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Zoonoses and Public Health Feb 2020Captive and free-ranging wild bears can carry and transmit several zoonotic pathogens. A review of nearly 90 years of scientific publications concerning confirmed and... (Review)
Review
Captive and free-ranging wild bears can carry and transmit several zoonotic pathogens. A review of nearly 90 years of scientific publications concerning confirmed and potential zoonotic diseases that can be present in any of the eight species of bears in the world was conducted. The findings were organized amongst the following disease sections: bacterial, viral, protozoal, mycotic, helminth and arthropod-borne. The most commonly reported pathogens of concern were of parasitic (Trichinella, Toxoplasma) and bacterial (Francisella, Brucella) origin.
Topics: Animals; Animals, Wild; Animals, Zoo; Bacterial Infections; Humans; Parasitic Diseases, Animal; Ursidae
PubMed: 31828973
DOI: 10.1111/zph.12674 -
Parasites & Vectors Jun 2021Parasites, including viruses, bacteria, fungi, protists, helminths, and arthropods, are ubiquitous in the animal kingdom. Consequently, hosts are frequently infected... (Review)
Review
Parasites, including viruses, bacteria, fungi, protists, helminths, and arthropods, are ubiquitous in the animal kingdom. Consequently, hosts are frequently infected with more than one parasite species simultaneously. The assessment of such co-infections is of fundamental importance for disease ecology, but relevant studies involving non-domesticated animals have remained scarce. Many amphibians are in decline, and they generally have a highly diverse parasitic fauna. Here we review the literature reporting on field surveys, veterinary case studies, and laboratory experiments on co-infections in amphibians, and we summarize what is known about within-host interactions among parasites, which environmental and intrinsic factors influence the outcomes of these interactions, and what effects co-infections have on hosts. The available literature is piecemeal, and patterns are highly diverse, so that identifying general trends that would fit most host-multiparasite systems in amphibians is difficult. Several examples of additive, antagonistic, neutral, and synergistic effects among different parasites are known, but whether members of some higher taxa usually outcompete and override the effects of others remains unclear. The arrival order of different parasites and the time lag between exposures appear in many cases to fundamentally shape competition and disease progression. The first parasite to arrive can gain a marked reproductive advantage or induce cross-reaction immunity, but by disrupting the skin and associated defences (i.e., skin secretions, skin microbiome) and by immunosuppression, it can also pave the way for subsequent infections. Although there are exceptions, detrimental effects to the host are generally aggravated with increasing numbers of co-infecting parasite species. Finally, because amphibians are ectothermic animals, temperature appears to be the most critical environmental factor that affects co-infections, partly via its influence on amphibian immune function, partly due to its direct effect on the survival and growth of parasites. Besides their importance for our understanding of ecological patterns and processes, detailed knowledge about co-infections is also crucial for the design and implementation of effective wildlife disease management, so that studies concentrating on the identified gaps in our understanding represent rewarding research avenues.
Topics: Amphibians; Animals; Animals, Wild; Coinfection; Host-Parasite Interactions; Parasites; Parasitic Diseases, Animal
PubMed: 34082796
DOI: 10.1186/s13071-021-04796-1 -
Trends in Parasitology Mar 2023Imaging of parasites is central to diagnosis of many parasitic diseases and has thus far played an important role in the development of antiparasitic strategies. The... (Review)
Review
Imaging of parasites is central to diagnosis of many parasitic diseases and has thus far played an important role in the development of antiparasitic strategies. The development of novel imaging technologies has revolutionized medicine in fields other than parasitology and has also opened up new avenues for the visualization of parasites. Here we review the role imaging technology has played so far in parasitology and how it may spur further advancement. We point out possibilities to improve current microscopy-based diagnostic methods and how to extend them with radiological imaging modalities. We also highlight in vivo tracking of parasites as a readout for efficacy of new antiparasitic strategies and as a source of fundamental insights for rational design.
