Helminth-derived proteins as immune system regulators: a systematic review of their promise in alleviating colitis

Helminth-derived proteins have immunomodulatory properties, influencing the host's immune response as an adaptive strategy for helminth survival. Helminth-derived proteins modulate the immune response by inducing anti-inflammatory cytokines, promoting regulatory T-cell development, and ultimately favouring a Th2-biased immune response. This systematic review focused on helminth-derived proteins and explored their impact on reducing inflammatory responses in mouse models of colitis. A systematic search across Medline, EMBASE, Web of Science, and Cochrane Library identified fourteen relevant studies. These studies reported immunomodulatory changes, including increased production of anti-inflammatory cells and cytokines. In mouse models of colitis treated with on helminth-derived proteins, significant improvements in pathological parameters such as body weight, colon length, and microscopic inflammatory scores were observed compared to control groups. Moreover, helminth-derived proteins can enhance the function of Tregs and alleviate the severity of inflammatory conditions. The findings underscore the pivotal role of helminth-derived proteins in immunomodulation, specifically in the axis of cytokine secretion and immune cell polarization. The findings offer new opportunities for treating chronic inflammatory conditions such Crohn's disease.

Molecular Regulation of NLRP3 Inflammasome Activation During Parasitic Infection

Parasitic diseases are a serious global health concern, causing many common and severe infections, including Chagas disease, leishmaniasis,and schistosomiasis. The NLRP3 inflammasome belongs to the NLR (nucleotide-binding domain leucine-rich-repeat-containing proteins) family, which are cytosolic proteins playing key roles in the detection of pathogens. NLRP3 inflammasomes are activated in immune responses to Plasmodium,Leishmania, Toxoplasma gondii, Entamoeba histolytica,Trypanosoma cruzi and other parasites. The role of NLRP3 is not fully understood, but it is a crucial component of the innate immune response to parasitic infections and its functions as a sensor triggering the inflammatory response to the invasive parasites. However, while this response can limit the parasites' growth, it can also result in potentially catastrophic host pathology. This makes it essential to understand how NLRP3 interacts with parasites to initiate the inflammatory response. Plasmodium hemozoin, Leishmania glycoconjugate lipophosphoglycan (LPG) and E. histolytica Gal/GalNAc lectin can stimulate NLRP3 activation, while the dense granule protein 9 (GRA9) of T. gondii has been shown to suppress it. Several other parasitic products also have diverse effects on NLRP3 activation. Understanding the mechanism of NLRP3 interaction with these products will help to develop advanced therapeutic approaches to treat parasitic diseases. This review summarizes current knowledge of the NLRP3 inflammasome's action on the immune response to parasitic infections and aims to determine the mechanisms through which parasitic molecules either activate or inhibit its action.

Searching for common patterns in parasite ecology: species and host contributions to beta-diversity in helminths of South African ungulates and fleas of South American rodents

We searched for common patterns in parasite ecology by investigating species and host contributions to the beta-diversity of infracommunities (=assemblages of parasites harboured by a host individual) in helminths of three species of South African ungulates and fleas of 11 species of South American rodents, assuming that a comparison of patterns in distinctly different parasites and hosts would allow us to judge the generality or, at least, commonness of these patterns. We used data on species' composition and numbers of parasites and asked whether (i) parasite species' attributes (life cycle, transmission mode, and host specificity in helminths; possession of sclerotized combs, microhabitat preference, and host specificity in fleas) or their population structure (mean abundance and/or prevalence) and (ii) host characteristics (sex and age) affect parasite and host species' contributions to parasite beta-diversity (SCBD and HCBD, respectively). We found that parasite species' morphological and ecological attributes were mostly not associated with their SCBD. In contrast, parasite SCBD, in both ungulates and rodents, significantly increased with either parasite mean abundance or prevalence or both. The effect of host characteristics on HCBD was detected in a few hosts only. In general, parasite infracommunities' beta-diversity appeared to be driven by variation in parasite species rather than the uniqueness of the assemblages harboured by individual hosts. We conclude that some ecological patterns (such as the relationships between SCBD and parasite abundance/prevalence) appear to be common and do not differ between different host-parasite associations in different geographic regions, whereas other patterns (the relationships between SCBD and parasite species' attributes) are contingent and depend on parasite and host identities.

Melatonin: A look at protozoal and helminths

Melatonin is a pleiotropic neurohormone found in different animal, plant, and microorganism species. It is a product resulting from tryptophan metabolism in the pineal gland and is widely known for its ability to synchronize the circadian rhythm to antitumor functions in different types of cancers. The molecular mechanisms responsible for its immunomodulatory, antioxidant and cytoprotective effects involve binding to high-affinity G protein-coupled receptors and interactions with intracellular targets that modulate signal transduction pathways. In vitro and in vivo studies have reported the therapeutic potential of melatonin in different infectious and parasitic diseases. In this review, the protective and pathophysiological roles of melatonin in fighting protozoan and helminth infections and the possible mechanisms involved against these stressors will be discussed.

Development of adult Dirofilaria immitis worms in the Rag2/Il-2rγ-/- mouse model

Dirofilaria immitis is the causative agent for one of the major parasitic infections in dogs. It is currently not possible to reliably diagnose the infection before the development of fertile adult female worms and the presence of microfilariae which takes six to 7 months. However, at this point adult worms already reside in the pulmonary arteries and can cause significant damage. Novel in vivo models may facilitate the development of new diagnostic tools and improve treatment options for both the early and late stages of D. immitis infections. In this paper, we aimed to increase the capabilities of recently published mouse models in which severely immune-deficient mice were shown to be susceptible to D. immitis. Our data shows that D. immitis may grow into fully developed mature male and female worms in C57BL/6 Rag2/Il-2rγ-/- mice with comparable growth rates to the natural canine host. The adult worms of D. immitis were shown to migrate into body cavities as well as the heart in this model. However, the presence of adult worms inside the heart of infected mice led to the development of caval syndrome in 36% of infected mice after five to 6 months. Overall, the current study complements recently published efforts to establish a D. immitis mouse model by extending the development of D. immitis into mature adult stages and will facilitate further preclinical research.

Evaluation of reference genes for gene expression analysis by real-time quantitative PCR (qPCR) in different tissues from mice infected by Ascaris suum

Human ascariasis is the most prevalent helminth infection, affecting 445 million people worldwide. To better understand the impact of the immune system on the pathophysiology of individuals infected with Ascaris suum, mice have been used as experimental models. The RT-qPCR technique is a critical auxiliary tool of investigation used to quantify mRNA levels. However, proper normalization using reference genes is essential to ensure reliable outcomes to avoid analytical errors and false results. Despite the importance of reference genes for experimental A. suum infection studies, no specific reference genes have been identified yet. Therefore, we conducted a study to assess five potential reference genes (GAPDH, 18s, ACTB, B2M, and HPRT1) in different tissues (liver, lungs, small and large intestines) affected by A. suum larval migration in C57BL/6j mice. Tissue collection was carried out to analyze parasite burden and confirm the presence of larvae during the peak of migration in each tissue. Upon confirmation, we analyzed different genes in the tissues and found no common gene with stable expression. Our results highlight the importance of analyzing different genes and using different software programs to ensure reliable relative expression results. Based on our findings, B2M was ranked as the ideal reference gene for the liver, while 18S was the most stable gene in the lung and small intestine. ACTB, or a combination of ACTB with GAPDH, was deemed suitable as reference genes for the large intestine due to their stable expression and less variation between the control and infected groups. To further demonstrate the impact of using different reference genes, we normalized the expression of a chemokine gene (CXCL9) in all tissues. Significant differences in CXCL9 expression levels were observed between different groups in all tissues except for the large intestine. This underscores the importance of selecting appropriate reference genes to avoid overestimating target gene expression levels and encountering normalization-related issues that can lead to false results. In conclusion, our study highlights the significance of using reliable reference genes for accurate RT-qPCR analysis, especially in the context of A. suum infection studies in different tissues. Proper normalization is crucial to ensure the validity of gene expression data and avoid potential pitfalls in interpreting results.

Role of Silver Nanoparticles for the Control of Anthelmintic Resistance in Small and Large Ruminants

Helminths are considered a significant threat to the livestock industry, as they cause substantial economic losses in small and large ruminant farming. Their morbidity and mortality rates are also increasing day by day as they have zoonotic importance. Anthelmintic drugs have been used for controlling these parasites; unfortunately, due to the development of resistance of these drugs in helminths (parasites), especially in three major classes like benzimidazoles, nicotinic agonists, and macrocyclic lactones, their use is becoming very low. Although new anthelmintics are being developed, the process is time-consuming and costly. As a result, nanoparticles are being explored as an alternative to anthelmintics. Nanoparticles enhance drug effectiveness, drug delivery, and target specificity and have no resistance against parasites. Different types of nanoparticles are used, such as organic (chitosan) and inorganic (gold, silver, zinc oxide, iron oxide, and nickel oxide). One of them, silver nanoparticles (AgNPs), has unique properties in various fields, especially parasitology. AgNPs are synthesized from three primary methods: physical, chemical, and biological. Their primary mechanism of action is causing stress through the production of ROS that destroys cells, organs, proteins, and DNA parasites. The present review is about AgNPs, their mode of action, and their role in controlling anthelmintic resistance against small and large ruminants.

