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The ongoing increase in wild boar populations across Europe has fostered human-wildlife conflicts, including the transmission of emerging pathogens with zoonotic importance. Blastocystis is a ubiquitous, faecal-oral transmitted protist that can cause gastrointestinal illnesses and is observed in humans and animals worldwide. The role of wildlife in the epidemiology of Blastocystis is insufficiently understood. Thus, we investigated the occurrence and subtype diversity of Blastocystis in free-ranging wild boars from the Iberian Peninsula using conventional PCR and next-generation amplicon sequencing of a fragment of the ssu RNA gene. A total of 459 wild boar faecal samples were collected across Spain (n = 360) and Portugal (n = 99) between 2014 and 2021. Blastocystis was present in 15.3% (70/459; 95% CI 12.1-18.9) of the wild boars analysed, and its occurrence was significantly higher in Portugal (34.3%, 34/99; 95% CI 25.1-44.6) than in Spain (10.0%, 36/360; 95% CI 7.1-13.6). Seven Blastocystis subtypes (ST5, ST10b, ST13-ST15, ST24b, and ST43) were detected among the surveyed wild boar populations, with greater variability detected in Portuguese samples. ST5 was identified in all the Blastocystis-positive animals, whereas 14.3% of them harboured ST mixed colonisations. Our results demonstrate that Blastocystis ST5 is particularly adapted to infect wild boars. The additional identification of zoonotic STs reinforces the role of wild boars as spreaders of zoonotic infections with public health significance., (© 2024. The Author(s).)

Ascaris is one of the most widespread helminth infections, leading to chronic morbidity in humans and considerable economic losses in pig farming. In addition, pigs are an important reservoir for the zoonotic salmonellosis , where pigs can serve as asymptomatic carriers. Here, we investigated the impact of an ongoing Ascaris infection on the immune response to Salmonella in pigs. We observed higher bacterial burdens in experimentally coinfected pigs compared to pigs infected with Salmonella alone. The impaired control of Salmonella in the coinfected pigs was associated with repressed interferon gamma responses in the small intestine and with the alternative activation of gut macrophages evident in elevated CD206 expression. Ascaris single and coinfection were associated with a rise of CD4 - CD8α + FoxP3 + Treg in the lymph nodes draining the small intestine and liver. In addition, macrophages from coinfected pigs showed enhanced susceptibility to Salmonella infection in vitro and the Salmonella- induced monocytosis and tumor necrosis factor alpha production by myeloid cells was repressed in pigs coinfected with Ascaris . Hence, our data indicate that acute Ascaris infection modulates different immune effector functions with important consequences for the control of tissue-invasive coinfecting pathogens.IMPORTANCEIn experimentally infected pigs, we show that an ongoing infection with the parasitic worm Ascaris suum modulates host immunity, and coinfected pigs have higher Salmonella burdens compared to pigs infected with Salmonella alone. Both infections are widespread in pig production and the prevalence of Salmonella is high in endemic regions of human Ascariasis, indicating that this is a clinically meaningful coinfection. We observed the type 2/regulatory immune response to be induced during an Ascaris infection correlates with increased susceptibility of pigs to the concurrent bacterial infection., Competing Interests: The authors declare no conflict of interest.

Trichinellosis is a zoonotic disease that has been studied mainly in domestic pigs (Sus scrofa domesticus). The cycle involves infection in domestic and wild fauna, which fulfill complex ecological roles, where Trichinella spiralis is reported in wild boar (Sus scrofa). The objective of this study was to determine the prevalence of trichinellosis in wild boar and evaluate the distance of positive animals to the nearest urbanization areas in Argentina Patagonia. Necropsies were carried out on wild boar hunted in the Nahuel Huapi and Lanín National Parks and surrounding areas. Skeletal muscle samples were collected from 1,694 wild boar and artificial digestion was performed on all samples. Trichinella spp. were found in 96 (5.8%) wild boar (0.2 to 424 Larvae/g). Parasitism in wild boar depends on the distribution of the population in natural and urban areas. Infected wild boar were found near peri-urban areas, demonstrating the importance of routine epidemiological surveillance and sanitary measures in and around cities. More research is needed to identify the Trichinella species that infect wild animals. We recommend the application of active and passive epidemiological surveillance in South America on exotic and native fauna that are hunted and consumed by humans.

Background: Geographically targeted Taenia solium ring approaches consisting of treating individuals within a radius of 100-meter of a cysticercosis positive pig have been trialled in Peru. This study explored if a similar approach could be proposed to control T. solium transmission in a post elimination setting in Zambia, focussing on community members' willingness to be sampled and treated., Methodology and Principal Findings: The study was conducted in a community where elimination of active T. solium transmission was achieved. All eligible pigs and people were sampled, at 4- to 6-monthly intervals, followed by implementation of the ring treatment approach. This implied that whenever a pig was seropositive for cysticercosis during sampling, every human and pig residing in a radius of 50-meters of the seropositive pig would be treated. The results of the positive human stool samples were used to create the rings, whenever no pigs were positive. From June 2018 to October 2019, four samplings, followed by ring treatments were conducted. Between 84% and 91% of the willing people provided a stool sample, covering 46% to 59% of the total population living in the study area. Between 78% and 100% of the eligible pigs got sampled. Three ring treatments were based on porcine seropositivity and one on taeniosis results. Two to four rings were opened per sampling. During the ring treatments, between 89% and 100% of the eligible human and pig population living within a ring was treated., Conclusions: Participants were willing to participate and get treatment, once the rings were opened. However, the utility of ring treatment approaches in a post elimination setting needs further evaluation, given the lack of highly accurate diagnostic tools for porcine cysticercosis and the challenges in obtaining stool samples. The ring treatment approach adopted should be further improved before recommendations to public health authorities can be given., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Trevisan et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Toxoplasma gondii, a common protozoan parasite, poses significant public health risks due to its potential to cause toxoplasmosis in humans and can be contracted from pigs, which are considered its critical intermediate host. The aim of this study is to evaluate the prevalence of T. gondii in slaughtered pigs for human consumption, emphasizing the zoonotic implications and the need for improved biosecurity and monitoring practices in pig farming. A total of 1,526 pig samples (1,051 whole blood samples and 384 lung tissue samples from the local slaughterhouse and 91 aborted fetus samples from local farms) were collected throughout the whole country of Korea in 2020. Among them, 6 (0.4%) were found to be infected with T. gondii by nested PCR. When compared by sample type, the prevalence of T. gondii was significantly higher in the aborted fetus samples (2.2%, 2/91) than in the blood (0.3%, 3/1,051) and lung tissue samples (0.3%, 1/384). The B1 gene sequence of T. gondii was similar (97.9-99.8%) to that of the other T. gondii isolates. This study represents the first molecular genotyping survey of T. gondii in the lung tissue of fattening pigs and aborted fetuses in Korea. Our findings indicated the importance of adopting preventive measures including the implementation of rigorous farm hygiene protocols and the promotion of public awareness about the risks of consuming undercooked pork. By addressing the gaps in current control strategies and encouraging the One Health approach, this study contributes to the development of more effective strategies to mitigate the transmission of T. gondii from pigs to humans, ultimately safeguarding public health.

Cryptosporidiosis is an infectious enteric disease caused by species (some of them zoonotic) of the genus Cryptosporidium that in many countries are under surveillance. Typing assays critical to the surveillance of cryptosporidiosis typically involve characterization of Cryptosporidium glycoprotein 60 genes (gp60). Here, we characterized the gp60 of Cryptosporidium suis from two samples-a human and a porcine faecal sample-based on which a preliminary typing scheme was developed. A conspicuous feature of the C. suis gp60 was a novel type of tandem repeats located in the 5' end of the gene and that took up 777/1635 bp (48%) of the gene. The C. suis gp60 lacked the classical poly-serine repeats (TCA/TCG/TCT), which is usually subject to major genetic variation, and the length of the tandem repeat made a typing assay incorporating this region based on Sanger sequencing practically unfeasible. We therefore designed a typing assay based on the post-repeat region only and applied it to C. suis-positive samples from suid hosts from Norway, Denmark, and Spain. We were able to distinguish three different subtypes; XXVa-1, XXVa-2, and XXVa-3. Subtype XXVa-1 had a wider geographic distribution than the other subtypes and was also observed in the human sample. We think that the present data will inform future strategies to develop a C. suis typing assay that could be even more informative by including a greater part of the gene, including the tandem repeat region, e.g., by the use of long-read next-generation sequencing., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Sarcocystis miescheriana infection is an important cause of carcass condemnation during meat inspection. The infection can cause morbidity and mortality in domestic pigs. In this study, an 8-month-old finisher pig was presented to a local abattoir for slaughter. Multiple white nodular lesions affecting the meat were observed, resulting in the condemnation of the carcass. Consequently, half of the carcass was submitted to the necropsy diagnostic laboratory in the School of Veterinary Medicine for further evaluation. Grossly, all superficial and deep muscle groups had severe multifocal macrocysts (3 mm × 2 mm × 1 mm) on the surface and extending deep into the skeletal musculature. Histopathology revealed moderate multifocal granulomatous and eosinophilic myositis with intralesional degenerated and intact parasites. Sample genomic DNA sequence analysis of the 18S RNA gene showed 100% identity to S. miescheriana in the GenBank. This is the first report of S. miescheriana in Grenada, West Indies., (© 2024 The Author(s). Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Background: Parasitic diseases of pigs are a public and veterinary health problem. Helminths influence pork production, whereas backyard pigs can transmit these parasites., Objectives: This work aimed to investigate the prevalence of antibodies against Ascaris suum and Trichinella spiralis in backyard pigs from Jamiltepec, Region de la Costa, Oaxaca, in Southwestern Mexico., Methods: Six hundred sixty-four serum samples were obtained from backyard pigs from 23 rural villages distributed in 5 municipalities; samples were taken in a non-probabilistic manner with the owner's consent. The presence of serum antibodies against a total extract of A. suum adult worm was determined by ELISA. In contrast, antibodies to the excretion-secretion products of the T. spiralis muscle larva were determined by Western blot., Results: The global seroprevalence for A. suum was 5.12% and 2.41% for T. spiralis; however, antibodies were only found in 8 villages and distributed in 3 municipalities. The highest frequency of positivity for Ascaris was found in the municipality of Santa Catarina Mechoacán (13.01%), whereas, in Santa María Huazalotitlán, the highest frequency of positivity for Trichinella was found (5.75%). In San Andrés, frequencies were 7.23% and 4.82%, respectively. No statistical differences were observed between populations., Conclusions: Our data suggest that helminth transmission is restricted by locality. However, further studies must be conducted to understand the factors limiting this transmission to promote pork meat production in parasite-free zones., (© 2024 The Author(s). Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Natural killer (NK) cells play a key role in defense against Salmonella infections during the early phase of infection. Our previous work showed that the excretory/secretory products of Ascaris suum repressed NK activity in vitro. Here, we asked if NK cell functionality was influenced in domestic pigs during coinfection with Ascaris and Salmonella enterica serotype Typhimurium. Ascaris coinfection completely abolished the IL-12 and IL-18 driven elevation of IFN-γ production seen in CD16 + CD8α + perforin + NK cells of Salmonella single-infected pigs. Furthermore, Ascaris coinfection prohibited the Salmonella-driven rise in NK perforin levels and CD107a surface expression. In line with impaired effector functions, NK cells from Ascaris-single and coinfected pigs displayed elevated expression of the inhibitory KLRA1 and NKG2A receptors genes, contrasting with the higher expression of the activating NKp46 and NKp30 receptors in NK cells during Salmonella single infection. These differences were accompanied by the highly significant upregulation of T-bet protein expression in NK cells from Ascaris-single and Ascaris/Salmonella coinfected pigs. Together, our data strongly indicate a profound repression of NK functionality by an Ascaris infection which may hinder infected individuals from adequately responding to a concurrent bacterial infection., (© 2024. The Author(s).)

