Parasitology International最新文献

{"title":"Field evaluation of entomological surveillance techniques for leishmaniasis vector sand flies (Diptera: Psychodidae)","authors":"Yasoda Kumari ,&nbsp;Nayana Gunathilaka ,&nbsp;Deepika Amarasinghe ,&nbsp;Bawantha Kasun ,&nbsp;Gayan Nimesh ,&nbsp;Asanka Dinesh ,&nbsp;Mahesha Vishwajith ,&nbsp;Mohamed Asam","doi":"10.1016/j.parint.2026.103232","DOIUrl":"10.1016/j.parint.2026.103232","url":null,"abstract":"<div><div>Leishmaniasis remains a major public health concern in Sri Lanka, as emphasized in the first National Strategic Plan for the Prevention and Control of Leishmaniasis. The lack of a systematic surveillance plan was identified as one of the key challenges to implementing a control programme. Therefore, this study evaluated the efficacy of different entomological techniques for leishmaniasis vector surveillance. Monthly collections were conducted from December 2023 to June 2024 in two Medical Officer of Health areas, Divulapitiya and Mirigama, in the Gampaha District. The surveillance techniques included Cattle Baited Net Trap (CBNT), Hand Collection (HC), Light Trap (LT) with six different light sources (UV, white, green, blue, red, incandescent), Human-baited Double Net Trap (HDNT), and Sticky Trap (ST) with five different colours (white, green, yellow, red, black). A one-way ANOVA was used to compare trap efficiency. A total of 732 sand flies (219 females and 513 males) of six species were collected: <em>Phlebotomus argentipes</em> (43.98%), <em>Sergentomyia zeylanica</em> (52.87%), <em>Sergentomyia punjabensis</em> (2.33%), <em>Sergentomyia dentata</em> (0.27%), <em>Phlebotomus stantoni</em> (0.27%), and <em>Sergentomyia rudnicki</em> (0.27%). Males predominated in all traps except HDNT. The highest species diversity was obtained from LTs, while sand fly density was highest in CBNT (18.14 per trap), followed by HC (5.15), LT (4.25), HDNT (1.3), and ST (0.18). The CBNT was most effective for evaluating sand fly abundance in the study area, while the LT was productive in determining species diversity. The findings of this study emphasize the importance of integrating multiple surveillance techniques to improve the accuracy and effectiveness of leishmaniasis vector monitoring in Sri Lanka.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103232"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145945637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Red blood cell membrane protein polymorphisms related to risk of malaria infection in the population living in malaria-endemic areas of Thailand: An analytic cross-sectional study","authors":"Phunuch Muhamad ,&nbsp;Luxsana Panrit ,&nbsp;Orranee Srikhamdokkhae ,&nbsp;Kotchakorn Laohapensaeng ,&nbsp;Mayuri Tarasuk ,&nbsp;Salmeeyah Sa-I ,&nbsp;Kesara Na-Bangchang","doi":"10.1016/j.parint.2025.103197","DOIUrl":"10.1016/j.parint.2025.103197","url":null,"abstract":"<div><div>Malaria parasites proliferate within red blood cells (RBCs), making host genetic polymorphisms related to RBC proteins a significant factor in the natural selection process for malaria infection. The present study aimed to examine the prevalence of RBC polymorphisms associated with malaria infection among populations living in two malaria-endemic regions: the Thai-Myanmar and Thai-Malaysian borders. DNA samples were analysed for RBC genetic diversity, including MN antigen, MNS blood group subtype Miltenberger (Mi^a), Duffy antigen (including the Duffy gene promoter), and complement receptor-1 (CR-1) polymorphisms at position 981 using PCR-based techniques. The polymorphisms were categorised based on malaria infection status and further analysed to assess their association with malaria risk. A total of 616 blood samples were included in the analysis, comprising 270 samples from individuals infected with malaria and 346 samples from non-infected participants. Notable genotypes observed in malaria-infected and non-infected samples included the MM antigen (61.1 % vs. 46.5 %) and NN antigen (22.2 % vs. 11.1 %) [OR; 3.7 (2.0–6.7), <em>p</em> &lt; 0.0001], as well as the FYA/FYA or FYA/FYB genotypes with the wild-type Duffy blood group promoter (76.1 % vs. 46.9 %) [OR; 4.7 (3.0–7.3), <em>p</em> &lt; 0.0001]. Geographic analysis revealed distinct genetic distributions in each study area. These genetic polymorphisms suggest that the majority of the population in these regions is at increased risk of malaria infection. Understanding the genetic diversity of RBC membrane polymorphisms provides valuable insights for future epidemiological studies and the development of targeted malaria control strategies.