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1.
Sci Rep ; 14(1): 16734, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39030306

ABSTRACT

The interactions of environmental, geographic, socio-demographic, and epidemiological factors in shaping mosquito-borne disease transmission dynamics are complex and changeable, influencing the abundance and distribution of vectors and the pathogens they transmit. In this study, 27 years of cross-sectional malaria survey data (1990-2017) were used to examine the effects of these factors on Plasmodium falciparum and Plasmodium vivax malaria presence at the community level in Africa and Asia. Monthly long-term, open-source data for each factor were compiled and analyzed using generalized linear models and classification and regression trees. Both temperature and precipitation exhibited unimodal relationships with malaria, with a positive effect up to a point after which a negative effect was observed as temperature and precipitation increased. Overall decline in malaria from 2000 to 2012 was well captured by the models, as was the resurgence after that. The models also indicated higher malaria in regions with lower economic and development indicators. Malaria is driven by a combination of environmental, geographic, socioeconomic, and epidemiological factors, and in this study, we demonstrated two approaches to capturing this complexity of drivers within models. Identifying these key drivers, and describing their associations with malaria, provides key information to inform planning and prevention strategies and interventions to reduce malaria burden.


Subject(s)
Malaria, Falciparum , Humans , Cross-Sectional Studies , Africa/epidemiology , Asia/epidemiology , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Malaria, Falciparum/transmission , Malaria, Vivax/epidemiology , Malaria, Vivax/parasitology , Malaria, Vivax/transmission , Socioeconomic Factors , Geography , Plasmodium falciparum , Malaria/epidemiology , Malaria/transmission , Temperature , Mosquito Vectors/parasitology , Animals , Plasmodium vivax , Environment
2.
Parasite Epidemiol Control ; 26: e00362, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38975253

ABSTRACT

Malaria is still a public health problem in tropical countries like India; major malaria parasite species are Plasmodium falciparum and P. vivax. Of which, P. vivax is responsible for ∼40% of the malaria burden at least in the Indian scenario. Unfortunately, there is limited data on the population structure and genetic diversity of P. vivax parasites in India. In this study, we investigated the genetic diversity of P. vivax strains in the South-west district, Delhi and, Nuh district, Haryana [National Capital Region (NCR)], using a polymorphic marker- P. vivax merozoite surface protein-3α (PvMSP-3α) gene. Dried blood spots from microscopically confirmed P. vivax patients were used for investigation of the PvMSP-3α gene. PCR-RFLP was performed on the PvMSP-3α gene to investigate the genotypes and allelic variability with HhaI and AluI restriction enzymes. In total, 40 successfully PCR amplified PvMSP-3α gene segments were subjected to RFLP analysis. Amplified products showed three different base pair size variations viz. genotype A in 31(77.5%), genotype B in 4(10%) and genotype C in 5(12.5%) P. vivax specimens. RFLP with HhaI and AluI revealed 17 (H1-H17) and 25 (A1-A25) allelic variants, respectively. Interestingly, two similar sub-allelic variants, ie. H8 (with HhaI), and A4 (with AluI) clustered within the rural area of Nuh district, Haryana in two samples. With this study, we propose to commission such type of genetic diversity analysis of P. vivax to investigate the circulating genotypes of the parasites from distinct geographical locations across India, that can have significant implications in understanding the population structures of P. vivax.

3.
Cell Rep Med ; 5(7): 101654, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39019011

ABSTRACT

Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is a leading blood-stage malaria vaccine antigen target, currently in a phase 2b clinical trial as a full-length soluble protein/adjuvant vaccine candidate called RH5.1/Matrix-M. We identify that disordered regions of the full-length RH5 molecule induce non-growth inhibitory antibodies in human vaccinees and that a re-engineered and stabilized immunogen (including just the alpha-helical core of RH5) induces a qualitatively superior growth inhibitory antibody response in rats vaccinated with this protein formulated in Matrix-M adjuvant. In parallel, bioconjugation of this immunogen, termed "RH5.2," to hepatitis B surface antigen virus-like particles (VLPs) using the "plug-and-display" SpyTag-SpyCatcher platform technology also enables superior quantitative antibody immunogenicity over soluble protein/adjuvant in vaccinated mice and rats. These studies identify a blood-stage malaria vaccine candidate that may improve upon the current leading soluble protein vaccine candidate RH5.1/Matrix-M. The RH5.2-VLP/Matrix-M vaccine candidate is now under evaluation in phase 1a/b clinical trials.


