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International Journal For Parasitology.... Apr 2024The genus contains numerous species of subcutaneous parasites of mammals and reptiles. In North America, there are at least three mammal-infecting species of . Reports...
The genus contains numerous species of subcutaneous parasites of mammals and reptiles. In North America, there are at least three mammal-infecting species of . Reports of infections have been reported from river otters () since the early 1900s; however, little is known about the species infecting otters or their ecology. Most reports of do not have a definitive species identified because females, the most common sex found due to their larger size and location in the extremities of the host, lack distinguishing morphological characteristics, and few studies have used molecular methods to confirm identifications. Thus, outside of Ontario, Canada, where both and have been confirmed in otters, the species of in river otters is unknown. In the current study, molecular characterization of nematodes from river otters revealed a high diversity of species. In addition to confirming infections, two new clades were detected. One clade was a novel species in any host and the other was a clade previously detected in Virginia opossums () from the USA and a domestic dog from Spain. No infections with were detected and neither new lineage was genetically similar to , which was recently described from a neotropical otter () from Argentina. These data also indicate that spp. infections in otters are widespread throughout Eastern North America. Currently the life cycles for most of the spp. infecting otters are unknown. Studies on the diversity, life cycle, and natural history of Dracunculidae parasites in wildlife are important because the related parasite, (human Guinea worm) is the subject of an international eradication campaign and there are increasing reports of these parasites in new geographic locations and new hosts, including new species in humans and domestic dogs.
PubMed: 38516639
DOI: 10.1016/j.ijppaw.2024.100922 -
Le Infezioni in Medicina 2023Dracunculiasis (Guinea Worm Disease) is a chronic disease that is primarily found in the arid and poor areas of our planet where water supply systems consist of open... (Review)
Review
Dracunculiasis (Guinea Worm Disease) is a chronic disease that is primarily found in the arid and poor areas of our planet where water supply systems consist of open wells. This parasitic disease is transmitted to humans not only through the consumption of water contaminated with crustaceans harbouring larvae of , but also through the ingestion of paratenic (frogs) or transport hosts (fish). The natural progression of the disease is caused by adult worms invading connective tissues, leading to blistering and ulceration of the extremities, approximately one year after infection. In 1986, the Guinea Worm Eradication Program (GWEP) was launched and since then, the incidence of the disease has been reduced by over 99%. Indeed, the most recent global report from 2022 shows only 13 cases of human dracunculiasis worldwide, the lowest annual incidence ever reported. The new found knowledge of potential animal reservoirs and the recent discovery of possible edible paratenic hosts could pose challenges to the future eradication of this debilitating disease. Therefore, attempts to eradicate this parasitosis should not be postponed. Intensive research is needed in this neglected area of medicine, now that the goal is within reach.
PubMed: 38075414
DOI: 10.53854/liim-3104-9 -
International Journal For Parasitology.... Dec 2023A new species of is described in wild neotropical otters, , occurring in Corrientes, Argentina, based on morphological and molecular characteristics. Worms were located...
A new species of is described in wild neotropical otters, , occurring in Corrientes, Argentina, based on morphological and molecular characteristics. Worms were located in the subcutaneous tissue from two of five investigated otters. n. sp. is differentiated from the 14 species of described from mammals and reptiles by the prominent dorsal and ventral papillae on the head; deirids posterior to nerve ring; male with long needlelike spicules and presence of gubernaculum; and long first stage larva. Phylogenetic analysis using the 18S rRNA positioned n. sp. in an anterior position to the rest of sequences available and COI positioned it in a separated clade sister to sequences. This is the first report on the presence of this nematode in in Argentina.
PubMed: 38045874
DOI: 10.1016/j.ijppaw.2023.11.002 -
MMWR. Morbidity and Mortality Weekly... Nov 2023The effort to eradicate Dracunculus medinensis, the etiologic agent of dracunculiasis, or Guinea worm disease, commenced at CDC in 1980. In 1986, with an estimated 3.5...
The effort to eradicate Dracunculus medinensis, the etiologic agent of dracunculiasis, or Guinea worm disease, commenced at CDC in 1980. In 1986, with an estimated 3.5 million cases worldwide in 20 African and Asian countries, the World Health Assembly called for dracunculiasis elimination. The Guinea Worm Eradication Program (GWEP) was established to help countries with endemic dracunculiasis reach this goal. GWEP is led by The Carter Center and supported by partners that include the World Health Organization, UNICEF, and CDC. In 2012, D. medinensis infections were unexpectedly confirmed in Chadian dogs, and since then, infections in dogs, cats, and baboons have posed a new challenge for GWEP, as have ongoing civil unrest and insecurity in some areas. By 2022, dracunculiasis was endemic in five countries (Angola, Chad, Ethiopia, Mali, and South Sudan), with only 13 human cases identified, the lowest yearly total ever reported. Animal infections, however, were not declining at the same rate: 686 animal infections were reported in 2022, including 606 (88%) in dogs in Chad. Despite these unanticipated challenges as well as the COVID-19 pandemic, countries appear close to reaching the eradication goal. GWEP will continue working with country programs to address animal infections, civil unrest, and insecurity, that challenge the eradication of Guinea worm.