Background: The giant roundworm Ascaris is an intestinal nematode, causing ascariasis by infecting humans and pigs worldwide. Recent estimates suggest that Ascaris infects over half a billion people, with chronic infections leading to reduced growth and cognitive ability. Ascariasis affects innumerable pigs worldwide and is known to reduce production yields via decreased growth and condemnation of livers. The predominant anthelminthic drugs used to treat ascariasis are the benzimidazoles. Benzimidazoles interact with β-tubulins and block their function, and several benzimidazole resistance-associated mutations have been described in the β-tubulins of ruminant nematodes. Recent research on ascarids has shown that these canonical benzimidazole resistance-associated mutations are likely not present in the β-tubulins of Ascaris, Ascaridia or Parascaris, even in phenotypically resistant populations., Methods: To further determine the putative absence of key β-tubulin polymorphisms, we screened two β-tubulin isotypes of Ascaris, highly expressed in adult worms. Using adult and egg samples of Ascaris obtained from pigs and humans worldwide, we performed deep amplicon sequencing to look for canonical resistance-associated mutations in Ascaris β-tubulins. Subsequently, we examined these data in closer detail to study the population dynamics of Ascaris and genetic diversity within the two isotypes and tested whether genotypes appeared to partition across human and pig hosts., Results: In the 187 isolates, 69 genotypes were found, made up of eight haplotypes of β-tubulin isotype A and 20 haplotypes of isotype B. Single nucleotide polymorphisms were seen at 14 and 37 positions for β-tubulin isotype A and isotype B, respectively. No evidence of any canonical benzimidazole resistance-associated mutations was found in either human- or pig-derived Ascaris isolates. There was, however, a difference in the genetic diversity of each isotype and distribution of β-tubulin genotypes between human- and pig-derived Ascaris. Statistical tests of population differentiation show significant differences (p < 0.001) between pig- and human-derived worms; however, more diversity was seen between worms from different populations than worms from different hosts., Conclusions: Our work suggests an absence of canonical β-tubulin mutations within Ascaris, but alternative modes of anthelminthic resistance may emerge necessitating continued genetic scrutiny alongside monitoring of drug efficacy., (© 2024. The Author(s).)

Ascaris spp. undergo extensive migration within the body before establishing patent infections in the small intestinal tract of humans and pigs. However, whether larval migration is critical for inducing efficient type 2 responses remains poorly understood. Therefore, we investigated systemic versus local adaptive immune responses along the hepato-tracheal migration of Ascaris suum during primary, single infections in conventionally raised pigs. Neither the initial invasion of gut tissue nor migration through the liver resulted in discernable Th2 cell responses. In contrast, lung-stage larvae elicited a Th2-biased pulmonary response, which declined after the larvae had left the lungs. In the small intestine, we observed an accumulation of Th2 cells upon the arrival of fourth-stage larvae (L4) to the small intestinal lumen. In parallel, we noticed robust and increasing Th1 responses in circulation, migration-affected organs, and draining lymph nodes. Phenotypic analysis of CD4+ T cells specifically recognizing A. suum antigens in the circulation and lung tissue of infected pigs confirmed that the majority of Ascaris -specific T cells produced IL-4 (Th2) and, to a much lesser extent, IL-4/IFN-g (Th2/1 hybrids) or IFN-g alone (Th1). These data demonstrate that lung-stage but not the early liver-stage larvae lead to a locally restricted Th2 response. Significant Th2 cell accumulation in the small intestine occurs only when L4 complete the body migration. In addition, Th2 immunity seems to be hampered by the concurrent, nonspecific Th1 bias in growing pigs. Together, the late onset of Th2 immunity at the site of infection and the Th1-biased systemic immunity likely enable the establishment of intestinal infections by sufficiently large L4 stages and pre-adult worms, some of which resist expulsion mechanisms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Oser, Midha, Schlosser-Brandenburg, Rausch, Mugo, Kundik, Elizalde-Velázquez, Adjah, Musimbi, Klopfleisch, Helm, von Samson-Himmelstjerna, Hartmann and Ebner.)

Background: Porcine cysticercosis, a serious zoonotic parasitic disease, is caused by the larvae of Taenia solium and has been acknowledged by the World Organization for Animal Health. The current detection methods of Cysticercus cellulosae cannot meet the needs of large-scale and rapid detection in the field. We hypothesized that the immunofluorescence chromatography test strip (ICS) for detecting Cysticercus cellulosae, according to optimization of a series of reaction systems was conducted, and sensitivity, specificity, and stability testing, and was finally compared with ELISA. This method utilizes Eu 3+ -labeled time-resolved fluorescent microspheres (TRFM) coupled with TSOL18 antigen to detect TSOL18 antibodies in infected pig sera., Results: ICS and autopsy have highly consistent diagnostic results (n = 133), as determined by Cohen's κ analysis (κ = 0.925). And the results showed that the proposed ICS are high sensitivity (0.9459) with specificity (0.9792). The ICS was unable to detect positive samples of other parasites. It can be stored for at least six months at 4℃., Conclusions: In summary, we established a TRFM-ICS method with higher sensitivity and specificity than indirect ELISA. Results obtained from serum samples can be read within 10 min, indicating a rapid, user-friendly test suitable for large-scale field detection., (© 2024. The Author(s).)

The clinical consequences of toxoplasmosis are greatly dependent on the Toxoplasma gondii strain causing the infection. To better understand its epidemiology and design appropriate control strategies, it is important to determine the strain present in infected animals. Serotyping methods are based on the detection of antibodies that react against segments of antigenic proteins presenting strain-specific polymorphic variations, offering a cost-effective, sensitive, and non-invasive alternative to genotyping techniques. Herein, we evaluated the applicability of a panel of peptides previously characterized in mice and humans to serotype sheep and pigs. To this end, we used 51 serum samples from experimentally infected ewes (32 type II and 19 type III), 20 sheep samples from naturally infected sheep where the causative strain was genotyped (18 type II and 2 type III), and 40 serum samples from experimentally infected pigs (22 type II and 18 type III). Our ELISA test results showed that a combination of GRA peptide homologous pairs can discriminate infections caused by type II and III strains of T. gondii in sheep and pigs. Namely, the GRA3-I/III-43 vs . GRA3-II-43, GRA6-I/III-213 vs. GRA6-II-214 and GRA6-III-44 vs. GRA6-II-44 ratios showed a statistically significant predominance of the respective strain-type peptide in sheep, while in pigs, in addition to these three peptide pairs, GRA7-II-224 vs. GRA7-III-224 also showed promising results. Notably, the GRA6-44 pair, which was previously deemed inefficient in mice and humans, showed a high prediction capacity, especially in sheep. By contrast, GRA5-38 peptides failed to correctly predict the strain type in most sheep and pig samples, underpinning the notion that individual standardization is needed for each animal species. Finally, we recommend analyzing for each animal at least 2 samples taken at different time points to confirm the obtained results., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Arranz-Solís, Tana, Tejerina-de-Uribe, López-Ureña, Koudela, Francia, Ortega-Mora and Álvarez-García.)

