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Cold Spring Harbor Perspectives in... Jan 2018In the mosquito-human life cycle, the six species of malaria parasites infecting humans (, , , , , and ) undergo 10 or more morphological states, replicate from single... (Review)
Review
In the mosquito-human life cycle, the six species of malaria parasites infecting humans (, , , , , and ) undergo 10 or more morphological states, replicate from single to 10,000+ cells, and vary in total population from one to many more than 10 organisms. In the human host, only a small number of these morphological stages lead to clinical disease and the vast majority of all malaria-infected patients in the world produce few (if any) symptoms in the human. Human clinical disease (e.g., fever, anemia, coma) is the result of the parasite preprogrammed biology in concert with the human pathophysiological response. Caveats and corollaries that add variation to this host-parasite interaction include parasite genetic diversity of key proteins, coinfections, comorbidities, delays in treatment, human polymorphisms, and environmental determinants.
Topics: Female; Humans; Malaria; Malaria, Cerebral; Placenta; Plasmodium; Pregnancy; Species Specificity; Virulence Factors
PubMed: 28533315
DOI: 10.1101/cshperspect.a025569 -
Medical Sciences (Basel, Switzerland) Dec 2022In sub-Saharan Africa, malaria is a leading cause of mortality and morbidity. As a result of the interplay between many factors, the control of this disease can be... (Review)
Review
In sub-Saharan Africa, malaria is a leading cause of mortality and morbidity. As a result of the interplay between many factors, the control of this disease can be challenging. However, few studies have demonstrated malaria's complexity, control, and modeling although this perspective could lead to effective policy recommendations. This paper aims to be a didactic material providing the reader with an overview of malaria. More importantly, using a system approach lens, we intend to highlight the debated topics and the multifaceted thematic aspects of malaria transmission mechanisms, while showing the control approaches used as well as the model supporting the dynamics of malaria. As there is a large amount of information on each subject, we have attempted to provide a basic understanding of malaria that needs to be further developed. Nevertheless, this study illustrates the importance of using a multidisciplinary approach to designing next-generation malaria control policies.
Topics: Humans; Malaria; Africa South of the Sahara; Policy; Mosquito Control
PubMed: 36649040
DOI: 10.3390/medsci11010003 -
Le Infezioni in Medicina Jun 2016Malaria, the most common parasitic disease in the world, is transmitted to the human host by mosquitoes of the genus Anopheles. The transmission of malaria requires the... (Review)
Review
Malaria, the most common parasitic disease in the world, is transmitted to the human host by mosquitoes of the genus Anopheles. The transmission of malaria requires the interaction between the host, the vector and the parasite.The four species of parasites responsible for human malaria are Plasmodium falciparum, Plasmodium ovale, Plasmodium malariae and Plasmodium vivax. Occasionally humans can be infected by several simian species, like Plasmodium knowlesi, recognised as a major cause of human malaria in South-East Asia since 2004. While P. falciparum is responsible for most malaria cases, about 8% of estimated cases globally are caused by P. vivax. The different Plasmodia are not uniformly distributed although there are areas of species overlap. The life cycle of all species of human malaria parasites is characterised by an exogenous sexual phase in which multiplication occurs in several species of Anopheles mosquitoes, and an endogenous asexual phase in the vertebrate host. The time span required for mature oocyst development in the salivary glands is quite variable (7-30 days), characteristic of each species and influenced by ambient temperature. The vector Anopheles includes 465 formally recognised species. Approximately 70 of these species have the capacity to transmit Plasmodium spp. to humans and 41 are considered as dominant vector capable of transmitting malaria. The intensity of transmission is dependent on the vectorial capacity and competence of local mosquitoes. An efficient system for malaria transmission needs strong interaction between humans, the ecosystem and infected vectors. Global warming induced by human activities has increased the risk of vector-borne diseases such as malaria. Recent decades have witnessed changes in the ecosystem and climate without precedent in human history although the emphasis in the role of temperature on the epidemiology of malaria has given way to predisposing conditions such as ecosystem changes, political instability and health policies that have reduced the funds for vector control, combined with the presence of migratory flows from endemic countries.
