Preliminary evaluation of the protective effects of recombinant AMA1 and IMP1 against Eimeria stiedae infection in rabbits.

BACKGROUND: Eimeria stiedae parasitizes the bile duct, causing hepatic coccidiosis in rabbits. Coccidiosis control using anticoccidials led to drug resistance and residues; therefore, vaccines are required as an alternative control strategy. Apical membrane antigen 1 (AMA1) and immune mapped protein 1 (IMP1) are surface-located proteins that might contribute to host cell invasion, having potential as candidate vaccine antigens. METHODS: Herein, we cloned and expressed the E. stiedae EsAMA1 and EsIMP1 genes. The reactogenicity of recombinant AMA1 (rEsAMA1) and IMP1 (rEsIMP1) proteins were investigated using immunoblotting. For the vaccination-infection trial, rabbits were vaccinated with rEsAMA1 and rEsIMP1 (both 100 µg/rabbit) twice at 2-week intervals. After vaccination, various serum cytokines were measured. The protective effects of rEsAMA1 and rEsIMP1 against E. stiedae infection were assessed using several indicators. Sera were collected weekly to detect the specific antibody levels. RESULTS: Both rEsAMA1 and rEsIMP1 showed strong reactogenicity. Rabbits vaccinated with rEsAMA1 and rEsIMP1 displayed significantly increased serum IL-2 (F (4, 25) = 9.53, P = 0.000), IL-4 (F (4, 25) = 7.81, P = 0.000), IL-17 (F (4, 25) = 8.55, P = 0.000), and IFN-γ (F (4, 25) = 6.89, P = 0.001) levels; in the rEsIMP1 group, serum TGF-ß1 level was also elevated (F (4, 25) = 3.01, P = 0.037). After vaccination, the specific antibody levels increased and were maintained at a high level. The vaccination-infection trial showed that compared with the positive control groups, rabbits vaccinated with the recombinant proteins showed significantly reduced oocyst output (F (5, 54) = 187.87, P = 0.000), liver index (F (5, 54) = 37.52, P = 0.000), and feed conversion ratio; body weight gain was significantly improved (F (5, 54) = 28.82, P = 0.000). CONCLUSIONS: rEsAMA1 and rEsIMP1 could induce cellular and humoral immunity, protecting against E. stiedae infection. Thus, rEsAMA1 and rEsIMP1 are potential vaccine candidates against E. stiedae.

Feline platynosomiasis in Klang Valley, Malaysia: Diagnosis, pathology and management.

Platynosomum fastosum (synonym Platynosomum concinnum, Platynosomum illiciens ) is a hepatic fluke causing platynosomiasis or 'lizard poisoning' in cats. This disease is generally being underestimated by veterinary practitioners due to lack of awareness and difficulty in diagnosis although the severe cases of platynosomiasis could be fatal. This study was designed to detect the presence of cat liver fluke through faecal examination among cats kept in shelters, pet cats and stray cats around Klang Valley, Malaysia. The detection of liver flukes among stray cats was based on post-mortem examination. A total of 201 faecal samples were collected from eight shelters (n = 119) and five veterinary clinics (n = 82) in Klang Valley were subjected to simple floatation and formalin-ether sedimentation techniques for ova detection. P. fastosum ova were identified in three faecal samples obtained from shelters (2.52%) and three samples collected from veterinary clinics (3.66%) by faecal examination. A total of 51 stray cats were procured from Pest and Animal Control Unit of the respective municipality. The cats were euthanised and necropsied to collect liver samples and bile duct. The liver was then dissected for isolation and identification of the fluke and bile duct fluid were aspirated for detection of fluke ova. Twelve cats (23.5%) were positive for P. fastosum and ova were found in their bile. Macroscopically, affected cats showed mottled liver (33.3%), distended gall bladder with thick tenacious bile (66.7%) that microscopically exhibited hepatic steatosis (25.0%) and hepatitis (33.3%). The severity of parasite load was almost equally distributed between the positive cats with low (n = 5, 55.6%; > 125 adult fluke) and high parasite burden (n = 4, 44.4%; < 125 adult fluke) cats, respectively. This study revealed the detection of P. fastosum among pet, shelters and stray cats in Klang Valley, Malaysia.

