Fasciolopsis Research Articles

Fasciolopsis buski isolated from human host, India has distinct clade based on nuclear ribosomal DNA sequences.

Fasciolopsiasis caused by Fasciolopsis buski, is a significant cause of morbidity. In the present study F. buski detected during endoscopy of a 50-year-old male patient form Uttar Pradesh, India was used for phylogenetic analysis based on 28S rDNA and ITS2 region. The parasite was genetically similar to an isolate in pig from Meghalaya. The intra-species genetic variation for 28S rDNA was 1-3% (India), 5% (Vietnam) and for ITS2, 1- 2% (India) while 17% from Vietnam. Thus, F. buski from humans or pigs from India were closely related than those from Vietnam and China which were grouped into separate clades.

Western Anthelmintics in Early Twentieth-Century China Colonial Practices and Knowledge on "Tropical Diseases" of the In/between.

Protestant (medical) missionaries were the main proponents of Western medicine in China after the Opium Wars. Several studies have highlighted how they used spectacular surgery as a means of gaining public trust. As well as surgery, they also administered anthelmintic drugs such as santonin as a tool of persuasion and conversion. Many anthelmintic drugs of the European materia medica had a colonial history. My paper analyses how coloniality materialised in medical practice and anthelmintics in China. For the late nineteenth century, I will examine the colonial practices in which the drug santonin was involved. At the time, santonin was the drug of choice for treating roundworm. In the early twentieth century, medical missionaries became involved in parasitological research on parasitic worms such as hookworm and Fasciolopsis buski. For this period, I will explore how new knowledge about anthelmintics emerged in the scattered knowledge space of China, and how it related to colonialism and imperialism.

Gastrointestinal Helminthic Infection among the Population in Northern Thailand.

Gastrointestinal (GI) helminthic infections pose substantial public health threat, particularly in northern Thailand, with a heightened concern in Nan province. This study aims to evaluate the prevalence of GI helminthic infections in Nan province and identify associated risk factors in local population. A cross-sectional survey was conducted in 2022. Fecal specimens were collected and examined using Kato-Katz technique and Formalin Ethyl-Acetate Concentration Technique (FECT). Univariate analysis employed the Chi-square test to explore correlations, while logistic regression was defined risk factors associated with parasite infections. Among 739 individuals surveyed, 14.34% were revealed GI helminthic infections. Notably, infection rates were higher in males (20.40%) compared to females (8.95%), with a notable prevalence among individuals aged ≥ 60 (17.78%) and high infection rate was demonstrated in Kiew Chan village (21.67%). The most commonly detected helminths were minute intestinal flukes (MIFs) (10.01%) and Capillaria spp. (3.11%). Males were significantly associated with GI helminthic infections, while individuals aged 40-49 and aged 50-59 commonly displayed of parasite infections. Additionally, Kiew Chan village exhibited a significant association with GI helminthic infections, followed by Sop Puen village. Furthermore, fecal specimens of 13 rodent specimens were frequency revealed Strongyloides spp. (92.30%) and mostly exposed Ancylostoma caninum (41.93%) among 93 canines. These findings highlight the imperative for immediate public health interventions in Nan province and analogous areas in northern Thailand. Implementing strategies to enhance sanitation infrastructure and promote hygiene education can significantly contribute for reducing the prevalence of GI helminthic infections and improve overall community health.

Unveiling the Transmission Potential of Opisthorchis viverrini and Intestinal Helminths Along the Thailand-Laos Border in Thailand.