Background: Ethno-veterinary practices could be used as a sustainable developmental tool by integrating traditional phytotherapy and husbandry. Phytotherapeutics are available and used worldwide. However, evidence of their antiparasitic efficacy is currently very limited. Parasitic diseases have a considerable effect on pig production, causing economic losses due to high morbidity and mortality. In this respect, especially smallholders and organic producers face severe challenges. Parasites, as disease causing agents, often outcompete other pathogens in such extensive production systems. A total of 720 faecal samples were collected in two farms from three age categories, i.e. weaners, fatteners, and sows. Flotation (Willis and McMaster method), modified Ziehl-Neelsen stained faecal smear, centrifugal sedimentation, modified Blagg technique, and faecal cultures were used to identify parasites and quantify the parasitic load., Results: The examination confirmed the presence of infections with Eimeria spp., Cryptosporidium spp., Balantioides coli (syn. Balantidium coli), Ascaris suum, Oesophagostomum spp., Strongyloides ransomi, and Trichuris suis, distributed based on age category. A dose of 180 mg/kg bw/day of Allium sativum L. and 90 mg/kg bw/day of Artemisia absinthium L. powders, administered for 10 consecutive days, revealed a strong, taxonomy-based antiprotozoal and anthelmintic activity., Conclusions: The results highlighted the therapeutic potential of both A. sativum and A. absinthium against gastrointestinal parasites in pigs. Their therapeutic effectiveness may be attributed to the content in polyphenols, tocopherols, flavonoids, sterols, sesquiterpene lactones, and sulfoxide. Further research is required to establish the minimal effective dose of both plants against digestive parasites in pigs., (© 2024. The Author(s).)

Toxoplasma gondii and Trichinella spp. are critical tissue-dwelling foodborne zoonotic parasites associated with pork consumption and pig rearing. Despite being a major pig-rearing region in the country, Northeastern India has not undergone any investigation regarding the presence of T. gondii and Trichinella spp. in pigs. Therefore, this study aims to determine the seroprevalence of T. gondii and Trichinella spp. and identify associated risk factors in pigs reared by tribal communities and small-holder livestock farmers in the northeastern region of India. In a cross-sectional serological survey, 400 pigs from 400 households across five northeastern states of India underwent testing for the seroprevalence of porcine toxoplasmosis and trichinellosis. Serum samples (80 from each state) were analyzed using commercially available ELISA assays. Data on backyard farm characteristics and various management aspects were collected, and risk factors linked with prevalence were analyzed through univariate and multivariate logistic regression analysis. The findings revealed that the apparent and true prevalence of anti-T. gondii antibodies were 45% (40.12-49.88, 95% CI) and 45.7% (40.7-50.69, 95% CI), respectively. As for anti- Trichinella antibodies, both the apparent and true prevalence were 0.75% (-0.1-1.6, 95% CI). The univariate and multivariate analyses indicated that age above 24 months (OR 7.20, 95% CI 2.45-23.71), exposure to cats (OR = 5.87, 95% CI 2.55-14.05), and farms operating for breeding purposes (OR = 5.60, 95% CI 3.01-11.04) were significant risk factors associated with the seroprevalence of T. gondii. This study marks the initial documentation of the seroprevalence of T. gondii and Trichinella spp. in pigs reared by tribal communities in Northeastern India. The results emphasize the significance of these parasites as foodborne zoonotic threats in the region, potentially posing substantial public health risks, especially within tribal and rural communities. The insights derived from this research could be valuable in formulating targeted preventive and control strategies against T. gondii and Trichinella spp. in pigs, not only in this region but also in areas with similar rearing practices., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Milton et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Ascariasis (roundworm) is the most common parasitic helminth infection globally and can lead to significant morbidity in children including chronic lung disease. Children become infected with Ascaris spp. via oral ingestion of eggs. It has long been assumed that Ascaris egg hatching and larval translocation across the gastrointestinal mucosa to initiate infection occurs in the small intestine. Here, we show that A. suum larvae hatched in the host stomach in a murine model. Larvae utilize acidic mammalian chitinase (AMCase; acid chitinase; Chia) from chief cells and acid pumped by parietal cells to emerge from eggs on the surface of gastric epithelium. Furthermore, antagonizing AMCase and gastric acid in the stomach decreases parasitic burden in the liver and lungs and attenuates lung disease. Given Ascaris eggs are chitin-coated, the gastric corpus would logically be the most likely organ for egg hatching, though this is the first study directly evincing the essential role of the host gastric corpus microenvironment. These findings point towards potential novel mechanisms for therapeutic targets to prevent ascariasis and identify a new biomedical significance of AMCase in mammals., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Wild boars (Sus scrofa) may cause substantial damage to crops and can spread zoonotic parasites to domestic animals, posing a risk to health and animal production. Metastrongylus spp. can negatively affect the wild boar population, increasing piglet mortality. In addition to that, studies with Metastrongylus genetic characterization are still scarce in Brazil. The present study aims to characterize Metastrongylus spp. from wild boars hunted in the states of São Paulo, Paraná, and Rio Grande do Sul, Brazil, using traditional morphological description and DNA sequences in an integrative taxonomic approach., Methods: After nematode collection from 58 wild boars, the parasites were morphologically identified and genetically characterized by the amplification of 18S ribosomal DNA (rDNA), 28S rDNA, internal transcribed spacer (ITS) region, and cox-1 mitochondrial DNA (mtDNA). Descriptors of infection were determined and Pearson's Chi-square test was applied to compare the prevalence of infections among the identified parasite species, host age group (juveniles and adults), and sex. The Mann-Whitney U test was performed to compare the mean intensity between the age groups and sex., Results: Metastrongylus salmi, Metastrongylus apri, and Metastrongylus pudendotectus were identified in 77.6% (45/58) of the necropsied wild boars. Metastrongylus salmi was the most prevalent and abundant species (70.7%, 11.1), followed by M. pudendotectus (18.9%, 4.3) and M. apri (17.2%, 2.2). Metastrongylus pudendotectus showed the highest mean intensity and range (25.2, 1-93), followed by M. salmi (15.7, 1-58) and M. apri (12.6, 3-27). We found a significantly higher prevalence of Metastrongylus spp. and M. salmi in adult wild boars, probably associated with a more prolonged time of exposure to intermediate host species. The phylogenetic analysis revealed that ITS2 region and cox-1 mtDNA are the most suitable genetic markers for Metastrongylus species characterization. Genetic variability between M. apri and M. salmi isolates was verified., Conclusions: We expand the knowledge about the Metastrongylus community in the non-captive wild boar population from Brazil as well as the importance of this exotic species in the maintenance of Metastrongylus spp. in its areas of occurrence. The novel genetic sequences obtained may help further studies to understand the genetic diversity in other nematode populations from Brazil and other countries., (© 2023. The Author(s).)

A serologic and epidemiologic study was carried out in order to determinate herd and animal seroprevalence and associated factors for Toxoplasma gondii in commercial pigs from Espírito Santo state, Brazil. Blood samples were collected from 416 pigs from 55 producer farms in 27 municipalities. An indirect immunofluorescent assay (IFA) was performed to estimate the seroprevalence of T. gondii and identify the associated risk factors using a questionnaire. The T. gondii antibody prevalence rate in commercial swine herds was 15.4% (64/416) using a cutoff of 1:64. The seropositivity for T. gondii was related to the presence of cats, water origin and age of swine in the increase of seroprevalence, and the existence of internal isolation fences and use of composting chambers as protective factors. To the best of our knowledge, this is the first study to report anti- T. gondii antibodies in the serum of pigs in the state of Espírito Santo, Brazil. This finding is important to public health because seropositive pigs can harbor tissue cysts in their meat, thereby representing a zoonotic risk for consumers of raw or undercooked porcine meat or its products.

Background: Models can be used to study and predict the impact of interventions aimed at controlling the spread of infectious agents, such as Taenia solium, a zoonotic parasite whose larval stage causes epilepsy and economic loss in many rural areas of the developing nations. To enhance the credibility of model estimates, calibration against observed data is necessary. However, this process may lead to a paradoxical dependence of model parameters on location-specific data, thus limiting the model's geographic transferability., Methods: In this study, we adopted a non-local model calibration approach to assess whether it can improve the spatial transferability of CystiAgent, our agent-based model of local-scale T. solium transmission. The calibration dataset for CystiAgent consisted of cross-sectional data on human taeniasis, pig cysticercosis and pig serology collected in eight villages in Northwest Peru. After calibration, the model was transferred to a second group of 21 destination villages in the same area without recalibrating its parameters. Model outputs were compared to pig serology data collected over a period of 2 years in the destination villages during a trial of T. solium control interventions, based on mass and spatially targeted human and pig treatments., Results: Considering the uncertainties associated with empirical data, the model produced simulated pre-intervention pig seroprevalences that were successfully validated against data collected in 81% of destination villages. Furthermore, the model outputs were able to reproduce validated pig seroincidence values in 76% of destination villages when compared to the data obtained after the interventions. The results demonstrate that the CystiAgent model, when calibrated using a non-local approach, can be successfully transferred without requiring additional calibration., Conclusions: This feature allows the model to simulate both baseline pre-intervention transmission conditions and the outcomes of control interventions across villages that form geographically homogeneous regions, providing a basis for developing large-scale models representing T. solium transmission at a regional level., (© 2023. The Author(s).)