Prospects for liver fluke vaccines.

Fasciola spp., Opisthorchis spp. and Clonorchis sinensis are common liver flukes that can cause a variety of diseases, mainly cholangiocarcinoma induced by clonorchiasis and liver damage and associated pathology induced by fascioliasis. Because these trematodes are parasites of humans and domestic animals, they have greatly affected the economy of agricultural industries and public health worldwide. Due to the emergence of drug resistance and the living habits of flukes, among other reasons, a possibility of reinfection remains even when antiparasitic drugs are used. Therefore, developing a safe, efficient and cost-effective vaccine against trematodes is an important goal. Here, we briefly describe the progress in the development of vaccines against liver flukes. Related innovations may provide effective protection against these helminths and the diseases that they cause.

Differential Effect of Antioxidants Glutathione and Vitamin C on the Hepatic Injuries Induced by Plasmodium berghei ANKA Infection.

Malaria is a life-threatening disease caused by Plasmodium and represents one of the main public health problems in the world. Among alterations associated with the disease, we highlight the hepatic impairment resulting from the generation of oxidative stress. Studies demonstrate that liver injuries caused by Plasmodium infection are associated with unbalance of the antioxidant system in hepatocytes, although little is known about the role of antioxidant molecules such as glutathione and vitamin C in the evolution of the disease and in the liver injury. To evaluate disease complications, murine models emerge as a valuable tool due to their similarities between the infectious species for human and mice. Herein, the aim of this study is to evaluate the effect of antioxidants glutathione and vitamin C on the evolution of murine malaria and in the liver damage caused by Plasmodium berghei ANKA infection. Mice were inoculated with parasitized erythrocytes and treated with glutathione and vitamin C, separately, both at 8 mg/kg during 7 consecutive days. Our data showed that during Plasmodium infection, treatment with glutathione promoted significant decrease in the survival of infected mice, accelerating the disease severity. However, treatment with vitamin C promoted an improvement in the clinical outcomes and prolonged the survival curve of infected animals. We also showed that glutathione promoted increase in the parasitemia rate of Plasmodium-infected animals, although treatment with vitamin C has induced significant decrease in parasitemia rates. Furthermore, histological analysis and enzyme biochemical measurement showed that treatment with glutathione exacerbates liver damage while treatment with vitamin C mitigates the hepatic injury induced by the infection. In summary, the current study provided evidences that antioxidant molecules could differently modulate the outcome of malaria disease; while glutathione aggravated the disease outcome and liver injury, the treatment with vitamin C protects the liver from damage and the evolution of the condition.

G6pd-Deficient Mice Are Protected From Experimental Cerebral Malaria and Liver Injury by Suppressing Proinflammatory Response in the Early Stage of Plasmodium berghei Infection.

Epidemiological studies provide compelling evidence that glucose-6-phosphate dehydrogenase (G6PD) deficiency individuals are relatively protected against Plasmodium parasite infection. However, the animal model studies on this subject are lacking. Plus, the underlying mechanism in vivo is poorly known. In this study, we used a G6pd-deficient mice infected with the rodent parasite Plasmodium berghei (P.berghei) to set up a malaria model in mice. We analyzed the pathological progression of experimental cerebral malaria (ECM) and acute liver injury in mice with different G6pd activity infected with P.berghei. We performed dual RNA-seq for host-parasite transcriptomics and validated the changes of proinflammatory response in the murine model. G6pd-deficient mice exhibited a survival advantage, less severe ECM and mild liver injury compared to the wild type mice. Analysis based on dual RNA-seq suggests that G6pd-deficient mice are protected from ECM and acute liver injury were related to proinflammatory responses. Th1 differentiation and dendritic cell maturation in the liver and spleen were inhibited in G6pd-deficient mice. The levels of proinflammatory cytokines were reduced, chemokines and vascular adhesion molecules in the brain were significantly down-regulated, these led to decreased cerebral microvascular obstruction in G6pd-deficient mice. We generated the result that G6pd-deficiency mediated protection against ECM and acute liver injury were driven by the regulatory proinflammatory responses. Furthermore, bioinformatics analyses showed that P.berghei might occur ribosome loss in G6pd-deficient mice. Our findings provide a novel perspective of the underlying mechanism of G6PD deficiency mediated protection against malaria in vivo.