In pursuit of enhancing prevention efforts for the notably high endemic Opisthorchis viverrini infection in lower Mekong sub-region countries, particularly Thailand and Laos, this cross-sectional study investigated the transmission potential of O. viverrini and other intestinal helminths along the Thailand-Laos border in seven Thai villages. Human and pet faecal samples, Bithynia snails and cyprinid fish were analysed for helminth infections. Additionally, a questionnaire survey assessed relevant risk factors among the human population. Two groups of helminth infections were detected in humans: foodborne infections (FBIs) including O. viverrini, minute intestinal flukes (MIFs), and Taenia spp., and soil-transmitted infections (STIs) including hookworm and Strongyloides stercoralis, with prevalence rates of 7.4%, 0.5%, 2.5%, 0.5%, 2.5% and 3%, respectively. Smoking was identified as a risk factor for O. viverrini infection [adjusted odds ratios (ORa) = 3.12, 95% confidence intervals (CI): 1.33-7.30, p = 0.009] and FBIs (ORa = 2.47, 95% CI: 1.14-5.33, p = 0.022), while male was a risk factor for FBIs (ORa = 2.62, 95% CI: 1.16-5.94, p = 0.021). In dogs, hookworm, Toxocara spp., Spirometra mansoni, Trichuris vulpis and Hymenolepis diminuta were identified with prevalence rates of 35.6%, 8.1%, 8.1%, 1.2% and 1.2%, respectively. In cats, hookworm, Toxocara spp., S. mansoni, Strongyloides spp., Platynosomum fastosum, MIFs and H. diminuta were identified with prevalence rates of 50%, 17.9%, 10.7%, 7.1%, 3.6%, 3.6% and 3.6%, respectively. Bithynia snails showed 2% virgulate and 0.7% unknown cercariae infections, while among 19 cyprinid fish species, only unknown metacercariae were found. Our findings underscore the necessity of an integrated approach following the One Health concept to effectively combat these parasitic diseases while addressing human, animal and environmental health.

Discrete measurements of RNA polymerase and reverse transcriptase fidelity reveal evolutionary tuning.

Direct methods for determining the fidelity of DNA polymerases are robust, with relatively little sample manipulation before sequencing. In contrast, methods for measuring RNA polymerase and reverse transcriptase fidelities are complicated by additional preparation steps that introduce ambiguity and error. Here, we describe a sequencing method, termed Roll-Seq, for simultaneously determining the individual fidelities of RNA polymerases and reverse transcriptases (RT) using Pacific Biosciences single molecule real-time sequencing. By using reverse transcriptases with high rolling-circle activity, Roll-Seq generates long concatemeric cDNA from a circular RNA template. To discern the origin of a mutation, errors are recorded and determined to occur within a single concatemer (reverse transcriptase error) or all concatemers (RNA polymerase error) over the cDNA strand. We used Roll-Seq to measure the fidelities of T7 RNA polymerases, a Group II intron-encoded RT (Induro), and two LINE RTs (Fasciolopsis buski R2-RT and human LINE-1). Substitution rates for Induro and R2-RT are the same for cDNA and second-strand synthesis while LINE-1 has 2.5-fold lower fidelity when performing second-strand synthesis. Deletion and insertion rates increase for all RTs during second-strand synthesis. In addition, we find that a structured RNA template impacts fidelity for both RNA polymerase and RT. The accuracy and precision of Roll-Seq enable this method to be applied as a complementary analysis to structural and mechanistic characterization of RNA polymerases and reverse transcriptases or as a screening method for RNAP and RT fidelity.

Misclassification of Opisthorchis viverrini and Minute Intestinal Fluke Eggs by Routine Laboratory Staff Using Images from the Kato-Katz Method.

The Kato-Katz method is a commonly used diagnostic tool for helminth infections, particularly in field studies. This method can yield inaccurate results when samples contain eggs that are similar in appearance, such as Minute Intestinal Fluke (MIF) and Opisthorchis viverrini (OV) eggs. The close resemblance of eggs can be problematic and raises the possibility of false diagnoses. The objectives were to compare the diagnostic performance of the Kato-Katz method for accurately identifying MIF and OV and to provide evidence of possible misclassification. Methods: Based on questionnaire responses from 15 (young parasitologists and public health staff), the test comprised 50 MIF egg images and 50 OV egg images, for a total of 100 Google Form questionnaires. The morphology of MIF and OV eggs found size and shape similarity and found that the shoulder rims were small, while the OV egg found the knobs had disappeared. The opercular conjunction was apparent, the shoulder rims and miricidium were prominent. The average percentage of correctly classified infections was 61.6 ± 12.1%. The accuracy percentages for both public health staff and young parasitologists in identifying were found to be 59.0 ± 14.8 and 66.8 ± 2.8, respectively. There was no significant difference observed in both groups. These findings highlight the need for improving the accuracy of parasite identification. Preserving stool samples before the Kato-Katz method can help mitigate the potential degradation or distortion of parasite eggs. The incorrect classification of both eggs had an impact on treatment plans and the policy of parasite control programs.