Subject(s)
Antibodies, Protozoan , Malaria Vaccines , Plasmodium falciparum , Protozoan Proteins , Vaccines, Virus-Like Particle , Animals , Malaria Vaccines/immunology , Antibodies, Protozoan/immunology , Plasmodium falciparum/immunology , Vaccines, Virus-Like Particle/immunology , Humans , Mice , Protozoan Proteins/immunology , Rats , Malaria, Falciparum/prevention & control , Malaria, Falciparum/immunology , Antigens, Protozoan/immunology , Female , Carrier Proteins/immunology , Mice, Inbred BALB C
4.
Antimicrob Agents Chemother ; : e0044024, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023263

ABSTRACT

Cyclin-dependent kinase 7 is an attractive therapeutic target for the treatment of cancers, and a previous report suggested that Plasmodium falciparum CDK7 is a potential drug target for developing new anti-malarial drugs. In this study, we aimed to characterize and evaluate the drug target potential of Theileria annulata CDK7. Theileria annulata is responsible for tropical theileriosis, which induces a phenotype similar to cancerous cells like immortalization, hyperproliferation, and dissemination. Virtual screening of the MyriaScreen II library predicted 14 compounds with high binding energies to the ATP-binding pocket of TaCDK7. Three compounds (cimicifugin, ST092793, and ST026925) of these 14 compounds were non-cytotoxic to the uninfected bovine cells (BoMac cells). Cimicifugin treatment led to the activation of the extrinsic apoptosis pathway and induced autophagy in T. annulata-infected cells. Furthermore, cimicifugin also inhibited the growth of P. falciparum, indicating that it has both anti-theilerial and anti-malarial activities and that TaCDK7 and PfCDK7 are promising drug targets.

5.
Eur J Med Chem ; 276: 116677, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39024967

ABSTRACT

Emerging resistance to current antimalarials is reducing their effectiveness and therefore there is a need to develop new antimalarial therapies. Toward this goal, high throughput screens against the P. falciparum asexual parasite identified the pyrazolopyridine 4-carboxamide scaffold. Structure-activity relationship analysis of this chemotype defined that the N1-tert-butyl group and aliphatic foliage in the 3- and 6-positions were necessary for activity, while the inclusion of a 7'-aza-benzomorpholine on the 4-carboxamide motif resulted in potent anti-parasitic activity and increased aqueous solubility. A previous report that resistance to the pyrazolopyridine class is associated with the ABCI3 transporter was confirmed, with pyrazolopyridine 4-carboxamides showing an increase in potency against parasites when the ABCI3 transporter was knocked down. The low metabolic stability intrinsic to the pyrazolopyridine scaffold and the slow rate by which the compounds kill asexual parasites resulted in poor performance in a P. berghei asexual blood stage mouse model. Lowering the risk of resistance and mitigating the metabolic stability and cytochrome P450 inhibition will be challenges in the future development of the pyrazolopyrimidine antimalarial class.

6.
Sudan J Paediatr ; 24(1): 73-79, 2024.
Article in English | MEDLINE | ID: mdl-38952618

ABSTRACT

Multisystem inflammatory syndrome of childhood (MIS-C) is a recently described entity in pediatrics post-COVID-19 pandemic. Hemophagocytic lymphohistiocytosis (HLH) is a clinical syndrome caused by an unregulated proliferation of macrophages as well as T lymphocytes. Both entities can be considered overlapping, although distinct criteria for each can be found in the literature. Herein, we report a patient with MIS-C post-COVID-19 infection, complicated with HLH secondary to Plasmodium falciparum malaria from a blood transfusion.

