Epidemiology of Strongyloides stercoralis and Opisthorchis viverrini infections in northern and northeastern Thailand: Insights from urine-ELISA surveys.

Strongyloides stercoralis and Opisthorchis viverrini are helminth parasites responsible for significantly neglected tropical diseases. This study aimed to evaluate the prevalence of these parasites and the risk factors for S. stercoralis and O.

Diagnostic value of urinary and serum IgG antibodies in evaluating drug treatment response in strongyloidiasis assessed by fecal examination and digital droplet PCR.

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.

Relationship Between Pesticide Exposure Factors and Health Symptoms Among Chili Farmers in Northeast Thailand.

Objectives: The unsafe use of pesticides in agriculture represents a major hazard to human health. This study was conducted to investigate the association between pesticide exposure and health symptoms among chili farmers in northeast Thailand.

Methods: This cross-sectional analytic study included 141 chili farmers in Sakon Nakhon Province, in northeast Thailand.

Examination of Diagnostic Performance of New IgG4 Rapid Test Compared with IgG- and IgG4-ELISAs to Investigate Epidemiology of Strongyloidiasis in Northeast Thailand.

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.

Accuracy of a new rapid diagnostic test for urinary antigen detection and assessment of drug treatment in opisthorchiasis.

Background: Screening for opisthorchiasis, a parasitic worm infection affecting many millions of people in Southeast Asia, has traditionally relied on faecal egg examination such as the formalin-ethyl acetate concentration technique (FECT) and Kato-Katz method. Although the urinary enzyme-linked immunosorbent assay (ELISA) has been used more recently, we developed a urinary antigen-based rapid diagnostic test (RDT) to simplify diagnosis and as a point-of-care testing (POCT) and field applications for surveillance and control of opisthorchiasis.

Methods: A urinary Opisthorchis viverrini (OV)-RDT was developed using immunochromatographic methodology with a specific monoclonal antibody against OV.

Diagnostic performance of Strongyloides-specific IgG4 detection in urine for diagnosis of human strongyloidiasis.

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.

Comparison of a Urine Antigen Assay and Multiple Examinations with the Formalin-Ethyl Acetate Concentration Technique for Diagnosis of Opisthorchiasis.

Detection of worm antigen in urine is a sensitive diagnostic method for opisthorchiasis, particularly for light-intensity infections; however, the presence of eggs in feces is essential for validating results from the antigen assay. To address the issue of low sensitivity of fecal examination, we modified the protocol for the formalin-ethyl acetate concentration technique (FECT) and compared it against urine antigen measurements for detection of the parasite Opisthorchis viverrini. First, we optimized the FECT protocol by increasing the number of drops for examinations from the standard two drops to a maximum of eight.

Long-term Persistence of Opisthorchis viverrini Antigen in Urine: A Prospective Study in Northeast Thailand.

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.

Effects of day-to-day variation of Opisthorchis viverrini antigen in urine on the accuracy of diagnosing opisthorchiasis in Northeast Thailand.

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.

Performance of Mini Parasep SF stool concentrator kit, Kato-Katz, and formalin-ethyl acetate concentration methods for diagnosis of opisthorchiasis in Northeast Thailand.

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.

Concentration of Urine Samples Improves Sensitivity in Detection of -Specific IgG Antibody in Urine for Diagnosis of Strongyloidiasis.

Detection of IgG in urine is an efficient method comparable to that in serum for diagnosis of strongyloidiasis, but the effects of daily variation in urine dilution on diagnostic accuracy are not clearly known. This study evaluated the effects of urine concentration on the detection of parasite-specific IgG by urine enzyme-linked immunosorbent assay (ELISA), particularly in individuals with borderline results or false-negative diagnosis. Optimal concentration conditions were established by comparing -specific IgG antibody levels between unconcentrated and concentrated urine in participants with different infection intensities, namely, healthy control (HC), low-negative (LN), high-negative (HN), and low-positive (LP) groups.

Development and Efficacy of Droplet Digital PCR for Detection of Strongyloides stercoralis in Stool.

Human strongyloidiasis is one of the neglected tropical diseases caused by infection with soil-transmitted helminth Strongyloides stercoralis. Conventional stool examination, a method commonly used for diagnosis of S. stercoralis, has low sensitivity, especially in the case of light infections.

Genetic diversity and population structure of Haemonchus contortus in goats from Thailand.