Investigating the association between intestinal parasite infection and cribra orbitalia in the medieval population of Cambridge, UK

OBJECTIVE

Cribra orbitalia is believed to be a skeletal indicator of chronic anaemia, scurvy, rickets or related metabolic diseases. It has been suggested that it may be used as a proxy indicator for intestinal parasite infection, as parasites often cause anaemia today. Our aim is to investigate this association in the medieval population of Cambridge, UK.

MATERIALS

Individuals excavated from the cemeteries of the Augustinian friary and All Saints by the Castle parish church, and aged from 7 to adulthood.

METHODS

We undertook parasite analysis of the pelvic sediment and control samples of 46 burials with intact orbital roofs.

RESULTS

Human roundworm (Ascaris lumbricoides) and/or whipworm (Trichuris trichiura) were identified in the pelvic sediment of 22 individuals, and cribra orbitalia noted in 11 individuals. Barnards test showed no association between parasite infection and cribra orbitalia (p = .882).

CONCLUSION

We found no association between infection and cribra orbitalia infection in this medieval adult population, calling into question this hypothesis, at least for adults.

SIGNIFICANCE

High or low cribra orbitalia prevalence in adults should not be used to infer rates of intestinal parasite infection.

LIMITATIONS

The individuals in the study were over the age of 7, with no younger children. It is possible that only parasites which cause marked anaemia (such as hookworm, schistosomiasis or malaria) may cause cribra orbitalia, while less marked anaemia from roundworm and whipworm may not do so.

SUGGESTIONS FOR FURTHER RESEARCH

Repeating this study in younger children, when most cribra orbitalia appears to form.

The burden of intestinal parasitic infections in Antioquia, Colombia: Impact in childhood growth development and nutritional status

Gastrointestinal protist (GP) and soil-transmitted helminth (STH) infections cause significant morbidity among children in poor-resource settings of tropical and sub-tropical countries including Colombia. Few prospective transversal studies investigating how GP and STH infections affect growth development and nutritional status during childhood have been conducted in this country, none of them in the Antioquia Department. This microscopy-based study estimated the prevalence of GP and helminth (including STH) infections in faecal samples from schoolchildren (n = 384) collected during April-May 2019 in three municipalities of the Antioquia Department. Demographic, epidemiological, and household data were elicited through face-to-face interviews. Parasite detection was carried out by direct microscopic examination of both fresh smears and concentrated faecal material. Children (aged 6-15 years) also had their haemoglobin (Hb) levels, height and weight data collected, and BMI estimated. Data were analysed using bivariate and multivariate logistic regression analysis. Overall, 60.7 % (233/384) of schoolchildren were infected by at least one intestinal parasitic species. Among GPs, Blastocystis sp. was the most common species found (47.7 %, 95 % CI: 42.6-52.8), followed by G. duodenalis (15.9 %, 95 % CI: 12.4-19.9). Cryptosporidium spp. and Cyclospora cayetanensis were sporadically identified (0.3 %, 95 % CI: 0.1-1.4 each). Among helminths, the most prevalent species found were Trichuris trichiura (6.0 %, 95 % CI: 3.8-8.9) and Enterobius vermicularis (1.0 %, 95 % CI: 0.3-2.6). Hookworms, Ascaris lumbricoides, and Strongyloides stercoralis were found at prevalence rates <1 %. Underweight, overweigh, or obese schoolchildren had 1.2 times greater chance of being infected with intestinal parasites than their counterparts with a healthy weight (P-value: 0.015). Variables significantly associated with an increased likelihood of being infected by intestinal parasites include living in a household with unfinished flouring, not wearing shoes, being in close proximity to rodents, and having improper waste disposal. Relatively simple interventional measures directed towards the improvement of household conditions, access to sanitary toilets, and promoting shoe wearing can significantly reduce childhood infections by GP and helminths in the Antioquia Department.

Pattern of anuran infection by acanthocephalans from the Cerrado, Northeastern Brazil with a summary for South America

In Brazil, acanthocephalans parasitise anurans in several biomes. In the present study, we performed an analysis of acanthocephalan infections across 175 anuran individuals from the Cerrado biome, belonging to ten species: Boana raniceps, Pithecopus hypochondrialis, Scinax fuscomarginatus, Scinax x-signatus, Leptodactylus pustulatus, Leptodactylus macrosternum, Leptodactylus vastus, Physalaemus cuvieri, Adenomera hylaedactyla, and Elachistocleis piauiensis. We also verified the specificity of the parasites using the STD* index. Additionally, we conducted a survey of acanthocephalan infection in anurans in South America. The studied assemblage in the Brazilian Cerrado presented 57 parasitised hosts of 175 specimens (overall prevalence: 32.6%). In total, 437 acanthocephalans cystacanths were recorded, among which 286 presented the same morphotype but could not be identified, 148 belonged to the genus Centrorhynchus, and three belonged to Oncicola. Unidentified acanthocephalans had a higher prevalence in L. vastus (53.85%) and the highest intensity was in L. pustulatus (17±16). The highest prevalence of Centrorhynchus sp. was in the species S. fuscomarginatus (28.57%), while the highest intensity was observed in L. vastus (111). The taxon Oncicola sp. it had a prevalence of 3.23% and an intensity of 3 only in S. x-signatus. The highest specificity was recorded for Oncicola sp. (STD*= 1), whereas the lowest was found in Centrorhynchus sp. (STD*= 2.21). Finally, according to the survey for South America, we found ten records of acanthocephalan taxa parasitizing 58 species of anurans distributed in seven countries (Brazil with the most records).

Diversity of Acanthocephala parasites in Neotropical amphibians

Acanthocephalans constitute a small taxonomic group related to rotifers and specialized in a parasitic lifestyle. Anurans act as paratenic and definitive hosts and infections always occur trophically. Our objective is to describe and summarize the richness of acanthocephalans in Neotropical anurans. We conducted a literature review in the main research databases, compiling data published until August 2021. We identified 66 articles with records of acanthocephalan-anuran association, 53.03% were carried out in Brazil. We detected 108 species of anurans from 11 families parasitized by acanthocephalans. With the exception of Bufonidae, Hylidae and Leptodactylidae, which are relatively well-studied families, interaction with acanthocephalans remains largely unexplored for most anuran species. We found six families of acanthocephalans: Centrorhynchidae, Echinorhynchidae, Oligacanthorhynchidae, Cavisomidae, Neoechinorhynchidae and Plagiorhynchidae. Centrorhynchidae and Echinorhynchidae presented the largest number of taxa associated with anurans. The largest number of records corresponded to acanthocephalans in the larval stage (cystacanths), for which anurans act as paratenic hosts. We observed a lack of specific taxonomic resolution in the identifications of most reports, because a large part of the records in the larval stage make morphological identification difficult. Brazil, Mexico, Paraguay, Argentina, Ecuador and Peru are the countries with the most records, while Costa Rica, Venezuela, Colombia, Chile and Uruguay exhibited the lowest publication numbers, resulting in gaps in the distribution of acanthocephalans. We expanded the known number of anuran species parasitized by acanthocephalans, compared to the last published review. Overall, we aim to contribute to the understanding of diversity within this intriguing but understudied group.

Parasites and Viruses in Callithrix in Brazil

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.

Development of solid lipid nanoparticles-loaded drugs in parasitic diseases

Parasites cause illnesses with broad spectrum of symptoms from mild to severe, and are responsible for a significant number of outbreaks in the world. Current anti-parasitic drugs are toxic and have significant side effects. Nano-carriers are believed to obviate the limitations of conventional drugs via decreasing side effects and increasing target delivery and drug permeability with a controlled prolonged release of a drug. Solid lipid nanoparticles (SLNs) are lipid nanoparticles (LNPs), which have frequently been practiced. Suitable release rate, stability, and target delivery make SLNs a good alternative for colloidal carriers. SLNs are supposed to have great potential to deliver natural products with anti-parasitic properties. Nanoparticles have employed to improve stability and capacity loading of SLNs, during recent years. This review describes development of SLNs, the methods of preparation, characterization, and loaded drugs into SLNs in parasitic diseases. In addition, we summarize recent development in anti-parasitic SLNs-loaded drugs.

IMPLICATIONS OF TREATING PARASITIC INFECTION IN NORTHERN BOBWHITE (COLINUS VIRGINIANUS) ON OVERALL HELMINTH LIFE CYCLE

This study was conducted to determine how reducing the parasite burden in a definitive host may affect the prevalence in intermediate hosts. Here we used the eyeworm Oxyspirura petrowi and cecal worm Aulonocephalus pennula as model species. Northern bobwhite quail (Colinus virginianus) were provided an anthelmintic medicated feed in wild systems because of convincing evidence that these parasites were suppressing their populations. Eyeworm and cecal worm prevalence were measured in Orthopterans, which act as intermediate hosts, using polymerase chain reaction. Individuals were collected from a control site, a site treated for 2 yr, and a site treated for 5 yr. Orthopteran community composition was significantly different among the sites; however, an interaction between subfamily and site was not significant for the eyeworm. There was a significant reduction in eyeworm-infected Orthopterans on the 5-yr site compared with the other 2, suggesting that treatment of a definitive host may indeed affect the prevalence of eyeworms during other life-cycle stages. There was an interaction between the Orthopteran subfamily and the site for the cecal worm, so results were analyzed within each subfamily. A significant reduction in the prevalence of cecal worms was only found in the Cyrtacanthacridinae subfamily on the 5-yr site when compared with the other sites. However, the greatest prevalence in the Gomphocerinae and Oedipodinae subfamilies across all 3 sites was 4.1%. This indicates an unknown degree of cecal worm host specificity. Therefore, conclusions could not be made through the simple assessment of prevalence.

