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The origin of worms, which were occasionally excreted by some individuals, has left humans wondering for centuries. The story of the gradual discovery of the life cycles of the parasitic helminths is a fascinating one, peppered with misconceptions, misguided by dogmas of the church and enlightened by brave men, who did not recant when they were attacked by the opinion leaders of their time. This article will try to pinpoint some of the key discoveries which turned out to be milestones for the elucidation of the secret life of helminths., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Lakatos's philosophy of science has been used for different branches of biology, however this has not been true for helminthology. Therefore, this article examines the possibility of using his methodology of scientific research programmes (SRP) for reconstructing the history of the discipline of helminthology. It is upheld that the first SRP in biology was inaugurated by Aristotle, and its protective belt included a small group of auxiliary hypotheses referring to helminths. This programme continued up until the 17th century, when two rival programmes in helminthology arose: the internalist and the externalist. After the second half of the 19th century the internalist SRP was abandoned, while the externalist considerably broadened its protective belt during the 20th century. The internalist programme was abandoned due to the crucial experiments of Küchenmeister, which permitted the consolidation of the externalist SRP.

Background: Helminths and protozoa infections pose a great burden especially in developing countries, due to morbidity caused by both acute and chronic infection. The aim of our survey was to analyze the intestinal parasitic burden in communities from Mwanza region, Tanzania., Methods: Subjects (n=251) from four villages on the South of Lake Victoria have been analyzed for intestinal parasites with direct smear (DS), formol-ether concentration method (FECM) and the newly developed Mini-FLOTAC technique; urinary schistosomiasis was also assessed in a subsample (n=151); symptoms were registered and correlation between clinic and infections was calculated by chi-squared test and logistical regression., Results: Out of the subjects screened for intestinal and for urinary parasites, 87% (218/251) were found positive for any infection, 69% (174/251) carried a helminthic and 67% (167/251) a protozoan infection, almost half of them had a double or triple infection. The most common helminths were hookworms, followed by Schistosoma mansoni and Schistosoma haematobium. Among protozoa, the most common was Entamoeba coli followed by Entamoeba histolytica/dispar and Giardia intestinalis. Mini-FLOTAC detected a number of helminth infections (61.7%) higher than FECM (38.6%) and DS (17.9%). Some positive associations with abdominal symptoms were found and previous treatment was negatively correlated with infection., Conclusion: Despite the limited size of the examined population the current study indicates a high prevalence of intestinal parasitic infection in Bukumbi area, Tanzania, and Mini-FLOTAC showed to be a promising diagnostic tool for helminth infections. This high parasitic burden calls for starting a regular deworming programme and other preventive interventions in schools and in the community., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Paleoparasitology in the Old World has mainly concerned the study of latrine sediments and coprolites collected from mummified bodies or archaeological strata, mostly preserved by natural conditions. For the first time, different unusual archaeological samples were studied to look for the eggs of helminths parasites (embalming reject jar, canopic package, shroud). Now, samples of organic matter have been successfully processed in order to extract helminths eggs, following the protocol of BOUCHET 2001 (4). Helminth eggs are frequently preserved in the late Quaternary archaeological contexts because of their hard-wearing chitin shell. Six types of eggs were revealed (Schistosoma mansoni, Schistosoma haematobium, Taenia, Enterobius vermicularis, Ascaris lumbricoides and Trichuris trichiura). This study allows to enlarge the Palaeoparasitological research with material never exploited. Moreover, if we take into account identified parasite and geography, it's possible to enlarge the debate to parasite spatio-temporal migration. Considering the particular context of samples preservation, it's interesting to observe an exceptional conservation of parasitological sign related to excellent taphonomic condition (aridity anaeroby, rapid interruption of thanatomorphosis, natural "mummification").

A historical review of the medical helminthology beginning with the Nile religious ideas, the supremacy of the Aristotelian spontaneous generation, the Latin encyclopedism, the medieval transition, the decisive renacentist concept of "pathogenic parasite" until the new discoveries and the therapeutic progress because of the use of the microscope and the development of the experimental method. Finally, the situation in Venezuela, specially about the university teaching, is highlighted.

The results using the Hoyer method for examining eggs of helminths enteroparasites are presented. This method is particularly suited for teaching and on research purposes. Using this technique in fecal sample containing eggs of A. lumbricoides, T. trichiura, Uncinaria sp., Taenia sp., Diphyllobothrium sp., H. nana, H. diminuta and F. hepatica allowed the correct identification of then after 24 hours up to 180 days after the samples were obtained.

