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

AIMS: 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. METHODS AND RESULTS: 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. CONCLUSIONS: 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.

Investigation of Plasma Cell-Free DNA and MiRNA in Cholangiocarcinoma and Opisthorchiasis Viverrini Patients.

OBJECTIVES: This study aimed to assess the diagnostic potential of cell-free DNA (cfDNA) and cell-free miRNA (cf-miRNA) for distinguishing between Healthy, asymptomatic opisthorchiasis viverrini and cholangiocarcinoma in a preliminary manner. METHODS: In this study, 36 participants were enrolled into three health status groups: a healthy control group (HC), Opisthorchis viverrini-infected group (OV), and a cholangiocarcinoma group (CCA), each comprising 12 participants. Concentration measurements of cfDNA and cf-miRNA from plasma were conducted. Additionally, ultra-low-pass whole-genome sequencing (ULP-WGS) was employed to investigate DNA alterations. RESULTS: The study revealed a significant elevation in plasma cfDNA concentration in the cholangiocarcinoma (CCA) group compared to healthy controls (HC) and Opisthorchis viverrini-infected (OV) groups (P < 0.001). The cfDNA concentration demonstrated a sensitivity of 75.00% and specificity of 95.83% for differentiating cholangiocarcinoma, with a cut-off of > 30.50 ng/ml plasma. Likewise, the concentration of cf-miRNA in the CCA group significantly differed from that in the HC and OV groups, demonstrating a sensitivity of 83.33% and specificity of 95.83% with a cut-off set at > 70.50 ng/ml plasma. Furthermore, a positive correlation between plasma concentrations of cfDNA and cf-miRNA suggests a potential relationship between these two biomarkers. These findings indicated the diagnostic potential of cfDNA and cf-miRNA in distinguishing cholangiocarcinoma, emphasizing their role as promising biomarkers for further investigation and clinical applications. CONCLUSION: Elevated plasma concentrations of cfDNA and cf-miRNA could serve as potential diagnostic tools for distinguishing cholangiocarcinoma from other conditions. cf-miRNA was superior to cfDNA in terms of sensitivity.

Update on the risk factors for opisthorchiasis and cholangiocarcinoma in Thailand.

This study aimed to identify the recent risk factors for Opisthorchis viverrini infection and cholangiocarcinoma (CCA) to improve disease prevention. The participants were divided into the following 3 groups based on their health status: healthy control (nonOV and nonCCA), those with O. viverrini infection (OV), and those with CCA. A questionnaire was used to explore their lifestyle and behaviors. Multivariate logistic regression and backward elimination were used to identify the significant risk factors. The results showed that the significant risk factors for both O. viverrini infection and CCA were age>50 years (odd ratio (OR)=8.44, P<0.001, 95% confidence intervals (CI) 2.98-23.90 and OR=43.47, P=0.001, 95% CI 14.71-128.45, respectively) and raw fish consumption (OR=8.48, P< 0.001, 95% CI 3.18-22.63 and OR=3.15, P=0.048, 95% CI 1.01-9.86, respectively). A history of O. viverrini infection was identified as an additional risk factor for CCA (OR=20.93, P=0.011, 95% CI 2.04-215.10). This study provided an update on the risk factors for O. viverrini infection and CCA. Asymptomatic patients with O. viverrini infection, particularly those>50 years old, should be carefully monitored to prevent CCA.

Susceptibility patterns of Bithynia siamensis siamensis and Bithynia funiculata to Opisthorchis viverrini infection: an indication of the risk of opisthorchiasis transmission in non-endemic areas.

Among the snail species acting as hosts for medically significant trematodes, only three taxa of Bithynia are responsible for transmitting the carcinogenic liver fluke Opisthorchis viverrini to humans in different geographical areas. Although B. siamensis goniomphalos is the primary species responsible for O. viverrini transmission in endemic areas, B. siamensis siamensis and B. funiculata remain potential hosts for transmission. This study objects to determine the susceptibility of B. siamensis siamensis and B. funiculata to O. viverrini to assess the risk of O. viverrini transmission in non-endemic areas. The snails of both species were first introduced to O. viverrini eggs, after which O. viverrini infection was investigated using specific PCR primers after a period of 1, 7, 14, 28, and 56 days post-infection (dpi). Opisthorchis viverrini infection in both B. siamensis siamensis and B. funiculata was high in the early period (1 and 7 dpi) while decreasing over time. It was also shown that the odds of susceptibility to O. viverrini infection in B. siamensis siamensis were 64.5% higher relative to the odds of susceptibility in B. funiculata (P < 0.05). Results of this study provide an early insight into the Bithynia-Opisthorchis relationship and thus have great potential to assess risk and raise awareness of opisthorchiasis in non-endemic regions, especially in regions endemic for B. siamensis siamensis.