Opisthorchis viverrini infection remains an important public health problem in Southeast Asia, particularly among rural populations in Northeast Thailand. Despite control efforts, transmission remains uninterrupted due to persistent behavioral and environmental factors. To better understand the longitudinal patterns of opisthorchiasis after selective praziquantel treatment, this study aimed to determine the incidence and reinfection rates in the study population and identify risk factors associated with O. viverrini infection. Based on a prospective study, the status of opisthorchiasis was monitored in a cohort of participants (n = 612) in Northeast Thailand using the formalin-ethyl acetate concentration technique (FECT) and O. viverrini antigen detection in urine by Enzyme-linked immunosorbent assay (ELISA). The baseline prevalence of O. viverrini infection was 41.0% by urine antigen assay, compared to 8.1% by FECT. Over the 24-week study period, the calculated incidence of infection was 64.6/100 person-years, and the reinfection rate after PZQ treatment, as measured by urine ELISA, was 63.7/100 person-years. Based on FECT, a tenfold lower incidence (7.5/100 person-years) and reinfection rate (5.9/100 person-years) were observed. Risk factor analysis identified raw fish consumption in the previous 6 months (aRR = 7.52; p < 0.001), frequent raw fish consumption (>10 times per month) (aRR = 3.60; p < 0.001), and previous praziquantel treatment aRR = 1.49; p = 0.032) as significant risk factors for infection. The results demonstrated that the persistence of opisthorchiasis prevalence is driven mainly by the incidence of infection and reinfection after chemotherapy, as assessed by urine antigen assay and FECT. Behavioral risk factors, particularly the consumption of raw fish, remain the primary risk of parasite transmission. Therefore, comprehensive intervention measures consisting of sensitive diagnostics, drug treatment, and culturally appropriate interventions are required.

Background Human opisthorchiasis caused by Opisthorchis viverrini infection is a well‑established risk factor for cholangiocarcinoma (CCA) in Southeast Asia, particularly in Northeast Thailand. Targeted screening and treatment of populations at high risk of O. viverrini infection are central to CCA prevention strategies. Recent studies have demonstrated that urine antigen detection exhibits superior diagnostic accuracy, compared to conventional fecal examination. Moreover, a rapid diagnostic test for O. viverrini (OV‑RDT), has recently been developed and reported to be promising for point‑of‑care use. The present study aimed to evaluate the diagnostic accuracy of the OV‑RDT under field conditions in Northeast Thailand, in comparison to urine antigen detection, coproantigen‑antigen detection, and conventional fecal examination methods for the diagnosis of opisthorchiasis. Methods The prevalence of opisthorchiasis and the diagnostic accuracy of OV-RDT, urine antigen ELISA, coproantigen ELISA, and quantitative fecal examination using the formalin–ethyl acetate concentration technique (FECT) were comparatively assessed for sensitivity, specificity and accuracy in a sample population ( n =1,355) from communities in Northeast Thailand. Results The prevalence of O.viverrini infection varied substantially depending on the diagnostic method used: 6.2% by FECT, 62.2% by OV-RDT, 62.8% by urine antigen ELISA, and 64.4% by coproantigen ELISA. The diagnostic sensitivity of OV-RDT ranged from 84.5% to 94.5% when compared with either the primary reference or composite reference standards, demonstrating moderate to high diagnostic accuracy (AUC: 0.59–0.94). Antigen detection assays, including urine antigen ELISA, coproantigen ELISA, and OV-RDT, showed strong agreement between methods, with kappa values ranging from 0.71 to 0.86. Furthermore, OV-RDT positivity was significantly associated with antigen levels in both urine and fecal samples, as well as fecal egg counts ( P < 0.05). Conclusion Field application of the OV‑RDT demonstrated superior diagnostic accuracy compared to conventional fecal examination in the current low‑endemicity setting of opisthorchiasis. The OV‑RDT showed high qualitative and quantitative concordance with urine antigen ELISA and strong agreement with coproantigen‑antigen ELISA for screening O. viverrini infection. These findings support the potential of OV‑RDT as a point‑of‑care test (POCT) to facilitate rapid, non‑invasive large‑scale screening, avoiding labor‑intensive stool microscopy in opisthorchiasis control programs.

