This review highlights the current status and control of liver fluke infections in the Mekong Basin countries where Opisthorchis and Clonorchis are highly endemic. Updated data on prevalence and distribution have been summarized from presentations in the “96 Years of Opisthorchiasis. International Congress of Liver Flukes”. It is disturbing that despite treatment and control programs have been in place for decades, all countries of the Lower Mekong Basin are still highly endemic with O. viverrini and/or C. sinensis as well as alarmingly high levels of CCA incidence. A common pattern that is emerging in each country is the difference in transmission of O. viverrini between lowlands which have high prevalence versus highlands which have low prevalence. This seems to be associated with wetlands, flooding patterns and human movement and settlement. A more concerted effort from all community, educational, public health and government sectors is necessary to successfully combat this fatal liver disease of the poor.

Background: Helminth infections continue to pose serious health problems in Thailand. The infections of greatest concern are opisthorchiasis and hookworm. Objectives: We evaluated the prevalence of these infections. The Thai Ministry of Health established a national health plan in 1995 to coordinate health plans for the provincial public health sectors. Methods: A national survey based on probability sampling, interviews, and stool examinations was conducted in 2009 to gather prevalence information of the helminth infections. Results: We found an overall prevalence of helminthiasis among 15,555 Thai people of 18.1%. The highest prevalence was found in the northeastern regions of Thailand. By comparison with previous surveys conducted over the past 5 decades, the prevalence rates have decreased. However, pockets of high infection remain, particularly in the north and northeast of Thailand. Conclusions: Targeted intervention by means of educational programs and public health intervention, and continuing surveillance are indicated.

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The quantitative formalin ethyl acetate concentration technique (QFEC) was compared to agar plate culture (APC) for the detection of Strongyloides stercoralis larvae. QFEC could substitute for APC only when the parasite load was higher than 50 larvae per g of stool. This study serves as a good reminder to those conducting stool exams about the sensitivity and specificity limitations of both techniques.Agar plate culture (APC) is a highly effective technique for the coprological diagnosis of human strongyloidiasis (1,(5)(6)(7)(8)10). But despite its high sensitivity, there are several disadvantages to APC. It is expensive, it takes a long time before results can be provided, and there is also a risk of infection for the technicians. The quantitative formalin ethyl acetate concentration technique (QFEC) is another effective and more rapid method to detect and quantify intestinal helminths, e.g., Ascaris lumbricoides (3) and Opisthorchis viverrini (4). In the present study, we compared APC results to the different intensities of Strongyloides stercoralis larvae determined by QFEC.Stool samples (n ϭ 1,233) were collected from populations in northeast Thailand and examined by APC (6) and QFEC (3). For APC, 3-g portions of individual fecal samples were placed in the centers of nutrient agar plates during the field survey. The plates were kept in a box and transported at room temperature (30 to 35°C) to the laboratory, where they were incubated for another 5 days at room temperature. The agar plates were examined under a stereomicroscope for the presence of tracks from moving larvae or free-living adults on the 3rd and 5th days. All microscopically positive dishes were further processed by washing the surface of the agar with a 10% formalin solution to collect worms for species identification. The differentiation of S. stercoralis larvae from hookworm larvae was performed under microscopic magnification of ϫ40. For QFEC, 2 g of individual fecal samples was weighed out and then stirred well in a vial containing a merthiolate-iodineformalin solution (2). The preserved stools were processed by QFEC (3). Briefly, the preserved fecal suspension was filtered through two layers of wet gauze into a centrifuge tube. The volume was adjusted to 10 ml with 10% formalin. Two milliliters of ethyl acetate was added, and the tube was closed and shaken for half a second. The stopper was removed, and the tube was centrifuged at 600 ϫ g for 10 min. The plug of debris along with the merthiolate-iodine-formalin solution was discarded by inverting the tube, leaving only the sediment, which was resuspended. The entire suspension was examined under a microscope. The total number of larvae in the sediment was counted and is presented as the number of larvae per gram of stool (lpg). A negative result meant that no larvae were seen in the whole sediment. This study protocol was approved by the Human Research Ethics Committee of Khon Kaen University.Of the 1,233 stool samples, 303 (24.57%) were found to be positive by at least one of the two meth...