Background: Several studies have reported the roles of Trichinella spiralis extracellular vesicles in immune regulation and pathogen diagnosis. Currently, the T. spiralis muscle larvae excretory/secretory product (Ts-ML-ES) is the antigen recommended by the International Commission on Trichinellosis (ICT) for serological diagnosis of trichinellosis. However, it can only be used to detect middle and late stages of infections, and cross-reactions with other parasite detections occur. Therefore, there is a need to identify antigens for specific detection of early stage trichinellosis., Methods: Extracellular vesicles of T. spiralis muscle larvae (Ts-ML-EVs) were isolated by ultracentrifugation and characterized by transmission electron microscopy, nanoparticle tracking analysis, flow cytometry and western blot. Ts-ML-EVs protein profiles were analyzed by LC-MS/MS proteomics for identification of potential antigens (Ts-TTPA). Ts-TTPA were cloned into pMAL-c5X vector and expressed as recombinant proteins for evaluation of potential as detected antigens by western blot and ELISA., Results: Isolated Ts-ML-EVs were round or elliptic (with diameters between 110.1 and 307.6 nm), showing a bilayer membrane structure. The specific surface markers on the Ts-ML-EVs were CD81, CD63, enolase and the 14-3-3 protein. A total of 53 proteins were identified by LC-MS/MS, including a variety of molecules that have been reported as potential detection and vaccine candidates. The cDNA of Ts-TTPA selected in this study has a total length of 1152 bp, encoding 384 amino acids with a molecular weight of 44.19 kDa. It contains a trypsin domain and can be recognized by anti-His antibody. It reacted with swine sera infected with 10,000 T. spiralis at 15, 25, 35 and 60 days post-infection (dpi). At 10 μg/ml, this antigen could detect T. spiralis antibodies from the swine sera at 13 dpi. There were no cross-reactions with the swine sera infected with other parasites including Clonorchis sinensis, Toxoplasma gondii, Taenia suis, Ascaris suis and Trichuris suis., Conclusions: This study identifies potential early stage detection antigens and more thoroughly characterizes a serine protease domain-containing protein. Extracellular vesicle proteins may be explored as effective antigens for the early stage detection of trichinellosis., (© 2023. The Author(s).)

Background: Toxoplasmosis is a zoonosis with a worldwide presence that is caused by the intracellular parasite Toxoplasma gondii. Active regulation of apoptosis is an important immune mechanism by which host cells resist the growth of T. gondii or avoid excessive pathological damage induced by this parasite. Previous studies found that upregulated expression of microRNA-185 (miR-185) during T. gondii infection has a potential role in regulating the expression of the ARAF gene, which is reported to be associated with cell proliferation and apoptosis., Methods: The expression levels of miR-185 and the ARAF gene were evaluated by qPCR and Western blot, respectively, in mice tissues, porcine kidney epithelial cells (PK-15) and porcine alveolar macrophages (3D4/21) following infection with the T. gondii ToxoDB#9 and RH strains. The dual luciferase reporter assay was then used to verify the relationship between miR-185 and ARAF targets in PK-15 cells. PK-15 and 3D4/21 cell lines with stable knockout of the ARAF gene were established by CRISPR, and then the apoptosis rates of the cells following T. gondii infection were detected using cell flow cytometry assays. Simultaneously, the activities of cleaved caspase-3, as a key apoptosis executive protein, were detected by Western blot to evaluate the apoptosis levels of cells., Results: Infection with both the T. gondii ToxoDB#9 and RH strains induced an increased expression of miR-185 and a decreased expression of ARAF in mice tissues, PK-15 and 3D4/21 cells. MiR-185 mimic transfections showed a significantly negative correlation in expression levels between miR-185 and the ARAF gene. The dual luciferase reporter assay confirmed that ARAF was a target of miR-185. Functional investigation revealed that T. gondii infection induced the apoptosis of PK-15 and 3D4/21 cells, which could be inhibited by ARAF knockout or overexpression of miR-185. The expression levels of cleaved caspase-3 protein were significantly lower in cells with ARAF knockout than in normal cells, which were consistent with the results of the cell flow cytometry assays., Conclusions: Toxoplasma gondii infection could lead to the upregulation of miR-185 and the downregulation of ARAF, which was not related to the strain of T. gondii and the host cells. Toxoplasma gondii infection could regulate the apoptosis of host cells via the miR-185/ARAF axis, which represents an additional strategy used by T. gondii to counteract host-cell apoptosis in order to maintain survival and reproduce in the host cells., (© 2023. BioMed Central Ltd., part of Springer Nature.)

The aim of the present study was to assess morphologic and genetic data on ascariasis in swine (Sus scrofa domesticus) and humans in low-resource rural and periurban communities in the state of Piauí, Brazil. Our cross-sectional survey included 100 fecal samples obtained from swine and 682 samples from humans. Fifteen pigs were necropsied. Human and porcine fecal samples were examined to identify Ascaris eggs. Parasites obtained in the swine necropsies were studied using scanning electron microscopy (SEM), and the mitochondrial gene encoding the cytochrome oxidase 1 (cox1) enzyme was partially amplified and sequenced for molecular taxonomy and phylogenetic analyses. The overall prevalence of Ascaris eggs in the swine fecal samples was 16/100 (16%). No Ascaris eggs were identified in the human fecal samples. SEM of six worms recovered from pigs demonstrated morphological characteristics of A. suum. Cox1 sequences were compatible with A. suum reference sequences. Original and reference (GenBank) nucleotide sequences were organized into clusters that did not segregate the parasites by host species or and region. The largest haplogroups were dominated by haplotypes H01, H02 and H31. In the communities studied, there was no epidemiological evidence of the zoonotic transmission of ascariasis at the human-swine interface.

Background: Pigs (Sus scrofa domesticus), an important domestic livestock, are generally affected by helminth and protozoan parasites. Rearing pigs in rural regions in Nepal is a common practice for subsistence farming. A cross-sectional survey was conducted to determine the occurrence of gastrointestinal parasites (GIPs) in pigs raised in Western Nepal., Methods: A total of 200 faecal samples from commercial and smallholder farms were examined by wet mounts, flotation, sedimentation and staining techniques., Results: The results revealed that overall 86.5% of samples were found shedding oocysts or eggs of one or more GIPs. Three species of protozoa [Eimeria sp. (26%), Entamoeba coli (25.5%) and Coccidia (29%)] and nine species of helminths parasites (Ascaris suum (32.5%), Trichuris suis (30%), strongyle-type nematode (27.5%), hookworm (26%), Fasciola sp. (17.5%), Physaloptera sp. (17.5%), Strongyloides sp. (17.5%), Metastrongylus sp. (8%) and Oesophagostomum sp. (5.5%)] were identified. Female pigs were found to have higher protozoan infection than males, but such a difference was not noticed with regard to helminth parasites. Strongyles and Oesophagostomum infection were higher in commercial farms compared to smallholder farms, whereas the prevalences of E. coli and other protozoans were higher in smallholder farms. Among the contextual factors evaluated for association, weight and gender of pigs, and annual income and gender of managers/caretakers were significantly (p < 0.05) associated with the prevalence of GIPs in pigs. The overall prevalence of certain helminths such as strongyle-type nematode and A. suum was significantly (p < 0.05) associated with the weight of pigs after adjusting other contextual factors., Conclusions: This study detected relatively high prevalence of intestinal parasites in domestic pig facilities. Molecular epidemiological studies are essential to verify the exact zoonotic potential of parasites carried by pigs in the region. An effective periodic monitoring of GIPs of pigs needs to be carried out to minimize their further dissemination., (© 2023 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Cysticercosis is a neglected tropical disease caused by the larval stage of the zoonotic tapeworm (Taenia solium). While there is a clear spatial component in the occurrence of the parasite, no geostatistical analysis of active human cysticercosis has been conducted yet, nor has such an analysis been conducted for Sub-Saharan Africa, albeit relevant for guiding prevention and control strategies. The goal of this study was to conduct a geostatistical analysis of active human cysticercosis, using data from the baseline cross-sectional component of a large-scale study in 60 villages in Burkina Faso. The outcome was the prevalence of active human cysticercosis (hCC), determined using the B158/B60 Ag-ELISA, while various environmental variables linked with the transmission and spread of the disease were explored as potential explanatory variables for the spatial distribution of T. solium. A generalized linear geostatistical model (GLGM) was run, and prediction maps were generated. Analyses were conducted using data generated at two levels: individual participant data and grouped village data. The best model was selected using a backward variable selection procedure and models were compared using likelihood ratio testing. The best individual-level GLGM included precipitation (increasing values were associated with an increased odds of positive test result), distance to the nearest river (decreased odds) and night land temperature (decreased odds) as predictors for active hCC, whereas the village-level GLGM only retained precipitation and distance to the nearest river. The range of spatial correlation was estimated at 45.0 [95%CI: 34.3; 57.8] meters and 28.2 [95%CI: 14.0; 56.2] km for the individual- and village-level datasets, respectively. Individual- and village-level GLGM unravelled large areas with active hCC predicted prevalence estimates of at least 4% in the south-east, the extreme south, and north-west of the study area, while patches of prevalence estimates below 2% were seen in the north and west. More research designed to analyse the spatial characteristics of hCC is needed with sampling strategies ensuring appropriate characterisation of spatial variability, and incorporating the uncertainty linked to the measurement of outcome and environmental variables in the geostatistical analysis. Trial registration: ClinicalTrials.gov; NCT0309339., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Dermauw et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Trichinosis is a parasitic infection with worldwide distribution, which is caused by consuming pork or other meats containing cystic larvae of the parasitic nematode Trichinella Spiralis . This study aimed to investigate the status of infection  Trichinella Spiralis  in domestic and wild animals. To study the spread of trichinelles in animals, a retrospective analysis was conducted based on the study of research journals and conducted their research methods of compressor trichinelloscopy (microscopic) and digestion of samples in artificial gastric juice (biochemical). A total of 17 positive samples were detected for trichinellosis during the observation period, of which 58.8% belonged to a badger ( Meles Meles ), and 35.3% to the brown bear ( Ursusarctos ), and only 5.9% of wild boar ( Susscrofa ). The mean long-term extent of infection belonged to badgers (18.2%), bears (7.9%), and wild boars (0.05%). The study found that between 2015 and 2020, seventeen Trichinella cases were recorded among wildlife in the Tyumen region and the Khanty-Mansi Autonomous Region. The number of annual Trichinella detection cases was declining, indicating the effectiveness of veterinary services. This study determined that the primary source of infection was bears, badgers, and wild boars. Among the 17 positive samples, 58.8% belonged to the badger, 35.3% to the bear, and only 5.9% to the wild boar., Competing Interests: The authors declare that they have no conflict of interest.