INTRODUCTION:Infection with the carcinogenic fish-borne trematode Opisthorchis viverrini, known as opisthorchiasis, is a major cause of biliary cancer (cholangiocarcinoma). Despite decades of disease prevention and control in Thailand, the parasite remains endemic. Here we apply a novel antigen assay for mass screening of opisthorchiasis and compare the prevalence against the conventional examination and analyze risk factors associated with current O. viverrini infection. MATERIALS AND METHODS:We conducted a large-scale cross-sectional survey to assess transmission of O. viverrini in the North, Northeast, and Eastern regions of Thailand. We screened randomly selected people (age 15 years and over) in 23 sub-districts, within 21 provinces, with a target sample size of 1,000 per sub-district. Each participant was screened for multiple helminth infection by fecal examination (quantitative formalin-ethyl acetate concentration technique; FECT), and the antigen assay by monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) was applied to urine samples to detect O. viverrini. We collected risk factors for O. viverrini infection using standardized questionnaire surveys. The data were analyzed with regression models which correlated individual-level explanatory variables against i) infection status with O. viverrini and ii) the intensity of infection, as measured by the antigen assay or FECT. FINDINGS:Of the 20,322 individuals enrolled, 19,465 provided urine samples for antigen detection by ELISA and 18,929 provided fecal samples for examination by FECT. The urine antigen assay revealed an overall opisthorchiasis prevalence of 50.3%, a fourfold increase over the 12.2% prevalence detected by FECT. Marked spatial heterogeneity was observed, with antigen-based prevalence estimates ranging from 22.2% to 71.4% and several localities exceeding 60%. When assessed against a composite reference standard (combined ELISA and FECT), the urine ELISA yielded a diagnostic sensitivity of 91.6%, compared with 21.9% for FECT. We found a positive correlation between fecal egg counts and the concentration of worm antigen in urine across study sites. The ratio between the prevalence of O. viverrini observed by the antigen assay and FECT was high in provinces with a low mean number of O. viverrini eggs, and the ratio approached unity as the mean eggs per gram of stool (EPG) increased. Similar aggregate distribution patterns of fecal egg counts (EPG) and urine antigen concentrations suggest that the urine assay has potential for quantitative diagnostic evaluations. When analyzing individual-level risk factors, we further identified age, sex, occupation, a history of prior treatment with praziquantel, history of O. viverrini examination, and raw fish consumption as predictive of infection with O. viverrini, while a higher education level and certain occupations emerged as protective factors. CONCLUSIONS AND RECOMMENDATIONS:Application of the antigen assay to diagnose O. viverrini infection yielded a four-fold higher prevalence than the fecal egg examination, with the highest difference in low endemicity regions, which suggests that previous surveys may have underestimated the extent of opisthorchiasis in Thailand. Given the ease of urine sample collection, our study highlights the potential for application of the antigen assay as a new tool in the control of opisthorchiasis.