Intestinal Parasitic Infections in People Referring to the Central Laboratory of Meshkin Shahr County, Ardabil Province, Iran

Background

Intestinal parasitic infections are still a considerable global public health problem. We aimed to determine the frequency of intestinal parasitic infections among people referring to the central laboratory of Meshkin Shahr City, Ardabil Province, Iran.

Methods

In this cross-sectional survey, 460 fecal samples were collected randomly from persons referred to the central laboratory of Meshkin Shahr City, from January to June 2022. The samples were examined by direct wet-mount, Trichrome and modified Ziehl-Neelsen staining, formalin ethyl acetate sedimentation, and agar plate culture.

Results

The frequency of intestinal parasites was 15.7% (72 out of 460 cases), with some people with numerous intestinal parasites. The frequency of protozoan infections (13.9%) was higher than the helminthic infections (2.6%). Blastocystis spp. (8.1%) was the most prevalent detected intestinal protozoan. Entamoeba coli (5.7%), Dicrocoelium dendriticum (2.2%), Giardia lamblia (1.5%), Fasciola spp. (0.2%), and Hymenolepis nana (0.2%) were other detected parasites.

Conclusion

In- spite of betterment of the health condition in Iran and reduction of parasitic infection, intestinal parasitic infections are still a considerable public health issue in some parts of Iran.

Parasites in ancient Egypt and Nubia: Malaria, schistosomiasis and the pharaohs

The civilizations of ancient Egypt and Nubia played a key role in the cultural development of Africa, the Near East, and the Mediterranean world. This study explores how their location along the River Nile, agricultural practices, the climate, endemic insects and aquatic snails impacted the type of parasites that were most successful in their populations. A meta-analysis approach finds that up to 65% of mummies were positive for schistosomiasis, 40% for headlice, 22% for falciparum malaria, and 10% for visceral leishmaniasis. Such a disease burden must have had major consequences upon the physical stamina and productivity of a large proportion of the workforce. In contrast, the virtual absence of evidence for whipworm and roundworm (so common in adjacent civilizations in the Near East and Europe) may have been a result of the yearly Nile floods fertilising the agricultural land, so that farmers did not have to fertilise their crops with human faeces.

Helminth fauna of the black goby Gobius niger L. (Gobiiformes: Gobiidae) from the Finnish Archipelago, Baltic Sea: Molecular and morphological data

Black gobies (Gobius niger) from the Finnish Archipelago, Baltic Sea, were screened for helminth infections in summer 2020. Helminths were identified morphologically and/or molecularly. Altogether 26 novel sequences were generated and analysed using maximum likelihood estimation. Morphological and phylogenetic analyses based on mitochondrial genes revealed the presence of 8 species belonging to the Digenea (Diplostomum mergi Lineage 3), Cestoda (Bothriocephalus scorpii), Nematoda (Contracaecum rudolphii A, Cucullanus sp. and Hysterothylacium aduncum), and Acanthocephala (a putative new species of Corynosoma, Corynosoma semerme and Neoechinorhynchus sp.). Phylogenetic and comparative sequence analyses revealed that the putative new acanthocephalan species is closely related to C. neostrumosum described from the Caspian seal, Pusa caspica, in the Caspian Sea. The black goby represents a new host record for four parasite species (Diplostomum mergi Lineage 3, Contracaecum rudolphii A, Corynosoma semerme and Corynosoma sp.). The Finnish Archipelago is a novel locality record for three species (Corynosoma sp., Diplostomum mergi Lineage 3 and Bothriocephalus scorpii).

Impact of anthropogenous environmental factors on the marine ecosystem of trophically transmitted helminths and hosting seabirds: Focus on North Atlantic, North Sea, Baltic and the Arctic seas

Alongside natural factors, human activities have a major impact on the marine environment and thus influence processes in vulnerable ecosystems. The major purpose of this review is to summarise the current understanding as to how manmade factors influence the marine biocenosis of helminths, their intermediate hosts as well as seabirds as their final hosts. Moreover, it highlights current knowledge gaps regarding this ecosystem, which should be closed in order to gain a more complete understanding of these interactions. This work is primarily focused on helminths parasitizing seabirds of the North Atlantic and the Arctic Ocean. The complex life cycles of seabird helminths may be impacted by fishing and aquaculture, as they interfere with the abundance of fish and seabird species, while the latter also affects the geographical distribution of intermediate hosts (marine bivalve and fish species), and may therefore alter the intertwined marine ecosystem. Increasing temperatures and seawater acidification as well as environmental pollutants may have negative or positive effects on different parts of this interactive ecosystem and may entail shifts in the abundance or regional distribution of parasites and/or intermediate and final hosts. Organic pollutants and trace elements may weaken the immune system of the hosting seabirds and hence affect the final host's ability to control the endoparasites. On the other hand, in some cases helminths seem to function as a sink for trace elements resulting in decreased concentrations of heavy metals in birds' tissues. Furthermore, this article also describes the role of helminths in mass mortality events amongst seabird populations, which beside natural causes (weather, viral and bacterial infections) have anthropogenous origin as well (e.g. oil spills, climate change, overfishing and environmental pollution).

Diversity, prevalence and risk factors associated to gastrointestinal tract parasites in wild and domestic animals from Pakistan

The gastrointestinal tract (GIT) of animals contains various helminth parasites, responsible for subclinical and clinical parasitism. The health situation of animals is seriously affected by these parasites and leads massive financial losses for the livestock trade. The present study was conducted to determine the prevalence and associated risk factors of GIT parasites in small and large ruminants of Mardan district and zoo animals of Golden Life Safari Park Khyber Pakhtunkhwa. A total of 419 fecal samples were collected including 117 from goats, 110 from cattle, 80 from sheep, 66 from buffaloes, 40 from birds, four from deer, and two from leopards. The fecal samples were subjected to sedimentation and floatation to identify parasite eggs. Of a total of 419 fecal samples, 215 (51.31%) were found positive for GIT parasites eggs. The prevalence of GIT parasites was high in sheep (65%), followed by goats (62.39%), cattle (42.70%), and buffaloes (37.87%). In birds, GIT parasite eggs were identified in 11 (45.83%) and 7 (43.75%) fecal samples of Pheasant and Peacock, respectively. However, an absence of infection was noted in fecal samples from deer and leopards. Eggs of GIT Parasites belonging to one superfamily and four different genera were recognized in fecal samples of domestic animals and buffaloes, which were Trichostrongyloidea (19.81%), Strongyloides (9.31%), Trichuris (7.77%), Monezia (6.44%), and Fasciola (4.53%). For bird, the coccidia group comprises the highest representation of parasites (2.63%), followed by the Trichuris genus (1.67%). Settlement, management system, anthelminthic medications and body condition score were significantly associated with the occurrence of GIT parasites in feces (P < 0.05). Animals from rural settlements, rearing under poor management systems, with thin (poor) body condition and under warmed were more affected by GIT parasites. The diversity and the high prevalence of GIT parasites reported in this study highlights the urgent need for intervention through treatment and modification of management practices in the investigated areas of Pakistan.

Gastro-intestinal parasites of urban rhesus macaques (Macaca mulatta) in the Kathmandu Valley, Nepal

Intestinal parasitic infections such as amoebiasis, ascariasis, hookworm infection, and trichuriasis are the most common infections among non-human primates (NHPs). There are always the possibilities of transmission these parasites between humans and NHPs. Multiple groups of rhesus macaques (Macaca mulatta) live in the urban area of Kathmandu Valley near human settlements, however the gastrointestinal (GI) parasitic infections in those macaques are understudied. This study aimed to explore the GI parasites in free-ranging macaques from Pashupatinath, Swayambhunath, Tripureshwor, Nilbarahi temples and a group of captive rhesus macaques in the Central Zoo, Kathmandu. Fecal samples were collected from the macaques between October 2021 to September 2022 and assessed for parasites by the both wet mount method and concentration technique. There is high prevalence of GI parasite infection; out of 121 fecal samples examined, 87.6% of samples were positive. Six species of protozoans and eight species of helminths were identified from the fecal samples including the first report of Iodamoeba butschlii in monkeys of Nepal. Among the protozoan parasites, Entamoeba coli (54.71%) showed the highest prevalence followed by Balantioides coli (44.33%), E. histolytica (19.81%), and Iodamoeba butschlii (10%). Among the helminths, Trichuris spp. (31.13%) and Strongyloides spp. (31.13%) showed the highest prevalence followed by Hookworm (24.52%), and Strongyle spp. (23.58%). The likelihood ratio test suggested that the prevalence differed significantly with the seasons for Iodamoeba butschlii, Giardia spp., Strongyles spp., Hookworm, and Trichostrongylus spp. The prevalence of E. histolytica, E. coli, Iodamoeba. butschlii, Trichuris spp., Trichostrongylus spp., and Unknown spp.1 differed with sampling localities. The high prevalence of GI parasites found in the macaques living in the densely urbanized Kathmandu presents a potential threat to humans and warrants further study as well as increased education of the public and management of the human-macaque interface in the urban landscape of the Valley.