7.
Mol Neurobiol ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023792

ABSTRACT

Although most children with cerebral malaria fully recover, more than a fifth of the survivors develop post-discharge neurodevelopmental sequelae suggestive of advanced neuronal injury. However, the cerebral molecular processes initiating neurological dysfunction in cerebral malaria are still debatable. In this article, we explore available data and hypothesise that cerebral malaria might be linked to APOE-mediated amyloidosis, one of the pathological processes associated with Alzheimer's disease. If our hypothesis is tested and found to be true, it could have far-reaching implications for what we know about cerebral malaria pathogenesis.

8.
Trends Parasitol ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39025766

ABSTRACT

In 2004 the first annual BioMalPar meeting was held at EMBL Heidelberg, bringing together researchers from around the world with the goal of building connections between malaria research groups in Europe. Twenty years on it is time to reflect on what was achieved and to look ahead to the future.

9.
Front Immunol ; 15: 1392043, 2024.
Article in English | MEDLINE | ID: mdl-38962015

ABSTRACT

In the Americas, P. vivax is the predominant causative species of malaria, a debilitating and economically significant disease. Due to the complexity of the malaria parasite life cycle, a vaccine formulation with multiple antigens expressed in various parasite stages may represent an effective approach. Based on this, we previously designed and constructed a chimeric recombinant protein, PvRMC-1, composed by PvCyRPA, PvCelTOS, and Pvs25 epitopes. This chimeric protein was strongly recognized by naturally acquired antibodies from exposed population in the Brazilian Amazon. However, there was no investigation about the induced immune response of PvRMC-1. Therefore, in this work, we evaluated the immunogenicity of this chimeric antigen formulated in three distinct adjuvants: Stimune, AddaVax or Aluminum hydroxide (Al(OH)3) in BALB/c mice. Our results suggested that the chimeric protein PvRMC-1 were capable to generate humoral and cellular responses across all three formulations. Antibodies recognized full-length PvRMC-1 and linear B-cell epitopes from PvCyRPA, PvCelTOS, and Pvs25 individually. Moreover, mice's splenocytes were activated, producing IFN-γ in response to PvCelTOS and PvCyRPA peptide epitopes, affirming T-cell epitopes in the antigen. While aluminum hydroxide showed notable cellular response, Stimune and Addavax induced a more comprehensive immune response, encompassing both cellular and humoral components. Thus, our findings indicate that PvRMC-1 would be a promising multistage vaccine candidate that could advance to further preclinical studies.


Subject(s)
Antibodies, Protozoan , Antigens, Protozoan , Malaria Vaccines , Malaria, Vivax , Mice, Inbred BALB C , Plasmodium vivax , Protozoan Proteins , Animals , Plasmodium vivax/immunology , Plasmodium vivax/genetics , Mice , Antigens, Protozoan/immunology , Antigens, Protozoan/genetics , Malaria, Vivax/immunology , Malaria, Vivax/prevention & control , Antibodies, Protozoan/immunology , Malaria Vaccines/immunology , Female , Protozoan Proteins/immunology , Protozoan Proteins/genetics , Epitopes, B-Lymphocyte/immunology , Epitopes, B-Lymphocyte/genetics , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/genetics , Disease Models, Animal , Adjuvants, Immunologic , Immunogenicity, Vaccine , Antigens, Surface
10.
Gene ; 927: 148744, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-38964492