Strongyloides stercoralis infection is a neglected tropical disease with a global distribution. Serodiagnosis is a sensitive method, but improving its performance and simplifying into a point-of-care test (POCT) are needed. This study aimed to improve the diagnostic performance of serological tests using partially purified Strongyloides ratti antigen in an enzyme-linked immunosorbent assay (ELISA) and an immunochromatographic test (ICT). Crude S. ratti antigen was purified by an IgG affinity column to partition the antigen into flow-through, washing fraction (WF), and elution fractions. Optimized ELISA and ICT using crude and antigen fractions were used to analyze sera from three groups of subjects. Group 1 comprised subjects with proven strongyloidiasis, Group 2 were subjects with other parasitic infections, and Group 3 were negative parasitic infections. The diagnostic performance and Kappa agreement of the serological tests were analyzed and compared, using larvae detection as the reference test (fecal examination). The results showed that the WF was the most efficient antigen in terms of sensitivity and specificity, as determined by the ELISA and ICT. Kappa’s agreement between fecal examination and WF-ELISA was moderate (Kappa = 0.52), and WF-ICT was almost perfect (Kappa = 0.94). The WF antigen reduced cross-reactivity to other parasitic infections, that is, Opisthorchis viverrini, Taenia spp., and hookworms, compared to crude S. ratti antigen when assessed by ELISA and ICT. We concluded that the WF of purified S. ratti improved the ELISA and ICT diagnostic performance, and the latter assay format could be used as a POCT for screening and controlling strongyloidiasis.IMPORTANCEThis study aimed to improve the serological diagnosis of strongyloidiasis, a disease caused by infection with the intestinal nematode Strongyloides stercoralis, by evaluating the impact of Strongyloides ratti antigen purification using an IgG affinity column for detecting parasite-specific IgG in serum via enzyme-linked immunosorbent assay (ELISA) and immunochromatographic test (ICT) formats. Compared to crude S. ratti antigen, the washing fraction (WF) of the purified antigen demonstrated significantly improved sensitivity and specificity in both ELISA and ICT, achieving strong diagnostic concordance with the gold-standard fecal examination. Furthermore, the WF antigen fraction exhibited reduced cross-reactivity with coinfections caused by the liver fluke (Opisthorchis viverrini), tapeworms (Taenia spp.), and hookworms. These findings underscore antigen purification as a promising strategy to enhance the accuracy of strongyloidiasis serodiagnosis.

Background: Wild felids have been in decline, which has been linked to health issues. Parasitic infections, including zoonotic ones, can contribute to the challenges faced regarding wildlife conservation efforts and may pose a risk to human health, particularly for people working at or visiting zoological parks. This study investigated the occurrence of parasitic infections in the Felidae within Thai zoo parks. Methods: The fecal samples were collected from 93 Felidae individuals residing in four zoo parks. The parasitological technique involved sugar floatation, and a formalin-ethyl acetate concentration technique (FECT) was also employed. Additionally, a molecular technique was used to detect Toxoplasma gondii DNA in feces. For blood samples, 22 were tested for T. gondii DNA using the PCR technique. To detect T. gondii antibodies in serum, an indirect fluorescent antibody test (IFAT) was performed, and the result was confirmed using an enzyme-linked immunosorbent assay (ELISA). Results: The prevalence of intestinal parasites in captive felids was 23.7%, with the highest rates observed for hookworms (8.6%), Toxascaris leonina (7.5%), coccidia (4.3%), Strongyloides spp. (2.1%), and Opisthorchis-like egg (1.1%). Among the Felidae, lions and white lions (Panthera leo) exhibited the highest prevalence of parasitic infection, particularly T. leonina. Furthermore, a substantial percentage (63.6%) of the animals tested positive for T. gondii antibodies using both IFAT and ELISA. Conclusion: These findings highlight the importance of addressing the circulation of parasites, such as T. gondii, hookworm, T. leonina, and coccidia in environments where animals and humans closely interact, such as wildlife zoos. Implementing preventative measures and adopting a one-health approach are strongly encouraged to control parasites and reduce the risk of infection for animals and humans.