SARCOCYSTIS AND OTHER PARASITES IN FECES OF BOBCATS (LYNX RUFUS) FROM MISSISSIPPI

Rectal contents of 56 adult bobcats (Lynx rufus) in 2014 and 2017 from remote areas of Mississippi were examined microscopically for parasite stages after the sugar flotation method. Among the helminths, eggs/larvae found were: Paragonimus sp. in 12, Toxocara cati-like in 16, trichurid-capillarid-like in 3, hookworms in 27, and lungworms in 28. Among the protozoa, oocysts/cysts found were: Cystoisospora felis-like in 2, Cystoisospora rivolta-like in 4, Cryptosporidium sp. in 1, and Giardia sp. in 1. Additionally, numerous Sarcocystis sporocysts were detected in the feces of 12 bobcats; sporocysts were described morphologically. The status of C. felis derived from the bobcat and other wild felids is reviewed and compared with C. felis from the domestic cat. It is the first record of C. rivolta from the bobcat. The presence of eggs of Paragonimus sp. and T. cati in feces of 21.4% and 28.5%, respectively, suggests a role for the bobcat in the dissemination of these zoonotic helminths in the environment in the wild. Taxonomy of coccidia of wild Felidae is discussed and Isospora lyncisLevine and Ivens, 1981 from the Lynx is now regarded as a species inquirenda.

Intestinal Helminthiasis: Risk factors and relationship with Nutritional status and Anaemia among Institutionalised Children in three States of South-East Nigeria

BACKGROUND

Intestinal helminthiasis occurs in sub-optimal living conditions with poor hygiene practices and is more prevalent in rural, suburban and institutionalized centres. Heavy helminthic burden negatively affects the nutritional status and the severity of anaemia among children living in orphanages.

AIM

To determine the risk factors and relationship of intestinal helminthiasis with nutritional status and anaemia among institutionalized children in three states of South-East Nigeria.

METHODS

A cross-sectional study was conducted over seven months involving 198 children recruited from orphanages in Anambra, Ebonyi and Enugu states. Their stool samples were analyzed using the Kato-Katz and Ether concentration techniques, and packed cell volume and anthropometric indices were documented. Data were analyzed.

RESULTS

Of the 198 children, 109 (55.1%) were females with a median age of 2.5 years and interquartile range (3 months - 17 years). The prevalence of intestinal helminthiasis was 2.5%. Among the children that had intestinal helminthiasis, 4 (80%) had mono-parasitism with Ascaris lumbricoides, while 1 (20%) had mixed infestation of Ascaris lumbricoides and Trichuris trichiura. There was a significant association (p=0.01) between being infested with intestinal helminthiasis and caregiver handwashing practices. The anthropometric indices demonstrated that 5.6%, 6.6% and 13.1% of the children were underweight, wasted and stunted respectively. No helminth-infested child had malnutrition and only 1 (20%) infested child had moderate anaemia.

CONCLUSION

Caregivers' good handwashing practice was associated with reduced prevalence of intestinal infestations and should be encouraged. There was no relationship found between the presence of helminthic infestations and nutritional status or anaemia among the institutionalised children.

1H-NMR based-metabolomics reveals alterations in the metabolite profiles of chickens infected with ascarids and concurrent histomonosis infection

BACKGROUND

Gut infections of chickens caused by Ascaridia galli and Heterakis gallinarum are associated with impaired host performance, particularly in high-performing genotypes. Heterakis gallinarum is also a vector of Histomonas meleagridis that is often co-involved with ascarid infections. Here, we provide a first insight into the alteration of the chicken plasma and liver metabolome as a result of gastrointestinal nematode infections with concomitant histomonosis. 1H nuclear magnetic resonance (1H-NMR) based-metabolomics coupled with a bioinformatics analysis was applied to explore the variation in the metabolite profiles of the liver (N = 105) and plasma samples from chickens (N = 108) experimentally infected with A. galli and H. gallinarum (+H. meleagridis). This was compared with uninfected chickens at different weeks post-infection (wpi 2, 4, 6, 10, 14, 18) representing different developmental stages of the worms.

RESULTS

A total of 31 and 54 metabolites were quantified in plasma and aqueous liver extracts, respectively. Statistical analysis showed no significant differences (P > 0.05) in any of the 54 identified liver metabolites between infected and uninfected hens. In contrast, 20 plasma metabolites including, amino acids, sugars, and organic acids showed significantly elevated concentrations in the infected hens (P < 0.05). Alterations of plasma metabolites occurred particularly in wpi 2, 6 and 10, covering the pre-patent period of worm infections. Plasma metabolites with the highest variation at these time points included glutamate, succinate, trimethylamine-N-oxide, myo-inositol, and acetate. Differential pathway analysis suggested that infection induced changes in (1) phenylalanine, tyrosine, and tryptophan metabolism, (2) alanine, aspartate and glutamate metabolism; and 3) arginine and proline metabolism (Pathway impact > 0.1 with FDR adjusted P-value < 0.05).

CONCLUSION

In conclusion, 1H-NMR based-metabolomics revealed significant alterations in the plasma metabolome of high performing chickens infected with gut pathogens-A. galli and H. gallinarum. The alterations suggested upregulation of key metabolic pathways mainly during the patency of infections. This approach extends our understanding of host interactions with gastrointestinal nematodes at the metabolic level.

Integrated morphological and molecular characterization of the fish parasitic nematode Rhabdochona (Rhabdochona) gendrei Campana-Rouget, 1961 infecting Labeobarbus altianalis (Boulenger, 1900) in Kenya

During a parasitological survey carried out between May and August 2022 in the River Nyando, Lake Victoria Basin, a single species of Rhabdochona Railliet, 1916 (Nematoda: Rhabdochonidae) was recorded from the intestine of the Rippon barbel, Labeobarbus altianalis (Boulenger, 1900) (Cyprinidae). Based on light microscopy (LM), scanning electron microscopy (SEM) and DNA analyses the parasite was identified as Rhabdochona (Rhabdochona) gendrei Campana-Rouget, 1961. Light microscopy, SEM and DNA studies on this rhabdochonid resulted in a detailed redescription of the adult male and female. The following additional taxonomic features are described in the male: 14 anterior prostomal teeth; 12 pairs of preanal papillae: 11 subventral and one lateral; six pairs of postanal papillae: five subventral and one lateral, with the latter pair at the level of first subventral pairs when counted from the cloacal aperture. For the female: 14 anterior prostomal teeth and the size and absence of superficial structures on fully mature (larvated) eggs dissected out of the nematode body. Specimens of R. gendrei were genetically distinct in the 28S rRNA and cytochrome c oxidase subunit 1 (cox1) mitochondrial gene regions from known species of Rhabdochona. This is the first study that provides genetic data for a species of Rhabdochona from Africa, the first SEM of R. gendrei, and the first report of this parasite from Kenya. The molecular and SEM data reported herein provide a useful point of reference for future studies on Rhadochona in Africa.

A survey of the parasites of Ural saiga antelopes and Turkmenian kulans of Kazakhstan

Saiga antelope and Turkmenian kulans are considered critically endangered and near threatened, respectively, by the International Union for Conservation of Nature (IUCN). Due to these species' fragile status, it is important to understand the pathogens infecting their remaining populations. A total of 496 faecal samples were collected from Ural saiga antelope in western Kazakhstan during June, September, and November of 2021 and May and August of 2022 and 149 faecal samples were collected from kulans in the Altyn-Emel nature reserve in south-eastern Kazakhstan from June to August of 2021. Additionally, endo- and ecto-parasites were collected from 17 saiga that were found deceased due to natural causes. Nine helminths (3 cestodes, 6 nematodes) and two protozoans were found in Ural saiga antelope. In addition to intestinal parasites, one case of cystic echinococcosis due to Echinococcus granulosus infection and one case of cerebral coenurosis due to Taenia multiceps infection was identified on necropsy. None of the collected ticks (all Hyalomma scupense) were found positive for Theileria annulate (enolase gene) or Babesia spp. (18 S ribosomal RNA gene) via PCR. Three intestinal parasites (Parascaris equorum, Strongylus sp., and Oxyuris equi) were found in kulans. All identified parasites, in both saiga and kulans, are also found in domesticated livestock, suggesting a need for better understanding of how parasites are maintained within and between regional wild and domestic ungulate populations.

Cancerogenic parasites in veterinary medicine: a narrative literature review

Parasite infection is one of the many environmental factors that can significantly contribute to carcinogenesis and is already known to be associated with a variety of malignancies in both human and veterinary medicine. However, the actual number of cancerogenic parasites and their relationship to tumor development is far from being fully understood, especially in veterinary medicine. Thus, the aim of this review is to investigate parasite-related cancers in domestic and wild animals and their burden in veterinary oncology. Spontaneous neoplasia with ascertained or putative parasite etiology in domestic and wild animals will be reviewed, and the multifarious mechanisms of protozoan and metazoan cancer induction will be discussed.