Background: Taenia solium is a tapeworm that causes taeniosis in humans and cysticercosis in humans and pigs. Within Eastern and Southern Africa (ESA), information on the presence of human taeniosis and cysticercosis seems scarce. This systematic review aimed to describe the current information available and gaps in the epidemiology of human T. solium infections in ESA., Methods/principle Findings: Scientific literature published between 1st January 2000 and 20th June 2022 in international databases [MEDLINE (Ovid), Embase (Ovid), Global Health (Ovid), Scopus (Elsevier), African Index Medicus (via WHO Global Index Medicus), and Open Grey] was systematically reviewed for ESA. The study area included 27 countries that make up the ESA region. Information on either taeniosis, cysticercosis or NCC was available for 16 of 27 countries within the region and a total of 113 reports were retained for the review. Most case reports for cysticercosis and NCC were from South Africa, while Tanzania had the most aggregated cysticercosis reports. Eleven countries reported on NCC with seven countries reporting data on NCC and epilepsy. Unconfirmed human T. solium taeniosis cases were reported in nine countries while two countries (Madagascar and Zambia) reported confirmed T. solium cases. The cysticercosis seroprevalence ranged between 0.7-40.8% on antigen (Ag) ELISA and between 13.1-45.3% on antibody (Ab) ELISA. Based on immunoblot tests the Ab seroprevalence was between 1.7-39.3%, while the proportion of NCC-suggestive lesions on brain CT scans was between 1.0-76% depending on the study population. The human taeniosis prevalence based on microscopy ranged between 0.1-14.7%. Based on Copro Ag-ELISA studies conducted in Kenya, Rwanda, Tanzania, and Zambia, the highest prevalence of 19.7% was reported in Kenya., Conclusions: Despite the public health and economic impact of T. solium in ESA, there are still large gaps in knowledge about the occurrence of the parasite, and the resulting One Health disease complex, and monitoring of T. solium taeniosis and cysticercosis is mostly not in place., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zulu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The porcine roundworm Ascaris suum impairs feed conversion and weight gain, but its effects on intestinal microbiota remain largely unexplored., Methods: Modulation of the intestinal microbiota was assessed in pigs that were infected once with 10,000 A. suum eggs and pigs that received a trickle infection (1000 eggs/day over 10 days), compared with a non-infected control group. Six pigs each were sacrificed per group at days 21, 35 and 49 post-infection (p.i.). Faecal samples taken weekly until slaughter and ingesta samples from different intestinal compartments were subjected to next-generation sequencing of the bacterial 16S rRNA gene., Results: The results revealed marked differences between the single- and the trickle-infected group. Single infection caused a remarkable but transient decrease in microbial diversity in the caecum, which was not observed in the trickle-infected group. However, an increase in short-chain fatty acid-producing genera in the caecum on day 21 p.i., which shifted to a decrease on day 35 p.i., was common to both groups, possibly related to changes in excretory-secretory products following the parasite's final moult. Faecal microbial interaction networks were more similar between the single-infected and control group than the trickle-infected group. In addition, a lower degree of similarity over time indicated that A. suum trickle infection prevented microbiota stabilization., Conclusions: These different patterns may have important implications regarding the comparability of experimental infections with natural scenarios characterized by continuous exposure, and should be confirmed by further studies., (© 2022. The Author(s).)

Toxoplasma gondii infections are usually asymptomatic in pigs, and an acute clinical disease is rare in this host. This study aimed to determine the pathological and molecular aspects of an outbreak of fatal systemic toxoplasmosis in finishing pigs in Brazil. The outbreak occurred on a commercial finishing pig farm in the state of Santa Catarina in southern Brazil. The farm had 1500 pigs and 3.8% of mortality rate during the outbreak. The pigs had fever, anorexia, apathy, and locomotor deficits. Seven pigs were necropsied. Gross findings included multifocal to coalescent pale areas in skeletal muscles, lymphadenomegaly, hepatosplenomegaly, and non-colapsed lungs. The histological findings included granulomatous lymphadenitis, hepatitis and splenitis, necrotizing myositis, and lymphoplasmacytic interstitial pneumonia. Lung and liver lesions were occasionally accompanied by T. gondii parasitic structures. Positive immunolabeling for T. gondii tachyzoites and encysted bradyzoites was detected in all examined pigs. PCR-RFLP (11 markers) and microsatellite analysis (15 markers) identified the non-archetypal genotype #278 in pigs. This is the first report of systemic toxoplasmosis in pigs with muscle lesions and additionally shows the diversity of disease-causing T. gondii genotypes circulating in animals in Brazil.

The seroprevalence of Sarcocystis spp. and Toxoplasma gondii was researched in swine raised in Santa Maria, RS, Brazil. Serum samples from 84 pigs from 31 farms were tested using indirect immunofluorescence assay (IFA) for both agents. Additionally, 53 samples of pork sausages and tissues destined for human consumption, including: salami, sausage, black pudding, heart, tongue, brain, and rib muscle, were submitted to PCR to detect DNA for each agent. The frequency of anti-Sarcocystis spp. antibodies was 36.9% (31/84), with titers ranging from 32 to 1024, and 25% (21/84) for anti-T. gondii antibodies, with titers ranging from 64 to 2048. Sarcocystis spp. and T. gondii DNA were detected in 67.9% (36/53) and 13.2% (7/53) of samples, respectively. The presence of antibodies and the detection of DNA from Sarcocystis spp., and T. gondii suggests that the pigs were infected and may serve as an important reservoir for both parasites. The infection by these protozoa in the swine population is relevant to public health due to their zoonotic potential.

Background: Infections with Ascaris lumbricoides and Trichuris trichiura remain significant contributors to the global burden of neglected tropical diseases. Infection may in particular affect child development as they are more likely to be infected with T. trichiura and/or A. lumbricoides and to carry higher worm burdens than adults. Whilst the impact of heavy infections are clear, the effects of moderate infection intensities on the growth and development of children remain elusive. Field studies are confounded by a lack of knowledge of infection history, nutritional status, presence of co-infections and levels of exposure to infective eggs. Therefore, animal models are required. Given the physiological similarities between humans and pigs but also between the helminths that infect them; A. suum and T. suis, growing pigs provide an excellent model to investigate the direct effects of Ascaris spp. and Trichuris spp. on weight gain., Methods and Results: We employed a trickle infection protocol to mimic natural co-infection to assess the effect of infection intensity, determined by worm count (A. suum) or eggs per gram of faeces (A. suum and T. suis), on weight gain in a large pig population (n = 195) with variable genetic susceptibility. Pig body weights were assessed over 14 weeks. Using a post-hoc statistical approach, we found a negative association between weight gain and T. suis infection. For A. suum, this association was not significant after adjusting for other covariates in a multivariable analysis. Estimates from generalized linear mixed effects models indicated that a 1 kg increase in weight gain was associated with 4.4% (p = 0.00217) decrease in T. suis EPG and a 2.8% (p = 0.02297) or 2.2% (p = 0.0488) decrease in A. suum EPG or burden, respectively., Conclusions: Overall this study has demonstrated a negative association between STH and weight gain in growing pigs but also that T. suis infection may be more detrimental that A. suum on growth., Competing Interests: The authors have declared that no competing interests exist.

Metastrongylosis is an infection of the respiratory tract of pigs caused by parasites of the genus Metastrongylus , whose eggs are similar to other Strongylida through light microscopy; species-specific identification can be performed with molecular tools. We explored the species composition and the genetic diversity of Metastrongylus infecting pigs in close contact with humans in impoverished rural communities in the state of Piauí, in northeastern Brazil. Fecal samples ( n  = 78) were collected for parasitologic tests. Egg morphometry and molecular characterization, using the cytochrome c oxidase subunit 1 ( cox 1) gene, were performed. For strongyliform eggs, 62 of 78 (80%) pigs were positive and 6 of 99 (6%) eggs had dimensions compatible with Metastrongylus . Of the 37 samples submitted to PCR, 10 were identified as M. salmi . We found 3 M. salmi haplotypes, including 2 new and 1 described previously in Europe. Overall, M. salmi demonstrated lower intraspecific genetic diversity: diversity index (H) ± SD = 0.318 ± 0.164, n  = 12, compared with published M. pudendotectus sequences (1.000 ± 0.272, n  = 3). To our knowledge, M. salmi DNA sequences have not been published previously from pigs in South America.

Background: Neurocysticercosis (NCC) is the infection of the human central nervous system (CNS) by Taenia solium larvae that cause significant neurological morbidity. Studies on NCC pathophysiology, host-parasite interactions or therapeutic agents are limited by the lack of suitable animal models. We have previously reported that carotid injection of activated T. solium oncospheres directs parasites into the CNS and consistently reproduces NCC. This study assessed the minimal dose required to consistently obtain NCC by intracarotid oncosphere injection and compared antigen and antibody response profiles by dose-group., Methods/principal Findings: Three groups of pigs were infected with either 2500 (n = 10), 5000 (n = 11), or 10000 (n = 10) oncospheres. Two pigs died during the study. Necropsy exam at day 150 post-infection (PI) demonstrated viable NCC in 21/29 pigs (72.4%), with higher NCC rates with increasing oncosphere doses (4/9 [44.4%], 9/11 [81.8%] and 8/9 [88.9%] for 2500, 5000, and 10000 oncospheres respectively, P for trend = 0.035). CNS cyst burden was also higher in pigs with increasing doses (P for trend = 0.008). Viable and degenerated muscle cysticerci were also found in all pigs, with degenerated cysticerci more frequent in the 2500 oncosphere dose-group. All pigs were positive for circulating parasite antigens on ELISA (Ag-ELISA) from day 14 PI; circulating antigens markedly increased at day 30 PI and remained high with plateau levels in pigs infected with either 5000 or 10000 oncospheres, but not in pigs infected with 2500 oncospheres. Specific antibodies appeared at day 30 PI and were not different between dose-groups., Conclusion/significance: Intracarotid injection of 5000 or more oncospheres produces high NCC rates in pigs with CNS cyst burdens like those usually found in human NCC, making this model appropriate for studies on the pathogenesis of NCC and the effects of antiparasitic treatment., Competing Interests: The authors have declared that no competing interests exist.