Topics: Animals; Anopheles; Climate; Climate Change; Disease Reservoirs; Endemic Diseases; Female; Global Health; Hominidae; Humans; Insect Vectors; Life Cycle Stages; Malaria; Plasmodium; Population Dynamics; Primate Diseases; Species Specificity; Urbanization
PubMed: 27367318
DOI: No ID Found -
The American Journal of Tropical... Jul 2018Important strides have been made within the past decade toward malaria elimination in many regions, and with this progress, the feasibility of eradication is once again... (Review)
Review
Important strides have been made within the past decade toward malaria elimination in many regions, and with this progress, the feasibility of eradication is once again under discussion. If the ambitious goal of eradication is to be achieved by 2040, all species of infecting humans will need to be targeted with evidence-based and concerted interventions. In this perspective, the potential barriers to achieving global malaria elimination are discussed with respect to the related diversities in host, parasite, and vector populations. We argue that control strategies need to be reorientated from a sequential attack on each species, dominated by to one that targets all species in parallel. A set of research themes is proposed to mitigate the potential setbacks on the pathway to a malaria-free world.
Topics: Animals; Anopheles; Antimalarials; Chloroquine; Disease Eradication; Host-Parasite Interactions; Humans; Malaria; Malaria, Falciparum; Malaria, Vivax; Mosquito Vectors; Plasmodium falciparum; Plasmodium knowlesi; Plasmodium malariae; Plasmodium ovale; Plasmodium vivax; Primaquine
PubMed: 29761762
DOI: 10.4269/ajtmh.17-0869 -
Advances in Parasitology 2021The zoonotic parasite Plasmodium knowlesi has emerged as an important cause of human malaria in parts of Southeast Asia. The parasite is indistinguishable by microscopy... (Review)
Review
The zoonotic parasite Plasmodium knowlesi has emerged as an important cause of human malaria in parts of Southeast Asia. The parasite is indistinguishable by microscopy from the more benign P. malariae, but can result in high parasitaemias with multiorgan failure, and deaths have been reported. Recognition of severe knowlesi malaria, and prompt initiation of effective therapy is therefore essential to prevent adverse outcomes. Here we review all studies reporting treatment of uncomplicated and severe knowlesi malaria. We report that although chloroquine is effective for the treatment of uncomplicated knowlesi malaria, artemisinin combination treatment is associated with faster parasite clearance times and lower rates of anaemia during follow-up, and should be considered the treatment of choice, particularly given the risk of administering chloroquine to drug-resistant P. vivax or P. falciparum misdiagnosed as P. knowlesi malaria in co-endemic areas. For severe knowlesi malaria, intravenous artesunate has been shown to be highly effective and associated with reduced case-fatality rates, and should be commenced without delay. Regular paracetamol may also be considered for patients with severe knowlesi malaria or for those with acute kidney injury, to attenuate the renal damage resulting from haemolysis-induced lipid peroxidation.
Topics: Antimalarials; Artesunate; Humans; Malaria; Malaria, Falciparum; Plasmodium knowlesi
PubMed: 34620385
DOI: 10.1016/bs.apar.2021.08.004 -
Lancet (London, England) Sep 2013Malaria-eliminating countries achieved remarkable success in reducing their malaria burdens between 2000 and 2010. As a result, the epidemiology of malaria in these... (Review)
Review
Malaria-eliminating countries achieved remarkable success in reducing their malaria burdens between 2000 and 2010. As a result, the epidemiology of malaria in these settings has become more complex. Malaria is increasingly imported, caused by Plasmodium vivax in settings outside sub-Saharan Africa, and clustered in small geographical areas or clustered demographically into subpopulations, which are often predominantly adult men, with shared social, behavioural, and geographical risk characteristics. The shift in the populations most at risk of malaria raises important questions for malaria-eliminating countries, since traditional control interventions are likely to be less effective. Approaches to elimination need to be aligned with these changes through the development and adoption of novel strategies and methods. Knowledge of the changing epidemiological trends of malaria in the eliminating countries will ensure improved targeting of interventions to continue to shrink the malaria map.