Review of the most important contributions of the-25-year-old Department of Medical Parasitology and of the ten-year-old Reference Laboratory for Medical Arachno-Entomology at the Sanitary Inspection and Institute, District of Leipzig, as an example for the performance of hygienic zoology in the German Democratic Republic.

To review the appropriateness of standard reference procedures for diagnostic parasitology, we examined 2,206 stool specimens in our laboratory by direct wet mounting with saline and iodine, by saline and iodine wet mounting from Formalin-ethyl acetate concentrates, and by permanent staining with Wheatley's modified trichrome method (W.B. Wheatley, Am. J. Clin. Pathol. 21: 990-991, 1951). Parasites were detected in 98 stool specimens (4.4%). In all but three specimens, direct wet mounting with saline and iodine contributed little significant information to the result yet consumed substantial technical time. We recommend that with preserved feces a direct examination not be performed but that examination of both a concentrate and a permanent stain be routine.

The school of Professor A. A. Sobolev (1904-1966) which was formed in the city of Gorky represents one of the branches of Academician K. I. Skrjabin's helminthological school. The scientists belonging to this school were the first to begin wide investigations in the ecology of helminths. Evolution of scientific themes of the school allows the ways and regularities of ecological investigations of helminthology in the USSR to be revealed.

Objective. To determine the prevalence of helminth infection in Trichomycterus nigromaculatus captured in environments defined from the physicochemistry of the Gaira River, in Minca, Sierra Nevada de Santa Marta, Colombia. Material and Methods. We collected 476 specimens of T. nigromaculatus covering both climatic periods of the area, which were dissected to analyze the visceral cavity. Isolated parasites were fixed in 10% formalin for subsequent clarification. The specimens were identified by observation of adult stages under a stereoscopic microscope after clarification. Results. Specimens were found exclusively from the genus Spirocamallanus (Nematoda), the species Spirocamallanus sp. parasitic prevalence ranged from 0% in August to 28.57% in April with an abundance of 1.09 worms/host. Environmental parameters such as dissolved oxygen (Mean:5.65 mg. L-1, Max:7.5 mg. L-1, Min:4.41 mg. L-1); pH (Mean:7.2, Max: 9.3, Min: 5.7) and conductivity (Mean:72.82 µs.cm-1, Max: 123.7 µs.cm-1, Min: 40 µs.cm-1) presented statistically significant differences, the environment is eutrophicated. Conclusions. Spirocamallanus sp. were described in the areas of presence of the parasitic association in T. nigromaculatus, which constitutes a new record for the Colombian Caribbean and an extension of the geographic distribution and host range of the nematode. [ABSTRACT FROM AUTHOR]

The white-eared opossum (Didelphis albiventris) is a neotropical marsupial that inhabits various ecoregions and highly modified environments. However, there is limited research on host-parasite interactions and the structure of helminth communities in D. albiventris. Therefore, the aim of this study is to investigate the intestinal helminths of D. albiventris inhabiting a rural area in Buenos Aires, Argentina, and assess the relationship between host age and sex and helminth community structure. Opposums were captured in 2004 and intestines were examined to detect helminths. By analyzing 22 intestines, we identified a total of 8 978 helminths, including Cruzia tentaculata, Turgida turgida, Rhopalias coronatus, Brachylaima sp., individuals of the family Diplostomidae, and a single specimen of a cestode. Among these, C. tentaculata and R. coronatus were the most prevalent species, with C. tentaculata exhibiting the highest levels of abundance, mean intensity, and aggregation index. To assess the influence of host sex and age on parasite abundance and probability of occurrence, we conducted Generalized Linear Models. The results revealed that host juveniles had lower helminth prevalence and abundance compared to other age categories. Host sex was only significant in interaction with host age for parasite abundance in C. tentaculata and R. coronatus. Most captured juveniles relied on maternal feeding, potentially reducing exposure to consuming infected intermediate hosts with indirect life cycles. Understanding the parasite ecology of this opossum species in modified environments provides valuable information about their role at the wildlife-human interface in anthropogenic areas. [ABSTRACT FROM AUTHOR]

Abstract The big-headed Amazon River turtle, Peltocephalus dumerilianus, is endemic to the Orinoco and Amazon River basins. It is a food source for local communities, often unsustainably. Knowledge about P. dumerilianus’ parasitological fauna and host-parasite relationships is limited. Thus, ecological aspects of gastrointestinal parasitism in this species were investigated. Helminths were found in the gastrointestinal tract of 21 turtles, morphologically identified, and infection descriptors calculated. All animals harbored helminths: nematodes Ancyracanthus pinnatifidus, Paratractis hystrix, Atractis trematophila, Klossinemella conciliatus indeterminate three Klossinemella species, and digeneans Nematophila grandis, Helicotrema spirale, and Telorchis hagmanni. The highest parasite load occurred in the large intestine, followed by the small intestine and stomach. Shell length directly correlated with parasite burden of heteroxenic helminths, with males having higher burden than females. This is the first record of A. trematophila, K. conciliatus, and T. hagmanni in P. dumerilianus, and new location record for A. trematophila, P. hystrix, N. grandis, H. spirale, and T. hagmanni. Three potentially new Klossinemella species are presented.