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103197"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145564928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A pseudokinase pPK4 is required for efficient red blood cell invasion and exflagellation center formation in Plasmodium yoelii","authors":"Edwin Kimeli Too ,&nbsp;Thant Zin Tun ,&nbsp;Nattawat Chaiyawong ,&nbsp;Takahiro Ishizaki ,&nbsp;Minami Baba ,&nbsp;Hassan Hakimi ,&nbsp;Masahito Asada ,&nbsp;Kazuhide Yahata ,&nbsp;Osamu Kaneko","doi":"10.1016/j.parint.2025.103187","DOIUrl":"10.1016/j.parint.2025.103187","url":null,"abstract":"<div><div>Human malaria, caused by the parasite <em>Plasmodium</em>, is a global health burden, with an estimated 263 million cases and 597,000 deaths in 2023 (WHO, 2024). In vertebrate hosts, malaria parasites multiply by recurrent invasion of the red blood cells (RBCs). Within RBCs, some asexual parasites undergo sexual differentiation to become gametocytes. After a female mosquito ingests a blood meal, micro- and macrogametocytes egress from RBCs and fertilize within the mosquito's midgut. Pseudokinases are a class of proteins that resemble typical kinases, but cannot catalyze phosphorylation reactions. Several <em>Plasmodium</em> pseudokinases have high transcript levels at both the schizont and sexual stages and may play critical roles within both junctures of the lifecycle. We previously reported that one pseudokinase, pPK1, is involved in invading RBCs, as well as exflagellation center formation, using the rodent malaria parasite <em>Plasmodium yoelii</em>. In the present study, we characterized two additional pseudokinases in <em>P. yoelii</em>, pPK3 and pPK4. Both pseudokinases have high transcript levels at the schizont and gametocyte stages; however, pPK3 transcripts are more abundantly detected in macrogametocytes than in microgametocytes. The pattern of pPK4 expression was opposite, with more abundant transcripts observed in microgametocytes. Immunofluorescence assay of transgenic parasites expressing Myc-tagged pPK4 revealed that pPK4 appeared to be expressed in the cytoplasm of schizonts and sexual stages. <em>P. yoelii</em> pPK3 knockout (KO) lines showed no significant growth defects in mice and no significant reduction in the number of oocysts following transmission to mosquitoes. However, the <em>P. yoelii</em> pPK4-KO lines exhibited a significant defect in growth, decreased virulence in mice, and a significant reduction in the number of oocysts in mosquitoes. An <em>in vivo</em> RBC invasion assay for pPK4-KO lines revealed that invasion, but not egress, was affected. There were no significant differences in gametocytemia and egress from RBC for either micro- or macrogametes; however, there was a significant reduction in the number of exflagellation centers. Thus, we conclude that pPK4 plays an important role in RBC invasion and exflagellation center formation. In contrast, pPK3 is not essential in the blood stage and subsequent parasite lifecycle development up to the oocyst stage.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103187"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systemic infection of Prohemistomum vivax and Cyanodiplostomum encysted metacercariae in African catfish (Clarias gariepinus) from a heavily polluted drain at Giza, Egypt: morphological, molecular and histopathological study","authors":"Alaa Eldin Eissa ,&nbsp;Olfat A. Mahdy ,&nbsp;Eman M. Abouelhassan ,&nbsp;Rabia A. El Zlitne ,&nbsp;Abdulsalam Abu Mhara ,&nbsp;Asmaa K. Al-Mokaddem ,&nbsp;Eman H. Rashwan ,&nbsp;Reham H. Ragab ,&nbsp;Nehal A. Younis","doi":"10.1016/j.parint.2025.103159","DOIUrl":"10.1016/j.parint.2025.103159","url":null,"abstract":"<div><div>Aquatic environmental pollution could be a direct trigger of infection through cercarial invasion to skin / gills or indirectly as a predisposing factor that damage the physical barriers of targeted fish resulting in high intensities of EMC infections in all fish vital organs. In the current study, a total of 150 African catfish (<em>Clarias gariepinus</em>) were randomly collected from Mariotteya drain all the way through the Egyptian township of Shabramant located at the historical heart of Giza. Catfish samples were collected in mid-summer during the period from June to July 2024. A