ABSTRACT

Current understanding of genetic polymorphisms and natural selection in Plasmodium falciparum circumsporozoite (PfCSP), the leading malaria vaccine, is crucial for the development of next-generation vaccines, and such data is lacking in Africa. Blood samples were collected among Plasmodium-infected individuals living in four Cameroonian areas (Douala, Maroua, Mayo-Oulo, Pette). DNA samples were amplified using nested PCR protocols, sequenced, and BLASTed. Single nucleotide polymorphisms (SNPs) were analysed in each PfCSP region, and their impact on PfCSP function/structure was predicted in silico. The N-terminal region showed a limited polymorphism with four haplotypes, and three novel SNPs (N68Y, R87W, K93E) were found. Thirty-five haplotypes were identified in the central region, with several variants (e.g., NVNP and KANP). The C-terminal region was also highly diverse, with 25 haplotypes and eight novel SNPs (N290D, N308I, S312G, K317A, V344I, D356E, E357L, D359Y). Most polymorphic codon sites were mainly observed in the Th2R subregion in isolates from Douala and Pette. The codon site 321 was under episodic positive selection. One novel (E357L) and three known (K322I, G349D, D359Y) SNPs show an impact on function/structure. This study showed extensive genetic diversity with geographical patterns and evidence of the selection of Cameroonian PfCSP central and C-terminal regions.


Subject(s)
Haplotypes , Malaria Vaccines , Malaria, Falciparum , Plasmodium falciparum , Polymorphism, Single Nucleotide , Protozoan Proteins , Plasmodium falciparum/genetics , Plasmodium falciparum/immunology , Cameroon , Protozoan Proteins/genetics , Humans , Malaria, Falciparum/parasitology , Malaria, Falciparum/prevention & control , Malaria Vaccines/genetics , Malaria Vaccines/immunology
11.
Pan Afr Med J ; 47: 175, 2024.
Article in English | MEDLINE | ID: mdl-39036016

ABSTRACT

Introduction: in areas with intense perennial malaria transmission, limited data is available on the impact of environmental conditions especially rainfall on naturally acquired immunity against promising malaria vaccine candidates. For this reason, we have compared IgG antibody responses specific to Plasmodium spp. derived MSP3 and UB05 vaccine candidates, in plasma of children living in two areas of Cameroon differing in rainfall conditions. Methods: data about children less than 5 years old was collected during the years 2017 and 2018. Next malaria asymptomatic P. falciparum (Pf) infected children were selected following malaria test confirmation. MSP3 and UB05 specific IgG antibody responses were measured in participant´s plasma using enzyme-linked immunosorbent assay (ELISA). Results: interestingly, IgG antibody responses specific to UB05 were significantly higher (p<0.0001) in Pf-negative children when compared to their asymptomatic Pf-infected counterparts living in monomodal rainfall areas. In contrast, a significantly higher (p<0.0001) IgG response to MSP3 was observed instead in asymptomatic Pf-infected children in the same population. In addition, IgG responses specific to UB05 remained significantly higher in bimodal when compared to monomodal rainfall areas irrespective of children´s Pf infection status (p<0.0055 for Pf-positive and p<0.0001 for negative children). On the contrary, IgG antibody responses specific to MSP3 were significantly higher in bimodal relative to monomodal rainfall areas (P<0.0001) just for Pf-negative children. Conclusion: thus IgG antibody responses specific to UBO5 are a better correlate of naturally acquired immunity against malaria in Pf-negative Cameroonian children especially in monomodal rainfall areas.


Subject(s)
Antibodies, Protozoan , Antigens, Protozoan , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G , Malaria, Falciparum , Plasmodium falciparum , Protozoan Proteins , Humans , Cameroon , Malaria, Falciparum/immunology , Malaria, Falciparum/epidemiology , Immunoglobulin G/blood , Child, Preschool , Plasmodium falciparum/immunology , Protozoan Proteins/immunology , Antigens, Protozoan/immunology , Antibodies, Protozoan/blood , Infant , Female , Malaria Vaccines/administration & dosage , Malaria Vaccines/immunology , Male , Rain , Recombinant Proteins/immunology
12.
J Infect Dis ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38979599