Capillaria hepatica (syn. Calodium hepaticum) as a Cause of Asymptomatic Liver Mass.

Capillaria hepatica (syn. Calodium hepaticum) is a parasitic nematode of rodents, rarely infecting humans. An asymptomatic Israeli adult male with extensive travel history was diagnosed with a liver mass on routine post-thymectomy follow-up. Imaging and computer tomography (CT) guided biopsy were inconclusive. Surgical excision revealed an eosinophilic granuloma with fragments of a nematode suspected to be C. hepatica. Molecular methods verified the diagnosis, and the patient was treated empirically. This is the first case of hepatic capillariasis described in Israel, and the first to be diagnosed using molecular methods.

Bioengineered Liver Cell Models of Hepatotropic Infections.

Hepatitis viruses and liver-stage malaria are within the liver infections causing higher morbidity and mortality rates worldwide. The highly restricted tropism of the major human hepatotropic pathogens-namely, the human hepatitis B and C viruses and the Plasmodium falciparum and Plasmodium vivax parasites-has hampered the development of disease models. These models are crucial for uncovering the molecular mechanisms underlying the biology of infection and governing host-pathogen interaction, as well as for fostering drug development. Bioengineered cell models better recapitulate the human liver microenvironment and extend hepatocyte viability and phenotype in vitro, when compared with conventional two-dimensional cell models. In this article, we review the bioengineering tools employed in the development of hepatic cell models for studying infection, with an emphasis on 3D cell culture strategies, and discuss how those tools contributed to the level of recapitulation attained in the different model layouts. Examples of host-pathogen interactions uncovered by engineered liver models and their usefulness in drug development are also presented. Finally, we address the current bottlenecks, trends, and prospect toward cell models' reliability, robustness, and reproducibility.

Diagnosis and clinical management of hepatosplenic schistosomiasis: A scoping review of the literature.

BACKGROUND: Hepatosplenic schistosomiasis (HSS) is a disease caused by chronic infection with Schistosma spp. parasites residing in the mesenteric plexus; portal hypertension causing gastrointestinal bleeding is the most dangerous complication of this condition. HSS requires complex clinical management, but no specific guidelines exist. We aimed to provide a comprehensive picture of consolidated findings and knowledge gaps on the diagnosis and treatment of HSS. METHODOLOGY/PRINCIPAL FINDINGS: We reviewed relevant original publications including patients with HSS with no coinfections, published in the past 40 years, identified through MEDLINE and EMBASE databases. Treatment with praziquantel and HSS-associated pulmonary hypertension were not investigated. Of the included 60 publications, 13 focused on diagnostic aspects, 45 on therapeutic aspects, and 2 on both aspects. Results were summarized using effect direction plots. The most common diagnostic approaches to stratify patients based on the risk of variceal bleeding included the use of ultrasonography and platelet counts; on the contrary, evaluation and use of noninvasive tools to guide the choice of therapeutic interventions are lacking. Publications on therapeutic aspects included treatment with beta-blockers, local management of esophageal varices, surgical procedures, and transjugular intrahepatic portosystemic shunt. Overall, treatment approaches and measured outcomes were heterogeneous, and data on interventions for primary prevention of gastrointestinal bleeding and on the long-term follow-up after interventions were lacking. CONCLUSIONS: Most interventions have been developed on the basis of individual groups' experiences and almost never rigorously compared; furthermore, there is a lack of data regarding which parameters can guide the choice of intervention. These results highlight a dramatic need for the implementation of rigorous prospective studies with long-term follow-up in different settings to fill such fundamental gaps, still present for a disease affecting millions of patients worldwide.

Parasites of the liver - epidemiology, diagnosis and clinical management in the European context.

Parasites in the liver cause significant global morbidity and mortality, as they can lead to recurrent cholangitis, cirrhosis, liver failure and cancer. Due to climate change and globalisation, their incidence is increasing, especially in Europe. The correct diagnosis of a hepatic parasite is often delayed because clinicians are unfamiliar with respective entities. Therefore, in this review, we aim to provide clinicians with a comprehensive clinical picture of hepatic parasites and to bring these neglected parasitic liver diseases to the wider attention of hepatology stakeholders in Europe and around the world.