well-documented surge in unionized ammonia, water alkalinity, marked decline in dissolved oxygen together with decreased transparency were signaling a chronic case of agricultural and municipal pollution in which all physical mucosal immunological barriers were harshly suppressed. This environmental disruption has resulted in cellular, biological and pathological alterations in which the invasion of digenean cercariae was favored as documented in the histopathological sections made from affected tissues. Parasitological examination revealed the presence of two distinct EMC belonging to <em>Prohemistomum vivax</em> and <em>Cyanodiplostomum</em> spp. which were presumptively identified using the regular morpho-taxonomical methods and confirmed utilizing the sequencing of the ITS2 rDNA gene which is considered good marker in the differentiation between the digenean species and the phylogeny analysis. Histopathological examination of sampled fish tissues has revealed that EMC infection was not only limited to fish musculatures, yet it extends to internal organs including spleen and kidney to present a unique form of systemic EMC infection. EMC were documented within the splenic &amp; renal tissues with remarkable activation of melanomacrophage centers (MMC) denoting the pathophysiological response of hematopoietic tissues to the EMC invasion. The current study sheds light on the growing danger of aquatic pollution and its direct trigger of zoonotic metacercarial spread through the consumption of infected fish flesh.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103159"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145006450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anisakis infection induces IgE responses resulting from ILC2 and Th2 cell activation via IL-33 in the murine stomach","authors":"Shinya Hidano ,&nbsp;Kazuhiro Mizukami ,&nbsp;Kohei Shirakami ,&nbsp;Hideyuki Ito ,&nbsp;Kazunori Matsumura ,&nbsp;Astri Dewayani ,&nbsp;Sotaro Ozaka ,&nbsp;Benjawan Saechue ,&nbsp;Shimpei Ariki ,&nbsp;Takashi Ozaki ,&nbsp;Kaori Noguchi ,&nbsp;Yomei Kagoshima ,&nbsp;Spanuch Ekronarongchai ,&nbsp;Masaaki Okamoto ,&nbsp;Naganori Kamiyama ,&nbsp;Nozomi Sachi ,&nbsp;Takashi Sekiya ,&nbsp;Satoshi Takaki ,&nbsp;Kazunari Murakami ,&nbsp;Takashi Kobayashi","doi":"10.1016/j.parint.2025.103184","DOIUrl":"10.1016/j.parint.2025.103184","url":null,"abstract":"<div><div><em>Anisakis simplex</em>, a parasitic nematode transmitted through the consumption of raw or undercooked seafood, is known to cause gastric anisakidosis, often accompanied by acute inflammatory and allergic responses. However, the underlying immunological mechanisms remain poorly understood. In this study, we established a murine model by orally infecting BALB/c mice with live <em>Anisakis</em> larvae to elucidate the host immune response. Repeated infection with live <em>Anisakis</em> larvae, but not with homogenates, induced severe gastric inflammation, accompanied by a marked elevation of total IgE, <em>Anisakis</em>-specific IgE, Ani s 1-specific IgE, and interleukin (IL)-5 in the serum. Active cutaneous anaphylaxis confirmed the presence of functional <em>Anisakis</em>-specific IgE capable of mediating immediate hypersensitivity. Flow cytometry of gastric lamina propria cells showed increased infiltration of IL-5 producing group 2 innate lymphoid cells (ILC2s), eosinophils, IL-4 producing T helper (Th) cells and B cells in mice with repeated infection. Furthermore, immunohistochemistry revealed widespread localization of IL-33-positive cells in the gastric mucosa, consistent with the observed increased levels of truncated IL-33 and total IL-33. These findings suggest that <em>Anisakis</em> infection induces a type 2 immune response through IL-33-driven activation of ILC2s followed by Th2 development, thereby promoting eosinophilia and antigen-specific IgE. This model enables new insights of <em>Anisakis</em>-associated allergic inflammation and may serve as future therapeutic studies.