ABSTRACT

BACKGROUND: The Dantu blood group variant protects against P. falciparum infections but its wider consequences have not been previously explored. Here, we investigate the impact of Dantu on susceptibility to bacteraemia. METHODS: We conducted a case-control study in children presenting with community-acquired bacteraemia to Kilifi County Hospital in Kenya between 1998 and 2010. We used logistic regression to test for associations between the Dantu marker SNP rs186873296 A>G and both all-cause and pathogen-specific bacteraemia under an additive model. We used date of admission as a proxy measure of malaria transmission intensity, given known differences in malaria prevalence over the course of the study. RESULTS: Dantu was associated with protection from all-cause bacteraemia (OR=0.81, p=0.014), the association being greatest in homozygotes (OR=0.30, p=0.013). This protection was shared across the major bacterial pathogens but, notably, was only significant during the era of high malaria-transmission pre-2003 (OR=0.79, p=0.023). CONCLUSIONS: Consistent with previous studies showing the indirect impact on bacteraemia risk of other malaria-associated red cell variants, our study also shows that Dantu is protective against bacteraemia via its effect on malaria risk. Dantu does not appear to be under balancing selection through an increased risk of bacterial infections.

13.
HardwareX ; 19: e00540, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38988372

ABSTRACT

Recently, a novel method for the growth inhibition of malaria parasites using microwaves was proposed. However, the apparatuses used to demonstrate this method are high-cost and immovable, hindering the progression in this field of research, which is still in its early stages. This paper presents the redesign, construction, and validation of an equivalent system, converting it into a portable and low-cost system, capable of replacing the existing one. The proposed system is mainly composed of an RF generator (MAX2870), an RF amplifier (SKYWORKS 66292-11) and a graphical user interface. Likewise, the RF applicator proposed by the original study was redesigned, resulting in a five-fold improvement in return loss. The obtained results indicate that the proposed system achieves 90% parasite growth inhibition, matching the performance of its counterpart at less than 1% of its cost. These results represent a breakthrough for the creation of smaller, enhanced devices that open new possibilities for an alternative treatment to combat this devastating disease.

14.
In Silico Pharmacol ; 12(2): 60, 2024.
Article in English | MEDLINE | ID: mdl-38978708

ABSTRACT

This study aimed to repurpose Drug Bank Compounds against P. falciparum Dihydroorotate dehydrogenase (Pf-DHODH)a potential molecular target for antimalarial drug development due to its vital role in P. falciparum survival. Initially, the MATGEN server was used to screen drugs against Pf-DHODH (PDB ID 6GJG), followed by revalidating the results through docking by Autodock Vina through PyRx. Based on the docking results, three drugs namely, Talnifumate, Sulfaphenazole, and (3S)-N-[(2S)-1-[2-(1H-indol-3-yl)ethylamino]-1-oxopropan-2-yl]-1-(4-methoxyphenyl)-5-oxopyrrolidine-3-carboxamide-were subjected to molecular dynamics simulation for 100 ns. Molecular dynamics simulation results indicate that (3S)-N-[(2S)-1-[2-(1H-indol-3-yl)ethylamino]-1-oxopropan-2-yl]-1-(4-methoxyphenyl)-5-oxopyrrolidine-3-carboxamide- and Sulfaphenazole may target Pf-DHODH by forming a stable protein-ligand complex as they showed better free binding energy -130.58 kJ/mol, and -79.84 kJ/mol, respectively as compared to the free binding energy 116.255 kJ/mol of the reference compound; 3,6-dimethyl- ~ {N}-[4-(trifluoromethyl)phenyl]-[1,2]oxazolo[5,4-d]pyrimidin-4-amine. Although the studied compounds are drugs, still we applied Lipinski's rules and ADMET analysis that reconfirmed that these drugs have favorable drug-like properties. In conclusion, the results of the study show that Talniflumate and Sulfaphenazole may be potential antimalarial drug candidates.The derivatives of these drugs could be designed and tested to develop better drugs against Plasmodium species.