Evaluation of Schistosomiasis Mansoni Morbidity by Hepatic and Splenic Elastography.

In patients with Mansoni schistosomiasis, it is fundamental to evaluate the disease morbidity, which is reflected by the severity of periportal fibrosis (PPF) and parameters of portal hypertension, as analyzed by ultrasonography (US). This study aimed to evaluate the morbidity of schistosomiasis by hepatic and splenic point shear-wave elastography (pSWE) and relate this to US parameters. The PPF pattern, the diameter of the portal and splenic veins and the size of the spleen were evaluated by US. Then, liver and spleen pSWEs were assessed in 74 patients using the same equipment. As the PPF pattern progressed, the splenic pSWE values significantly increased. Significant correlations between splenic pSWE, the longitudinal and transverse lengths of the spleen and the diameters of the portal and splenic veins were observed. These findings, however, were not observed through hepatic pSWE. In conclusion, the splenic pSWE has the potential for assessing morbidity in schistosomiasis mansoni.

Hepatic Capillaria hepatica (Bancroft, 1893) infection in cat (Felis catus)-histopathological findings and first report from Iran.

Capillaria hepatica (syn. Calodium hepaticum) is a globally distributed nematode with a high affinity to the liver of a wide range of mammalian hosts, including humans. Documented reports of the nematode in cats and associated histopathology are rare. Here, we describe a case of C. hepatica infection in a 5-year-old male stray cat from Iran. At post-car accident necropsy, all body parts appeared normal except for the liver, in which a few yellowish-white granulomatous nodules were observed through the capsule and in the organ. Histopathological examination of the tissue revealed a large number of clustered parasite eggs in the parenchyma. The barrel-shaped, un-embryonated eggs (55.19 × 28.37 µm), with inconspicuous caps at both ends, were covered with striated shells. The presence of ova in the liver tissue had resulted in the development of hepatic inflammation with hepatocellular necrosis associated with the development of multifocal granulomas. As predators of small rodents, the cats might have a significant role in the epidemiology of C. hepatica. Infection of hosts through ingestion of embryonated eggs in contaminated water, food, or soil is of major importance in the epidemiology of C. hepatica. Since the rare reports of feline infection have come mainly from accidental detection of the parasite, any hepatic disease presenting difficulties to find an etiological agent may virtually be associated with the infection with this little-known nematode.

γδ T cells in malaria: a double-edged sword.

Malaria remains a devastating global health problem, resulting in many annual deaths due to the complications of severe malaria. However, in endemic regions, individuals can acquire 'clinical immunity' to malaria, characterized by a decrease in severe malaria episodes and an increase of asymptomatic Plasmodium falciparum infections. Recently, it has been reported that tolerance to 'clinical malaria' and reduced disease severity correlates with a decrease in the numbers of circulating Vγ9Vδ2 T cells, the major subset of γδ T cells in the human peripheral blood. This is particularly interesting as this population typically undergoes dramatic expansions during acute Plasmodium infections and was previously shown to play antiparasitic functions. Thus, regulated γδ T-cell responses may be critical to balance immune protection with severe pathology, particularly as both seem to rely on the same pro-inflammatory cytokines, most notably TNF and IFN-γ. This has been clearly demonstrated in mouse models of experimental cerebral malaria (ECM) based on Plasmodium berghei ANKA infection. Furthermore, our recent studies suggest that the natural course of Plasmodium infection, mimicked in mice through mosquito bite or sporozoite inoculation, includes a major pathogenic component in ECM that depends on γδ T cells and IFN-γ production in the asymptomatic liver stage, where parasite virulence is seemingly set and determines pathology in the subsequent blood stage. Here, we discuss these and other recent advances in our understanding of the complex-protective versus pathogenic-functions of γδ T cells in malaria.

Positive consequences of splenectomy for patients with schistosomiasis-induced variceal bleeding.

