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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. [ABSTRACT FROM AUTHOR]

Background Human opisthorchiasis, caused by Opisthorchis viverrini , is a public health problem in Southeast Asia and a major risk factor for cholangiocarcinoma. In Lao PDR, seroprevalence and the relationship between the number of O. viverrini eggs in infected people and specific antibody responses are still unknown. We evaluated and compared parasitological and serological screening methods in the community in an endemic area of opisthorchiasis in Lao PDR. Methods Seroprevalence of O. viverrini -specific total IgG and IgG4 antibodies and their relationships with O. viverrini egg intensities were evaluated in Khammouane Province, central Lao PDR, using ELISA and a modified formalin ethyl-acetate concentration technique (FECT). Results FECT stool examination revealed O. viverrini eggs in 70.3% (90/128) of individuals (95% CI 61.6 to 78.1%) while ELISA (based on total IgG and on IgG4 antibodies to O. viverrini) found 98.4% (95% CI 94.5 to 99.8%) and 89.8% (95% CI 83.3 to 94.5%) of sera, respectively. There was a positive and significant correlation between numbers of O. viverrini eggs per gram and levels of both IgG (R2=0.168, p<0.001) and IgG4 (R2=0.219, p<0.001) antibodies. Conclusions A high prevalence of human opisthorchiasis in Lao PDR was found using a new platform, serological screening in the community. This points to a need for sustainable control of this liver fluke infection. [ABSTRACT FROM AUTHOR]

Chronic infections of humans with Opisthorchis viverrini and Clonorchis sinensis spanning decades may lead to life-threatening pathology prior to cholangiocarcinoma (CCA), which usually has a poor prognosis. Serological tools can support the parasitological examination in clinical diagnosis and support screening for risk of CCA. We developed novel immunochromatographic test kits using a soluble, somatic tissue extract of adult O. viverrini worms as an antigen and colloidal gold-labeled conjugates of IgG and IgG4 antibodies, and evaluated the diagnostic values of both the OvSO-IgG and OvSO-IgG4 kits. For diagnosis of human opisthorchiasis individually, the diagnostic sensitivity, specificity, and positive and negative predictive values with 95% confidence intervals in the OvSO-IgG kit were 86.6% (78.9–92.3), 89.5% (84.2–93.5), 82.9% (74.8–89.2), and 91.9% (87.0–95.4), respectively, while the 75% (65.9–82.7), 98.4% (95.5–99.7), 96.6% (90.3–99.3), and 87% (81.7–91.2), respectively, for the OvSO-IgG4 kit at the prevalence of infection of 37.1%. Twenty-three (76.7%) and 14 (46.7%) of 30 clonorchiasis sera showed positive reactivity with the OvSO-IgG and OvSO-IgG4 kits, respectively. There was 84.1% (κ-value = 0.649) concordance between the two kits, which was statistically significant (p < 0.001). Both ICT kits can be employed as quick and easy point-of-care diagnostic tools, and hence, the OvSO-IgG and OvSO-IgG4 kits can support expanded capacity for clinical diagnosis of human opisthorchiasis and clonorchiasis. These kits may find utility in large-scale surveys in endemic areas where there are limited sophisticated medical facilities or capacity. [ABSTRACT FROM AUTHOR]

Opisthorchis -like metacercariae were found in cyprinoid fish, Puntius brevis , bought from markets in the Bago region, Central Myanmar. Adult worms recovered from experimentally-infected hamsters resembled Opisthorchis viverrini . DNA was extracted from adults and metacercariae. A portion of the mitochondrial cytochrome c oxidase subunit 1 ( cox 1) and the internal transcribed spacer 2 (ITS2) regions were amplified using the polymerase chain reaction and then sequenced. The sequences confirmed that the flukes were O. viverrini. In phylogenetic analyses, sequences of O. viverrini , including our new sequences, clustered in a group with high bootstrap support for ITS2 (80%) and the cox 1 gene (99%). Interestingly, ITS2 and cox 1 sequences of O. viverrini and O. lobatus were very similar, raising a question about the identity of the latter. This is the first report of O. viverrini in cyprinoid fish in Central Myanmar, and only the second report of the species in Myanmar. It is an urgent warning against consuming raw or semi-cooked freshwater fish dishes. Development of an effective food-safety strategy should be provided for the prevention and control of opisthorchiasis and other foodborne diseases. [ABSTRACT FROM AUTHOR]