Assessment of the genetic diversity of lymnaeid (Gastropoda: Pulmonata) snails and their infection status with trematode cercariae in different regions of Thailand

Lymnaeid snails are some of the most widespread snails and are the first intermediate host of trematode parasites that affect human and livestock health. A full understanding of the genetic relationship of hosts and parasites is of paramount importance for effective parasite management. The present study assessed the prevalence of trematode larvae in lymnaeid snails and examined the genetic diversity of these snails collected across Thailand. We collected 672 lymnaeid snails from 39 locations in 22 provinces of six regions in Thailand. Subsequently, cercarial infection in the snails was observed by using the shedding method. Lymnaeid snails released 5 types of trematode cercariae, namely, xiphidiocercariae, echinostome cercariae I, echinostome cercariae II, furcocercous cercariae, and strigea cercariae. The phylogenetic analysis based on ITS2 and 28S rDNA sequences revealed 5 cercaria types assigned to four trematode families, of which two belong to the group of human intestinal flukes. Combination of shell morphology and sequence analysis of the mitochondrial COI and 16S rDNA genes, the lymnaeid snails were classified into two species, Radix rubiginosa and Orientogalba viridis. Moreover, the combined dataset of mtDNA genes (COI + 16S rDNA) from R. rubiginosa and O. viridis revealed 32 and 15 different haplotypes, respectively, of which only a few haplotypes were infected with cercariae. The genetic diversity and genetic structure revealed that R. rubiginosa and O. viridis experienced a bottleneck phenomenon, and showed limited gene flow between populations. Population demographic history analyses revealed that R. rubiginosa and O. viridis experienced population reductions followed by recent population expansion. These findings may improve our understanding of parasite–lymnaeid evolutionary relationships, as well as the underlying molecular genetic basis, which is information that can be used for further effective control of the spread of trematode disease.

Ov-RPA-CRISPR/Cas12a assay for the detection of Opisthorchis viverrini infection in field-collected human feces.

Opisthorchis viverrini infection is traditionally diagnosed using the Kato-Katz method and formalin ethyl-acetate concentration technique. However, the limited sensitivity and specificity of these techniques have prompted the exploration of various molecular approaches, such as conventional polymerase chain reaction (PCR) and real-time PCR, to detect O.viverrini infection. Recently, a novel technique known as recombinase polymerase amplification (RPA)-clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) (RPA-CRISPR/Cas) assay was developed as a point-of-care tool for the detection of various pathogens, including viruses and bacteria such as severe acute respiratory syndrome coronavirus 2 and Mycobacterium tuberculosis. This technology has demonstrated high sensitivity and specificity. Therefore, we developed and used the RPA-CRISPR/Cas assay to detect O.viverrini infection in field-collected human feces. To detect O.viverrini infection in fecal samples, we developed a CRISPR/Cas12a (RNA-guided endonuclease) system combined with RPA (Ov-RPA-CRISPR/Cas12a). Several fecal samples, both helminth-positive and helminth-negative, were used for the development and optimization of amplification conditions, CRISPR/Cas detection conditions, detection limits, and specificity of the RPA-CRISPR/Cas12a assay for detecting O.viverrini infection. The detection results were determined using a real-time PCR system based on fluorescence values. Additionally, as the reporter was labeled with fluorescein, the detection results were visually inspected using an ultraviolet (UV) transilluminator. A receiver operating characteristic curve (ROC) was used to determine the optimal cutoff value for fluorescence detection. The diagnostic performance, including sensitivity and specificity, of the Ov-RPA-CRISPR/Cas12a assay was evaluated on the basis of comparison with standard methods. The Ov-RPA-CRISPR/Cas12a assay exhibited high specificity for detecting O.viverrini DNA. On the basis of the detection limit, the assay could detect O.viverrini DNA at concentrations as low as 10-1ng using the real-time PCR system. However, in this method, visual inspection under UV light required a minimum concentration of 1ng. To validate the Ov-RPA-CRISPR/Cas12a assay, 121 field-collected fecal samples were analyzed. Microscopic examination revealed that 29 samples were positive for O.viverrini-like eggs. Of these, 18 were confirmed as true positives on the basis of the Ov-RPA-CRISPR/Cas12a assay and microscopic examination, whereas 11 samples were determined as positive solely via microscopic examination, indicating the possibility of other minute intestinal fluke infections. The Ov-RPA-CRISPR/Cas12a assay developed in this study can successfully detect O.viverrini infection in field-collected feces. Due to the high specificity of the assay reported in this study, it can be used as an alternative approach to confirm O.viverrini infection, marking an initial step in the development of point-of-care diagnosis.