Topics: Animals; Humans; Parasitic Diseases; Parasites; Antiparasitic Agents; Diagnostic Imaging; Parasitology
PubMed: 36641293
DOI: 10.1016/j.pt.2022.12.008 -
Pediatrics International : Official... Mar 2021Japan has achieved significant improvements in the control and prevention of parasitic infections through a school-based approach since the 1930s. The use of chemical... (Review)
Review
Japan has achieved significant improvements in the control and prevention of parasitic infections through a school-based approach since the 1930s. The use of chemical fertilizers in agriculture, safe water and food, and improved sanitation and hygiene also contributed to the near eradication of endemic parasites. However, parasite infections continued to affect children mostly in resource-limited countries. The African continent has one of the highest burdens of such infections. The application of school-based approaches has several advantages where the structure of health-care systems is not optimal. In Africa, soil-transmitted helminths and schistosomiasis are frequently targets for school-based public health intervention. Mass drug administration by teachers at school can reach targeted children effectively and safely. The limitations of this approach include missing unattended children and absentee of teachers. Initially, mass drug administration at school for parasitic infections was thought to improve health and even socioeconomic status of children in the community. However, more recently the socioeconomic impact has been questioned although the reduction of parasitic diseases is still apparent. Moreover, other basic public health measurements such as increased toilet use, assuring safe water access and avoiding the use of human excrement as an agricultural fertilizer, are equally important for control and prevention of parasitic diseases. Further global efforts should be continued to achieve equal health for every child in a sustainable way.
Topics: Africa; Animals; Child; Cross-Sectional Studies; Helminthiasis; Humans; Japan; Parasites; Prevalence; Schools
PubMed: 33174267
DOI: 10.1111/ped.14535 -
Research in Veterinary Science May 2021Parasites, including helminths and protists, are pathogens responsible for waterborne and foodborne illnesses in both developed and developing countries. Their global...
Parasites, including helminths and protists, are pathogens responsible for waterborne and foodborne illnesses in both developed and developing countries. Their global incidence is difficult to estimate, but the World Health Organization (WHO) has indicated the global disease burden of 11 waterborne and foodborne parasitic diseases, is responsible for causing over 407 million illnesses resulting in an estimated of 94 K deaths and 11 million disability-adjusted life years (DALYs). Nevertheless, compared with bacteria and viruses, parasites are often overlooked as etiological agents of foodborne or waterborne disease; this is due to a variety of reasons, including the difficulty of their identification in environmental matrices and because many have a prolonged period between infection and symptoms, making it difficult to implicate infection vehicles. This Special Issue comprises 17 articles that include the more significant waterborne and foodborne parasites of zoonotic importance due to their relevance, with all groups of parasites (protist, cestodes, trematodes, and nematodes) being represented. Each chapter covers relevant aspects regarding -the importance of the parasite in food and water, including an overview of outbreaks where relevant, information on fundamental epidemiological aspects such as transmission, lifecycle and host range, clinical aspects such as pathogenesis, diagnosis and treatment, a summary of prospects for control in water or the food chain, and, finally, providing the authors' opinions regarding future research or studies required to improve control of transmission to people via food or water.
Topics: Animals; Disease Outbreaks; Food Parasitology; Foodborne Diseases; Humans; Incidence; Parasites; Parasitic Diseases, Animal; Veterinarians; Water; Zoonoses
PubMed: 33684793
DOI: 10.1016/j.rvsc.2021.02.020 -
Future Medicinal Chemistry Aug 2019Parasitic infections are responsible for significant morbidity and mortality throughout the world. Management strategies rely primarily on antiparasitic drugs that have... (Review)
Review
Parasitic infections are responsible for significant morbidity and mortality throughout the world. Management strategies rely primarily on antiparasitic drugs that have side effects and risk of drug resistance. Therefore, novel strategies are needed for treatment of parasitic infections. Host-directed therapy (HDT) is a viable alternative, which targets host pathways responsible for parasite invasion/survival/pathogenicity. Recent innovative combinations of genomics, proteomics and computational biology approaches have led to discovery of several host pathways that could be promising targets for HDT for treating parasitic infections. Herein, we review major advances in HDT for parasitic disease with regard to core regulatory pathways and their interactions.
Topics: Anti-Infective Agents; Antibodies, Monoclonal; Cannabinoids; Chagas Disease; Humans; Leishmaniasis; Parasitic Diseases; T-Lymphocytes; Toxoplasmosis; Trypanosoma cruzi
PubMed: 31390889
DOI: 10.4155/fmc-2018-0439 -
Frontiers in Immunology 2022Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of... (Review)
Review
Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of these infections result from a complex interplay between the parasites and the host inflammatory response. Here we review some of the diseases caused by selected parasitic organisms known to infect the nervous system including , , spp., and species. For each parasite, we describe the geographical distribution, prevalence, life cycle, and typical clinical symptoms of infection and pathogenesis. We pay particular attention to how the parasites infect the brain and the interaction between each organism and the host immune system. We describe how an understanding of these processes may guide optimal diagnostic and therapeutic strategies to treat these disorders. Finally, we highlight current gaps in our understanding of disease pathophysiology and call for increased interrogation of these often-neglected disorders of the nervous system.
