-
Parasites & Vectors Apr 2018In the field of archaeological parasitology, researchers have long documented the distribution of parasites in archaeological time and space through the analysis of... (Review)
Review
In the field of archaeological parasitology, researchers have long documented the distribution of parasites in archaeological time and space through the analysis of coprolites and human remains. This area of research defined the origin and migration of parasites through presence/absence studies. By the end of the 20th century, the field of pathoecology had emerged as researchers developed an interest in the ancient ecology of parasite transmission. Supporting studies were conducted to establish the relationships between parasites and humans, including cultural, subsistence, and ecological reconstructions. Parasite prevalence data were collected to infer the impact of parasitism on human health. In the last few decades, a paleoepidemiological approach has emerged with a focus on applying statistical techniques for quantification. The application of egg per gram (EPG) quantification methods provide data about parasites' prevalence in ancient populations and also identify the pathological potential that parasitism presented in different time periods and geographic places. Herein, we compare the methods used in several laboratories for reporting parasite prevalence and EPG quantification. We present newer quantification methods to explore patterns of parasite overdispersion among ancient people. These new methods will be able to produce more realistic measures of parasite infections among people of the past. These measures allow researchers to compare epidemiological patterns in both ancient and modern populations.
Topics: Animals; Archaeology; Feces; Fossils; Humans; Mummies; Parasites; Parasitology
PubMed: 29661215
DOI: 10.1186/s13071-018-2729-4 -
International Journal For Parasitology Dec 2021In the five decades since the first publication of the International Journal for Parasitology, ecological parasitology has grown from modest beginnings to become a... (Review)
Review
In the five decades since the first publication of the International Journal for Parasitology, ecological parasitology has grown from modest beginnings to become a modern discipline with a strong theoretical foundation, a diverse toolkit, and a multidisciplinary approach. In this review, I highlight 12 advances in the field that have spurred its growth over the past 50 years. Where relevant, I identify pivotal contributions that have altered the course of research, as well as the influence of developments in other fields such as mainstream ecology and molecular biology. The 12 key advances discussed are in areas including parasite population dynamics and community assembly, the regulation of host population abundance and food web structure, parasites as agents of natural selection, the impacts of biodiversity and anthropogenic changes on host-parasite interactions, the biogeography of parasite diversity, and the evolutionary genetics of parasites. I conclude by identifying some challenges and opportunities lying ahead, which need to be met for the future growth of ecological research on host-parasite interactions.
Topics: Animals; Biodiversity; Biological Evolution; Host-Parasite Interactions; Parasites; Parasitology
PubMed: 34390744
DOI: 10.1016/j.ijpara.2021.07.001 -
Current Opinion in Microbiology Feb 2015Parasites, defined as eukaryotic microbes and parasitic worms that cause global diseases of human and veterinary importance, span many lineages in the eukaryotic Tree of... (Review)
Review
Parasites, defined as eukaryotic microbes and parasitic worms that cause global diseases of human and veterinary importance, span many lineages in the eukaryotic Tree of Life. Historically challenging to study due to their complicated life-cycles and association with impoverished settings, their inherent complexities are now being elucidated by genome sequencing. Over the course of the last decade, projects in large sequencing centers, and increasingly frequently in individual research labs, have sequenced dozens of parasite reference genomes and field isolates from patient populations. This 'tsunami' of genomic data is answering questions about parasite genetic diversity, signatures of evolution orchestrated through anti-parasitic drug and host immune pressure, and the characteristics of populations. This brief review focuses on the state of the art of parasitic protist genomics, how the peculiar genomes of parasites are driving creative methods for their sequencing, and the impact that next-generation sequencing is having on our understanding of parasite population genomics and control of the diseases they cause.