Effectiveness of health education in improving knowledge, attitude and practice related to foodborne zoonotic trematodes in Vietnam, with a particular focus on Clonorchis sinensis.

Foodborne zoonotic trematodes (FZT), which infect the liver, lungs and intestines of humans, are an emerging public health concern in tropical countries including Vietnam. In northern Vietnam, Clonorchis sinensis is recognised as the most important species of the FZT. Up to now, small-scale studies conducted in the country have indicated that health education could improve participants' knowledge and practices related to clonorchiasis, however strong evidence is still lacking. We conducted an intervention trial between 2020 and 2021 in four communes in Yen Bai and Thanh Hoa province, aiming to evaluate the impact of an extended educational package on knowledge, attitude and practices related to clonorchiasis, as well as on knowledge on the large liver fluke and minute intestinal flukes. To this end, baseline and post-intervention questionnaires were conducted. Generalised estimating equations models were run to analyse the impact of the intervention on knowledge, attitudes and practices over time in the intervention versus control group. Finally, 172 people in the intervention group and 162 in the control group were included for analysis. Results demonstrated that the intervention significantly improved clonorchiasis knowledge, attitudes and practices, with higher odds for a correct knowledge response (odds ratio (OR) = 2.80, 95% confidence interval (CI) = 1.84-4.27, p-value < 0.001), increased average mean attitude score (mean = 0.363, 95%CI = 0.182-0.544, p-value < 0.001), and a reduced odds of consuming raw fish (OR = 0.15, 95%CI = 0.06-0.40, p = 0.002) in the intervention group compared to the control group post-intervention versus baseline. Additionally, participants in the intervention group exhibited enhanced basic knowledge of the large liver fluke and minute intestinal flukes post-intervention. These findings demonstrate the potential of health education programs in preventing clonorchiasis in endemic areas, emphasising the importance of continued health education as a critical component of integrated control programs for clonorchiasis.

Environmental influence on abundance and infection patterns of snail intermediate hosts of liver and intestinal flukes in North and Central Vietnam.

Liver and intestinal flukes (LIF) are important groups of foodborne zoonotic trematodes (FZTs) in Southeast Asia, including Vietnam. Their complex life cycles require specific freshwater snail species as the obligatory first intermediate hosts. In 2019, we conducted a longitudinal study in Yen Bai and Thanh Hoa provinces in North and Central Vietnam, respectively, to investigate the diversity of LIF and their infection prevalence in relation to snail host abundance and environmental factors. Using a combination of morphological and molecular identification techniques, we identified 10 LIF species infecting 11 snail host species. We observed significant seasonal variation in the mean abundance of several snail host species, with the majority of snails collected during the spring. We also detected seasonal changes in LIF species composition, with the highest species richness reported in the spring. Clonorchis sinensis and Fasciola gigantica, two medically important human liver flukes in Asia, were found only in the spring in Yen Bai. Our study revealed that not all snail host species have the same probability of becoming infected, and we recorded seasonal variations in the prevalence of LIF infection in different snail species in relation to water parameters.

Phylogenetic relationship of Prohemistomum vivax to other trematodes based on the internal transcribed spacer region and mitochondrial genes.