Topics: Animals; Parasites; Parasitic Diseases; Plasmodium falciparum; Toxoplasma; Trypanosoma brucei brucei
PubMed: 35222377
DOI: 10.3389/fimmu.2022.791488 -
Parasitology Dec 2022Finfish aquaculture in freshwater and marine environments is continuously expanding globally, and the potential for a substantial further increase is well documented.... (Review)
Review
Finfish aquaculture in freshwater and marine environments is continuously expanding globally, and the potential for a substantial further increase is well documented. The industry is supplying fish products for human consumption to the same extent as capture fisheries, and new fish species for domestication are still being selected by the industry. The challenge faced by all aquacultured species, classical and novel, is the range of pathogens associated with each new fish type. A fish host in its natural environment carries a series of more or less specific parasites (specialists and generalists). Some of these show a marked ability to propagate in aquaculture settings. They may then elicit disease when infection intensities in the confined aquaculture environment reach high levels. In addition, the risk of transmission of parasites from aquaculture enterprises to wild fish stocks adds to the parasitic challenge. Control programmes of various kinds are needed and these may include chemotherapeutants and medicines as the farmer's first and convenient choice, but mechanical, biological, immunological and genetic control methods are available solutions. New methods are still to be developed by scrutinizing the life cycle of each particular parasite species and pin-pointing the vulnerable stage to be targeted. As parasites exhibit a huge potential for adaptation to environmental changes, one must realize that only one approach rarely is sufficient. The present work therefore elaborates on and advocates for implementation of integrated control strategies for diseases caused by protozoan and metazoan parasites.
Topics: Animals; Humans; Fish Diseases; Aquaculture; Fisheries; Fishes; Parasites; Parasitic Diseases
PubMed: 35950444
DOI: 10.1017/S0031182022001093 -
Clinical Pharmacokinetics Jul 2020About one-sixth of the world's population is affected by a neglected tropical disease as defined by the World Health Organization and Center for Disease Control.... (Review)
Review
About one-sixth of the world's population is affected by a neglected tropical disease as defined by the World Health Organization and Center for Disease Control. Parasitic diseases comprise most of the neglected tropical disease list and they are causing enormous amounts of disability, morbidity, mortality, and healthcare costs worldwide. The burden of disease of the top five parasitic diseases has been estimated to amount to a total 23 million disability-adjusted life-years. Despite the massive health and economic impact, most drugs currently used for the treatment of parasitic diseases have been developed decades ago and insufficient novel drugs are being developed. The current review provides a compilation of the systemic and target-site pharmacokinetics of established antiparasitic drugs. Knowledge of the pharmacokinetic profile of drugs allows for the examination and possibly optimization of existing dosing schemes. Many symptoms of parasitic diseases are caused by parasites residing in different host tissues. Penetration of the antiparasitic drug into these tissues, the target site of infection, is a prerequisite for a successful treatment of the disease. Therefore, for the examination and improvement of established dosing regimens, not only the plasma but also the tissue pharmacokinetics of the drug have to be considered. For the current paper, almost 7000 scientific articles were identified and screened from which 429 were reviewed in detail and 100 were included in this paper. Systemic pharmacokinetics are available for most antiparasitic drugs but in many cases, not for all the relevant patient populations and only for single- or multiple-dose administration. Systemic pharmacokinetic data in patients with organ impairment and target-site pharmacokinetic data for relevant tissues and body fluids are mostly lacking. To improve the treatment of patients with parasitic diseases, research in these areas is urgently needed.
Topics: Antiparasitic Agents; Humans; Neglected Diseases; Parasitic Diseases; Tropical Medicine
PubMed: 32100246
DOI: 10.1007/s40262-020-00871-5 -
Emerging Infectious Diseases Aug 2021Surveillance for soil-transmitted helminths, strongyloidiasis, cryptosporidiosis, and giardiasis was conducted in Mississippi, USA. PCR performed on 224 fecal samples...
Surveillance for soil-transmitted helminths, strongyloidiasis, cryptosporidiosis, and giardiasis was conducted in Mississippi, USA. PCR performed on 224 fecal samples for all soil-transmitted helminths and on 370 samples for only Necator americanus and Strongyloides stercoralis identified 1 S. stercoralis infection. Seroprevalences were 8.8% for Toxocara, 27.4% for Cryptosporidium, 5.7% for Giardia, and 0.2% for Strongyloides parasites.
Topics: Cryptosporidiosis; Cryptosporidium; Feces; Giardiasis; Humans; Mississippi; Parasitic Diseases
PubMed: 34287125
DOI: 10.3201/eid2708.204318