15.
Cureus ; 16(6): e61862, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38978931

ABSTRACT

Malaria is an infectious disease caused by several types of parasitic plasmodia and transmitted to humans through Anopheles mosquitoes. The disease has long been widespread and has caused a significant number of deaths and decreased life quality from sequelae worldwide. As understanding of the disease increased immensely at the beginning of the 20th century, eradication plans were implemented to decrease disease transmission. This led to the successful eradication of malaria across predominantly industrialized countries, with multiple geographic areas remaining malaria endemic zones to this day. With climate changes and migration, the risk of reintroduction of malaria to malaria-free zones has risen due to relatively easy travel to endemic zones and importation of cases. On the one hand, this is a significant public health risk and, on the other, a challenge to the medical system, as healthcare workers in malaria-free zones are often ill-prepared to recognize, diagnose, and treat malaria cases. Herein, we present an autopsy and histopathology case report of tropical (falciparum) malaria, complicated with blackwater fever (malignant malaria) with prevalent gross and histopathological changes, including hemomelanin deposition in the spline, liver, and bone marrow; visible parasitic forms in the remaining red blood cells; Durk's granulomas, sludge, and petechial hemorrhages in the central nervous system; and hemoglobin casts within the renal tubular structures. We also discuss the history and risk of reintroducing malaria into a malaria-free zone - Bulgaria.

16.
PeerJ ; 12: e17632, 2024.
Article in English | MEDLINE | ID: mdl-38948214

ABSTRACT

Background: The integration of diagnostic methods holds promise for advancing the surveillance of malaria transmission in both endemic and non-endemic regions. Serological assays emerge as valuable tools to identify and delimit malaria transmission, serving as a complementary method to rapid diagnostic tests (RDT) and thick smear microscopy. Here, we evaluate the potential of antibodies directed against peptides encompassing the entire amino acid sequence of the PvMSP-1 Sal-I strain as viable serological biomarkers for P. vivax exposure. Methods: We screened peptides encompassing the complete amino acid sequence of the Plasmodium vivax Merozoite Surface Protein 1 (PvMSP-1) Sal-I strain as potential biomarkers for P. vivax exposure. Here, immunodominant peptides specifically recognized by antibodies from individuals infected with P. vivax were identified using the SPOT-synthesis technique followed by immunoblotting. Two 15-mer peptides were selected based on their higher and specific reactivity in immunoblotting assays. Subsequently, peptides p70 and p314 were synthesized in soluble form using SPPS (Solid Phase Peptide Synthesis) and tested by ELISA (IgG, and subclasses). Results: This study unveils the presence of IgG antibodies against the peptide p314 in most P. vivax-infected individuals from the Brazilian Amazon region. In silico B-cell epitope prediction further supports the utilization of p314 as a potential biomarker for evaluating malaria transmission, strengthened by its amino acid sequence being part of a conserved block of PvMSP-1. Indeed, compared to patients infected with P. falciparum and uninfected individuals never exposed to malaria, P. vivax-infected patients have a notably higher recognition of p314 by IgG1 and IgG3.


Subject(s)
Antibodies, Protozoan , Biomarkers , Malaria, Vivax , Merozoite Surface Protein 1 , Plasmodium vivax , Humans , Malaria, Vivax/immunology , Malaria, Vivax/blood , Malaria, Vivax/parasitology , Malaria, Vivax/transmission , Malaria, Vivax/diagnosis , Merozoite Surface Protein 1/immunology , Plasmodium vivax/immunology , Biomarkers/blood , Antibodies, Protozoan/immunology , Antibodies, Protozoan/blood , Immunoglobulin G/immunology , Immunoglobulin G/blood , Adult , Female , Male , Middle Aged , Peptides/immunology , Enzyme-Linked Immunosorbent Assay/methods , Young Adult , Adolescent , Amino Acid Sequence
17.
Int Marit Health ; 75(2): 103-108, 2024.
Article in English | MEDLINE | ID: mdl-38949218