Sphyraena ensis is distributed in the Eastern Pacific from Mexico to Chile, including the Galapagos Islands. Despite the wide distribution of this fish, knowledge of the parasitic fauna of S. ensis is restricted to only three monogenean species. The objective of this study was to record and describe two monogenean species of S. ensis in northern Peru. During a parasitological study from May to October 2019, monogeneans were collected from the gills of 138 specimens of S. ensis from Caleta de Zorritos, Contralmirante Villar Province, Tumbes, on the north coast of Peru. Helminths were stained in carmine acetic acid, dehydrated in ethyl alcohol, diaphanized in clove oil and mounted in Canada balsam. To observe the sclerotized structures, several specimens were placed in Hoyer’s medium. We identified the following monogeneans not previously reported in Peru: Pseudochauhanea mexicana and Scomberocotyle scomberomori. This is the first report of these two monogeneans in Peru, and the first report of P. mexicana in South America. Furthermore, S. ensis is reported as a new host of S. scomberomori.

Parasitic infections can have profound implications on host fitness, yet there is minimal information on parasites of the American horseshoe crab (Limulus polyphemus), a species that has experienced recent population declines. Therefore, we aimed to quantify the prevalence, intensity, and gill surface area coverage of the ectoparasite Bdelloura candida in adult (n = 58), sub-adult (n = 7) and juvenile (n = 32) horseshoe crabs (HSCs) collected from coastal waters of Long Island, NY in 2019 and 2022. Sub samples of horseshoe crab gill tissue (10%) were collected from live specimens and B. candida cocoon intensities from individual lamellae were enumerated microscopically. B. candida was present in all adult and sub-adult crabs (100%), whereas juveniles exhibited 6.2% prevalence. 4.0–94.0% of gill lamellae harbored cocoons, with intensities ranging from 0 to 805 cocoons per sub sample. Cocoon covered between 0.06%–14.51% of the gill sub sample surface area, with higher cocoon intensities observed in the ventral-most gill quartiles relative to the dorsal-most regions. Sex was strongly supported as a primary driver behind B. candida infection intensities with adult females harboring higher intensities. These results provide novel insight into B. candida infection dynamics across HSC demographics, but further research is necessary to quantify the physiological impacts of the infection on L. polyphemus. [ABSTRACT FROM AUTHOR]

Ensuring the veterinary and sanitary welfare of animals is essential. Parasitic diseases are especially dangerous for deer. Helminths cause considerable material damage to deer farms, mainly decreasing the productive, trophy, and marketable qualities of animals. This article studies the distribution and features of preventing helminthiasis of wild ungulates. In ungulate populations settled in new ecological conditions, helminth fauna formation depends on many factors. In particular, this process is influenced by the correct selection of the settlement area, the physiological state of animals, the organization of animal feeding, medical and preventive measures, etc. Among the main measures for preventing helminthiasis in deer in the conditions of their semi-free keeping (farms, aviaries), those that reduce the possibility of infection of animals with parasites common to domestic animals are also vital. Wild animals are much more often infected with helminths of domestic animals, and the most dangerous parasitosis for them are fasciolosis, parafasciolopsosis, cysticercosis, trichostrongylidosis of ruminants. Infection with nematodes Capillaria spp. is characteristic exclusively for red deer, and the intensity of infestation is higher for this species of ruminant ungulates in free-range conditions. According to some researchers, mecystocirosis and strongyloidosis are among the most common helminthiasis in deer, the infection with pathogens of which is 74.5 and 73.3 %, respectively. Parafasciolopsoses (IE – 5.9 %), nematodirus (IE – 5.9 %), and paramphistomatids (IE – 2.8 %) are found somewhat less often. Thus, the study of helminth fauna, the development and implementation of adequate means, and methods of prevention of parasites in wild animals acquire considerable relevance. There are several ways to prevent helminthiasis in hunting and aviary deer farms; when examining the land and choosing an area for aviaries for deer, a helminthological assessment should be taken into account; it is mandatory to examine animals for helminthiasis (parasitocenoses) and carry out deworming of all imported animals; carry out annual disinfestation of feeders, watering holes, places for feeding, protective structures for animals; it is crucial to rationally place biotechnical facilities in areas safe from parasitosis; infected animals with characteristic clinical signs of the disease must be culled. There is quite a lot of information in the available literature regarding the group method of using anthelmintics for deer. [ABSTRACT FROM AUTHOR]