Prohemistomum vivax is a zoonotic small cyathocotylid trematode that inhabits the intestines of fish-eating birds and mammals. Here, we amplified the internal transcribed spacer (ITS) sequence and six mitochondrial protein-coding genes (PCGs) from P. vivax. The ITS region was 1389 base pairs long and had a partial 18S ribosomal RNA gene, a full ITS1, 5.8S rRNA, and ITS2 sequence, and a partial 28S rRNA gene. The ITS region of P. vivax showed a minimum pairwise distance (0.3-0.6%) from the ITS sequences of Cyathocotylidae sp. 1 and 2 metacercariae from Clarias gariepinus. This result suggests that these metacercariae belong to P. vivax metacercariae. We first amplified mitochondrial genes from P. vivax, including cytochrome c oxidase subunit III (cox3) partial sequence; tRNA-His, cytochrome b (cytb), and NADH dehydrogenase subunit 4L (nad4L) complete sequences; and NADH dehydrogenase subunit 4 (nad4), cytochrome c oxidase I (cox1), and NADH dehydrogenase subunit 5 (nad5) partial sequences. P. vivax was most closely related to Cyathocotyle prussica (NC_039780) and Holostephanus sp. (OP082179), with cox1, cox3, and cytb genes conserved among the three trematodes. The ML phylogenetic tree of ITS sequences supports the order Diplostomida, divided into two main clades (the superfamily Diplostomoidea and Schistosomatoidea). The phylogeny of concatenated amino acid sequences of P. vivax six PCGs revealed that diplostomoids and Clinostomum sp. evolved in a clade with Plagiorchiida members, away from Schistosoma species. These results may yield ribosomal and mitochondrial genetic markers for molecular epidemiological investigations of cyathocotylid intestinal flukes.

An Approach for Egg Parasite Classification Based on Ensemble Deep Learning

Opisthorchis viverrini and minute intestinal fluke (MIF) infections are heavily epidemic in northeastern Thailand. Their primary cause is eating raw or undercooked cyprinid fishes, and they cause health problems in the human digestive system. In cases of liver fluke, these parasites can go through the bile duct system, which may cause cholangiocarcinoma (bile duct cancer). When a medical doctor suspects that a patient is infected with parasites, they typically request a stool analysis to determine the type of egg parasites using microscopy. Both parasites have similar characteristics, thus, it is necessary for a specialist to identify the specific type of egg parasites present. Many automatic systems have been developed using deep learning to assist doctors in diagnosing the type of egg parasite. In this study, we proposed three models of deep learning architectures and created voting ensembles to analyze egg parasite images. Images of similar liver fluke eggs and MIF eggs were taken from the Parasitology Laboratory, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand. Image data augmentation is used to expand images from different perspectives and assist the system in acquiring a greater variety of images. Three models performed effectively, by employing the hard voting ensemble, the accuracy increased to 86.67%, while for the second group, the accuracies reached 68.00%, 76.00%, and 77.33%, respectively. Using the soft voting ensemble, the accuracy improved to 79.33%. These outcomes highlight the potential of ensemble deep learning in image classification. Furthermore, these results align closely with those achieved by several experts in image classification. Hence, a promising ensemble approach can aid doctors in accurately classifying images of egg parasites.

Prevalence of Foodborne Trematodes in Small Indigenous Fish Species in Local Markets of Phnom Penh, Cambodia.

Background: This study aimed to determine the prevalence and mean infection intensity of zoonotic foodborne trematodes (FBT) in small indigenous species (SIS) fish hosts. Materials and Methods: A total of 8630 specimens of unknown origin were collected from the markets in Phnom Penh City. Fish were identified, weighed, and separated into 20 g subsamples for each fish species, and were examined using the artificial digestion method. A total of 10 species of FBT were detected in 11 species of fish out of the 23 species of fish in the total sample. Results: All infected FBT species were intestinal flukes. No liver flukes were found. The overall prevalence of FBT infection was 29.3% ± 5.3%, and the mean intensity was 0.85 ± 1.89 metacercariae (Mc)/g. The highest FBT prevalence was observed for Isthmiophora hortensis (10.7%) and Centrocestus formosanus (7.9%). Other species identified were Diplostomum spp., Echinochasmus japonicus, Echinostoma revolutum, Echinostoma sudanense, Haplorchis taichui, Haplorchis pumilio Heterophyes spp., and Procerovum varium. The highest mean intensity was found for Diplostomum spp. (1.75 ± 3.03 Mc/g). Trichopsis vittata was one of the main species constituting the SIS in urban markets (31.72%) and showed the highest prevalence of FBT (75.0%). In addition, T. vittata had the highest diversity of intestinal flukes compared with other fish species. Amblypharyngodon chulabhornae showed the highest mean intensity. but low diversity (only two species) and low prevalence. Conclusions: T. vittata could be considered a potential indicator for targeted monitoring of FBT intestinal flukes, but A. chulabhornae could also be considered for quantitative studies considering its high mean intensity.

FISH BORNE TREMATODE INFECTION IN THAC BA LAKE – NORTHERN VIETNAM: HYPERENDEMIC ISSUE AND VARIETY ASOCIATED RISK FACTORS.

