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Enfermedades Infecciosas Y... 2016Millions of people in in rural areas and deprived tropical and subtropical regions are infected by soil-transmitted helminths: Ascaris lumbricoides, Trichuris trichiura,...
Millions of people in in rural areas and deprived tropical and subtropical regions are infected by soil-transmitted helminths: Ascaris lumbricoides, Trichuris trichiura, hookworms (Ancylostoma duodenale and Necator americanus), and Strongyloides stercoralis. Large migratory flows have made their worldwide distribution easier. Besides being debilitating and producing a significant mortality, they cause high morbidity, leading to physical and intellectual impairment in millions of children who live in poverty. Along with the use of benzimidazoles (albendazole and mebendazole), large-scale international campaigns for treatment and prevention have decreased the number of affected individuals. However, re-infestations and benzimidazole-resistance are frequent, so there needs to be awareness about the importance and consequences of these neglected parasites.
Topics: Ancylostoma; Ancylostomatoidea; Animals; Ascaris lumbricoides; Helminthiasis; Humans; Necator americanus; Rural Population; Soil; Trichuris; Tropical Climate; Vulnerable Populations
PubMed: 26980233
DOI: 10.1016/j.eimc.2016.02.002 -
Trends in Parasitology Sep 2021
Review
Topics: Ancylostoma; Ancylostomiasis; Animals; Humans; Life Cycle Stages
PubMed: 34049804
DOI: 10.1016/j.pt.2021.04.013 -
Nature Reviews. Disease Primers Dec 2016Hookworms are soil-transmitted nematode parasites that can reside for many years in the small intestine of their human hosts; Necator americanus is the predominant... (Review)
Review
Hookworms are soil-transmitted nematode parasites that can reside for many years in the small intestine of their human hosts; Necator americanus is the predominant infecting species. Adult worms feed on the blood of a host and can cause iron deficiency anaemia, especially in high-risk populations (children and women of childbearing age). Almost 500 million people in developing tropical countries are infected, and simulation models estimate that hookworm infection is responsible for >4 million disability-adjusted life years lost annually. Humans mount an immune response to hookworms, but it is mostly unsuccessful at removing adult worms from the bowel. Accordingly, the host switches to an immune-tolerant state that enables hookworms to reside in the gut for many years. Although anthelmintic drugs are available and widely used, their efficacy varies and the drugs do not prevent reinfection. Thus, other control strategies aimed at improving water quality, sanitation and hygiene are needed. In addition, efforts are underway to develop a human hookworm vaccine through public-private partnerships. However, hookworms could also be a resource; as hookworms have the capability to regulate the host's inflammation, researchers are experimentally infecting patients to treat some inflammatory diseases as an approach to discover new anti-inflammatory molecules. This area of endeavour might well yield new biotherapeutics for autoimmune and allergic diseases.
Topics: Albendazole; Ancylostomatoidea; Anemia; Animals; Anthelmintics; Factor VIIa; Factor XIa; Factor Xa; Feces; Hemorrhage; Hookworm Infections; Humans; Intestine, Small; Larva Migrans; Mebendazole; Necator americanus; Prevalence; Risk Factors; Soil
PubMed: 27929101
DOI: 10.1038/nrdp.2016.88 -
Parasitology International Jun 2024Follicular larva migrans (FLM) is a rare and atypical clinical presentation of hookworm-related cutaneous larva migrans (HrCLM). FLM is characterized clinically by... (Review)
Review
Follicular larva migrans (FLM) is a rare and atypical clinical presentation of hookworm-related cutaneous larva migrans (HrCLM). FLM is characterized clinically by follicular, round, small, erythematous papules that are sometimes topped by vesicles or pustules. These lesions are usually located on the abdomen, back, buttocks and thighs and are accompanied by more or less severe pruritus. Some typical and/or short and fragmented tracks may also be visible. FLM is more resistant to anti-helminthic drugs than classical HrCLM: this is likely due to the deep location of larvae in hair follicles. We present two cases of FLM and a review of the literature.
Topics: Animals; Larva Migrans; Anthelmintics; Ancylostomatoidea; Larva
PubMed: 38428565
DOI: 10.1016/j.parint.2024.102872 -
JAMA Neurology Sep 2020
Topics: Ancylostomatoidea; Animals; Humans; Multiple Sclerosis
PubMed: 32539129
DOI: 10.1001/jamaneurol.2020.0519 -
Acta Tropica Mar 2023It has been tested and proven that vaccination is still the best strategy to combat infectious diseases. However, to date, there are still no vaccines against human... (Review)
Review
It has been tested and proven that vaccination is still the best strategy to combat infectious diseases. However, to date, there are still no vaccines against human soil-transmitted helminthic diseases, despite their high prevalence globally, particularly in developing countries and rural areas with tropical climates and poor sanitation. The development of vaccines against helminths is riddled with obstacles. Helminths have a complex life cycle, multiple stages within the same host with stage-specific antigen expression, and the ability to regulate host immune reactions to evade the immune response. These elements contribute to the main challenge of helminthic vaccines: the identification of effective vaccine candidates. Therefore, this article reviews the current progress and potential future direction of soil-transmitted helminthic vaccines, particularly against Trichuris trichiura, Ascaris lumbricoides, Strongyloides stercoralis, Necator americanus and Ancylostoma duodenale. The study design employed was a systematic review, using qualitative meta-summary synthesis. Preclinical studies and clinical trials on the development of protein subunit vaccines against the five soil-transmitted helminths were searched on PubMed and Scopus. Effectiveness was indicated by a reduction in worm burden or larval output, an increase in specific IgG levels, or an increase in cytokine production. Our findings show that only the hookworm vaccine against N. americanus is in the clinical trial phase, while the rest is still in exploratory research and pre-clinical development phase.