External and gastrointestinal parasites of the black-faced ibis Theristicus melanopis (Pelecaniformes: Threskiornithidae) in the Los Ríos region, southern Chile

The black-faced ibis, Theristicus melanopis, is considered a useful bird species for agricultural activity because it preys upon various invertebrate and vertebrate pests. Although it is a common species in Chile, limited information is available regarding its parasites. The main objective of this study was to recover the diversity of ectoparasites and gastrointestinal helminths in black-faced ibises living in the communes of Valdivia and Panguipulli, Los Ríos region. A total of 74 specimens were received for examination from the Centro de Rehabilitación de Fauna Silvestre at the Universidad Austral de Chile (CEREFAS-UACh), Valdivia, in 2011-2015. Black-faced ibises were externally inspected for ectoparasites by direct examining of the plumage, and necropsies were performed to examine digestive and respiratory organs in search of endoparasites. For each taxon, prevalence, mean intensity, mean abundance, and range of parasites per bird were estimated. Five species of ectoparasites and six species of helminths were identified. A total of 298 lice (Insecta: Phthiraptera) belonging to four species were collected: Ardeicola melanopis (13.51%), Colpocephalum trispinum (20.27%), Ibidoecus fissisignatus (4.05%), and Plegadiphilus mamillatus (9.46%). In addition, one feather mite species, Diodochaetus melanopis (Acari: Pterolichoidea) (17.56%), was isolated. In 48 black-faced ibis (64.86%), a total of 1229 gastrointestinal helminths were found: two nematodes, Porrocaecum heteropterum (55.41%) and Baruscapillaria obsignata (24.32%); one tapeworm Eugonodaeum nasuta (20.27%); two digeneans, Echinoparyphium recurvatum (1.35%) and Strigea bulbosa (6.76%); and the acanthocephalan Sphaerirostris sp. (1.35%). The findings of the following parasites present new host-parasite associations: P. mamillatus, D. melanopis, B. obsignata, E. recurvatum, S. bulbosa, and Sphaerirostris sp. Additionally, the louse P. mamillatus, feather mite D. melanopis, platyhelminths E. nasuta, E. recurvatum and S. bulbosa, and the acanthocephalan Sphaerirostris sp. are new records for the fauna of Chile.

Transcriptome Profiling of Male Adult Angiostrongylus cantonensis

Background

The pathogen of angiostrongyliasis is the parasite Angiostrongylus cantonensis, and the transcriptome profiling of the male adult was unclear. We aimed to understand how the male adults adapt, so the expression profile of A. cantonensis adult males was analyzed.

Methods

In order to improve the understanding of the transcriptome of adult males, RNA from three groups of male adult A. cantonensis was extracted and reverse transcribed to construct cDNA libraries. After sequencing, annotation of unigenes and transcripts was performed by querying the NR (Non-Redundant Protein Sequence Database), GO (Gene Ontology) and COG/KOG (Clusters of Orthologous Groups of proteins/euKaryotic Ortholog Groups) databases.

Results

For each group of adults, 43,260,894 raw reads and 43,200,341 clean reads were obtained. After successful assembly, 87,649 unigenes and 146,895 transcripts were obtained. Annotation of the unigenes and transcripts was identical and male adults expressed a series of genes encoding proteins specific to the male gender at the adult stage, such as proteins involved in energy metabolism, energy synthesis and transport. Expression of the ribosome pathway suggests a relationship with the physical activities during the adult male stage.

Conclusion

The transcriptome analysis is a good reference to understand further the expression profile of male adult A. cantonensis.

INTESTINAL PARASITES IN PECARI TAJACU AND SUS SCROFA DOMESTICUS IN THE CAATINGA FROM SOUTHEASTERN PIAUÍ, BRAZIL

This study identifies gastrointestinal parasites in the feces of Pecari tajacu (caititu) and Sus scrofa domesticus (domestic pig) in southeastern Piauí, Brazil. The region covers 2 protected areas, Serra da Capivara National Park and Serra das Confusões National Park, and surrounding communities. Fecal samples from 64 animals, 42 from domestic swine and 22 from caititu, collected between 1985 and 2013, were analyzed by optical microscopy. Helminths and/or protozoa were found in 64% of the domestic pig samples and 27% of the caititu samples, totaling 18 morphospecies: Nematoda, Spirurida (2 morphospecies), Trichostrongyloidea, Eimeriidae, Aspidodera sp., Bertiella sp., Metastrongylus sp., Trichostrongylus sp., Moniezia sp., Gongylonema sp., Trichuris suis, Spirocerca lupi, Macracanthorhyncus hirudinaceus, Globocephalus urosubulatus, Strongyloides cf ransomi, Balantioides coli, and Eimeria cf scabra. The highest parasite diversity was obtained in the pig samples, totaling 15 morphospecies, compared to only 6 in caititus, with S. cf ransomi, G. urosubulatus, and S. lupi present in both hosts. We discuss the presence of parasites associated with domestic animals around the Protected Areas and potentially zoonotic parasites close to human communities, which raise concerns about the conservation of wildlife, human health, and livestock in the region.

An insight into the functional genomics and species classification of Eudiplozoon nipponicum (Monogenea, Diplozoidae), a haematophagous parasite of the common carp Cyprinus carpio

BACKGROUND

Monogenea (Platyhelminthes, Neodermata) are the most species-rich class within the Neodermata superclass of primarily fish parasites. Despite their economic and ecological importance, monogenean research tends to focus on their morphological, phylogenetic, and population characteristics, while comprehensive omics analyses aimed at describing functionally important molecules are few and far between. We present a molecular characterisation of monogenean representative Eudiplozoon nipponicum, an obligate haematophagous parasite infecting the gills of the common carp. We report its nuclear and mitochondrial genomes, present a functional annotation of protein molecules relevant to the molecular and biochemical aspect of physiological processes involved in interactions with the fish hosts, and re-examinate the taxonomic position of Eudiplozoon species within the Diplozoidae family.

RESULTS

We have generated 50.81 Gbp of raw sequencing data (Illumina and Oxford Nanopore reads), bioinformatically processed, and de novo assembled them into a genome draft 0.94 Gbp long, consisting of 21,044 contigs (N50 = 87 kbp). The final assembly represents 57% of the estimated total genome size (~ 1.64 Gbp), whereby repetitive and low-complexity regions account for ~ 64% of the assembled length. In total, 36,626 predicted genes encode 33,031 proteins and homology-based annotation of protein-coding genes (PCGs) and proteins characterises 14,785 (44.76%) molecules. We have detected significant representation of functional proteins and known molecular functions. The numbers of peptidases and inhibitors (579 proteins), characterised GO terms (16,016 unique assigned GO terms), and identified KEGG Orthology (4,315 proteins) acting in 378 KEGG pathways demonstrate the variety of mechanisms by which the parasite interacts with hosts on a macromolecular level (immunomodulation, feeding, and development). Comparison between the newly assembled E. nipponicum mitochondrial genome (length of 17,038 bp) and other diplozoid monogeneans confirms the existence of two distinct Eudiplozoon species infecting different fish hosts: Cyprinus carpio and Carassius spp.

CONCLUSIONS

Although the amount of sequencing data and characterised molecules of monogenean parasites has recently increased, a better insight into their molecular biology is needed. The E. nipponicum nuclear genome presented here, currently the largest described genome of any monogenean parasite, represents a milestone in the study of monogeneans and their molecules but further omics research is needed to understand these parasites' biological nature.

Metabolomics and lipidomics studies of parasitic helminths: molecular diversity and identification levels achieved by using different characterisation tools

INTRODUCTION

Helminths are parasitic worms that infect millions of people worldwide and secrete a variety of excretory-secretory products (ESPs), including proteins, peptides, and small molecules. Despite this, there is currently no comprehensive review article on cataloging small molecules from helminths, particularly focusing on the different classes of metabolites (polar and lipid molecules) identified from the ESP and somatic tissue extracts of helminths that were studied in isolation from their hosts.

OBJECTIVE

This review aims to provide a comprehensive assessment of the metabolomics and lipidomics studies of parasitic helminths using all available analytical platforms.

METHOD

To achieve this objective, we conducted a meta-analysis of the identification and characterization tools, metabolomics approaches, metabolomics standard initiative (MSI) levels, software, and databases commonly applied in helminth metabolomics studies published until November 2021.

RESULT

This review analyzed 29 studies reporting the metabolomic assessment of ESPs and somatic tissue extracts of 17 helminth species grown under ex vivo/in vitro culture conditions. Of these 29 studies, 19 achieved the highest level of metabolite identification (MSI level-1), while the remaining studies reported MSI level-2 identification. Only 155 small molecule metabolites, including polar and lipids, were identified using MSI level-1 characterization protocols from various helminth species. Despite the significant advances made possible by the 'omics' technology, standardized software and helminth-specific metabolomics databases remain significant challenges in this field. Overall, this review highlights the potential for future studies to better understand the diverse range of small molecules that helminths produce and leverage their unique metabolomic features to develop novel treatment options.