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103184"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145308741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to First report of Saccocoelioides nanii (Digenea: Haploporidae) infecting an extremophile host, Jenynsia sulfurica (Cyprinodontiformes: Anablepidae) Parasitology International, Volume 110 (2026), 103148","authors":"Macarena S. De Martino ,&nbsp;Guillermo E. Teran ,&nbsp;Patricia M.C. Romero ,&nbsp;Felipe Alonso ,&nbsp;Melisa Moncada ,&nbsp;German Reig Cardarella ,&nbsp;Gaston Aguilera ,&nbsp;Martin M. Montes","doi":"10.1016/j.parint.2025.103163","DOIUrl":"10.1016/j.parint.2025.103163","url":null,"abstract":"","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103163"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Notoedres cati-induced bilateral erythemato-ceruminous otitis externa in a cat","authors":"Lorena-Eliza Mastan ,&nbsp;Andrada-Silvia Cârstolovean ,&nbsp;Lavinia-Alexandra Lipan ,&nbsp;Ligia-Rebeca Muntean ,&nbsp;Ioana-Mădălina Moraru ,&nbsp;Aurora-Livia Ursache ,&nbsp;Bogdan Sevastre ,&nbsp;Viorica Mircean","doi":"10.1016/j.parint.2025.103168","DOIUrl":"10.1016/j.parint.2025.103168","url":null,"abstract":"<div><div>Notoedric mange, caused by <em>Notoedres cati</em> (<em>N. cati</em>), is a rare but severe parasitic skin disease primarily affecting stray cats, with zoonotic potential. This case report describes a one-year-old intact male European Shorthair presented with extensive cervico-facial skin lesions and systemic illness signs. Clinical examination revealed severe pruritus, alopecia, thick crusts, bilateral erythemato-ceruminous otitis externa and deep pyoderma, with the maximum severity score on the clinical mange scale. Complementary tests confirmed <em>N. cati</em> infestation through skin scrapings and ear wax examination, alongside concurrent <em>Toxocara cati</em>, <em>Dipylidium</em> spp., and <em>Giardia duodenalis</em> infections. Hematological findings indicated a systemic inflammatory response. Treatment comprised topical and systemic antiparasitics (esafoxolaner, praziquantel, eprinomectin and fenbendazole), oral antibiotics (cephalexin), antipruritic therapy (prednisolone), and supportive skin care. Follow-up examinations at days 8, 12, 15, and 21 demonstrated progressive clinical improvement, with resolution of mange, endoparasitic infections, otitis, and deep pyoderma by the end of treatment. This case highlights the need for early recognition and comprehensive management of notoedric mange, particularly in stray feline populations. The observed association between <em>N. cati</em> infestation and otitis externa suggests that its role in feline ear disease may be underestimated.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103168"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neospora caninum, Sarcocystis spp. and Toxoplasma gondii infections and their relationship with milk production in goats from Argentina","authors":"K.D. Steffen ,&nbsp;L. Gortari Castillo ,&nbsp;M.L. Gos ,&nbsp;M.C. Venturini ,&nbsp;R.O. Arias ,&nbsp;G. Moré","doi":"10.1016/j.parint.2025.103165","DOIUrl":"10.1016/j.parint.2025.103165","url":null,"abstract":"<div><div>The apicomplexan protozoa <em>Neospora caninum, Sarcocystis</em> spp. and <em>Toxoplasma gondii</em> are worldwide distributed. Goat infections with these protozoans are frequent, although the relationship with milk production is unknown. The aim of this study was to evaluate and relate the antibodies titers to <em>N. caninum</em>, <em>Sarcocystis</em> spp. and <em>T. gondii</em> with the goat milk production. The study was conducted in two commercial dairy goat farms located in the province of Buenos Aires, Argentina. A total of 336 Saanen breed goats were evaluated (146 goats of E1 and 190 goats of E2). The total production per lactation was calculated and adjusted to 240 lactation days in milliliters. Blood samples obtained and the age, number of lactations, body condition, and FAMACHA© degree were recorded. Sera were tested for <em>N. caninum</em>, <em>Sarcocystis</em> spp. and <em>T. gondii</em> antibodies by IFAT, starting at 1:100 for <em>N. caninum</em> and <em>T. gondii</em> IFATs, and at 1:50 for <em>Sarcocystis</em> spp., and all three IFATs from each animal were processed at the same time to final titer. The overall seroprevalence of <em>N. caninum, Sarcocystis</em> spp. and <em>T. gondii</em> was 81.8 % (275/336), 85.1 % (286/336) and 66.7 % (224/336), respectively. Forty-nine percent (164/336) of goats were seropositive to three IFATs, 37.5 % (126/336) to two and 12.2 % (41/336) to only one. Similar <em>N. caninum</em> and <em>Sarcocystis</em> spp. seroprevalences were observed in E1 (80.1 and 88.4 %) compared to E2 (83.1 and 82.6 %), respectively. A higher <em>T. gondii</em> seroprevalence was detected in E1 (80.1 %) than E2 (56.3 %). A small group of 16 goats with higher IFAT titers to <em>T. gondii</em>, produced significantly less milk (85.3 L) than the rest. No significant milk productivity differences were found in goats seropositive and negative to only one, two or all three IFATs when analyzed within age and/or ordinal lactation number groups. Our results indicate a low association of seropositivity to these protozoans with goat milk production.