This study aimed to examine the distribution of gastrointestinal parasitic infections in domestic pigs in the Republic of Korea. From May 2020 to October 2021, 364 pig fecal samples were collected from 75 farms in 7 Provinces and microscopically examined. A total of 170 (46.7%) pigs were infected with at least one of the following parasites: Balantioides coli, strongyles, Ascaris suum, Trichuris suis, and coccidia. By parasite species, B. coli, strongyles, A. suum, T. suis, and coccidia oocysts or eggs were detected in 144 (39.6%), 24 (6.6%), 14 (3.8%), 4 (1.1%), and 1 (0.3%) samples, respectively. One hundred fifty-four, 15, and 1 cases showed single, double, and triple infections, respectively. Of the swine fecal samples from 75 farms, 69 specimens (92.0%) were infected with 1 or more parasites. All surveyed farms across the country exhibited a positive rate of over 30%, among which the highest positive rate was 65.0% in Chungcheongnam-do, and Jeollabuk-do was followed by 61.9%. Winter showed a statistically lower prevalence than other seasons. This study showed that gastrointestinal parasites are prevalent in pigs in Korea, although the diversity of parasites is low.

Background: Worldwide, intestinal parasites significantly affect the health and production of pigs., Objective: This study assessed the prevalence of Ascaris and Cryptosporidium infection in pigs in the Ejisu-Juaben Municipality of Ghana., Method: Faecal samples from two hundred (200) pigs on four different farms (labelled A, B, C, D) were processed using the Kinyoun modified Ziehl-Neelsen method for Cryptosporidium and the Formol-ether sedimentation method for Ascaris and microscopically examined to identify parasites to the genus level., Results: The prevalence of Ascaris and Cryptosporidium in the pigs was 76% and 77%, respectively. The weaners had the highest Ascaris prevalence (96.15%) with the piglets recording the least (59.25%). On the other hand, the piglets had the highest prevalence (88.89%) for Cryptosporidium with the boars, sows and weaners recording 75.86%, 75.42% and 73.08% respectively. The prevalence of Ascaris was high in farm D (78.57%) while Cryptosporidium was highest in farm C (86.11%). Generally, there was a significant difference (p = 0.044) in the mean distribution of Cryptosporidium in the pigs., Conclusion: The high burden of Ascaris and Cryptosporidium infections in the pigs suggest the need to adopt and implement effective control measures., (© 2022 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Helminths of the genus Oesophagostomum cause enteric diseases and affect domestic animals such as pigs. The aim of this study was to explore the species composition and genetic diversity of Oesophagostomum spp. infecting pigs in close contact with humans in the state of Piauí, Brazil. Eighty-seven fecal samples were collected for parasitological tests and molecular analysis. Through microscopy, the overall positivity rate for strongyliform eggs was 81.6% among the pigs studied. Forty-two strongyliform egg samples were subjected to PCR and six cox1 sequences (637 bp) were identified for the genus Oesophagostomum. The sequences were identified as Oesophagostomum dentatum, O. quadrispinulatum and O. columbianum. In the phylogenetic tree and haplotype network, 89 sequences were separated into seven clusters, which also included reference sequences from GenBank. Oesophagostomum dentatum and O. quadrispinulatum were seen to be closely related species and formed a monophyletic group related to O. aculeatum. Oesophagostomum columbianum showed similarity with sequences from parasites infecting small ruminants and the clade was positioned closer to O. bifurcum. High interspecific diversity was found and intraspecific diversity varied according to the species. This was the first study to characterize Oesophagostomum DNA sequences obtained from pigs in Brazil.

Dietary probiotics may enhance gut health by directly competing with pathogenic agents and through immunostimulatory effects. These properties are recognized in the context of bacterial and viral pathogens, but less is known about interactions with eukaryotic pathogens such as parasitic worms (helminths). In this study we investigated whether two probiotic mixtures (comprised of Bacillus amyloliquefaciens, B. subtilis , and Enterococcus faecium [BBE], or Lactobacillus rhamnosus LGG and Bifidobacterium animalis subspecies Lactis Bb12 [LB]) could modulate helminth infection kinetics as well as the gut microbiome and intestinal immune responses in pigs infected with the nodular worm Oesophagostomum dentatum . We observed that neither probiotic mixture influenced helminth infection levels. BBE, and to a lesser extent LB, changed the alpha- and beta-diversity indices of the colon and fecal microbiota, notably including an enrichment of fecal Bifidobacterium spp. by BBE. However, these effects were muted by concurrent O. dentatum infection. BBE (but not LB) significantly attenuated the O. dentatum -induced upregulation of genes involved in type-2 inflammation and restored normal lymphocyte ratios in the ileo-caecal lymph nodes that were altered by infection. Moreover, inflammatory cytokine release from blood mononuclear cells and intestinal lymphocytes was diminished by BBE. Collectively, our data suggest that selected probiotic mixtures can play a role in maintaining immune homeostasis during type 2-biased inflammation. In addition, potentially beneficial changes in the microbiome induced by dietary probiotics may be counteracted by helminths, highlighting the complex inter-relationships that potentially exist between probiotic bacteria and intestinal parasites., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Myhill, Stolzenbach, Mejer, Krych, Jakobsen, Kot, Skovgaard, Canibe, Nejsum, Nielsen, Thamsborg and Williams.)

Background: The existence of an animal reservoir of Trypanosoma brucei gambiense (T. b. gambiense), the agent of human African trypanosomiasis (HAT), may compromise the interruption of transmission targeted by World Health Organization. The aim of this study was to investigate the presence of trypanosomes in pigs and people in the Vavoua HAT historical focus where cases were still diagnosed in the early 2010's., Methods: For the human survey, we used the CATT, mini-anion exchange centrifugation technique and immune trypanolysis tests. For the animal survey, the buffy coat technique was also used as well as the PCR using Trypanosoma species specific, including the T. b. gambiense TgsGP detection using single round and nested PCRs, performed from animal blood samples and from strains isolated from subjects positive for parasitological investigations., Results: No HAT cases were detected among 345 people tested. A total of 167 pigs were investigated. Free-ranging pigs appeared significantly more infected than pigs in pen. Over 70% of free-ranging pigs were positive for CATT and parasitological investigations and 27-43% were positive to trypanolysis depending on the antigen used. T. brucei was the most prevalent species (57%) followed by T. congolense (24%). Blood sample extracted DNA of T. brucei positive subjects were negative to single round TgsGP PCR. However, 1/22 and 6/22 isolated strains were positive with single round and nested TgsGP PCRs, respectively., Discussion: Free-ranging pigs were identified as a multi-reservoir of T. brucei and/or T. congolense with mixed infections of different strains. This trypanosome diversity hinders the easy and direct detection of T. b. gambiense. We highlight the lack of tools to prove or exclude with certainty the presence of T. b. gambiense. This study once more highlights the need of technical improvements to explore the role of animals in the epidemiology of HAT., Competing Interests: The authors have declared that no competing interests exist.

Background: The pork tapeworm (Taenia solium) is a parasitic helminth that imposes a major health and economic burden on poor rural populations around the world. As recognized by the World Health Organization, a key barrier for achieving control of T. solium is the lack of an accurate and validated simulation model with which to study transmission and evaluate available control and elimination strategies. CystiAgent is a spatially-explicit agent based model for T. solium that is unique among T. solium models in its ability to represent key spatial and environmental features of transmission and simulate spatially targeted interventions, such as ring strategy., Methods/principal Findings: We validated CystiAgent against results from the Ring Strategy Trial (RST)-a large cluster-randomized trial conducted in northern Peru that evaluated six unique interventions for T. solium control in 23 villages. For the validation, each intervention strategy was replicated in CystiAgent, and the simulated prevalences of human taeniasis, porcine cysticercosis, and porcine seroincidence were compared against prevalence estimates from the trial. Results showed that CystiAgent produced declines in transmission in response to each of the six intervention strategies, but overestimated the effect of interventions in the majority of villages; simulated prevalences for human taenasis and porcine cysticercosis at the end of the trial were a median of 0.53 and 5.0 percentages points less than prevalence observed at the end of the trial, respectively., Conclusions/significance: The validation of CystiAgent represented an important step towards developing an accurate and reliable T. solium transmission model that can be deployed to fill critical gaps in our understanding of T. solium transmission and control. To improve model accuracy, future versions would benefit from improved data on pig immunity and resistance, field effectiveness of anti-helminthic treatment, and factors driving spatial clustering of T. solium infections including dispersion and contact with T. solium eggs in the environment., Competing Interests: The authors have declared that no competing interests exist.