Topics: Animals; Evolution, Molecular; Genetic Variation; Genetics, Population; Genomics; Humans; Parasites; Parasitic Diseases
PubMed: 25461572
DOI: 10.1016/j.mib.2014.11.001 -
PLoS Neglected Tropical Diseases Aug 2021Protozoan parasites are responsible for severe disease and suffering in humans worldwide. Apart from disease transmission via insect vectors and contaminated soil, food,... (Review)
Review
Protozoan parasites are responsible for severe disease and suffering in humans worldwide. Apart from disease transmission via insect vectors and contaminated soil, food, or water, transmission may occur congenitally or by way of blood transfusion and organ transplantation. Several recent outbreaks associated with fresh produce and potable water emphasize the need for vigilance and monitoring of protozoan parasites that cause severe disease in humans globally. Apart from the tropical parasite Plasmodium spp., other protozoa causing debilitating and fatal diseases such as Trypanosoma spp. and Naegleria fowleri need to be studied in more detail. Climate change and socioeconomic issues such as migration continue to be major drivers for the spread of these neglected tropical diseases beyond endemic zones. Due to the complex life cycles of protozoa involving multiple hosts, vectors, and stringent growth conditions, studying these parasites has been challenging. While in vivo models may provide insights into host-parasite interaction, the ethical aspects of laboratory animal use and the challenge of ready availability of parasite life stages underline the need for in vitro models as valid alternatives for culturing and maintaining protozoan parasites. To our knowledge, this review is the first of its kind to highlight available in vitro models for protozoa causing highly infectious diseases. In recent years, several research efforts using new technologies such as 3D organoid and spheroid systems for protozoan parasites have been introduced that provide valuable tools to advance complex culturing models and offer new opportunities toward the advancement of parasite in vitro studies. In vitro models aid scientists and healthcare providers in gaining insights into parasite infection biology, ultimately enabling the use of novel strategies for preventing and treating these diseases.
Topics: Animals; Host-Parasite Interactions; Humans; Life Cycle Stages; Parasitic Diseases; Parasitology; Plasmodium; Trypanosoma
PubMed: 34437538
DOI: 10.1371/journal.pntd.0009668 -
Acta Parasitologica Mar 2024As a result of environmental imbalances of anthropogenic origin, the potential for transmission of parasites and viruses between different primates, including humans,... (Review)
Review
PURPOSE
As a result of environmental imbalances of anthropogenic origin, the potential for transmission of parasites and viruses between different primates, including humans, might increase. Thus, parasitic studies have great relevance to primatology, which motivated us to conduct a literature review to synthesize the information available in American primates of the Callithrix genus.
METHODS
We carried out the bibliographic search on the main groups of parasites (protozoa, helminths, arthropods, ectoparasites) and viruses found in Callithrix in Brazil in search platforms and consider all manuscript that appeared in search engines, published between the years 1910 and December 2022. In each selected article, the following information was recorded: the host species; parasite taxa; scientific classification of the parasite; host habitat (free-living, captive); diagnostic technique; state; and bibliographic reference. Data were tabulated and arranged in a parasite-host table.
RESULTS
Some endemic genera, such as Callithrix, are widely distributed geographically across Brazil and have characteristics of adaptation to different habitats due to their flexibility in diet and behavior. These factors can make them subject to a greater diversity of parasites and viruses in the country. Here, we identified 68 parasitic taxa, belonging to the clades protozoa (n = 22), helminths (n = 34), ectoparasites (n = 7), and viruses (n = 5). Out of this total, 19 have zoonotic potential. Of the six existing marmoset species, Callithrix jacchus was the most frequent in studies, and Callithrix flaviceps did not have reports. All regions of the country had occurrences, mainly the Southeast, where 54% of the cases were reported. In 46% of the reported parasites and viruses, it was not possible to identify the corresponding species.
CONCLUSION
We conclude that in part of the works the identification methods are not being specific, which makes it difficult to identify the species that affects Callithrix spp. Furthermore, the studies present geographic disparities, being concentrated in the southeast of the country, making it impossible to have a more uniform analysis of the findings. Thus, it is observed that information about parasites and viruses is incipient in the genus Callithrix in Brazil.
Topics: Animals; Brazil; Callithrix; Parasites; Monkey Diseases; Viruses; Virus Diseases; Parasitic Diseases, Animal
PubMed: 38184509
DOI: 10.1007/s11686-023-00766-y -
Molecular and Biochemical Parasitology 2016Parasite genomes typically contain unique contingency gene families encoding multi-copy effector proteins that are often expressed abundantly on the parasite cell... (Review)
Review
Parasite genomes typically contain unique contingency gene families encoding multi-copy effector proteins that are often expressed abundantly on the parasite cell surface and beyond. The functions of these gene families are incompletely understood but it is clear that they perform fundamental roles at the host-parasite interface. Over evolutionary timescales, the evolution of these gene families is likely to have decisive effects on the pathology and virulence of parasitic infections. In this review, I will compare the evolutionary dynamics of multiple examples from trypanosomatids and apicomplexan parasites to demonstrate how their inherent mutability makes their phylogeny very different to 'normal' gene families. I will argue that phylogenetic analyses could help to understand the functions of these enigmatic genes.