Cryptosporidium spp. is the most frequent agent in Algeria that causes neonatal diarrhea in calves, with high symptomatic diarrhea in pre-weaned dairy calves. The study aims to measure the prevalence, distribution, and genotype of Cryptosporidium-infected calves in one of Algeria's high milk production areas (North Central and Northeast). From 35 dairy cattle farms were selected 172 (77 with diarrheic and 95 without diarrheic symptoms) calves aged less than 60 days. Twenty-three farms (65.71%) were detected with cryptosporidiosis using a modified Ziehl-Neelsen stain, whereby 68 calves (39.53%) were obtained positive. The Copro-ELISA test gave an individual prevalence of (37.66%, 22.11%) in calves with diarrhea and asymptomatic calves, respectively. Fifty positive cases confirmed with the previous tests reconfirmed by the target of S18 gene (SSUrRNA), in addition to the sequencing, were obtained from species C. parvum in all the analyzed samples. The subgenotype of C. parvum was obtained by amplifying the target gene of gp60, successfully confirmed by C. parvum type II (IIaA15G2R, IIaA16G2R1, and IIaA17G2R1). Our results confirmed the frequency of cryptosporidiosis in dairy calves from farms in Northern Algeria, with a pathogenic role in the calves, with potential zoonotic risk from food contamination.

The viability and host-seeking behavior of Strongyloides larvae are significantly influenced by soil conditions, emphasizing the critical role of environmental control in disease management. This is particularly relevant given the growing concerns about drug resistance resulting from mass chemotherapy or the use of chemical nematicides. Strongyloides stercoralis was effectively inactivated by exposure to 50 °C for both 12 and 24 h (long-term exposure). Strongyloides ratti was inactivated by 50 °C for 20 min (short-term exposure), 9% saline for 50 min, and a combination of 4% saline and 40 °C for 50 min. The combined treatment successfully inactivated S. ratti in four soil mediums using 5% saline at a central temperature of 40 °C. Thermotaxis responses to noxious heat revealed attraction at 40 °C, increased localized searching at 45 °C, and complete inactivation at 50 °C. Larvae migrating within agar at 45 °C were more readily inactivated. Long-range heat attraction at 5 cm resulted in the inactivation of up to 50% of incoming larvae; however, heat-high concentration saline traps at 3 cm distance proved ineffective. Thermal–saline agar trapping demonstrated promise for larval removal in sand, loam, and laterite soils. This method offers a promising approach to larval removal while minimizing hazards to non-target organisms.

Deer louse flies (Lipoptena spp.) are hematophagous ectoparasites of cervids. The genus Lipoptena comprises 32 species, some of which are of veterinary importance as vectors of various pathogens, and are also known to attack human hosts. Recently, deer louse flies have been observed during annual checkups of captive cervids at Khon Kaen Zoo in Khon Kaen, Thailand. However, data on their specific identity and prevalence remain limited. This study aims to identify louse fly samples from captive cervids at Khon Kaen Zoo using morphological and molecular analyses. A total of 60 louse flies were collected from 17 captive cervids and identified based on their morphology. Major morphological characteristics, including mesothoracic bristle patterns, abdominal tergal plate bristles, and terminalia structure indicated that the Khon Kaen louse fly is Lipoptena axis Maa, 1965. Phylogenetic analysis of sequences from a portion of the mitochondrial cytochrome c oxidase subunit I (COI) gene was performed, which confirmed that L. axis of this study belongs to the cervi group, which is distinct from other groups of Lipoptena species. This study represents the first report of L. axis in Thailand. We provide an updated taxonomic key for the identification of Lipoptena species in the cervi group.

Strongyloidiasis, caused by Strongyloides stercoralis, is a neglected tropical disease with a global distribution. The infection can be fatal in immunocompromised individuals, and accurate diagnosis leading to timely treatment can save lives. Serodiagnosis is a sensitive method for diagnosis and is recommended for screening high-risk individuals. A point-of-care rapid test will facilitate the screening activities, especially in low-resource settings. This study aims to apply a new IgG4 immunochromatographic test using S. stercoralis recombinant antigen (SsRapid® cassette test) and to compare it with in-house IgG and IgG4 enzyme-linked immunosorbent assays (IgG- and IgG4-ELISAs) using native Strongyloides ratti antigen to investigate the epidemiology of strongyloidiasis in northeast Thailand. A total of 300 people participated, with 136 males and 164 females of a similar mean age. The reference tests were fecal examinations using the formalin-ethyl acetate concentration technique and an agar plate culture technique. The prevalence of S. stercoralis determined by SsRapid (81.7%) was significantly higher than that by fecal examinations (43.3%) or by antibody detection by IgG-ELISA (53.0%) or IgG4-ELISA (44.0%). The diagnostic sensitivities of SsRapid, IgG-ELISA, and IgG4-ELISA were found to be 93.9%, 77.7%, and 63.1%, respectively. The rate of positive tests by the SsRapid was significantly correlated to the levels of Strongyloides-specific IgG4 and IgG antibodies. By all diagnostic methods, male participants had a significantly higher prevalence of strongyloidiasis than females. Age was significantly associated with the concentration of specific serum IgG but not with the SsRapid grading score. In conclusion, SsRapid was shown to be a sensitive and valuable diagnostic test for the epidemiology study of strongyloidiasis.