Background: The roundworm Ascaris suum is one of the parasites with the greatest economic impact on pig farming. In this context, lower weight gain is hypothesized to be due to decreased nutrient absorption. This study aims at characterizing the effects of A. suum infection on intestinal nutrient transport processes and potential molecular mechanisms., Methods: Three groups of six piglets each were infected orally (10,000 embryonated A. suum eggs) in a single dose ("single infection"). Another three groups were infected orally (1000 embryonated eggs) for 10 consecutive days ("trickle infection"). Animals were necropsied 21, 35 and 49 days post-infection (dpi). Three groups served as respective controls. The Ussing chamber technique was applied for the functional characterization of small intestinal tissues [short-circuit currents (I sc ) as induced by glucose, alanine and peptides; 3 H-glucose net flux rates; tissue conductance (G t )]. Transcription and expression levels of relevant cytokines and nutrient transporters were evaluated (qPCR/western blot)., Results: Peptide- and alanine-induced changes in I sc were significantly decreased in the jejunum and ileum of the trickle-infected group at 49 dpi and in the ileum of the single-infected group at 49 dpi. No significant differences regarding glucose transport were observed between the Ascaris-infected groups and the control group in Ussing chamber experiments. Transcription levels of the glucose and peptide transporters as well as of selected transcription factors (transcription of signal transducer and activator of transcription 6 [STAT6] and hypoxia-inducible factor 1-alpha [Hif-1α]) were significantly increased in response to both infection types after some periods. The transcription of interleukins 4 and 13 varied between decrease and increase regarding the respective time points, as did the protein expression of glucose transporters. The expression of the peptide transporter PepT1 was significantly decreased in the ileal single-infected group at 35 dpi. Hif-1α was significantly increased in the ileal tissue from the single-infected group at 21 dpi and in the trickle-infected group at 35 dpi. The expression levels of Na + /K + -ATPase and ASCT1 remained unaffected., Conclusions: In contrast to the current hypothesis, these results indicate that the nutrient deprivation induced by A. suum cannot be explained by transcriptional or expression changes alone and requires further studies., (© 2021. The Author(s).)

Background: Trichinella spiralis is a zoonotic food-borne parasite. A disease caused by infection with T. spiralis is called trichinellosis in humans. It is important to investigate the epidemic situation and the surveillance of herds and then prevent infection in humans. Therefore, this study is to develop a rapid and sensitive diagnostic method for on-site test in domestic and wild animals., Methods: Upconverting phosphor nanoparticles (UCNPs), an excellent optical label, were conjugated with the excretory-secretory (ES) antigens from T. spiralis muscle larvae (ML) or goat anti-rabbit IgG, and a lateral flow (LF) assay based on these probes (UCNPs-ES/goat anti-rabbit IgG) was developed for the rapid and sensitive detection of anti-T. spiralis IgG antibodies in pig serum. The assay is named the UPT-LF-ES assay. In addition, the probes were characterized, and the assay was optimized. A cut-off threshold of the assay was also identified by using 169 known negative pig samples. Performance of the assay to T. spiralis with different infective numbers, cross-reactivity with other parasitic infections, the single-blinded experiment, and coincidence were evaluated with the assay., Results: The UPT-LF-ES assay was successfully constructed and optimized based on the probes of UCNPs-ES/goat anti-rabbit IgG. In the pigs infected with 100, 1000, and 10,000 ML, positive results were first presented at 35 days post-infection (dpi), 30 dpi, and 25 dpi, respectively. The assay had no cross-reaction with other parasitic infections. A single-blinded experiment indicated that the sensitivity and specificity of the UPT-LF-ES assay were 100% and 100%, respectively, the area under the receiver operating characteristic (ROC) curve was 1.000. In addition, the value detected by the UPT-LF-ES assay was significantly different between positive and negative samples. Moreover, compared with the "gold standard" magnetic stirrer method, the coincidence rate of the UPT-LF-ES assay was 87.27%, and the kappa (K) coefficient was 0.7454, showing a substantial agreement., Conclusions: The UPT-LF-ES assay is a useful point-of-care test (POCT) with T. spiralis in the detection of pig, which contributes to preventing human trichinellosis., (© 2021. The Author(s).)

Background: Intestinal parasites have a significant impact on productivity of pigs. Additionally, presence of zoonotic parasites in pig faeces used as fertilizer and ingestion of raw or undercooked pork products originated from parasite-infested pigs pose a risk to human health., Objectives: The aim of the study was to estimate the prevalence and diversity of gastrointestinal (GI) parasites in indigenous pigs (Sus domesticus) maintained under traditional rearing system in Nepal., Methods: Fresh faecal samples (n = 100) were collected from the pigs of varying age and sex maintained in 18 small-scale farms in south-central Nepal. Samples were processed using various standard methods and examined for parasite eggs, cysts or oocysts., Results: Prevalence of GI parasites in indigenous pigs was 91%, comprising of 14 different genera of protozoans and helminths. Male pigs generally had a higher (97.5%) prevalence of GI parasites than females (87%). While 90% of the suckling and weaner piglets were positive for the GI parasites, all growers and 85% the adult pigs were infected with the parasites. Entamoeba spp. were the primary protozoans in all age groups. Strongyloides sp. was more prevalent helminths in suckling and weaner piglets, whereas Ascarid spp. were higher in both growers and adults. Triplet infection was higher (33.3%) in suckling and weaner piglets, while quadruplet and pentuplet infections were higher (p < .05) among growers (46.7%) and adults (30%), respectively., Conclusions: The indigenous pigs harbour a higher prevalence and greater diversity of GI parasites. GI parasitism varies by sex and age of the pigs., (© 2021 The Authors Veterinary Medicine and Science Published by John Wiley & Sons Ltd.)

Toxoplasma gondii is a globally wide-spread parasite that infects almost all species of mammals and birds, including humans. We studied the spatial distribution of individual T. gondii-seropositive wild boar in Gifu Prefecture (10,621 km 2 ), Japan. Altogether, 744 wild boars were captured at 663 points around human settlements in Gifu Prefecture. Serum samples were collected after recording the exact capture locations, along with each wild boar's body length and sex. We then used a commercial enzyme-linked immunosorbent assay kit for swine to measure anti-T. gondii antibodies in these animals. Among the 744 wild boars, 169 tested positive for T. gondii (22.7%). No significant difference in T. gondii seroprevalence was observed between the mountainous northern region with high winter snow cover and the mild-wintered geographical plain of the southern part of the prefecture. In contrast, 8 of the 11 wild boars that were captured in a public park surrounded by residential areas showed T. gondii seropositivity (72.7%), a value significantly higher than those of the wild boar populations in the other prefecture areas. This in-depth analysis, which spans the big city suburbs and rural areas of a whole prefecture, explains the seroprevalence of zoonotic T. gondii in wild boar and has public health implications., (© 2021. The Author(s).)

Objectives: Trichinella spiralis is a zoonotic parasite with a complex parasitic life cycle and exposed to animals or humans by infectious meat. To control transmissions of T. spiralis through the food chain to humans, sensitive and selective multihost sera-diagnosis is urgent needed for monitoring T. spiralis exposure., Methods: A competition enzyme-linked immunosorbent assay (cELISA) for T. spiralis infection diagnosis in multihost sera was developed based on recombinant cystatin-like protein (rCLP-cELISA) as well as monoclonal antibodies. The sensitivity and accuracy of the rCLP-cELISA were quantified using swine (n = 1316), mice (n = 189) and human (n = 157) serum samples. T. spiralis-antibody targeting test ability of the rCLP-cELISA in swine (n = 22) and human (n = 36), instead of other parasites or viruses antibodies, was evaluated., Results: The rCLP-cELISA showed high agreement with commercial ELISA kits in field swine sera assessed by Cohen's kappa value (κ = 0.7963). And it showed 100% specificity in human trichinellosis detection with sensitivity of 96.49%, no cross-reaction with other parasite or virus infections, and high positive detection rate of 87.5% in low-dose infected swine. Besides, the rCLP-cELISA exhibited potential in the detection of T. spiralis, T. nelsoni and Trichinella T8 infections., Conclusions: The rCLP-cELISA can be used for T. spiralis-associated antibody test in multihost sera., Competing Interests: The authors have declared that no competing interests exist.

Background: Toxoplasmosis caused by Toxoplasma gondii is a serious disease threatening human and animal health. People can be infected with T. gondii by ingesting raw pork contaminated with cysts or oocysts. Serological test is a sensitive and specific method usually used for large-scale diagnosis of T. gondii infection in humans and animals (such as pigs). Commercial pig Toxoplasma antibody ELISA diagnostic kits are expensive, which limits their use; moreover, the wide antigen composition used in these diagnostic kits is still unclear and difficult to standardize. The multiepitope peptide antigen is a novel diagnostic marker, and it has potential to be developed into more accurate and inexpensive diagnostic kits., Methods: The synthetic multiepitope antigen (MAG) cDNA encoding a protein with epitopes from five T. gondii-dominant antigens (SAG1, GRA1, ROP2, GRA4, and MIC3) was designed, synthesized, and expressed in Escherichia coli BL21 (DE3) strain. The recombinant protein was detected through western blot with pig anti-T. gondii-positive and -negative serum, and then IgG enzyme-linked immunosorbent assay (ELISA) named MAG-ELISA was designed. The MAG-ELISA was evaluated in terms of specificity, sensitivity, and stability. The MAG-ELISA was also compared with a commercial PrioCHECK ® Toxoplasma Ab porcine ELISA (PrioCHECK ELISA). Finally, the trend of pig anti-T. gondii IgG levels after artificial infection with RH tachyzoites was evaluated using MAG-ELISA and two other ELISA methods (rMIC3-ELISA and PrioCHECK ELISA)., Results: MAG antigen could be specifically recognized by pig anti-T. gondii-positive but not -negative serum. MAG-ELISA showed high diagnostic performance in terms of specificity (88.6%) and sensitivity (79.1%). MAG-ELISA could be used for detecting anti-T. gondii IgG in the early stage of T. gondii infection in pigs (at least 7 days after artificial infection)., Conclusions: Our results suggest that MAG antigen can be applied to specifically recognize anti-T. gondii IgG in pig, and MAG-ELISA has the potential for large-scale screening tests of T. gondii infection in pig farms and intensive industries., (© 2021. The Author(s).)