ABSTRACT

BACKGROUND: The World Health Organization (WHO) reported an estimated 249 million malaria cases globally in 2023, of which 94% were reported from Africa. Tanzania, a Sub-Saharan African country, has an exceptionally high malaria prevalence (3.6 million in 2023). The aim of the present study was to assess malaria prevalence rates in the Arusha Region, northern Tanzania. This region is famous for its national parks and wildlife reserves, and it is visited by thousands of tourists from all over the world each year. The assessment of malaria prevalence in the region is important in the context of the necessity to administer antimalarial chemoprophylaxis to international travellers. MATERIAL AND METHODS: The study group consisted of 101 people, residents of the Karatu District in the Arusha Region, aged between 1 and 73 years, who volunteered to participate in the screening. Phase I of the study was conducted in July 2022 in the Karatu Lutheran Hospital in Karatu Town (located close to the Ngorongoro Conservation Area and the Serengeti National Park). During this phase a venous blood sample was collected from each patient. The samples were tested for malaria using a rapid diagnostic test (mRDT); the same samples were also used to measure haemoglobin concentration and next they were applied onto the Whatman FTA micro cards for further molecular diagnostics in Poland (phase II). RESULTS: mRDT detected two (2.0%) infections caused by Plasmodium (the etiological factor of malaria), the molecular tests (RT-PCR) confirmed the two positive results by mRDT but also detected infections in six other samples (7.9% in total). The study found that six patients were infected with the Plasmodium falciparum species, while two other subjects had co-infections (P. falciparum + P. ovale, P. falciparum + P. vivax + P. malariae). CONCLUSIONS: The study findings confirm the prevalence of malaria in areas located close to national parks in northern Tanzania and support the use of antimalarial chemoprophylaxis in international travellers visiting the area. The present study found co-infections caused by four different species of Plasmodium species which supports the prevalence of different parasitic species in Sub-Saharan Africa and is in line with CDC reports but contrary to WHO reports which estimate that 100% of malaria cases in Sub-Saharan Africa are caused by P. falciparum.


Subject(s)
Malaria , Humans , Tanzania/epidemiology , Prevalence , Adult , Middle Aged , Adolescent , Male , Female , Child , Aged , Young Adult , Child, Preschool , Malaria/epidemiology , Infant , Antimalarials/therapeutic use
18.
J Infect Dis ; 230(1): 263-270, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39052743

ABSTRACT

Pathogens such as Plasmodium, Babesia, and Theileria invade and multiply within host red blood cells, leading to the pathological consequences of malaria, babesiosis, and theileriosis. Establishing continuous in vitro culture systems and suitable animal models is crucial for studying these pathogens. This review spotlights the Babesia duncani in culture-in mouse (ICIM) model as a promising resource for advancing research on the biology, pathogenicity, and virulence of intraerythrocytic parasites. The model offers practical benefits, encompassing well-defined culture conditions, ease of manipulation, and a well-annotated genome. Moreover, B. duncani serves as a surrogate system for drug discovery, facilitating the evaluation of new antiparasitic drugs in vitro and in animals, elucidating their modes of action, and uncovering potential resistance mechanisms. The B. duncani ICIM model thus emerges as a multifaceted tool with profound implications, promising advancements in our understanding of parasitic biology and shaping the development of future therapies.


Subject(s)
Babesia , Babesiosis , Disease Models, Animal , Erythrocytes , Animals , Babesia/drug effects , Babesia/genetics , Erythrocytes/parasitology , Mice , Babesiosis/drug therapy , Babesiosis/parasitology , Antiparasitic Agents/therapeutic use , Antiparasitic Agents/pharmacology , Humans , Virulence
19.
Infect Genet Evol ; : 105643, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39053565