Topics: Animals; Humans; Soil; Hookworm Infections; Ascaris lumbricoides; Ancylostomatoidea; Necator americanus; Vaccines; Helminthiasis; Feces
PubMed: 36586174
DOI: 10.1016/j.actatropica.2022.106796 -
Parasites & Vectors Mar 2020Hookworm infection is a major public health problem that threatens about 500 million people throughout tropical areas of the world. Adult hookworms survive for many... (Review)
Review
Hookworm infection is a major public health problem that threatens about 500 million people throughout tropical areas of the world. Adult hookworms survive for many years in the host intestine, where they suck blood, causing iron deficiency anemia and malnutrition. Numerous molecules, named excretory/secretory (ES) products, are secreted by hookworm adults and/or larvae to aid in parasite survival and pathobiology. Although the molecular cloning and characterization of hookworm ES products began 25 years ago, the biological role and molecular nature of many of them are still unclear. Hookworm ES products, with distinct structures and functions, have been linked to many essential events in the disease pathogenesis. These events include host invasion and tissue migration, parasite nourishment and reproduction, and immune modulation. Several of these products represent promising vaccine targets for controlling hookworm disease and therapeutic targets for many inflammatory diseases. This review aims to summarize our present knowledge about hookworm ES products, including their role in parasite biology, host-parasite interactions, and as vaccine and pharmaceutical targets and to identify research gaps and future research directions in this field.
Topics: Ancylostoma; Ancylostomatoidea; Animals; Antioxidants; Body Fluids; Cloning, Molecular; Female; Helminth Proteins; Hookworm Infections; Host-Parasite Interactions; Humans; Immunologic Factors; Male; Peptide Hydrolases; Protease Inhibitors; Vaccines
PubMed: 32171305
DOI: 10.1186/s13071-020-04010-8 -
Trends in Parasitology Jun 2024Hookworms are parasites, closely related to the model nematode Caenorhabditis elegans, that are a major economic and health burden worldwide. Primarily three hookworm... (Review)
Review
Hookworms are parasites, closely related to the model nematode Caenorhabditis elegans, that are a major economic and health burden worldwide. Primarily three hookworm species (Necator americanus, Ancylostoma duodenale, and Ancylostoma ceylanicum) infect humans. Another 100 hookworm species from 19 genera infect primates, ruminants, and carnivores. Genetic data exist for only seven of these species. Genome sequences are available from only four of these species in two genera, leaving 96 others (particularly those parasitizing wildlife) without any genomic data. The most recent hookworm genomes were published 5 years ago, leaving the field in a dusk. However, assembling genomes from single hookworms may bring a new dawn. Here we summarize advances, challenges, and opportunities for studying these neglected but important parasitic nematodes.
Topics: Animals; Genomics; Genome, Helminth; Hookworm Infections; Ancylostomatoidea; Humans
PubMed: 38677925
DOI: 10.1016/j.pt.2024.04.003 -
BMJ (Clinical Research Ed.) Oct 2017
Topics: Alabama; Ancylostomatoidea; Animals; Disease Outbreaks; Dogs; Hookworm Infections; Humans; Neglected Diseases
PubMed: 29066626
DOI: 10.1136/bmj.j4813 -
Parasite Immunology Feb 2018Hookworm is a major public health concern, yet still relatively little is known about the immunological responses involved in human infection. Animal studies are mainly... (Review)
Review
Hookworm is a major public health concern, yet still relatively little is known about the immunological responses involved in human infection. Animal studies are mainly confined to using the natural rodent helminth Nippostrongylus brasiliensis as this has been proposed as the most accurate model of hookworm infection in the mouse, with both its life cycle and the immune responses it invokes having been extremely well characterized. In this review, we examine the roles that type 2 innate lymphoid cells (ILC2s) play in immunity and host tolerance to hookworm infection, particularly N. brasiliensis. This includes their role in the initiation and regulation of immune responses, as well as in the resolution and limitation of tissue damage required after an infection with a large organism, such as a helminth.
Topics: Ancylostomatoidea; Animals; Cytokines; Disease Models, Animal; Female; Hookworm Infections; Humans; Immunity, Innate; Male; Mice; Neglected Diseases; Nippostrongylus; Th2 Cells
PubMed: 28369954
DOI: 10.1111/pim.12429