A cross sectional survey was conducted in three communes including An Phucommune of Luc Yen district, and Bao Ai and Mong Son communes in Yen Binh districtnear by Thac Ba lake of Yen Bai Province in August and September, 2019 to investigatethe FZTs (liver fluke C. sinensis and intestinal flukes included H. pumilio, H. taichui, H.yokogawai, Procerovum varium and C. formosanus) infection status in the area and todetermine the associated risk factors of the diseases using Formaline ether concentrationtechnique and interview by questionnaire.1214 individuals with an average age of 41 years old were involved in the presentstudy, among the participants, 47.5% were infected with FBT. By univariate analysis, thefactors were at the most significant risk of getting infected were persons who were men,ate raw fish, prepared raw dish with fish from the lake, drank whisky with raw dish, livedin Luc Yen District, lived next to the lake (&lt; 500 m from house to the lake, and their age(age of 20 – 39); breeding dog &amp; cat, feeding dog &amp; cat with raw fish were associated tothe FBT as well. There was no relationship between house characteristics (having hygienelatrine or fish pond) and FBT infection.Identification of recovered trematodes: 757 adult flukes were expelled from 6 willingpatients (R2=0.803) in the two districts, of which 20 flukes were randomly selected forcarmine stain. All stained flukes were identified as C. sinensis by the most typicalmorphology traits: the tandem and dendritic testes overlap the caeca laterally and site inthe posterior third of the body.We need conduct a prevention and control program at the Thac Ba lake for not onlyhuman but also animal cat, dog, fish and snail asap.

High endemicity of Opisthorchis viverrini infection among people in northern Cambodia confirmed by adult worm expulsion

Opisthorchis viverrini infection is an emerging disease in Cambodia, especially in central and southeastern areas. However, its status in northern areas bordering Lao PDR has been relatively unknown. The present study was performed to investigate the status of O. viverrini infection among people in Preah Vihear and Stung Treng provinces through fecal examination to detect eggs and recovery of adult flukes from some of the egg-positive cases. Fecal examinations were performed on a total of 1101 people from 10 villages in the 2 provinces using the Kato-Katz thick smear technique. For recovery of adult flukes and other helminth parasites 10 volunteers positive for eggs of Opisthorchis viverrini and/or minute intestinal flukes (Ov/MIF), in Kampong Sangkae village, Preah Vihear province, were administered a single oral dose of 40 mg/kg praziquantel plus 5–10 mg/kg of pyrantel pamoate and purged with 40–50 g magnesium salts. Adult trematodes, together with nematodes and cestodes expelled in diarrheic stools were collected under a stereomicroscope or with the naked eye. The proportion of egg-positive cases for overall liver and intestinal helminths was high but not notably different between the 2 provinces, 65.5% in Preah Vihear versus 64.7% in Stung Treng. The average proportion of Ov/MIF egg-positive cases was 59.8%. A total of 315 adult specimens of O. viverrini were recovered from the 10 volunteers (4–98 specimens per individual; mean, 32). A smaller number of Haplorchis taichui adults, an intestinal fluke, were found mixed-infected in 7 (103 specimens in total; 1–31 per individual; mean, 15) of the 10 volunteers. Adult specimens of hookworms, Enterobius vermicularis, Trichostrongylus sp., and a Taenia tapeworm strobila were recovered in some cases. Based on the results, it has been confirmed that the surveyed areas in Preah Vihear and Stung Treng provinces, Cambodia, are highly endemic areas of O. viverrini infection with a low-grade mixed infection with H. taichui.

The complete mitochondrial genome of Ogmocotyle ailuri: gene content, composition and rearrangement and phylogenetic implications.