Background: Trichinella spiralis ranks seventh in the risk posed by foodborne parasites. It causes most human cases of trichinellosis and is the most frequent cause of Trichinella outbreaks on pig farms and in wild boar, worldwide. Veterinary inspectors seek the source of outbreaks in hopes of limiting the spread. Established molecular tools are inadequate for distinguishing among potential T. spiralis infection sources because genetic variability in these zoonotic pathogens is limited in Europe. Microsatellite markers proved successful in tracing an outbreak of T. britovi, a related parasite harboring much more genetic variation. Here, we successfully employed microsatellite markers to determine the genetic structure of T. spiralis isolates from two pig outbreaks, discovering notable uniformity among parasites within each farm and discovering an epidemiological link between these two outbreaks., Methods: The individual larvae from five isolates of T. spiralis from two pig farms and from ten wild boars were genotyped using nine microsatellite markers to examine their genetic structure., Results: Notably uniform parasite populations constituted each farm outbreak, and the parasites from the first and second outbreaks resembled each other to a notable degree, indicating an epidemiological link between them. Wild boar harbored more genetically variable larval cohorts, distinguishing them from parasites isolated from domestic pigs., Conclusions: Microsatellite markers succeeded in distinguishing isolates of the highly homogeneous T. spiralis, aiding efforts to track transmission. Each outbreak was composed of a homogenous group of parasites, suggesting a point source of contamination., (© 2021. The Author(s).)

Trichinellosis, which is caused by nematodes of the genus Trichinella, is one of the most important zoonotic parasite diseases in the world. A rapid and sensitive immunochromatographic strip (ICS) based on Eu (III) nanoparticles (EuNPs) was developed for the detection of Trichinella spiralis (T. spiralis) infection in pigs. T. spiralis muscle larvae excretory secretory or preadult worm excretory secretory (ML-ES or PAW-ES) antigens were conjugated with EuNPs probes to capture T. spiralis-specific antibodies in pig sera, after which the complex bound to mouse anti-pig IgG deposited on the test line (T-line), producing a fluorescent signal. In the pigs infected with 100, 1000 and 10 000 ML, seroconversion was first detectable for the EuNPs-ML-ES ICS at 30, 25 and 21 days post-infection (dpi) and for the EuNPs-PAW-ES ICS at 25, 21 and 17 dpi. These results show that EuNPs-PAW-ES ICS detects anti-Trichinella IgG in pigs 4-5 days earlier that test using ML-ES antigens. Our ICS have no cross reaction with other parasite infection sera. Furthermore, the detection process could be completed in 10 min. This study indicated that our ICS can be used for the detection of the circulating antibodies in early T. spiralis infection and provide a novel method for on-site detection of T. spiralis infection in pigs.

Background: Taenia solium (T. solium), is a zoonotic helminth causing three diseases namely; taeniasis (in humans), neurocysticercosis (NCC, in humans) and porcine cysticercosis (PCC, in pigs) and is one of the major foodborne diseases by burden. The success or failure of control options against this parasite in terms of reduced prevalence or incidence of the diseases may be attributed to the contextual factors which underpin the design, implementation, and evaluation of control programmes., Methodology/principal Findings: The study used a mixed method approach combining systematic literature review (SLR) and key informant interviews (KII). The SLR focused on studies which implemented T. solium control programmes and was used to identify the contextual factors and enabling environment relevant to successful inception, planning and implementation of the interventions. The SLR used a protocol pre-registered at the International prospective register of systematic reviews (PROSPERO) number CRD42019138107 and followed PRISMA guidelines on reporting of SLR. To further highlight the importance and interlinkage of these contextual factors, KII were conducted with researchers/implementers of the studies included in the SLR. The SLR identified 41 publications that had considerations of the contextual factors. They were grouped into efficacy (10), effectiveness (28) and scale up or implementation (3) research studies. The identified contextual factors included epidemiological, socioeconomic, cultural, geographical and environmental, service and organizational, historical and financial factors. The enabling environment was mainly defined by policy and strategies supporting T. solium control., Conclusion/significance: Failure to consider the contextual factors operating in target study sites was shown to later present challenges in project implementation and evaluation that negatively affected expected outcomes. This study highlights the importance of fully considering the various domains of the context and integrating these explicitly into the plan for implementation and evaluation of control programmes. Explicit reporting of these aspects in the resultant publication is also important to guide future work. The contextual factors highlighted in this study may be useful to guide future research and scale up of disease control programmes and demonstrates the importance of close multi-sectoral collaboration in a One Health approach., Competing Interests: The authors have declared that no competing interests exist.

Toxoplasma gondii parasites present strong but geographically varied signatures of population structure. Populations sampled from Europe and North America have commonly been defined by over-representation of a small number of clonal types, in contrast to greater diversity in South America. The occurrence and extent of genetic diversity in African T. gondii populations remains understudied, undermining assessments of risk and transmission. The present study was designed to establish the occurrence, genotype and phylogeny of T. gondii in meat samples collected from livestock produced for human consumption (free-range chickens, n = 173; pigs, n = 211), comparing with T. gondii detected in blood samples collected from seropositive pregnant women (n = 91) in Benue state, Nigeria. The presence of T. gondii DNA was determined using a published nested polymerase chain reaction, targeting the 529 bp multicopy gene element. Samples with the highest parasite load (assessed using quantitative PCR) were selected for PCR-restriction fragment length polymorphism (PCR-RFLP) targeting the surface antigen 3 (SAG3), SAG2 (5' and 3'), beta-tubulin (BTUB) and dense granule protein 6 (GRA6) loci, and the apicoplast genome (Apico). Toxoplasma gondii DNA was detected in all three of the populations sampled, presenting 30.6, 31.3 and 25.3% occurrence in free-range chickens, pigs and seropositive pregnant women, respectively. Quantitative-PCR indicated low parasite occurrence in most positive samples, limiting some further molecular analyses. PCR-RFLP results suggested that T. gondii circulating in the sampled populations presented with a type II genetic background, although all included a hybrid type I/II or II/III haplotype. Concatenation of aligned RFLP amplicon sequences revealed limited diversity with nine haplotypes and little indication of host species-specific or spatially distributed sub-populations. Samples collected from humans shared haplotypes with free-range chickens and/or pigs. Africa remains under-explored for T. gondii genetic diversity and this study provides the first detailed definition of haplotypes circulating in human and animal populations in Nigeria., Competing Interests: The authors have declared that no competing interests exist.

Background: Swine coccidiosis, a protozoan disease caused by coccidia, can result in diarrhoea and weight loss in piglets and even economic losses in the pig industry. Here, we report the first systematic review and meta-analysis of the prevalence of coccidia (including Eimeria spp. and Cystoisospora suis) in pigs in China., Methods: Five databases (PubMed, ScienceDirect, Chinese Web of Knowledge, Wanfang, and Chongqing VIP) were searched and 50 studies (46,926 domestic pigs, 22 provinces) ultimately identified pertaining to the prevalence of coccidia infection from 1980 to 2019. We incorporated the effect size using the random-effects model in the "meta" package in R software and conducted univariate and multivariate meta-regression analyses using a mixed-effects model., Results: The pooled prevalence rate of coccidia in pigs was 21.9%, including the C. suis infection rate of 9.1%. The highest prevalence of coccidia (39.6%) was found in northwest China, and this region also presented the lowest prevalence of C. suis (4.7%). In the subgroup analysis based on sampling year, the highest prevalence of coccidia was detected in 2001 or earlier (32.6%), whereas the lowest rate was found in 2012 or later (14.3%). An opposite trend was observed for C. suis (5.5% in 2000 or earlier vs 14.4% in 2000 or later). The prevalence of coccidia in extensive farming systems (29.5%) was higher than that in intensive farming systems (17.3%). In contrast, the point estimate of C. suis prevalence was lower in the extensive farming systems (5.1%) than in the intensive farming systems (10.0%), but the difference was not significant (P > 0.05). Among the four age categories, the highest total coccidia prevalence (26.2%) was found in finishing pigs, followed by suckling piglets (19.9%), whereas the highest prevalence of C. suis (14.9%) was observed in suckling piglets., Conclusions: Our findings suggest that coccidia infection in Chinese pigs is common, although the prevalence of C. suis in pigs does not receive sufficient attention. We recommend the rational use of anticoccidial drugs to avoid drug resistance and the development of preventive and control measures for C. suis to reduce the incidence of swine coccidiosis.

Trichinella spiralis is an important foodborne parasitic nematode distributed worldwide that infects humans and animals. Glutaminase (GLS) is an important gene in the glutamine-dependent acid resistance (AR) system; however, its role in T. spiralis muscle larvae (ML) remains unclear. The present study aimed to characterize T. spiralis GLS (TsGLS) and assess its function in T. spiralis ML AR both in vitro and in vivo using RNA interference. The results indicated that native TsGLS (72 kDa) was recognized by anti-rTsGLS serum at the muscle larvae stage; moreover, an immunofluorescence assay confirmed that TsGLS was located in the epidermis of ML. After silencing the TsGLS gene, the relative expression of TsGLS mRNA and the survival rate of T. spiralis ML were reduced by 60.11% and 16.55%, respectively, compared to those in the PBS and control groups. In vivo AR assays revealed that the worm numbers at 7 and 35 days post-infection (dpi) decreased by 61.64% and 66.71%, respectively, compared to those in the PBS group. The relative expression of TsGLS mRNA in F 1 generation T. spiralis ML was reduced by 42.52%, compared to that in the PBS group. To the best of our knowledge, this is the first study to report the presence of the glutamine-dependent AR system in T. spiralis. Our results indicate that TsGLS plays a crucial role in the T. spiralis AR system; thus, it could be used as a potential candidate target molecule for producing vaccines against T. spiralis infection.