Multiple diagnostic methods are established for identifying helminth infections

Diagnostic Techniques of Soil-Transmitted Helminths: Impact on Control Measures.. 2020. https://doi.org/10.3390/tropicalmed5020093

Soil-transmitted helminth (STH) infections are common in the tropical and subtropical countries. The burden of disease is highest in endemic areas with limited access to good quality water supply and poor sanitary conditions. Major approaches to control and reduce morbidity caused by worm infections include the periodic deworming of pre-school and school-aged children with anthelminthic drugs. Population-based studies and individual patient management including interventional studies can only be successful when accurate diagnostic techniques are used. The lack of appropriate diagnostic tools providing accurate results concerning both infectious status and intensity of infection-as these two factors vary in regions of low infection intensities-is a major challenge. Currently, available techniques show limited sensitivity and specificity and as such, a combination of several techniques is usually used to diagnose the large variety of parasite species. The objective of this review was to describe the advantages and disadvantages of the different available techniques for the diagnosis of STH infections and to highlight their use in control programs.

A Comparative Analysis of Microscopy, Coproantigen Serology, and Nested Multiplex PCR in the Laboratory Diagnosis of Entamoeba histolytica Infection. 2021. https://doi.org/10.1055/s-0041-1732488

Abstract Objectives Amoebiasis is caused by the most common intestinal protozoan parasite Entamoeba histolytica. This parasite causes amoebic colitis, which is manifested by diarrhea, followed by dysentery. The laboratory diagnosis of intestinal amoebiasis in most cases is by microscopic examination of stool samples. Other nonroutine methods include coproantigen enzyme-linked immunosorbent assay (ELISA) from stool samples, serum ELISA for antibodies, stool culture, isoenzyme analysis, and polymerase chain reaction (PCR). The present study aimed to comparatively analyze the different diagnostic modalities used for the detection of E. histolytica from the stool sample of patients with intestinal amoebiasis. Materials and Methods This study was undertaken with 631 patients, during a period of 3 years, from January 2017 to December 2019. Stool specimen obtained from each patient was subjected to direct microscopic wet mount examination, coproantigen ELISA, and nested multiplex PCR, respectively. Results Out of all the patients tested, 5.2% were positive for E. histolytica. Among the positive cases, stool microscopy was positive in 3.17%, coproantigen ELISA was positive in 29 (4.6%) cases, and PCR was positive in 30 (4.75%) cases. Statistical Analysis The prevalence of E. histolytica infection was summarized as percentages. The three diagnostic tests done were statistically analyzed, taking microscopy as the gold standard. The agreement between techniques (microscopy, coproantigen ELISA, and PCR) was analyzed with kappa statistics. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were summarized as percentage with 95% confidence interval. Conclusion In all suspected amoebiasis cases, a combination of stool microscopy, coproantigen testing with molecular detection of the parasite offers the best approach to diagnosis of this parasitic infection.

Molecular evidence of a high prevalence of Opisthorchis viverrini infection in an endemic community in Sakon Nakhon Province, northeastern Thailand.. 2026. https://doi.org/10.1186/s41182-026-00929-3

<h4>Background</h4>Opisthorchiasis caused by Opisthorchis viverrini infection is a major public health concern in Thailand. Despite decades of surveillance and control efforts, accurately estimating the true prevalence of O. viverrini remains a challenge. This study aimed to investigate the epidemiology of O. viverrini infection in an endemic community in northeastern Thailand using a combination of microscopic and molecular diagnostic methods.<h4>Methods</h4>A cross-sectional survey was conducted from May to July 2025 in Kusuman District, Sakon Nakhon Province. Demographic and behavioral data were collected using a standardized questionnaire. Stool samples were obtained from participants and examined using simple wet smear and modified Kato-Katz techniques to detect O. viverrini eggs and other intestinal parasites. In parallel, DNA was extracted from stool samples and polymerase chain reaction (PCR) targeting the internal transcribed spacer 2 (ITS2) gene was performed to confirm the presence of O. viverrini. Multiple logistic regression was used to investigate factors associated with infection.<h4>Results</h4>Among 246 participants, stool microscopy detected intestinal helminth infections in 10.2%, with O. viverrini being the most prevalent species (6.1%). Notably, all microscopy-positive O. viverrini cases were very light-intensity infections (< 500 eggs per gram [EPG] of stool). ITS2-specific PCR identified a higher prevalence of O. viverrini infection at 19.9%, detecting significantly more than three times as many cases as microscopy (P < 0.001). Multivariate regression analysis further showed that being male was associated with higher odds of O. viverrini infection (adjusted odds ratio [aOR] 5.55; 95% CI 2.41-12.83; P < 0.001), whereas participants aged 41-60 years had significantly lower odds compared to older individuals (aOR 0.08; 95% CI 0.03-0.19; P < 0.001).<h4>Conclusions</h4>This study demonstrates that O. viverrini infection remains highly prevalent in rural communities of northeast Thailand. Molecular diagnosis was more sensitive than conventional microscopy and key demographic risk factors were identified. These findings underscore the need for active surveillance and provide valuable data to guide and strengthen future prevention and control strategies for O. viverrini and other helminth infections in the region.