Topics: Humans; Animals; Dogs; Disease Eradication; Dracunculiasis; Pandemics; Global Health; World Health Organization
PubMed: 37943706
DOI: 10.15585/mmwr.mm7245a4 -
International Journal of Molecular... Sep 2023Among the plants that exhibit significant or established pharmacological activity, the genus L. deserves special attention. This genus comprises over 500 species...
Among the plants that exhibit significant or established pharmacological activity, the genus L. deserves special attention. This genus comprises over 500 species belonging to the largest family. Our study aimed at providing a comprehensive evaluation of the phytochemical composition of the ethanol extracts of five different L. species (collected from the southwest of the Russian Federation) and their antimicrobial and nematocide activity as follows: cv. Novichok., cv. Smaragd, cv. Citral, cv. Euxin, and cv. Tavrida. The study of the ethanol extracts of the five different L. species using the methods of gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-MS/MS) allowed establishing their phytochemical profile. The obtained data on the of five different L. species ethanol extracts' phytochemical composition were used to predict the antibacterial and antifungal activity against phytopathogenic microorganisms and nematocidal activity against the free-living soil nematode . The major compounds found in the composition of the L. ethanol extracts were monoterpenes, sesquiterpenes, flavonoids, flavonoid glycosides, coumarins, and phenolic acids. The antibacterial and antifungal activity of the extracts began to manifest at a concentration of 150 µg/mL. The cv. Smaragd extract had a selective effect against Gram-positive and bacteria, whereas the cv. Tavrida extract had a selective effect against Gram-negative and bacteria and , and fungi. The cv. Novichok, cv. Smaragd, and cv. Citral extracts in the concentration range of 31.3-1000 µg/mL caused the death of nematodes. It was established that cv. Novichok affects the UNC-63 protein, the molecular target of which is the nicotine receptor of the N-subtype.
Topics: Animals; Ethanol; Antifungal Agents; Artemisia; Tandem Mass Spectrometry; Anti-Infective Agents; Anti-Bacterial Agents; Antinematodal Agents; Araceae; Caenorhabditis elegans; Flavonoids; Plant Extracts
PubMed: 37762675
DOI: 10.3390/ijms241814372 -
Medical History Apr 2023Guinea worm disease (dracunculiasis) is a debilitating waterborne disease. Once widespread, it is now on the brink of eradication. However, the Guinea Worm Eradication...
Guinea worm disease (dracunculiasis) is a debilitating waterborne disease. Once widespread, it is now on the brink of eradication. However, the Guinea Worm Eradication Programme (GWEP), like guinea worm itself, has been under-studied by historians. The GWEP demonstrates an unusual model of eradication, one focused on primary healthcare (PHC), community participation, health education and behavioural change (safe drinking). The PHC movement collided with a waterborne disease, which required rapid but straightforward treatment to prevent transmission, creating a historical space for the emergence of village-based volunteer health workers, as local actors realigned global health policy on a local level. These Village Volunteers placed eradication in the hands of residents of endemic areas, epitomising the participation-focused nature of the GWEP. This participatory mode of eradication highlights the agency of those in endemic areas, who, through volunteering, safe drinking and community self-help, have been the driving force behind dracunculiasis eradication. In the twenty-first century, guinea worm has become firstly a problem of human mobility, as global health has struggled to contain cases in refugees and nomads, and latterly a zoonotic disease, as guinea worm has shifted hosts to become primarily a parasite of dogs. This demonstrates both the potential of One Health approaches and the need for One Health to adopt from PHC and the GWEP a focus on the health of humans and animals in isolated and impoverished areas. Guinea worm demonstrates how the biological and the historical interact, with the GWEP and guinea worm shaping each other over the course of the eradication programme.
Topics: Humans; Animals; Dogs; Dracunculus Nematode; Dracunculiasis; Waterborne Diseases; Health Education; Health Policy; Disease Eradication
PubMed: 37525460
DOI: 10.1017/mdh.2023.18 -
Protein Science : a Publication of the... Sep 2023Nicotinic acetylcholine receptors (N-AChRs) mediate fast synaptic signaling and are members of the pentameric ligand-gated ion channel (pLGIC) family. They rely on a...