Detection of Strogyloides-specific IgG antibodies in urine and serum has been used in diagnostic and epidemiological studies on strongyloidiasis. However, the usefulness of these assays in assessing responses to anthelmintic treatment is unclear. Thus, we evaluated the diagnostic performance and temporal profiles of Strongyloides-specific IgG antibodies in a cohort of participants at baseline and post-treatment. The participants were prospectively screened for baseline parasitic infections by fecal examination [agar plate culture technique (APCT) and formalin-ethyl acetate concentration technique (FECT)] and digital droplet polymerase reaction (ddPCR) for Strongyloides stercoralis. At each sampling point, Strongyloides-specific IgG in urine and serum were measured by an in-house S. ratti-based enzyme-linked immunosorbent assay (ELISA). At baseline, 169 of 351 participants (48.1%) had S. stercoralis infection by the combined fecal examination and ddPCR. The diagnostic sensitivities of IgG in urine and serum were 91.1% and 88.2%, respectively. The participants were given treatment with a single oral dose of ivermectin (IVM, 200 μg/kg) and were followed up by fecal and immunological diagnosis at 3 to 18 months post-treatment. The cure rate of IVM treatment evaluated by APCT and ddPCR was 88.3% at three months post-treatment. The profiles of IgG in urine in the curative treatment group showed a significant trend of decline with time post-treatment (Kruskal-Wallis test = 113.4-212.6, p value < 0.0001) and the lowest levels were seen 12 months post-treatment. The treatment response (> 50% reduction in urinary IgG antibody units) was 100%, and conversion from positive to negative results was 65.4%. The treatment response and conversion to negative assessed by serum IgG-ELISA were similar to those by urine IgG-ELISA. The results from this long-term diagnostic study highlight the utility of urinary IgG and serum IgG for screening and monitoring treatment outcomes in strongyloidiasis.

Detection of anti-Strongyloides IgG in urine by enzyme-linked immunosorbent assay (ELISA) for diagnosis of strongyloidiasis reportedly has comparable performance to conventional serum assays. Initial comparisons of urine assays using commercial ELISA kits designated for serology have shown its diagnostic potential but sub-optimal accuracy. In the present study, we optimized urine ELISA protocols based on different antigen types and evaluated their accuracies in determining the epidemiology of strongyloidiasis in Northeast Thailand. Paired urine and fecal samples of 966 individuals from the study community were collected for three consecutive days and tested for strongyloidiasis. We compared three ELISA protocols using different antigens including crude S. stercoralis antigen (Ss-ELISA), crude S. ratti antigen (Sr-ELISA) and recombinant NIE antigen (NIE-ELISA) and fecal examination by agar plate-culture (APCT) technique and formalin-ethyl acetate concentration technique (FECT). The optimized ELISA protocols using three different antigen sources yielded significantly higher prevalence rates of strongyloidiasis (58.9–65.1%) than those by fecal examination methods (19.7%). The prevalence of strongyloidiasis determined by ELISA protocols significantly increased with age (p value < 0.0001) and males had higher prevalence than females (p value < 0.0001). Diagnostic agreements between ELISA protocols were moderate (κ = 0.461–0.586) and the agreement between each ELISA protocol and fecal examinations were slight (κ = 0.139–0.210). The results obtained by urine ELISA protocols using three different antigens showed comparable diagnostic performances, provided further supports for the utility of urine as an alternative clinical specimen for diagnosis of strongyloidiasis.