Opisthorchis viverrini is endemic in the South East Asian region, especially in Cambodia, Lao People's Democratic Republic, Vietnam and Thailand, but there have been no previous records from Myanmar. During stool surveys of rural populations in three regions of Lower Myanmar, Opisthorchis-like eggs were found in 34 out of 364 (9.3%) participants by stool microscopy after using the modified formalin-ether concentration technique. DNA was extracted from these positive stool samples and a portion of the mitochondrial cytochrome c oxidase subunit I (cox1) gene was amplified using the polymerase chain reaction and then sequenced. DNA sequences, successfully obtained from 18 of 34 positive samples (Bago Region, n = 13; Mon State, n = 3; Yangon Region, n = 2), confirmed that the eggs were of O. viverrini. Sequences showed 99.7% identity with O. viverrini mitochondrial cox1 (GenBank accession no. JF739555) but 95%, 88.7%, 82.6% and 81.4% identities with those of Opisthorchis lobatus from Lao People's Democratic Republic (GenBank accession nos. HQ328539-HQ328541), Metorchis orientalis from China (KT239342), Clonorchis sinensis from China (JF729303) and Opisthorchis felineus from Russia (EU921260), respectively. When alignement with other Opisthorchiidae trematodes, 81% similarity with Metorchis bilis from Czech Republic (GenBank accession nos. KT740966, KT740969, KT740970) and Slovakia (GenBank accession nos. KT740971-KT740973), 84.6% similarity with Metorchis xanthosomus from Czech Republic (GenBank accession no. KT740974), 78.6% similarity with M. xanthosomus from Poland (GenBank accession no. KT740968) and 82.2% similarity with Euamphimerus pancreaticus from Czech Republic (GenBank accession no. KT740975) were revealed. This study demonstrated, for the first time, O. viverrini from rural people in Myanmar using molecular methods and is an urgent call for surveillance and control activities against opisthorchiasis in Myanmar. [ABSTRACT FROM AUTHOR]

Opisthorchis viverrini, a human liver fluke, is highly prevalent in Southeast Asia. Definitive diagnosis of infection is usually achieved parasitologically through the discovery of fluke eggs in feces. However, the eggs of O. viverrini are difficult to differentiate morphologically from those of other minute intestinal flukes in fecal samples, even for experienced technicians. The present study developed a label-free optical methodology for analysis of O. viverrini eggs using Raman spectroscopy. Raman features of O. viverrini eggs were reported that can be used as marker bands for the efficient analysis of O. viverrini eggs in fecal specimens. The methodology presented here allows for the rapid detection of O. viverrini egg infection and can be readily and practicably applied in any clinical setting, even those in which a trained parasitologist is not available. [ABSTRACT FROM AUTHOR]

• Opisthorchis viverrini, one of three helminths classified as group 1 biological carcinogens • Rapid detection of anti–O. viverrini IgG antibodies in patients with cholangiocarcinoma • Anti–O. viverrini IgG antibody titre higher in sera of cholangiocarcinoma than other cancers • Diagnostic biomarker to predict risk of O. viverrini–associated cholangiocarcinoma • Reduce the costs of screening tools toward the planning for prevention of disease Opisthorchiasis is caused by an infection with fish-borne liver flukes of the genus Opisthorchis. Opisthorchiasis frequently leads to chronic inflammation in the biliary tract and is classified as a group 1 biological carcinogen by the International Agency for Research on Cancer: a definitive risk for cholangiocarcinoma (CCA). We used the rapid immunochromatographic test (ICT) to detect anti- Opisthorchis viverrini IgG and IgG4 subclass antibodies in sera of patients with CCA. The ICT kits were developed based on soluble antigens excreted and secreted by O. viverrini adult worms. ICT indicated sera was positive for IgG and IgG4 antibodies, respectively, in 22 (61.1%) and 15 (41.6%) participants of the 36 study participants diagnosed with CCA (P > 0.05). Our study also included groups with other cancers and with liver cirrhosis, where the IgG ICT and IgG4 ICT kits were 27.7% (13/47) and 25.5% (12/47) positive, respectively (P > 0.05). Neither total the IgG ICT nor the IgG4 ICT yielded positive results in a control group of 20 healthy participants. Moreover, the percentage positivity rate using the ICT for total IgG between the CCA group and the other cancers and liver cirrhosis group was significantly different (P < 0.05). By contrast, no significant difference between these groups was apparent in the ICT for IgG4 antibody. The CCA group was 6.53 times more likely to have positive anti– O. viverrini IgG antibody (odds ratio 6.53, P < 0.001) and 3.27 times more likely to have positive anti– O. viverrini IgG4 antibody (odds ratio 3.27, P = 0.010) than the non-CCA group. This information is of potential value for the development of a diagnostic biomarker to predict risk for O. viverrini infection-associated CCA. [ABSTRACT FROM AUTHOR]