif-containing protein 5 alpha (TRIM5α) is a well-studied restriction factor of retroviruses that exhibits virus- and host-species-specific functions in protecting against cross-primate transmission of specific lentiviruses. This specificity is achieved at the level of the host gene through positive selection predominantly within its C-terminal B30.

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Unlabelled: The Endosomal Sorting Complex Required for Transport (ESCRT) is an evolutionarily conserved machinery that performs reverse-topology membrane scission in cells universally required from cytokinesis to budding of enveloped viruses. Upstream acting ESCRT-I and ALIX control these events and link recruitment of viral and cellular partners to late-acting ESCRT-III CHMP4 through incompletely understood mechanisms. Using structure-function analyses combined with super-resolution imaging, we show that ESCRT-I and ALIX function as distinct helical filaments .

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The ability to discriminate infection between closely related species within the species complex, specifically and is critical to inform the clinical diagnosis and determine the most efficacious treatment modality. We designed a nested primer set targeting the rRNA Internal Transcribed Spacer 2 (ITS2), located on Chromosome 27, to distinguish among all human infective species. Separate nested and single primer pairs were developed for conventional and quantitative PCR approaches respectively.

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Diarrheal diseases are the second leading cause of death in children worldwide. Epidemiological studies show that co-infection with decreases the severity of diarrhea. Here, we show that is highly prevalent in the stools of asymptomatic school-aged children.

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The apicomplexan intracellular parasite Toxoplasma gondii is a major food borne pathogen that is highly prevalent in the global population. The majority of the T. gondii proteome remains uncharacterized and the organization of proteins into complexes is unclear.

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Background: The interaction between iron status and malaria is incompletely understood. We evaluated longitudinal changes in iron homeostasis in volunteers enrolled in malaria volunteer infection studies (VIS) and in Malaysian patients with falciparum and vivax malaria.

Methods: We retrieved data and samples from 55 participants (19 female) enrolled in malaria VIS, and 171 patients (45 female) with malaria and 30 healthy controls (13 female) enrolled in clinical studies in Malaysia.

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spp. are protozoan parasites that cause severe illness in vulnerable human populations. Obtaining pure DNA from clinical and environmental samples is challenging because the oocysts shed in contaminated feces are limited in quantity, difficult to purify efficiently, may derive from multiple species, and yield limited DNA (<40 fg/oocyst).

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Article Synopsis
  • Toxoplasma gondii is a widespread protozoan pathogen with different clonal types seen across various continents, while South/Central America has more genetically diverse strains.
  • A study compared genome data from Japanese and Chinese T. gondii strains using a new software called POPSICLE and included non-viable strains that were revived for analysis.
  • Results revealed genetic mixing between different haplogroups, indicating complex ancestral relationships between Far East Asian and American T. gondii strains, which enhances our understanding of its spread and evolution.
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Background: The emergence of the zoonotic monkey parasite as the dominant cause of malaria in Malaysia has disrupted current national WHO elimination goals. Malaysia has free universal access to malaria care; however, out-of-pocket costs are unknown. This study estimated household costs of illness attributable to malaria due to against other non-zoonotic species infections in Sabah, Malaysia.

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is a leading cause of severe diarrhea and mortality in young children and infants in Africa and southern Asia. More than twenty species infect humans, of which and are the major agents causing moderate to severe diarrhea. Relatively few genetic markers are typically applied to genotype and/or diagnose .

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Background: Zoonotic and symptomatic and asymptomatic infections occur across endemic areas of Southeast Asia. Most infections are low-parasitemia, with an unknown proportion below routine microscopy detection thresholds. Molecular surveillance tools optimizing the limit of detection (LOD) would allow more accurate estimates of zoonotic malaria prevalence.

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Background: Natural interspecific hybridization between the human parasite (Schistosoma haematobium [Sh]) and bovine parasites (Schistosoma bovis [Sb], Schistosoma curassoni [Sc]) is increasingly reported in Africa. We developed a multi-locus PCR DNA-Seq strategy that amplifies two unlinked nuclear (transITS, BF) and two linked organellar genome markers (CO1, ND5) to genotype S. haematobium eggs collected from infected people in Ile Oluji/Oke Igbo, Ondo State (an agrarian community) and Kachi, Jigawa State (a pastoral community) in Southwestern and Northern Nigeria, respectively.

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spp. are protozoan parasites that cause severe illness in vulnerable human populations. Obtaining pure DNA from clinical and environmental samples is challenging because the oocysts shed in contaminated feces are limited in quantity, difficult to purify efficiently, may derive from multiple species, and yield limited DNA (<40 fg/oocyst).

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Plasmodium vivax lactate dehydrogenase (PvLDH) is an essential enzyme in the glycolytic pathway of P. vivax. It is widely used as a diagnostic biomarker and a measure of total-body parasite biomass in vivax malaria.

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Commensal protists and gut bacterial communities exhibit complex relationships, mediated at least in part through host immunity. To improve our understanding of this tripartite interplay, we investigated community and functional dynamics between the murine protist Tritrichomonas musculus and intestinal bacteria in healthy and B-cell-deficient mice. We identified dramatic, protist-driven remodeling of resident microbiome growth and activities, in parallel with Tritrichomonas musculus functional changes, which were accelerated in the absence of B cells.

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Background: Plasmodium knowlesi is a zoonotic parasite that causes malaria in humans. The pathogen has a natural host reservoir in certain macaque species and is transmitted to humans via mosquitoes of the Anopheles Leucosphyrus Group. The risk of human P.

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Disease surveillance aims to collect data at different times or locations, to assist public health authorities to respond appropriately. Surveillance of the simian malaria parasite, , is sparse in some endemic areas and the spatial extent of transmission is uncertain. Zoonotic transmission of has been demonstrated throughout Southeast Asia and represents a major hurdle to regional malaria elimination efforts.

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