Antigen detected in urine for the diagnosis of opisthorchiasis has a low daily variation; however, the longer term variability in antigen concentrations is unknown. In this study, we prospectively monitored Opisthorchis viverrini antigen concentrations for 30 consecutive days and at subsequent monthly intervals in a cohort of opisthorchiasis-positive individuals. On the basis of the monoclonal antibody-based ELISA, the profiles of antigen-positive rate and antigen concentration exhibited no significant change over 30 days with a mean proportion positive of 87.1% (range 73.7%-100%), and the average antigen concentration was 29.7 ± 2.2 ng/mL (mean ± SE). The urine antigen concentration at baseline was similar to the subsequent measurements at 2, 4, 6, and 10 months in the follow-up study (P > 0.05). The consistency and low daily and long-term fluctuation of O. viverrini antigen in urine demonstrates the reliability of urine assay for diagnosis of opisthorchiasis.

It is known that Opisthorchis viverrini (OV) is the most significant risk factor for the development of cholangiocarcinoma (CCA); hence, it is also known as carcinogenic parasite. Effective control and elimination of OV infection should significantly reduce O. viverrini-related CCA. This chapter includes details of the three recently developed innovative tools, namely the Isan cohort database software, an OV-RDT for screening of O. viverrini, and an ultrasound telecommunication system. Past and current control programs, i.e., education, medication, and sanitation were discussed and stressed the need for a comprehensive control program which encompasses primary, secondary, and tertiary patient care programs for confirmation and management of suspected CCA cases. The approach of mathematical modeling for control of OV and CCA was also briefly described. Additionally, we highlighted the current progress toward control of OV and CCA in Thailand and potential for expansion into nearby countries in Southeast Asia.

Background and Aim: Captive animals are susceptible to parasitic diseases due to the stress and confinement they experience. In addition, they can serve as reservoirs of zoonotic parasites that have the potential to infect humans. To investigate this possibility, we estimated the prevalence of gastrointestinal (GI) parasites in captive mammals at Khon Kaen Zoo, Thailand. Materials and Methods: One hundred and forty-seven individual mammals (37 primates, 43 carnivores, 62 herbivores, and 5 rodents) were examined for parasitic infections by fecal examination daily for 3 consecutive days using the formalin-ethyl acetate concentration technique (FECT) and the agar plate culture method. Results: According to FECT, the overall prevalence of GI parasites was 62.6% (92/147). Within animal groups, the numbers were as follows: 67.6% (25/37) in primates, 23.3% (10/43) in carnivores, 85.5% (53/62) in herbivores, and 80.0% (4/5) in rodents. Using the agar plate culture method, 21.43% (27/126) were positive for Strongyloides spp. and hookworm infections. The GI parasites identified belonged to three categories: protozoa (including Entamoeba histolytica species complex, Entamoeba coli, Giardia spp., coccidia, and ciliated protozoa), trematodes (minute intestinal flukes and rumen flukes), and nematodes (strongyle/hookworm, Strongyloides spp., Ascarididae, and Trichuris spp.). Conclusion: The findings of this study indicate the prevalence of several GI parasites in zoo animals with the potential for transmission to humans, given the animals’ close proximity to both visitors and animal caretakers.