BACKGROUND: Patients with hepatic schistosomiasis are at high risk of gastroesophageal variceal bleeding, which is highly torrential and life threatening. This study aimed to assess the effects of splenectomy on patients with schistosomiasis-induced variceal bleeding, especially those influences related to overall survival (OS) rate. METHODS: From January 2005 to December 2018, 112 patients with schistosomiasis-induced varices were enrolled. In that period, all the patients with hepatic schistosomiasis who received endoscopic treatment for primary and secondary prophylaxis of gastroesophageal variceal bleeding were found eligible. The patients were divided into splenectomized group (n = 44, 39.3%) and control group (n = 68, 60.7%). RESULTS: Multivariate regression analysis of OS showed that splenectomy, hepatic carcinoma, and times of endoscopic treatment were independent prognostic factors for OS. Kaplan-Meier analysis revealed that the 5-year OS rate was 82.7% in splenectomized group versus 53.2% in control group (P = 0.037). The rate of no recurrence of variceal bleeding during 5-year (56.8% vs. 47.7%, P = 0.449) indicated that there was no significant difference between the two groups. Patients who received splenectomy had increased risk of portal vein thrombosis (52.3% vs. 29.4%, P = 0.012) and decreased proportion of severe ascites (20.5% vs 50.0%, P = 0.002). CONCLUSION: Splenectomy prior to endoscopic treatment provides a superior long-term survival for patients with schistosomiasis-induced variceal bleeding.

Synergistic effects of cagA+ Helicobacter pylori co-infected with Opisthorchis viverrini on hepatobiliary pathology in hamsters.

Human liver fluke infection caused by Opisthorchis viverrini is associated with several biliary diseases including cholangiocarcinoma (CCA). Recently, it was discovered that the liver fluke is a reservoir of Helicobacter pylori, particularly the cagA-positive strain (cytotoxin-associated gene A) in its gut. Given that two carcinogenic pathogens are associated with CCA development, however, the role of cagA-positive H. pylori in opisthorchiasis has not been clarified. The present study was therefore aimed to investigate histopathological changes of the biliary system in hamsters co-infected with O. viverrini and cagA-positive H. pylori or O. viverrini and cagA-negative H. pylori, with controls of O. viverrini, cagA-positive H. pylori, or cagA-negative H. pylori alone, over time. Major histopathological changes were systematically investigated. All pathological features were quantified/semi-quantified and compared among the experimental groups. The results showed that O. viverrini infection groups (O. viverrini, cagA-positive H. pylori and cagA-negative H. pylori) showed a high degree of eosinophil and mononuclear cell infiltration, lymphoid aggregation and granuloma. Specifically, O. viverrini co-infected with cagA-positive H. pylori presented significantly higher inflammatory scores than O. viverrini and O. viverrini with cagA-positive H. pylori. Proliferation and adaptive lesions such as hyperplasia, goblet cell metaplasia and dysplasia were detected only in O. viverrini infection groups. Dysplasia, the precancerous lesion of CCA, was observed in the first-order bile ducts, especially where the inflammation existed and was found earlier and more severely in O. viverrini with cagA-positive H. pylori than other groups. Similarly, the BrdU (bromodeoxyuridine) proliferation index was significantly higher in O. viverrini co-infected with cagA-positive H. pylori than O. viverrini and O. viverrini with cagA-negative H. pylori groups. Periductal fibrosis was a prominent histopathologic feature in chronic infection in O. viverrini infection groups. Multiple logistic regression showed that O. viverrini co-infected with cagA-positive H. pylori and the duration of infection were the most important factors associated with periductal fibrosis (OR 3.02, 95% CI 1.02-9.29, p = 0.04 and OR 3.82, 95% CI 2.61-5.97, p<0.001). This study demonstrates that the liver fluke co-infected with cagA-positive H. pylori induces severe biliary pathology that may predispose to cholangiocarcinogenesis.

The visceral larva migrans caused by Toxocara canis: a case report.