ABSTRACT

Plasmodium vivax, traditionally overlooked has experienced a notable increase in cases in East Africa. This study investigated the geographical origin and genetic diversity of P. vivax in Sudan using 14 microsatellite markers. A total of 113 clinical P. vivax samples were collected from two different ecogeographical zones, New Halfa and Khartoum, in Sudan. Additionally, 841 geographical samples from the database were incorporated for a global genetic analysis to discern genetic relationships among P. vivax isolates on regional and worldwide scales. On the regional scale, our findings revealed 91 unique and 8 shared haplotypes among the Sudan samples, showcasing a remarkable genetic diversity compared to other geographical isolates and supporting the hypothesis that P. vivax originated from Africa. On a global scale, distinct genetic clustering of P. vivax isolates from Africa, South America, and Asia (including Papua New Guinea and Solomon Island) was observed, with limited admixture among the three clusters. Principal component analysis emphasized the substantial contribution of African isolates to the observed global genetic variation. The Sudanese populations displayed extensive genetic diversity, marked by significant multi-locus linkage disequilibrium, suggesting an ancestral source of P. vivax variation globally and frequent recombination among the isolates. Notably, the East African P. vivax exhibited similarity with some Asian isolates, indicating potential recent introductions. Overall, our results underscore the effectiveness of utilizing microsatellite markers for implementing robust control measures, given their ability to capture extensive genetic diversity and linkage disequilibrium patterns.

20.
Sci Rep ; 14(1): 16901, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39043812

ABSTRACT

Malaria transmission and endemicity in Africa remains hugely disproportionate compared to the rest of the world. The complex life cycle of P. falciparum (Pf) between the vertebrate human host and the anopheline vector results in differential expression of genes within and between hosts. An in-depth understanding of Pf interaction with various human genes through regulatory elements will pave way for identification of newer tools in the arsenal for malaria control. Therefore, the regulatory elements (REs) involved in the over- or under-expression of various host immune genes hold the key to elucidating alternative control measures that can be applied for disease surveillance, prompt diagnosis and treatment. We carried out an RNAseq analysis to identify differentially expressed genes and network elucidation of non-coding RNAs and target genes associated with immune response in individuals with different clinical outcomes. Raw RNAseq datasets, retrieved for analyses include individuals with severe (Gambia-20), symptomatic (Burkina Faso-15), asymptomatic (Mali-16) malaria as well as uninfected controls (Tanzania-20; Mali-36). Of the total 107 datasets retrieved, we identified 5534 differentially expressed genes (DEGs) among disease and control groups. A peculiar pattern of DEGs was observed, with individuals presenting with severe/symptomatic malaria having the highest and most diverse upregulated genes, while a reverse phenomenon was recorded among asymptomatic and uninfected individuals. In addition, we identified 141 differentially expressed micro RNA (miRNA), of which 78 and 63 were upregulated and downregulated respectively. Interactome analysis revealed a moderate interaction between DEGs and miRNAs. Of all identified miRNA, five were unique (hsa-mir-32, hsa-mir-25, hsa-mir-221, hsa-mir-29 and hsa-mir-148) because of their connectivity to several genes, including hsa-mir-221 connected to 16 genes. Six-hundred and eight differentially expressed long non coding RNA (lncRNA) were also identified, including SLC7A11, LINC01524 among the upregulated ones. Our study provides important insight into host immune genes undergoing differential expression under different malaria conditions. It also identified unique miRNAs and lncRNAs that modify and/or regulate the expression of various immune genes. These regulatory elements we surmise, have the potential to serve a diagnostic purpose in discriminating between individuals with severe/symptomatic malaria and those with asymptomatic infection or uninfected, following further clinical validation from field isolates.


Subject(s)
Gene Expression Profiling , MicroRNAs , RNA, Long Noncoding , Humans , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Gene Expression Profiling/methods , Malaria, Falciparum/genetics , Malaria, Falciparum/parasitology , Transcriptome , Plasmodium falciparum/genetics , Gene Expression Regulation , Asymptomatic Infections , Gene Regulatory Networks , Malaria/genetics , Malaria/parasitology
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