Comparative biology of parasitic nematodes in the genus Angiostrongylus and related genera

The rise to prominence of some Angiostrongylus species through associated emerging disease in humans and dogs has stimulated calls for a renewed focus on the biology of this genus and three related genera. Although significant research efforts have been made in recent years these have tended to focus on individual species and specific aspects such as diagnosis and treatment of disease or new records of occurrence and hosts. This comprehensive review takes a comparative approach, seeking commonalities and differences among species and asking such questions as: Which species belong to this and to closely related genera and how are they related? Why do only some species appear to be spreading geographically and what factors might underlie range expansion? Which animal species are involved in the life cycles as definitive, intermediate, paratenic and accidental hosts? How do parasite larvae find, infect and develop within these hosts? What are the consequences of infection for host health? How will climate change affect future spread and global health? Appreciating how species resemble and differ from each other shines a spotlight on knowledge gaps and provides provisional guidance on key species characteristics warranting detailed study. Similarities exist among species, including the basic life cycle and transmission processes, but important details such as host range, climatic requirements, migration patterns within hosts and disease mechanisms differ, with much more information available for A. cantonensis and A. vasorum than for other species. Nonetheless, comparison across Angiostrongylus reveals some common patterns. Historically narrow definitive host ranges are expanding with new knowledge, combining with very broad ranges of intermediate gastropod hosts and vertebrate and invertebrate paratenic and accidental hosts to provide the backdrop to complex interactions among climate, ecology and transmission that remain only partly understood, even for the species of dominant concern. Key outstanding questions concern larval dynamics and the potential for transmission outside trophic relations, relations between infection and disease severity in different hosts, and how global change is altering transmission beyond immediate impacts on development rate in gastropods. The concept of encounter and compatibility filters could help to explain differences in the relative importance of different gastropod species as intermediate hosts and determine the importance of host community composition and related environmental factors to transmission and range. Across the group, it remains unclear what, physiologically, immunologically or taxonomically, delimits definitive, accidental and paratenic hosts. Impacts of infection on definitive host fitness and consequences for population dynamics and transmission remain mostly unexplored across the genus. Continual updating and cross-referencing across species of Angiostrongylus and related genera is important to synthesise rapid advances in understanding of key traits and behaviours, especially in important Angiostrongylus species that are emerging causative agents of disease in humans and other animals.

The Association of Sanitation and Hygiene Practices With Intestinal Parasitic Infections Among Under-14 Children in Rural Dire Dawa, Eastern Ethiopia: A Community Based Cross-sectional Study

Background

Intestinal parasitic infections (IPIs) are neglected tropical diseases. Sanitation and hygiene are vital components for achieving sustainable control of intestinal parasitic infections. Children are the most vulnerable to intestinal parasitic infections because of their immature immune systems and frequent exposure to unsanitary environments. The aim of this study was to assess the magnitude of IPIs and associated risk factors, including sanitation and hygiene practices, among under-14-year-old children in rural Dire Dawa, eastern Ethiopia.

Methods

This community-based cross-sectional 'study included 778 subjects aged 1 to 14 years. Data were collected using questionnaires and stool examinations. The direct wet-mount method and formol-ether concentration techniques were performed to identify IPIs. Data Analysis: A descriptive statistic was used to show the prevalence of IPIs. Bi-variable and multivariable analysis using the logistic regression model was carried out.

Results

The outputs are presented using an adjusted odds ratio (aOR) with 95% confidence intervals (CIs). The prevalence of 5 intestinal parasites was 33.7% (95% CI = 30.4%-37%). Giardia intestinalis (15.2%) and Hymenolepis nana (11.6%) had the highest prevalence. The odds of IPIs among children of illiterate mothers were 13.1 times higher when compared with children of mothers with secondary education (aOR = 13.1, P = .02), and the odds of IPIs among children from households that have unclean latrines were 1.8 times higher when compared with children from households that have clean latrines. (aOR = 1.8, P = .03). Children from households that discard solid waste in open fields had 1.7 times higher odds of having a positive result than children from households that burn their waste (aOR = 1.7, P = .03). However, children without a swimming habit (aOR = 0.4, P = .000) and asymptomatic children (aOR = 0.3, P = .000) were protective against IPIs.

Conclusions

IPIs continue to be a public health problem in rural parts of Dire Dawa. The prevalence of Giardia intestinalis and H. nana could be of public health importance in this setting. Solid waste management, latrine cleanliness, mothers' level of education, and child swimming habits in unclean accumulated water were significantly associated with IPIs. Therefore, efforts should be made to ensure intervention, considering such risks.

The "parasite detoxification hypothesis": lead exposure potentially changes the ecological interaction from parasitism to mutualism

In urban areas, organisms are exposed to high pollutant levels, especially element trace metals that may impact host-parasite interactions. Indeed, parasites have been reported to reduce the negative effects of pollutants on their hosts. The fitness of parasitized organisms in polluted environments may therefore be greater than that of unparasitized organisms. In our study, we used an experimental approach to test this hypothesis on feral pigeons (Columba livia), which are endemically parasitized by nematodes and exposed to high levels of lead in urban areas. We tested the combined effects of lead exposure and helminth parasitism on different pigeon fitness components: preening, immunocompetence, abundance of lice (Columbicola columbae) and haemosporidian parasites (Heamoproteus spp., Plasmodium spp.), reproduction investment, and oxidative stress. Our results show that among pigeons exposed to lead treatment, individuals harboring nematode parasites exhibit more preening activity and have fewer ectoparasites lice than nematode-free individuals. Benefits for nematode-parasitized individuals exposed to lead were not detected for other fitness parameters. Further studies are required to confirm the "parasite detoxification hypothesis" in pigeons and to identify the mechanisms by which this detoxification occurs.

Pattern and repeatability of ascarid-specific antigen excretion through chicken faeces, and the diagnostic accuracy of coproantigen measurements as compared with McMaster egg counts and plasma and egg yolk antibody measurements in laying hens

BACKGROUND

A coproantigen enzyme-linked immunosorbent assay (ELISA) has recently been proposed for detecting ascarid infections in chickens. The excretion pattern of ascarid antigens through chicken faeces and the consistency of measurements over the course of infections are currently unknown. This study evaluates the pattern and repeatability of worm antigen per gram of faeces (APG) and compares the diagnostic performance of the coproantigen ELISA with a plasma and egg yolk antibody ELISA and McMaster faecal egg counts (M-FEC) at different weeks post-infection (wpi).

METHODS

Faecal, blood and egg yolk samples were collected from laying hens that were orally infected with a mix of Ascaridia galli and Heterakis gallinarum eggs (N = 108) or kept as uninfected controls (N = 71). Measurements including (a) APG using a coproantigen ELISA, (b) eggs per gram of faeces (EPG) using the McMaster technique and (c) ascarid-specific IgY in plasma and in egg yolks using an ascarid-specific antibody ELISA) were performed between wpi 2 and 18.

RESULTS

Time-dependent significant differences in APG between infected and non-infected laying hens were quantified. At wpi 2 (t₍₁₆₄₎ = 0.66, P = 1.00) and 4 (t₍₁₆₄₎ = -3.09, P = 0.094) no significant differences were observed between the groups, whereas infected hens had significantly higher levels of APG than controls by wpi 6 (t₍₁₆₄₎ =  -6.74, P < 0.001). As indicated by a high overall repeatability estimate of 0.91 (CI = 0.89-0.93), APG could be measured consistently from the same individual. Compared to McMaster and antibody ELISA, coproantigen ELISA showed the highest overall diagnostic performance (area under curve, AUC = 0.93), although the differences were time-dependent. From wpi 6 to 18 coproantigen ELISA had an AUC > 0.95, while plasma IgY ELISA showed the highest diagnostic performance in wpi 2 (AUC = 0.95). M-FEC had the highest correlation with total worm burden, while APG had highest correlations with weights and lengths of A. galli.

CONCLUSION

Ascarid antigen excretion through chicken faeces can be measured with high accuracy and repeatability using a coproantigen ELISA. The antigen excretion increases over time, and is associated with worm maturation, particularly with the size of A. galli. Our results suggest the necessity of complementary use of different diagnostic tools for a more accurate diagnosis of infections.

Anthelmintic resistance of horse strongyle nematodes to ivermectin in São Paulo state, Brazil

The indiscriminate use of drugs to control gastrointestinal helminths in horses can lead to serious consequences for the animals, which represents a growing problem for health, animal welfare and productivity. Therefore, the present study aimed to evaluate the anthelmintic efficacy of ivermectin in naturally infected horses in the western region of the state of São Paulo. From May 2021 to April 2022, 123 naturally infected adult horses in 12 equine breeding farms (7 to 14 animals per farm) were evaluated with the fecal egg count reduction test. The horses had not been treated with anthelmintic drugs for at least 60 days before the start of the study. The animals were treated with ivermectin (0.2 mg/kg; Eqvalan®, Merial) administered orally according to recommended dosage by the manufacturer. Individual fecal samples were collected directly from the rectal ampulla and used to determine the eggs per gram of feces (EPG) and perform coproculture for identification of larvae on the day of anthelmintic treatment (D0) and 14 days later (D14). The fecal egg count reduction (FECR) on each property was calculated using the program Shiny-egg Counts R version 3.6.1, and the presence of anthelmintic resistance was confirmed when the FECR percentage was less than 95%, and when the lower confidence limit [LCI] was less than 90%. The pre-treatment average EPG count in the 12 properties was 991. In five properties the FECR was lower than 90%; in three properties between 90% and 95%; and in four properties equal to or greater than 95% after treatment with ivermectin. The occurrence of cyathostomins with resistance to ivermectin was recorded in the majority of the farms.

Continuity in intestinal parasite infection in Aalst (Belgium) from the medieval to the early modern period (12th-17th centuries)

OBJECTIVE

To characterize patterns in the taxonomic diversity of parasites infecting the population of Aalst, Belgium, between the 12th and 17th centuries.