Background: Leafy vegetables could be contaminated with parasitic infective stages, making them possible sources of human parasitic infections. This study aimed to assess parasites contamination level among five different leafy vegetables collected from open marketplaces in Giza, Egypt. Methods: Hundred vegetable samples were collected from dill, parsley, coriander, rocca, and mint (20 of each). Samples were processed using sedimentation and concentration methods and the sediments were examined as wet smears either unstained or stained with Lugol's iodine. Also, modified trichrome and Ziehl-Neelsen stains were used to detect Microsporidia spores and coccidian oocysts. Statistical software SPSS version 20 was used for data analysis. Results: A total of 86% of the examined samples were found contaminated with parasite's eggs, cysts, oocysts, and larvae. Coriander was the most contaminated vegetable with contamination rate of 95% while dill was the least contaminated (80%). Also, protozoan parasites contamination rate (77.1%) was higher than helminths parasites contamination rate (22.9%). Entamoeba histolytica/dispar was the most prevalent parasite (40.6%) followed by Blastocystis hominis (39.5%), Ascaris lumbricoides (18.6%), Cyclospora spp. (15.11%), Giardia lamblia (11.6%), E. coli (9.3%); while Cryptosporidium spp., Iodamoeba bütschlii, Trichuris trichiura, Enterobius vermicularis, Fasciola, and hookworms’ eggs were the least prevalent parasites (1.1%). Conclusion: Leafy vegetables in Giza, Egypt had an extremely high parasite contamination rate. So, consuming such vegetables without proper washing facilitates transmission of parasitic infections which could pose a major health risk to Egyptians. DOI: 10.18502/jfqhc.10.1.11984

[Display omitted] • Well-designed experiments should account for sex of subjects without bias. • Analysis of >3600 parasitological experiments reveals multiple biases and poor reporting. • Inclusion of both host sexes varies with the taxa involved, research area and over time. • The same factors affect whether sex disaggregated data and results are presented. • We offer recommendations for equal inclusion of both sexes in parasitological studies. Experimental approaches are among the most powerful tools available to biologists, yet in many disciplines their results have been questioned due to an underrepresentation of female animal subjects. In parasitology, experiments are crucial to understand host-parasite interactions, parasite development, host immune responses, as well as the efficacy of different control methods. However, distinguishing between species-wide and sex-specific effects requires the balanced inclusion of both male and female hosts in experiments and the reporting of results for each sex separately. Here, using data from over 3600 parasitological experiments on helminth-mammal interactions published in the past four decades, we investigate patterns of male versus female subject use and result reporting practices in experimental parasitology. We uncover multiple effects of the parasite taxon used, the type of host used (rats and mice for which subject selection is fully under researcher control versus farm animals), the research subject area and the year of publication, on whether host sex is even specified, whether one or both host sexes have been used (and if only one then which one), and whether the results are presented separately for each host sex. We discuss possible reasons for biases and unjustifiable selection of host subjects, and for poor experimental design and reporting of results. Finally, we make some simple recommendations for increased rigour in experimental design and to reset experimental approaches as a cornerstone of parasitological research. [ABSTRACT FROM AUTHOR]

Background: Leafy vegetables could be contaminated with parasitic infective stages, making them possible sources of human parasitic infections. This study aimed to assess parasites contamination level among five different leafy vegetables collected from open marketplaces in Giza, Egypt. Methods: Hundred vegetable samples were collected from dill, parsley, coriander, rocca, and mint (20 of each). Samples were processed using sedimentation and concentration methods and the sediments were examined as wet smears either unstained or stained with Lugol's iodine. Also, modified trichrome and Ziehl-Neelsen stains were used to detect Microsporidia spores and coccidian oocysts. Statistical software SPSS version 20 was used for data analysis. Results: A total of 86% of the examined samples were found contaminated with parasite's eggs, cysts, oocysts, and larvae. Coriander was the most contaminated vegetable with contamination rate of 95% while dill was the least contaminated (80%). Also, protozoan parasites contamination rate (77.1%) was higher than helminths parasites contamination rate (22.9%). Entamoeba histolytica/dispar was the most prevalent parasite (40.6%) followed by Blastocystis hominis (39.5%), Ascaris lumbricoides (18.6%), Cyclospora spp. (15.11%), Giardia lamblia (11.6%), E. coli (9.3%); while Cryptosporidium spp., Iodamoeba bütschlii, Trichuris trichiura, Enterobius vermicularis, Fasciola, and hookworms' eggs were the least prevalent parasites (1.1%). Conclusion: Leafy vegetables in Giza, Egypt had an extremely high parasite contamination rate. So, consuming such vegetables without proper washing facilitates transmission of parasitic infections which could pose a major health risk to Egyptians. [ABSTRACT FROM AUTHOR]