Topics: Adolescent; Adult; Africa South of the Sahara; Aged; Civilization; Cluster Analysis; Cross-Sectional Studies; Developing Countries; Emigration and Immigration; Female; Humans; Malaria; Malaria, Falciparum; Malaria, Vivax; Male; Middle Aged; Occupational Diseases; Plasmodium malariae; Plasmodium ovale; Population Dynamics; Young Adult
PubMed: 23594387
DOI: 10.1016/S0140-6736(13)60310-4 -
Frontiers in Immunology 2018Neutrophils are abundant in the circulation and are one of the immune system's first lines of defense against infection. There has been substantial work carried out... (Review)
Review
Neutrophils are abundant in the circulation and are one of the immune system's first lines of defense against infection. There has been substantial work carried out investigating the role of neutrophils in malaria and it is clear that during infection neutrophils are activated and are capable of clearing malaria parasites by a number of mechanisms. This review focuses on neutrophil responses to human malarias, summarizing evidence which helps us understand where neutrophils are, what they are doing, how they interact with parasites as well as their potential role in vaccine mediated immunity. We also outline future research priorities for these, the most abundant of leukocytes.
Topics: Animals; Antimalarials; Disease Models, Animal; Extracellular Traps; Humans; Leukocyte Count; Malaria; Malaria Vaccines; Neutrophil Activation; Neutrophils; Phagocytosis; Plasmodium; Reactive Oxygen Species
PubMed: 30619354
DOI: 10.3389/fimmu.2018.03005 -
Proceedings of the National Academy of... Oct 2020Asymptomatic carriers of parasites hamper malaria control and eradication. Achieving malaria eradication requires ultrasensitive diagnostics for low parasite density...
Asymptomatic carriers of parasites hamper malaria control and eradication. Achieving malaria eradication requires ultrasensitive diagnostics for low parasite density infections (<100 parasites per microliter blood) that work in resource-limited settings (RLS). Sensitive point-of-care diagnostics are also lacking for nonfalciparum malaria, which is characterized by lower density infections and may require additional therapy for radical cure. Molecular methods, such as PCR, have high sensitivity and specificity, but remain high-complexity technologies impractical for RLS. Here we describe a CRISPR-based diagnostic for ultrasensitive detection and differentiation of , , , and , using the nucleic acid detection platform SHERLOCK (specific high-sensitivity enzymatic reporter unlocking). We present a streamlined, field-applicable, diagnostic comprised of a 10-min SHERLOCK parasite rapid extraction protocol, followed by SHERLOCK for 60 min for species-specific detection via fluorescent or lateral flow strip readout. We optimized one-pot, lyophilized, isothermal assays with a simplified sample preparation method independent of nucleic acid extraction, and showed that these assays are capable of detection below two parasites per microliter blood, a limit of detection suggested by the World Health Organization. Our and assays exhibited 100% sensitivity and specificity on clinical samples (5 and 10 samples). This work establishes a field-applicable diagnostic for ultrasensitive detection of asymptomatic carriers as well as a rapid point-of-care clinical diagnostic for nonfalciparum malaria species and low parasite density infections.
Topics: Carrier State; Clustered Regularly Interspaced Short Palindromic Repeats; Diagnostic Techniques and Procedures; Genetic Techniques; Humans; Malaria; Plasmodium
PubMed: 32958655
DOI: 10.1073/pnas.2010196117 -
Bulletin of the World Health... 1974A global review of the problem of malaria accidentally transmitted by blood transfusion revealed that about 350 cases were reported during the period 1911-50 and 1756...
A global review of the problem of malaria accidentally transmitted by blood transfusion revealed that about 350 cases were reported during the period 1911-50 and 1756 during the period 1950-72. The great rise in the frequency of blood transfusions in medical practice and the increase of travel between countries in which malaria is absent and those where it is prevalent render transfusion malaria a problem of clinical and public health importance. Attention is drawn to the value of modern serological methods for the screening of blood donors.
Topics: Africa; Blood; Blood Donors; Chloroquine; Epidemiologic Methods; Fluorescent Antibody Technique; Humans; Immunity, Active; Iran; Malaria; Mexico; Plasmodium malariae; Romania; Spain; Time Factors; Transfusion Reaction; USSR; United Kingdom; United States; World Health Organization; Yugoslavia
PubMed: 4613511
DOI: No ID Found -
Malaria Journal Jul 2017In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an... (Review)
Review
In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.
Topics: Animals; Antimalarials; Brazil; Colombia; Disease Eradication; Health Policy; Humans; Incidence; Malaria; Peru; Plasmodium; Population Surveillance; Prevalence; Venezuela
PubMed: 28676055
DOI: 10.1186/s12936-017-1925-6