Trematodes of the genus Ogmocotyle are intestinal flukes that can infect a variety of definitive hosts, resulting in significant economic losses worldwide. However, there are few studies on molecular data of these trematodes. In this study, the mitochondrial (mt) genome of Ogmocotyle ailuri isolated from red panda (Ailurus fulgens) was determined and compared with those from Pronocephalata to investigate the mt genome content, genetic distance, gene rearrangements and phylogeny. The complete mt genome of O. ailuri is a typical closed circular molecule of 14 642 base pairs, comprising 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. All genes are transcribed in the same direction. In addition, 23 intergenic spacers and 2 locations with gene overlaps were determined. Sequence identities and sliding window analysis indicated that cox1 is the most conserved gene among 12 PCGs in O. ailuri mt genome. The sequenced mt genomes of the 48 Plagiorchiida trematodes showed 5 types of gene arrangement based on all mt genome genes, with the gene arrangement of O. ailuri being type I. Phylogenetic analysis using concatenated amino acid sequences of 12 PCGs revealed that O. ailuri was closer to Ogmocotyle sikae than to Notocotylus intestinalis. These data enhance the Ogmocotyle mt genome database and provide molecular resources for further studies of Pronocephalata taxonomy, population genetics and systematics.

Type of cercaria in freshwater snails at Tunggu Pampang Reservoir, Makassar City, Indonesia

The Tunggu Pampang Reservoir is one of the reservoirs located in the city of Makassar. The functions of the reservoir area was tourist attractions and fish farming locations so that the local community uses them for swimming, fishing, selling, and gardening. The existence of various types of freshwater snails in the reservoir has the potential to act as intermediate hosts for trematodes in animals and humans. This study aimed to analyze the type of cercariae in freshwater snails. This research is a descriptive survey to determine the distribution of trematode larvae. The stages of this research began with the snails were collected from Tunggu Pampang Reservoir, Makassar City. Freshwater snails were collected at several points in the reservoir. Freswater snail collection using hand collecting method. The snails were put into a plastic bag with different types of snails and site of collection. The collected samples and cercariae were examined in the Tropical Disease Laboratory of the Study Program of DIII Medical Laboratory Technology, Megarezky University, South Sulawesi, Indonesia. Freshwater snails are placed on a petri dish and their shells were gently crushed with a stamper. Dropped with aquadest on the crushed snail shell. The next step was observed using a microscope to determine the presence of cercariae. Cercariae found then identified according to morphological classification as previously study. A total number of 500 freshwater snail were collected in Tunggu Pampang Reservoir. The results showed that overall snails infected with cercariae was 33,4%. The highest prevalence of cercariae in Indoplanorbis exustus was 94.3%. Total of Echinostoma cercariae found (n = 224) compared to furcocercous cercariae (n = 5). Cercariae of Echinostoma sp., Fasciola gigantica, Fasciolopsis buski living in Tungu Pampang Reservoir can cause diseases in humans and animals. Larval trematodes can be controlled in snails using reducing parasite contamination, monitoring surveillance, information dissemination, and preventive education.

Differentiating paramphistome species in cattle using DNA barcoding coupled with high-resolution melting analysis (Bar-HRM).

Paramphistomosis is caused by paramphistome or amphistome parasites, including Fischoederius elongatus, Gastrothylax crumenifer, Orthocoelium parvipapillatum, and Paramphistomum epiclitum. The control and prevention of these parasite outbreaks are difficult because of the wide occurrence of these species. Besides, the clinical manifestations and their egg characteristics are similar to those of other intestinal flukes in the paramphistome group, leading to misdiagnosis. Here, we employed DNA barcoding using NADH dehydrogenase (ubiquinone, alpha 1) (ND1) and cytochrome c oxidase subunit I (COI), coupled with high-resolution melting analysis (Bar-HRM), for species differentiation. As a result, ParND1_3 and ParCOI4 resulted in positive amplification in the paramphistomes and Fasciola gigantica, with significantly different melting curves for each species. The melting temperatures of each species obtained clearly differed. Regarding sensitivity, the limit of detection (LoD) for all species of paramphistomes was 1pg/µl. Our findings suggest that Bar-HRM using ParND1_3 is highly suitable for the differentiation of paramphistome species. This approach can be used in parasite detection and epidemiological studies in cattle.