Most types of helminths are widespread in many countries and severely threaten human health. One of the most dangerous zooanthropohelminthiases is toxocarosis. The causative agent of toxocarosis – the nematode Toxocara canis in the imaginal stage parasitizes in the small intestine of carnivores and the larval stage (Visceralis larva migrans) – in various organs and tissues of animals and humans. Toxocarosis has both veterinary and social significance. Toxocara canis larvae can migrate in the human body and cause various pathologies: hepatitis, encephalitis, chorioretinitis. The purpose of the research was to analyze data from the reporting documentation of the Poltava Veterinary Center regarding the prevalence of toxocarosis among the domestic dog population. According to the results of the analysis of the statistical data of the reporting documentation of the veterinary center of the Shevchenkivskyi district of the city of Poltava for 2019–2022, it was established that the average infestation of dogs by the causative agent of toxocarosis in the territory of the city of Poltava is 22.89 %, with a range from 17.51 to 28.02 %. The share of toxocarosis in the total parasitic pathology diagnosed in dogs was 27 %. The mestizos were the most affected by the causative agent of toxocarosis, where the extent of invasion was 29.26 %. A lower rate of toxocares was found in dogs of decorative (24.05 %), service (21.24 %), and hunting (18.56 %) breeds. In particular, the highest values of the extent of infestation were found in Yorkshire terriers (39.71 %). Less often, toxocarosis was diagnosed in toy terriers (extent of infestation – 19.12 %), English cocker spaniels (19.83 %), dachshunds (18.03 %), pugs (16.37 %), Jack Russell terriers (15.82 %) and pickiness (12.6 %). Seasonal dynamics of toxocarosis in dogs are characterized by the peak of invasion in the spring and autumn periods, where the infection rates of animals were at 35.0 and 30.0 %, respectively. The extent of toxocarosis infestation declined in winter – by 12.0 %. The obtained data indicate the relevance of the problem of toxocarosis as a zooanthroponous invasion in connection with the significant damage to domestic dogs by toxocares in the city of Poltava. [ABSTRACT FROM AUTHOR]

One of the conditions for successfully managing rabbit breeding is ensuring the epizootological well-being of farms concerning invasive animal diseases. Helminthiases, protozooses, and acaroses cause significant economic damage to the industry due to a decrease in the biological value of rabbit meat and skins, a delay in growth, development, and a decrease in the growth of young animals, as well as their death. Carrying out epizootic monitoring and assessment of the epizootic situation in different regions of Ukraine is one of the main preventive measures, which, based on the results of the study of the epizootic state, analysis of veterinary reports, and the results of laboratory tests, will allow effective treatment and prevention of invasive diseases in rabbit farms. The purpose of the work was to conduct monitoring studies of the epizootic situation regarding rabbit parasitoses in the territory of some areas of Ukraine. It was established that the total incidence of domestic rabbits by parasitoses was 36.27 %. The weight of infestations caused by the simplest organisms was the highest, reaching 81.96 %. The specific weight of infestations caused by acariform mites, nematodes, and cestodes was insignificant and amounted to 9.88 %, 7.3 %, and 0.86 %, respectively. Among the protozooses – eimeriosis, nematodoses – pasalurosis, cestodoses – cysticercosis, acaroses –psoroptosis were found in rabbits. High indicators of the extensiveness of animal invasion were established for eimeriosis (50.23 %). Smaller values of infestation of rabbits were found for psoroptosis (18.0 %) and pasalurosis (16.87 %). For pysiform cysticercosis, the extent of invasion was insignificant – 5.97 %. Indicators of the extensiveness of invasions in different regions of Ukraine ranged from 15.28 to 100.0 % for eimeriosis, from 4.35 to 100.0 % for pasalurosis, from 50.0 to 100.0 % for cysticercosis, and from psoroptosis 11.54 to 100.0 %. The obtained results of monitoring studies on the epizootic status of invasive rabbit diseases on the territory of Ukraine indicate the relevance and perspective of further studying the distribution of parasite fauna in the population of domestic rabbits, taking into account the climatic conditions of different regions, the way rabbits are kept, their age and season. [ABSTRACT FROM AUTHOR]