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103165"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145016091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-neurosurgical meningitis by Naegleria fowleri and Staphylococcus aureus in Ecuador: A case report","authors":"Eduardo Montalvo ,&nbsp;Camila Lara-Cazorla ,&nbsp;V. Neira ,&nbsp;Eder Cano-Pérez ,&nbsp;M. Páez ,&nbsp;Byron Fuertes-Flores ,&nbsp;Tatiana Guevara-Bahamonde ,&nbsp;Gabriela Echeverría-Garcés ,&nbsp;E. Castro-Lalangui ,&nbsp;E. Rivadeneira ,&nbsp;Diego Álvarez Pico ,&nbsp;Nery Giler Zambrano ,&nbsp;Génesis García-Díaz","doi":"10.1016/j.parint.2025.103179","DOIUrl":"10.1016/j.parint.2025.103179","url":null,"abstract":"<div><div>This report describes the first documented case in Ecuador of primary amoebic meningoencephalitis caused by <em>Naegleria fowleri</em>, in coinfection with methicillin-resistant <em>Staphylococcus aureus</em> (MRSA) associated with a ventriculoperitoneal shunt (VPS). A 23-year-old male with a history of severe traumatic brain injury developed central nervous system infection symptoms after VPS placement. Despite targeted antibiotics for MRSA, clinical deterioration continued. Whole genome sequencing confirmed <em>N. fowleri</em>, prompting antiparasitic treatment with amphotericin B and fluconazole, resulting in partial improvement. This case underscores the need to consider rare pathogens in atypical neurological cases and highlights the diagnostic value of genome sequencing in complex infections.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103179"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145252228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observation of Giardia duodenalis infection in Mongolian gerbils: Cysts isolated from bovine feces","authors":"Yifei Li ,&nbsp;Hongsen Yu ,&nbsp;Xiaolin Zeng ,&nbsp;Tianyu Li ,&nbsp;Xuhai Li ,&nbsp;Ting Wu ,&nbsp;Xiangyu Yan ,&nbsp;Qixi Li ,&nbsp;Chenhan Bu ,&nbsp;Qi Sun ,&nbsp;Jingjing Wang ,&nbsp;Ershun Zhou ,&nbsp;Zhengtao Yang","doi":"10.1016/j.parint.2025.103151","DOIUrl":"10.1016/j.parint.2025.103151","url":null,"abstract":"<div><div>Assemblage E of <em>Giardia duodenalis</em>, primarily infecting ruminants, has been relatively understudied both in vivo and in vitro. Due to unsuccessful attempts at in vitro cultivation, this study focused on establishing an economical, stable, and clinically relevant experimental animal model for Assemblage E infections. Cysts were purified from bovine feces via 33 % zinc sulfate flotation, with Assemblage E identity confirmed by gdh gene sequencing. Nine five – day - old Mongolian gerbils were randomly allocated into control group (PBS), low-dose group (5 × 10⁴cysts), and high-dose group (1 × 10⁵cysts) averagely, Gerbils were received bovine-derived Assemblage E cysts via oral gavage, all infected subjects were undergone of necropsy at 8 days post-infection. Longitudinal monitoring result demonstrated that gerbils in infected groups exhibited growth retardation and excreted soft feces compared with controls. Histopathological examination result revealed that massive trophozoite were colonized on atrophied duodenal villi, meanwhile, enterocyte boundary was effacement in high-dose group. Scanning electron microscopy (SEM) detection result were showed that the trophozoite density decline along the intestinal tract: duodenum&gt;jejunum&gt;ileum. That could be confirmed the characteristic of trophozoite duodenal tropism. Encystation dynamics analysis was identified bile acid-mediated morphological transformation in the ileum through SEM, the process of encystation with trophozoite rounding, ventral disc degeneration and cyst wall formation. These results could recapitulate the complete life cycle of Assemblage E in experimental hosts, this study provided a validated model for investigating host-specific about giardiasis pathogenesis.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"111 ","pages":"Article 103151"},"PeriodicalIF":1.9,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145005054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}