Hepatic toxocarosis is caused by the dog´s roundworm, Toxocara canis. Responsible for an eosinophilic inflammatory syndrome causing liver damage that can be detected on ultrasound, computed tomography and sometimes magnetic resonance imaging. We report the case of a nine-year-old child, living in countryside, with a notion of cohabitation with canids. He presented a digestive symptomatology revealed by abdominal pain, with a hemeosinophilia in the hemogram. The etiological assessment of hyper eosinophilia objectified a positive Toxocara canisserology. The imaging assessment in search of digestive visceral lesions, found multiple heterogeneous hypoechogenic areas, poorly defined, scattered in the liver. On the abdominal CT scan, its areas appear of unenhanced density and low density and better visible after injection of contrast product. This observation reveals that imagery, although not very specific, helps in the assessment of liver damage from digestive toxocarosis.

Prophylactic versus therapeutic role of the transplanted CD34+ Umbilical Cord Blood Stem Cells and Wharton Jelly Mesenchymal Stem Cells in early / acute hepatic S. mansoni granulomas reversal in mice; a novel approach.

PURPOSE: Praziquantel (PZQ) is the conventional antibilharzial agent. Nevertheless, no antibilharzial prophylactic agents or 100% curable therapy approved and no reported data about use of human CD34+ Umbilical Cord Blood Stem Cells (CD34+UCBSCs) or Wharton Jelly Mesenchymal Stem Cells (WJMSCs) in prevention and/or complete eradication of acute S.mansoni granulomas in liver. We aimed to study possible prophylactic vs therapeutic role of human CD34+UCBSCs and WJMSCs in acute hepatic bilharzial granulomas in pre vs post-infected mice. METHODS: Seventy mice were divided into 7 groups (10 mice each): Normal, S.mansoni-infected, post-infected PZQ-treated, CD34+UCBSCs pre and post-infected, WJMSCs pre and post-infected. Serological, parasitological, histopathological evaluation using OCT4 & TGFB immunohistochemistry and quantitative image analysis assessment of TGFB-stained fibrogenesis in liver granulomas performed. RESULTS: Histopathologically, surprisingly and significantly, the prophylactic pre-infection stem cells (CD34+UCBSCs and WJMSCs) & similarly the post-infection CD34+UCBSCs treatment revealed eradication/reversal of the entire granulomas and no fibrosis. Moreover, post-infection PZQ treatment showed fewer and significantly smaller granulomas than post-infection WJMSCs treatment. Nevertheless, post-infection WJMSCs exhibited non-significant less TGFB-stained fibrogenesis. CONCLUSION: CD34+UCBSCs exerted the best prophylactic and therapeutic roles in prevention and complete cure of acute hepatic S.mansoni granulomas over WJMSCs and PZQ. In contrast, only pre-infection WJMSCs exhibited similar preventive (prophylactic) effect. On the contrary, post-infection WJMSCs were the worst (incompletely reversed granulomas). Post-infection Praziquantel was overall better therapeutically than WJMSCs in this regard. Accordingly, when it comes to WJMSCs application, WJMSCs are better used as a pre-infection prophylactic and preventive tool rather than a post-infection therapy. Further studies are needed.

Liver fluke infections by Amphimerus sp. (Digenea: Opisthorchiidae) in definitive and fish intermediate hosts in Manabí province, Ecuador.

Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabí in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections. We developed a cross-sectional study in three communities at Pedro Pablo Gómez parish in the province of Manabí, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gómez, Manabí, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.

Change in schistosomiasis-related liver disease with repeated praziquantel treatment in school children in rural Zambia.

Repeated praziquantel treatment for schistosomiasis is an effective method to reduce disease burden. Ultrasonographic methods were used to assess the severity of schistosoma mansoni-related liver disease and demonstrate improvement following treatment. We compared data from 733 children in 2010 and 972 children in 2018 to determine the effect of repeated praziquantel treatment on prevalence of liver disease. Three age groups were compared across three liver disease classifications (normal, mild, severe). From 2010 to 2018, there was a significant reduction in prevalence of severe liver disease in all age groups (P = 0.03 for 5-10 years, P < 0.001 for 11-15 years and 16-20 years). In both male and female students, the proportion having a normal liver significantly increased (P < 0.001) from 2010 to 2018, in the 11-15-year-olds and 16-20-year-olds, demonstrating that liver disease significantly reduced in these age groups. This study demonstrates a reduction in schistosomiasis-related morbidity with repeated praziquantel treatment.