MATERIALS

14 sediment samples from seven cesspits dated 1100-1700 CE.

METHODS

Digital light microscopy and Enzyme-linked immunosorbent assay (ELISA).

RESULTS

We identified eggs of four species of helminths: whipworm (Trichuris trichiura), roundworm (Ascaris lumbricoides), Echinostoma fluke and Dicrocoelium fluke. ELISA results for protozoal parasites were negative.

CONCLUSIONS

Taxonomic diversity of parasite infections remained constant from the 12th to the 17th centuries. Roundworm and whipworm, spread by poor sanitation, were dominant. Two species of zoonotic parasites were also identified, including for the first time ever in the Low Countries the Echinostoma fluke, which may have been spread by eating uncooked freshwater animal foods.

SIGNIFICANCE

Analysis of sediment samples spanning such a broad chronology (six centuries) from a single city offers the opportunity to track diachronic change, which is rare in paleoparasitological studies.

LIMITATIONS

We were unable to acquire samples from cesspits dating to the 14th century.

SUGGESTIONS FOR FURTHER RESEARCH

Additional data from other Low Countries towns may strengthen the patterns identified in this paper. A similar approach can be used to investigate towns in different regions of the world.

Characterization of excretory/secretory products of the Taenia crassiceps cysticercus involved in the induction of regulatory T cells in vivo

The ability to modulate the host immune response has allowed some parasites to establish themselves in the tissues of an immunocompetent organism. While some parasite excretion/secretion products (ESPs) were recently reported to induce differentiation of regulatory T cells (Tregs), their identity is not known. This work is aimed to identify and characterize ESPs of Taenia crassiceps cysticerci linked with Treg induction in vivo. ESPs were obtained from cultures of T. crassiceps cysticerci and inoculated in mice, measuring Treg levels by flow cytometry. Proteins in ESPs were analyzed by electrophoresis; then, ESPs were classified as either differential or conserved. Differentially included proteins were MS-sequenced and functionally characterized. Only 4 of 10 ESPs induced Tregs. Proteins with catalytic activity and those involved in immunological processes predominated, supporting the idea that these molecules could play an important role in the induction of Tregs.

First helminthological data on the Iberian adder, Vipera seoanei

The helminth fauna present in the gut contents of Iberian adders, Vipera seoanei (Squamata: Viperidae), were characterised and analysed in respect to biological and eco-geographic factors that may affect the occurrence and diversity of helminths in this species. A total of 317 samples of preserved stomachs and intestines, covering the distributional range of V. seoanei, were examined. Similar to other Vipera species from the Iberian Peninsula, the helminth fauna was also impoverished in V. seoanei, but unlike other Vipera species from Central and East Europe, helminths were mostly found in adult vipers, and occurred in vipers located at the periphery of the species range, characterised by low elevation, high temperature and precipitation levels, and abundant pastures.

Battle of the sexes: analysis of sex bias in host use and reporting practices in parasitological experiments

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.

Malarial and intestinal parasitic co-infections in indigenous populations of the Brazilian Amazon rainforest

The Brazilian Amazon rainforest region has a significant prevalence of malarial and intestinal parasitic infections in indigenous populations, accounting for a disproportionate burden. Thus, a cross-sectional study was conducted to assess the prevalence and association between malarial and intestinal protozoan and helminth infections in four remote indigenous villages in the Brazilian Amazon Forest. A total of 430 individuals participated in the study, and Plasmodium infections were diagnosed by examination of thick blood smears and PCR. Stool samples 295 individuals (69%) were examined by direct smear and the Kato-Katz technique. The overall prevalence of malaria, intestinal protozoan infection, and intestinal helminth infection was 14.2%, 100%, and 39.3%, respectively. Polyparasitism was predominant (83.7%), and most infected individuals had at least two or more different species of intestinal protozoan and/or helminth parasites. The prevalence of co-infection was 49.5%, and in individuals with intestinal protozoa and helminth infections (34%), Entamoeba. coli, Entamoeba histolytica, and Ascaris lumbricoides were the most common parasites. In individuals with malaria and protozoa infections (10.2%), P. vivax, E. coli, and E. histolytica predominated, and in individuals with malaria, protozoa, and helminth infections (5.4%). P. vivax, E. coli, E. histolytica, and A. lumbricoides predominated. Intestinal polyparasitism was common in the study population, and the presence of helminths was associated with an increased number of intestinal parasitic species. However, Plasmodium infections were neither a risk nor a protective factor for helminth infections; the same was true for helminth infections in relation to Plasmodium. The high prevalence of intestinal polyparasitism with Plasmodium co-infections highlights the need for combining strategies that may help control both malaria and intestinal parasite and generate a health approach aligned with indigenous perspectives.

Co-infections of respiratory pathogens and gastrointestinal parasites in smallholder pig production systems in Uganda

A cross-sectional study was conducted to identify factors for infections of pigs with key respiratory pathogens: porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PPRSv), Mycoplasma hyopneumoniae (M. hyo), Actinobacillus pleuropneumoniae (App), and gastrointestinal (GI) parasites in Uganda. A structured questionnaire was used to collect data on management practices associated with infections. Ninety (90) farms and 259 pigs were sampled. Sera were screened against 4 pathogens using commercial ELISA tests. The Baerman's method was used to identify parasite species in faecal samples. Logistic regression was done to identify risk factors for infections. Results showed individual animal seroprevalence of PCV2 was 6.9% (95% CI 3.7-11.1), PRRSv 13.8% (95% CI 8.8-19.6), M. hyo 6.4% (95% CI 3.5-10.5), and App 30.4% (95% CI 24.8-36.5). The prevalence of Ascaris spp. was 12.7% (95% CI 8.6-16.8), Strongyles spp was 16.2% (95% CI 11.7-20.7), and Eimeria spp. was 56.4% (95% CI 50.3-62.4). Pigs infested with Ascaris spp. were more likely to test positive to PCV2, odds ratio (OR) 1.86 (CI 1.31-2.60; p = 0.0002). For M. hyo, infection with Strongyles spp. was a risk factor (OR 12.9, p < 0.001). Pigs that had Strongyles and Ascaris spp. Infections (ORs 3.5 and 3.4, p < 0.001 respectively) were likely to have co-infections. The model showed that use of cement, elevated floor, and limiting contacts with outside pigs were protective while using mud and helminth infestations increased risks of co-infections. This study provided evidence that improved housing and biosecurity are critical in reducing pathogen incidence in herds.

SPATIAL VARIATION IN HELMINTH PARASITE COMMUNITIES OF THE FRENCH GRUNT, HAEMULON FLAVOLINEATUM (TELEOSTEI: HAEMULIDAE), FROM THE YUCATAN PENINSULA

The French grunt, Haemulon flavolineatum, is an abundant fish and a good model for studying parasite communities. Specimens were collected at 4 localities between the Campeche Bank (within the Gulf of Mexico) and the Mexican Caribbean Sea to describe and compare the differences and similarities between localities and regions in the communities of parasitic helminths. Thus, we calculated the Hill numbers associated with species richness (q = 0) and the dominance estimator (q = 2) using rarefaction and extrapolation curves to provide asymptotic estimators of diversity. A 2-way PERMANOVA was used to determine whether there was a significant difference in parasite assemblage structure between localities or regions. A total of 11 helminth taxa (species level) were recorded in 104 individuals of H. flavolineatum, consisting of 8 digenean trematodes species, 2 acanthocephalan species, and 1 nematode species. Our findings include new reports of 7 parasite taxa and new geographical records for some parasites in H. flavolineatum. The highest dissimilarities in parasite composition were observed between the most distant locations (Banco Chinchorro vs. Cayo Arcas) that were each located in different regions. Species richness was similar between regions, although the most dominant helminths were Postmonorchis orthopristis and Dollfustrema sp. in the Mexican Caribbean and Campeche Bank regions, respectively. Future studies should explore how patterns in parasite community structure are affected by currents running south to north by the Yucatan Current through the Yucatan Channel and easterly to Campeche Bank.

Infection patterns of helminth community in black rockcod Notothenia coriiceps in West Antarctica over a 6-year term

Patterns of the rockcod Notothenia coriiceps infection with helminths were analysed to understand the dynamics of parasite communities in this Antarctic fish and to test their stability over time. The study was performed using helminth samples collected from 183 N. coriiceps in 2014-2015 and 2020-2021 in the vicinity of the Ukrainian Antarctic station (UAS) "Akademik Vernadsky", Galindez Island, Argentine Islands, West Antarctica. Overall, 25 helminth taxonomical categories (nine trematodes, four cestodes, five nematodes, and seven acanthocephalans) were subjected to analysis. A direct comparison of the helminth population characteristics showed that nine species significantly changed their infection parameters during the 6 years between the samples. Seven of them (Pseudoterranova sp., Contracaecum sp., Ascarophis nototheniae, monolocular metacestodes, bilocular metacestodes, Metacanthocephalus rennicki, and Diphyllobothrium sp.) were found to have a significant impact on the differences between helminth infracommunities in 2014-2015 and 2020-2021. Most studied patterns of helminth component community appeared to show a stable tendency, and observed fluctuations were close to the steady trend. Slight but significant changes in the infection patterns observed in this study might have been caused by changes in the populations of intermediate, paratenic, and definitive hosts of helminths (marine invertebrates, mammals, and birds), which participate in helminth transmission in Antarctic ecosystems.