Topics: Animals; Biological Evolution; Cell Surface Extensions; Evolution, Molecular; Genes, Protozoan; Multigene Family; Parasites; Phylogeny
PubMed: 27012486
DOI: 10.1016/j.molbiopara.2016.03.007 -
Trends in Parasitology Mar 2024Nematodes, a diverse group of roundworms, exhibit a wide range of dietary habits, including parasitism of animals and plants. These parasites cause substantial economic... (Review)
Review
Nematodes, a diverse group of roundworms, exhibit a wide range of dietary habits, including parasitism of animals and plants. These parasites cause substantial economic losses in agriculture and pose significant health challenges to humans and animals. This review explores the unique adaptations of parasitic nematodes, emphasizing their nutritional requirements and metabolic dependencies. Recent research has identified cross-kingdom compartmentalization of vitamin B5 biosynthesis in some parasitic nematodes, shedding light on coevolutionary dynamics and potential targets for control strategies. Several open questions remain regarding the complexity of nematode nutrition, host manipulation, evolutionary adaptations, and the influence of environmental factors on their metabolic processes. Understanding these aspects offers promising avenues for targeted interventions to manage and control these economically and medically important parasites.
Topics: Animals; Humans; Nematoda; Plants; Parasites; Agriculture; Feeding Behavior
PubMed: 38262837
DOI: 10.1016/j.pt.2023.12.013 -
Methods in Molecular Biology (Clifton,... 2022The pathogenesis of malaria is largely attributable to the parasite's ability to modulate its cytoadhesion phenotype. This relates to the multigenic families comprising...
The pathogenesis of malaria is largely attributable to the parasite's ability to modulate its cytoadhesion phenotype. This relates to the multigenic families comprising dozens to hundreds of members, whose expression, often mutually exclusive, allows the parasite to vary its adhesive properties and antigenic appearance. This phenomenon is mainly described for the variant surface antigens that the parasite expresses on the infected erythrocyte. In order to decipher these gene expression spectra and identify potential antigenic candidates and/or targets of therapeutic interest, the analysis of the transcriptomes of the parasites directly isolated from patients with well-defined clinical presentation is important. RNA stabilization is an absolute prerequisite for a precise and accurate transcriptome profiling. Immediate stabilization of RNA of biological samples is therefore necessary to prevent degradation by ribonucleases (RNase) or cellular changes. This chapter described methodology for preserving parasite RNA samples from malaria patients in the field for transcriptome studies.
Topics: Animals; Antigens; Erythrocytes; Malaria; Malaria, Falciparum; Parasites; Plasmodium falciparum; RNA
PubMed: 35881335
DOI: 10.1007/978-1-0716-2189-9_3 -
Parasitology Sep 2019The investigation of the glycan repertoire of several organisms has revealed a wide variation in terms of structures and abundance of glycan moieties. Among the... (Review)
Review
The investigation of the glycan repertoire of several organisms has revealed a wide variation in terms of structures and abundance of glycan moieties. Among the parasites, it is possible to observe different sets of glycoconjugates across taxa and developmental stages within a species. The presence of distinct glycoconjugates throughout the life cycle of a parasite could relate to the ability of that organism to adapt and survive in different hosts and environments. Carbohydrates on the surface, and in excretory-secretory products of parasites, play essential roles in host-parasite interactions. Carbohydrate portions of complex molecules of parasites stimulate and modulate host immune responses, mainly through interactions with specific receptors on the surface of dendritic cells, leading to the generation of a pattern of response that may benefit parasite survival. Available data reviewed here also show the frequent aspect of parasite immunomodulation of mammalian responses through specific glycan interactions, which ultimately makes these molecules promising in the fields of diagnostics and vaccinology.
Topics: Animals; Diagnostic Tests, Routine; Glycoconjugates; Host-Parasite Interactions; Life Cycle Stages; Parasites; Parasitic Diseases; Vaccines
PubMed: 31057132
DOI: 10.1017/S0031182019000465 -
Trends in Parasitology Dec 2019Trait-based research holds high potential to unveil ecological and evolutionary processes. Functional traits are fitness-related characteristics of individuals, which... (Review)
Review
Trait-based research holds high potential to unveil ecological and evolutionary processes. Functional traits are fitness-related characteristics of individuals, which are measured at individual level and defined without using information external to the individual. Despite the usefulness of the functional approach to understand the performance of individuals in ecosystems, and parasitism being the most common life-history strategy on Earth, studies based on functional traits of parasites are still scarce. Since the choice of functional traits is a critical step for any study, we propose a core list of seven functional traits of metazoan parasites, related to three universal challenges faced by organisms (dispersal, establishment, and persistence), and give guidelines to define appropriate functional traits in future parasite community studies.
Topics: Animals; Ecosystem; Host-Parasite Interactions; Life Cycle Stages; Life History Traits; Models, Biological; Parasites; Parasitology
PubMed: 31678065
DOI: 10.1016/j.pt.2019.09.003