Background Detection of parasite-specific IgG in urine is a sensitive method for diagnosis of strongyloidiasis and gives similar accuracy to serum IgG. However, there are no data concerning detection of IgG subclass in urine. To further explore the utility of diagnosis from urine samples, we evaluated the diagnostic performance of IgG4 in urine compared with parasitological and other immunological methods. Methods The urine and sera included proven strongyloidiasis (group 1, n = 93), other parasitic infections (group 2, n = 40) and parasite negatives (group 3, n = 93). The performance of Strongyloides -specific IgG4 in urine for diagnosis of strongyloidiasis using fecal examinations as the reference standard was assessed. Results With fecal examination as a gold standard, Strongyloides -specific IgG4 in urine had 91.4% sensitivity and 93.2% specificity while serum IgG4 had 93.6% sensitivity and 91.0% specificity. IgG4 in both urine and serum had almost perfect diagnostic agreements with fecal examination (Cohen's kappa coefficient was > 0.8). Cross-reactivity to Opisthorchis viverrini and Taenia spp. of IgG4 in urine were 7.5% and 12.5% in serum. Concurrent analyses of total IgG in urine and serum showed that the sensitivities (97.9–100%) and specificities (88.7–91.0%) were similar ( P > 0.05). The sensitivity for parasitological examination by the formalin-ethyl acetate concentration technique (FECT) was 49.5% and that for agar plate culture technique (APC) it was 92.6%. Conclusion Our findings showed that specific IgG4 detection in urine yielded similar diagnostic performance to the same biomarkers in serum. This suggests that accurate diagnosis of strongyloidiasis can be performed using urine samples and IgG4 is a valid choice of diagnostic marker. Further assessment is required to assess the utility of urine IgG4 for measuring the response treatment in strongyloidiasis. Graphical Abstract

Antigen detection in urine using an enzyme-linked immunosorbent assay (ELISA) is more sensitive than fecal examination for diagnosis of opisthorchiasis and for assessment of the effects of drug treatment. It is not known whether day-to-day variation of urine composition, including levels of Opisthorchis viverrini antigen, influences the urine assay. We investigated this topic with the cooperation of participants from two localities in Northeast Thailand. Project participants were screened for parasite infections for three consecutive days using the quantitative formalin-ethyl acetate concentration technique (FECT) to detect O. viverrini eggs and the urine ELISA for detection of O. viverrini antigen. A subset of participants (n = 801) with matched fecal and urine samples were analyzed for comparison of inter-day prevalence estimates and the performance of the urine assay compared against FECT for diagnosis of opisthorchiasis. The daily prevalence measured by the urine assay ranged between 29.0%-30.2% while those by FECT ranged between 11.9%-20.2%. The cumulative three-day prevalence estimate determined by the urine antigen assay was 30.3%, which was significantly higher than that by FECT (20.2%, p < 0.05). A significant positive correlation was found between the concentration of antigen in urine and fecal egg counts (p < 0.001). Overall, the urine assay had better diagnostic performance for opisthorchiasis than fecal examination by FECT. The high sensitivity plus negligible daily variation of O. viverrini antigen in urine indicates the utility of the urine assay for diagnosis, as well as population screening, of opisthorchiasis.

Background Control and elimination of the liver fluke ( Opisthorchis viverrini ) is a primary preventive strategy against cholangiocarcinoma in Southeast Asia. A sensitive parasitological diagnostic method is required to facilitate a surveillance and control program. In this study, we evaluated the performance of Mini Parasep ® SF stool concentrator kit (stool kit) compared with Kato-Katz (KK) and the quantitative formalin-ethyl acetate concentration technique (FECT) for detection of O. viverrini and co-endemic parasitic infections. Methods A cross-sectional survey for parasitic infection in residents aged > 15 years in a community in Kalasin province, Northeast Thailand, was conducted in 2018. Fecal samples were collected and screened by KK method, and a subset of samples was further examined by the stool kit and FECT methods. The results were analyzed for prevalence of parasitic infections in addition to the diagnostic performance of the methods for qualitative and quantitative detection of helminthiases. Results The initial survey of parasitic infection determined by the KK method ( n = 567) showed the prevalence of O. viverrini was 32.63%, followed by Taenia 2.65%, echinostomes 1.76%, hookworms 1.41%, Trichuris trichiura 0.53% and Strongyloides stercoralis 0.53%. Within a subset of samples tested with multiple diagnostics ( n = 150), the detection rates of O. viverrini by the stool kit, FECT and KK methods were 27.3%, 30.7% and 28.7%, respectively. The diagnostic sensitivity for opisthorchiasis was similar for FECT (75.5%), KK(66.0%) and the stool kit (67.3%). For other parasitic infections, FECT and stool kit methods performed better than KK, particularly in detecting minute intestinal flukes (MIF), S. stercoralis and coinfections. When measuring the intensity of O. viverrini infection (fecal egg counts), the stool kit results showed a significant positive correlation with KK and FECT ( P < 0.05). Conclusions As the stool kit is simple to use and shows a comparable performance to FECT, it may serve as an alternative method of fecal examination for screening of helminthiasis including opisthorchiasis. Graphical abstract