Haemonchus contortus is one of the most economically important parasitic nematodes affecting small ruminant livestock worldwide. This study was conducted to elucidate the genetic diversity and population structure of this nematode in Thailand based on mitochondrial DNA markers, the nicotinamide dehydrogenase subunit 4 (nad4) and the cytochrome c oxidase subunit 1 (cox1) genes. One hundred and thirty-six adult worms were obtained from 86 abomasa of slaughtered goats from 13 different localities in 5 regions of Thailand.

Evaluation of a Rapid IgG4 Lateral Flow Dipstick Test to Detect Strongyloides stercoralis Infection in Northeast Thailand.

Strongyloides stercoralis affects more than half a billion people worldwide, and hyperinfection in immunocompromised patients can be fatal. Elimination of this neglected tropical disease requires field-applicable diagnostic tools. We conducted a laboratory evaluation of a lateral flow rapid dipstick test (SsRapid™) using sera samples from a Strongyloides-endemic area in northeast Thailand.

Analysis of Daily Variation for 3 and for 30 Days of Parasite-Specific IgG in Urine for Diagnosis of Strongyloidiasis by Enzyme-Linked Immunosorbent Assay.

Recent work has found urine analysis to be as sensitive as serology for diagnosis of strongyloidiasis. Here, we examined the daily variation of Strongyloides-specific IgG in urine by qualitative and quantitative ELISA and its effects on diagnostic accuracy and reliability. In the first part of the study, matched urine and fecal samples were collected from project participants in northeast Thailand for three consecutive days.

Impact of geography and time on genetic clusters of Opisthorchis viverrini identified by microsatellite and mitochondrial DNA analysis.

Infection by the small liver fluke, Opisthorchis viverrini, causes serious public health problems, including cholangiocarcinoma, in Thailand and southeastern Asian countries. Previous studies have reported that O. viverrini represents a species complex with varying levels of genetic differentiation in Thailand and Lao PDR.

Influence of Water Irrigation Schemes and Seasonality on Transmission Dynamics of in the Snail Intermediate Host, in Rice Paddy Fields in Northeast Thailand.

is a fish-borne zoonotic trematode that causes significant public health problems in Southeast Asia. Its life cycle requires snails as the first intermediate hosts, fish, and human and/or carnivore hosts. This study assessed impacts of land use practice for rice cultivation and seasonality on the transmission dynamics of in in rice paddy field habitats.

Comparing the performance of urine and copro-antigen detection in evaluating Opisthorchis viverrini infection in communities with different transmission levels in Northeast Thailand.

To combat and eventually eliminate the transmission of the liver fluke Opisthorchis viverrini, an accurate and practical diagnostic test is required. A recently established urine antigen detection test using monoclonal antibody-based enzyme-linked-immunosorbent assay (mAb-ELISA) has shown promise due to its high diagnostic accuracy and the use of urine in place of fecal samples. To further test the utility of this urine assay, we performed a cross sectional study of 1,043 people in 3 opisthorchiasis endemic communities in northeast Thailand by applying urine antigen detection together with copro-antigen detection methods.

EVALUATION OF A COMMERCIAL STOOL CONCENTRATOR KIT COMPARED TO DIRECT SMEAR AND FORMALIN-ETHYL ACETATE CONCENTRATION METHODS FOR DIAGNOSIS OF PARASITIC INFECTION WITH SPECIAL REFERENCE TO OPISTHORCHIS VIVERRINI SENSU LATO IN THAILAND.

Opisthorchiasis and cholangiocarcinoma (CCA) are major public health problems in Thailand and countries in the lower Mekong Subregion. Elimination of opisthorchiasis will be an important step toward the prevention, control and reduction of CCA. In order to achieve this goal, a sensitive and robust diagnostic method is required to identify people with current Opisthorchis viverrini sensu lato infection as the parasite is a group 1 carcinogen believed to be an etiology of CCA.

Cercarial emergence patterns for Opisthorchis viverrini sensu lato infecting Bithynia siamensis goniomphalos from Sakon Nakhon Province, Thailand.

Unlabelled: Opisthorchis viverrini sensu lato is a food-borne trematode which is classified as a class 1 carcinogen, with infection potentially leading to cholangiocarcinoma. Snails of the genus Bithynia act as the first intermediate hosts and an amplifying point in the parasite life cycle. In order to investigate seasonal effect on transmission dynamics of O.

Comparison of infectivity, metacercarial burden and host mortality induced by Opisthorchis viverrini sensu lato cercariae from Lao PDR compared with Thailand in cyprinid fish, Barbonymus gonionotus.

Background: Previous studies indicate that Opisthorchis viverrini sensu lato (s.l.) is a species complex with strong associations to geographical regions, i.