Copper chloride and copper sulphate in combination with nitroxynil against gastrointestinal nematodes of ruminants: A possible hitchhiking synergic effect at low concentrations

Infections caused by Haemonchus spp. and Trichostrongylus spp. are major health problems for sheep and cattle. The objective of this study was to determine the efficacy of copper chloride (CuCl₂), and copper sulphate (CuSO₄) at 2.0, 7.0, 30.0, 125.0, 500.0, and 2000.0 µM formulations, and nitroxynil 34% (NTX) at 0.235 mM against gastrointestinal nematodes (GINs) of ruminants. Hence, the in vitro egg hatch test (EHT), the larval development test (LDT), and the larval migration inhibition test (LMIT) were used. Haemonchus spp. (52%) and Trichostrongylus spp. (38%) were the most frequently found parasites. The data fitted a concentration-dependent shape with the highest efficacies of CuCl₂ and CuSO₄ at 95.2 and 97.3% for parasites collected from sheep, and 95.8 and 93.4% from cattle, respectively. The combination of the 50% inhibitory concentration (IC₅₀) of CuCl₂ and CuSO₄ and the IC₁₀ of NTX showed up to a 52% increase in efficacy above the expected additive results, demonstrating a synergic/drug enhancer interaction. NTX may retain Cu-II ions by complexation, in a hitchhiking mechanism carrying the salts across the parasite cell wall, causing oxidative stress as a consequence of free radical production and cell damage. Synergy data between NTX and CuCl₂, and CuSO₄ represent a viable opportunity to develop new formulations for combating parasites of ruminants (i.e., Fasciola hepatica, Haemonchus spp., and Oesophagostomum spp.).

Loeffler's Syndrome and Multifocal Cutaneous Larva Migrans: Case report of an uncommon occurrence and review of the literature

Cutaneous larva migrans (CLM) is a zoonotic skin disease that is frequently diagnosed in tropical and subtropical countries. Loeffler's syndrome (LS) is a transient respiratory ailment characterised by pulmonary infiltration along with peripheral eosinophilia and commonly follows parasitic infestation. We report a 33-year-old male patient who presented to a tertiary care hospital in eastern India in 2019 with LS that was attributed secondary to multifocal CLM. Treatment with seven-day course of oral albendazole (400 mg daily) coupled with nebulisation (levosalbutamol and budesonide) led to complete resolution of cutaneous lesions and respiratory complaints within two weeks. There was complete resolution of pulmonary pathology at four-weeks follow-up.

Long-term study reveals central European aerial insectivores as an unusual group of hosts that harbor mostly helminths that are unable to complete life-cycles in the nesting quarters of their hosts

BACKGROUND

Central European aerial insectivores are long-distance migrants that winter in sub-Saharan Africa. Most of them employ the fly-and-forage migrating strategy and differ in their food composition. The composition and structure of helminth component communities of these hosts are poorly understood, and information regarding seasonality and long-term changes is unavailable.

METHODS

From 1963 to 2022, we analyzed the population trends of helminths in five aerial insectivore species. Namely, we examined Apus apus, Hirundo rustica, Delichon urbicum, Riparia riparia, and Ficedula albicollis; all originated from the Czech Republic.

RESULTS

We identified central European aerial insectivores as hosts that are parasitized mostly by helminths that cannot complete their life-cycles in the nesting quarters of their hosts. This phenomenon is unknown in other bird host species. In contrast, only a single dominant trematode species that completes its life-cycle locally colonized the central European aerial insectivores. All other dominant species of Trematoda, all Nematoda, and all Acanthocephala were dependent on intermediate hosts unavailable in the nesting quarters of the examined bird hosts. Surprisingly, these helminths transmitted from winter quarters or migratory routes were diverse, and many of them were abundant in terms of both prevalence and intensity of infection. The helminth component communities of aerial insectivores were dynamic systems. During the study period, three species became new and regularly encountered members of helminth fauna of examined hosts, and other species gradually increased or decreased their intensity of infection. In contrast to other groups of bird hosts, the dominant helminth species of aerial insectivores did not experience local extinctions or rapid population losses.

CONCLUSIONS

The analysis of helminths of five central European aerial insectivores revealed component communities that heavily rely on completing host-parasite cycles at migration routes or wintering grounds. The composition of the analyzed component communities changed dynamically during the 60-year-long study period, but there was no evidence of large-scale declines in abundance or prevalence.

Checklist of parasites associated with 'reptiles' in Northeast Brazil

Reptiles, as well as other vertebrate groups, harbour a significant diversity of parasitic organisms, from nematodes and other helminths to viruses and bacteria. The Northeast is one of the richest regions in Brazil in terms of the reptile diversity, number of species and endemism. Parasites are diverse organisms and knowledge about the parasitic fauna of vertebrates is an important factor in understanding the ecological relationships between hosts and the environment. Studies on the parasitic fauna of reptiles in South America have increased in the past few years. The present review is a compilation of 122 studies published from 1924 to 2021. We present information on 101 species of reptiles from five groups (amphisbaenians, crocodile, testudines, snakes and lizards) and 183 parasitic taxa belonging to four phyla: Nematoda; Arthropoda; Platyhelminthes; and Acanthocephala. Nematodes were the most frequently recorded species. Lizards and snakes had more records of parasitism and higher levels of parasite richness and diversity. Ceará was the state with most studies and recorded cases of parasite-host association. The Caatinga and Atlantic Forest were the most investigated environments. The objective of this review was to contribute knowledge on the parasitic biodiversity in reptiles from Northeast Brazil, which may help identify gaps in our knowledge and guide future studies.

Synthesis and Clinical Examination of Novel Formulations of Ivermectin, Albendazole and Niclosamide for the Treatment of Equine Gastrointestinal Helminthoses

Background

This study aimed to develop new complex preparations of ivermectin, niclosamide and albendazole based on solid-phase mechanochemical technology, and to evaluate their efficacy against equine nematodosis and cestodosis.

Methods

Novel formulation of antiparasitic paste were prepared using joint mechano-chemical treatment of ivermectin (0.2 mg/kg bodyweight; BW), niclosamide (10 mg/kg BW) and albendazole (3, 5, 10 mg/kg BW) substances with polyvinylpyrrolidone and arabinogalactan. For the evaluation of activity of different doses of formulations against gastrointestinal tract helminths a total of 151 adult horses of the Novoaltai breed weighing 450-500 kg naturally infected with strongyles (>150 egg per gram of faeces, EPG), Parascaris spp. (>20 EPG) and Anoplocephala spp. (>10 EPG) were selected. Antiparasitic pastes were orally fed to the horses and faecal egg count reduction counts were compared prior to and 14 days after the treatment.

Results

Pastes with mechanically modified ivermectin showed 91.4-100% efficacy against strongyles and Parascaris. Pastes with modified albendazole and niclosamide were also effective against Anoplocephala in all tested dosages i.e. 78.6-100%. In particular, treatment with two formulations containing i) 0.2 mg ivermectin, 10 mg albendazole, 10 mg niclosamide, and ii) 0.2 mg ivermectin, 3 mg albendazole showed 100% efficacy against strongyles, Parascaris and Anoplocephala.

Conclusion

Solid-phase mechanochemical technology could be applied in equine anthelminthics production. It is suggested that future studies focus on plasma concentration-time profile of these highly effective pastes.

Evaluation of a commercial coproantigen immunoassay for the detection of Toxocara cati and Ancylostoma tubaeforme in cats and Uncinaria stenocephala in dogs

Coproantigen immunoassays (IDEXX Fecal Dx® antigen tests) were evaluated for their ability to identify Toxocara cati and Ancylostoma tubaeforme infections in cats and Uncinaria stenocephala infection in dogs. Five cats were experimentally infected with 500 embryonated eggs of T. cati, eight cats with 500 third-stage larvae (L3) of A. tubaeforme and seven dogs with 500 L3 of U. stenocephala. In addition to the three coproantigen tests, the course of infection was monitored by a combined sedimentation-flotation method with ZnSO₄ as flotation medium (specific gravity: 1.28-1.30) and a modified McMaster method in case of copromicroscopically positive samples. Eggs of T. cati were first observed between 28 and 54 days post infection (dpi) in four of the five infected cats. In these four cats, positive roundworm coproantigen signals were obtained between 16 and 44 dpi. Positive coproantigen signal always preceded egg observations, but the interval varied between 6 and 30 days. Hookworm-specific positive coproantigen signals were detected in seven of the eight A. tubaeforme infected cats between 10 and 52 dpi, while consecutive egg excretion was observed in three cats between day 26 and 54 pi. Of these three, coproantigen signal preceded egg observation by 12 to 24 days. Four cats had positive coproantigen results in the absence of egg excretion, and one cat never achieved a positive result for egg or coproantigen. In six of seven U. stenocephala infected dogs, infection was confirmed by copromicroscopy between 16 and 24 dpi as well as for hookworm coproantigen between 10 and 14 dpi. Coproantigen signal was detected prior to egg observation by 2 to 14 days. No cross-reactions between the roundworm, hookworm und whipworm tests occurred in study animals. The results of this study demonstrate the ability of the coproantigen tests to detect the common roundworm and hookworm infections in cats and U. stenocephala infections in dogs as well as the ability to detect the prepatent stage of infection.