Prevalence of Pathogenic Intestinal Parasites and Enteropathogenic Bacteria in Faecal Samples Obtained from Abattoirs in Ogbomoso, Oyo State, Nigeria

This study was undertaken to determine the prevalence of intestinal parasites and enteropathogenic bacteria in fecal effluents from abattoir. A total of 162 samples were examined out of which 70 faecal samples were collected from cow, 35 from pig, 35 from goat and 22 from sheep. These samples were processed using standard parasitological techniques ( macroscopy, microscopy; the Formol-ether concentration technique and zinc sulphate floatation technique) and bacteriological (culture, Gram reaction and biochemical characterization). Data was analyzed using Chi-square test. One hundred and eleven (111) samples were found positive with one or more parasites giving an overall prevalence of 68.5%. Pigs recorded the highest prevalence of 77.1% for intestinal parasites, followed by goat and cow with prevalence of 68.6% and 65.7% respectively and the least prevalence was observed in sheep, 63.6%. The prevalence of different parasites encountered include Fasciolopsis buski (8.6%), Hookworm (8.0%), Ascaris suum (7.4%), Balantidium coli (7.4%), Fasciola hepatica (7.4%), Entamoeba histolytica (7.4%), Taenia species (6.2%), Fasciola gigantica (4.3%) and Toxocara species (1.2%). Mixed infections of Balantidium coli+Entamoeba histolytica has the highest frequency of 4(2.5%) followed by Entamoeba histolytica+Hookworm and Toxocara species+Balantidium coli with the frequency of 3(1.9%) each, Ascaris suum+Taenia species, Ascaris suum+Taenia species+Hookworm and Balantidium coli+Fasciola hepatica with a frequency of 2(1.2%) each and Toxocara species+Balantidium coli recorded the lowest frequency of 1(0.6%). Also the prevalence of potentially pathogenic bacteria and yeast cells encountered include Bacillus species (29.6%), Escherichia coli (23.5%), Campylobacter species (17.3%), Pseudomonas aeruginosa (11.1%), Staphylococcus aureus (10.5%), Yeast cells (4.9%) and Staphylococcus species (3.1%). This study shows high degrees of fecal contamination of intestinal parasites and bacterial agents. As a result of this sanitary measures and Government policy should be strictly employed as this will go a long way to help check environmental contamination and reduce potential risks posed by these pathogens.

Genetic distance and phylogenetic relationships of some Echinostoma species (E. malayanum, E. revolutum, E. miyagawai) and Hypoderaeum conoideum (family Echinostomatidae) inferred from partial 28S rDNA sequence analysis

Echinostomiasis is a neglected disease caused by the intestinal flukes (family Echinostomatidae, suborder Echinostomata) and is common in communities in Asian countries, such as India, Indonesia, the Philippines, China, Malaysia, Singapore, Korea, Japan, Thailand, Laos, Cambodia and Vietnam. The genetic markers from the nuclear ribosomal transcription units are commonly used in genetic studies and phylogenetic analyses. A portion of the 28S rDNA sequence (domains D1–D3, of 1062–1067 bp for the final use) was obtained from the zoonotic Echinostoma malayanum (strain E/Amala-EMI3-TH), E. revolutum (strain Erevo-MSD15-TH), E. miyagawai (Emiya-RED11-TH), and Hypoderaeum conoideum (Hcono-RED42-TH) species; and used to perform an alignment for genetic distance estimation and phylogenetic analysis. The alignment was performed using 62 strains of 42 species from 19 genera of the family Echinostomatidae, including Echinoparyphium, Echinostoma, Artyfechinostomum, Patagifer, Neoacanthoparyphium, Hypoderaeum, Echinoparyphium, Drepanocephalus, Euparyphium, Chaunocephalus, Neopetasiger, Ribeiroia, Cathaemasia, Rhopalias, Isthmiophora, Petasiger, Moliniella, Pegosomum, and Schistosoma (family Schistosomatidae). The genetic distance estimation among 16 strains/10 species has shown a low intra-specific divergence level between strains within the same species, such as E. miyagawai (0–0.10%), E. revolutum (0.10–0.50%), and H. conoideum (0–0.10%), while between strains within the same genus it was higher (normally over 1.0%) and among strains/species between genera it was the highest (3.06–4.12%). The 28S rDNA sequence analysis and phylogenetic relationship well supported the Echinostoma/ Artyfechinostomum malayanum intergeneric taxonomy and the topology indicated clear, well-supported positions of member species in different genera in the family Echinostomatidae of the suborder Echinostomata. More sensu lato samples of the genera, are required for sequencing, particularly those of zoonotic species in the five genera: Artyfechinostomum, Echinostoma, Hypoderaeum, Echinoparyphium, and Isthmiophora. The resultant mitochondrial and nuclear data obtained from these species will be a good source to use to clearly assess the taxonomic and generic relationships.