Background and Aim:The brown dog tick, Rhipicephalus sanguineus sensu lato, is the most common tick found on domestic dogs in Southeast Asia, including Thailand. Canine tick-borne pathogens are a public health concern worldwide. Tick-borne diseases are diagnosed by identifying pathogens based on the morphological or molecular analyses of dog blood samples. However, the collection of ticks, a non-invasive procedure, is easier than drawing blood. This study aimed to demonstrate the usefulness of collecting brown dog ticks for the diagnosis of tick-borne diseases and for estimating the prevalence of tick-borne pathogens among companion dogs in Khon Kaen, Northeast Thailand.Materials and Methods:Seventy brown dog ticks from 70 companion dogs in Khon Kaen Province, Thailand, were evaluated for molecular evidence of tick-borne pathogens, including Babesia spp., Ehrlichia canis, and Hepatozoon canis. Ticks were collected from dogs at a private animal hospital based on the presence of at least one of the three inclusion criteria: fever, anorexia, or lethargy. Molecular diagnosis was performed using conventional polymerase chain reaction for the detection of pathogens.Results:Of the 70 ticks collected from 70 sick dogs, 55 (78.57%) were positive for tick-borne pathogens. The most common infection was a single infection with H. canis (65.71%) followed by Babesia spp. (31.43%) and E. canis (30.00%). Coinfection was observed in 14 ticks (20.00%), and coinfection with Babesia spp. and E. canis was the most prevalent double infection (n = 6). The prevalence of coinfection was identical for H. canis mixed with Babesia spp. and H. canis mixed with E. canis (n = 4).Conclusion:The present study showed that tick-borne pathogens are highly prevalent among companion dogs in Khon Kaen Province. Therefore, we encourage an increase in tick control or the reduction and prevention of tick-borne diseases in this region. Furthermore, this study revealed that ticks are valuable samples for the molecular detection of tick-borne pathogens.

Cystic echinococcosis is a zoonotic parasitic disease caused by Echinococcus species. Tanzania is one of the endemic countries with cystic echinococcosis. This study focussed on identifying genotypes of Echinococcus spp. in Tanzania. We collected 7 cysts from cattle in Mwanza municipal (n=4) and Loliondo district (n=3). The cysts from Mwanza were all E. ortleppi and fertile. In contrast, the cysts from Loliondo were all E. granulosus sensu stricto and sterile. Two from the 4 cysts were a new haplotype of E. ortleppi (G5). These results can improve the preventive and control programs for humans and livestock in Tanzania. To our knowledge, this study is considered the first to identify the genotype and haplotype of Echinococcus spp. in Tanzania.

The objective of this study was to examine the change in pain and physical function that occurs while waiting for major arthroplasty. Data were collected prospectively from a cohort of 313 patients who were waiting > 1 month for total hip arthroplasty or total knee arthroplasty. The WOMAC and the SF-36 health status instruments were administered at the time the patient was placed on the waiting list and again just before surgery. Minimal amounts of change in pain and physical and psychosocial function occurred for hip and knee arthroplasty patients while they waited. Overall, waiting time did not appear to have a negative impact on the amount of pain and dysfunction experienced.