Nicotinic acetylcholine receptors (N-AChRs) mediate fast synaptic signaling and are members of the pentameric ligand-gated ion channel (pLGIC) family. They rely on a network of accessory proteins in vivo for correct formation and transport to the cell surface. Resistance to cholinesterase 3 (RIC-3) is an endoplasmic reticulum protein that physically interacts with nascent pLGIC subunits and promotes their oligomerization. It is not known why some N-AChRs require RIC-3 in heterologous expression systems, whereas others do not. Previously we reported that the ACR-16 N-AChR from the parasitic nematode Dracunculus medinensis does not require RIC-3 in Xenopus laevis oocytes. This is unusual because all other nematode ACR-16, like the closely related Ascaris suum ACR-16, require RIC-3. Their high sequence similarity limits the number of amino acids that may be responsible, and the goal of this study was to identify them. A series of chimeras and point mutations between A. suum and D. medinensis ACR-16, followed by functional characterization with electrophysiology, identified two residues that account for a majority of the receptor requirement for RIC-3. ACR-16 with R/K159 in the cys-loop and I504 in the C-terminal tail did not require RIC-3 for functional expression. Mutating either of these to R/K159E or I504T, residues found in other nematode ACR-16, conferred a RIC-3 requirement. Our results agree with previous studies showing that these regions interact and are involved in receptor synthesis. Although it is currently unclear what precise mechanism they regulate, these residues may be critical during specific subunit folding and/or assembly cascades that RIC-3 may promote.
Topics: Receptors, Nicotinic; Cholinesterases; Cell Membrane; Endoplasmic Reticulum
PubMed: 37417463
DOI: 10.1002/pro.4718 -
Le Infezioni in Medicina 2023Dracunculiasis (Guinea Worm Disease) is a terrible disease limited, even historically, to the arid and poor areas of our planet and which in the West has always been...
Dracunculiasis (Guinea Worm Disease) is a terrible disease limited, even historically, to the arid and poor areas of our planet and which in the West has always been seen as an exotic disease and therefore has never taken root in the collective imagination. This parasitosis is transmitted to humans by drinking water contaminated with crustacean harboring larvae of , a nematode. The natural history of the disease is caused by adult worms invading connective tissues and causing blistering, ulceration and edema. Well known in Ancient Egypt where the disease was endemic in its southern area, was known in Europe mainly from the reports of medical writers starting from the Roman imperial period but without direct knowledge. In Middle age the descriptions of this disease that physicians and surgeons could read on medical books, at the end, were attributed to veterinary parasitic disease. In Modern age only during the colonialist era dracunculiasis was perceived as a problem, however sporadic. In 1986 Guinea Worm Eradication Program (GWEP) was launch without success. Thus, the disappearance of this parasitosis should still be postponed but not abandoned.
PubMed: 37283632
DOI: 10.53854/liim-3102-15 -
MMWR. Morbidity and Mortality Weekly... Nov 2022Dracunculiasis (Guinea worm disease), caused by the parasite Dracunculus medinensis, is acquired by drinking water containing small crustacean copepods (water fleas)...
Dracunculiasis (Guinea worm disease), caused by the parasite Dracunculus medinensis, is acquired by drinking water containing small crustacean copepods (water fleas) infected with D. medinensis larvae. Recent evidence suggests that the parasite also appears to be transmitted by eating fish or other aquatic animals. About 1 year after infection, the worm typically emerges through the skin on a lower limb of the host, causing pain and disability (1). No vaccine or medicine is available to prevent or treat dracunculiasis. Eradication relies on case containment* to prevent water contamination and other interventions to prevent infection, including health education, water filtration, treatment of unsafe water with temephos (an organophosphate larvicide), and provision of safe drinking water (1,2). CDC began worldwide eradication efforts in October 1980, and in 1984 was designated by the World Health Organization (WHO) as the technical monitor of the Dracunculiasis Eradication Program (1). In 1986, with an estimated 3.5 million cases occurring annually in 20 African and Asian countries (3), the World Health Assembly called for dracunculiasis elimination. The Guinea Worm Eradication Program (GWEP), led by The Carter Center and supported by partners that include WHO, UNICEF, and CDC, began assisting ministries of health in countries with endemic disease. In 2021, a total of 15 human cases were identified and three were identified during January-June 2022. As of November 2022, dracunculiasis remained endemic in five countries (Angola, Chad, Ethiopia, Mali, and South Sudan); cases reported in Cameroon were likely imported from Chad. Eradication efforts in these countries are challenged by infection in animals, the COVID-19 pandemic, civil unrest, and insecurity. Animal infections, mostly in domestic dogs, some domestic cats, and in Ethiopia, a few baboons, have now surpassed human cases, with 863 reported animal infections in 2021 and 296 during January-June 2022. During the COVID-19 pandemic all national GWEPs remained fully operational, implementing precautions to ensure safety of program staff members and community members. In addition, the progress toward eradication and effectiveness of interventions were reviewed at the 2021 and 2022 annual meetings of GWEP program managers, and the 2021 meeting of WHO's International Commission for the Certification of Dracunculiasis Eradication. With only 15 human cases identified in 2021 and three during January-June 2022, program efforts appear to be closer to reaching the goal of eradication. However, dog infections and impeded access because of civil unrest and insecurity in Mali and South Sudan continue to be the greatest challenges for the program. This report describes progress during January 2021-June 2022 and updates previous reports (2,4).
Topics: Humans; Animals; Cats; Dogs; Dracunculiasis; Drinking Water; COVID-19; Pandemics; Disease Eradication
PubMed: 36417302
DOI: 10.15585/mmwr.mm7147a2