Evaluation of a Multiplex Bead Assay for Strongyloides stercoralis diagnosis using the recombinant antigen rSs-NIE-1.

A middle-aged woman was admitted to hospital several times in a period of six weeks where the underlying cause of her symptoms was related to a disease rarely seen in Norwegian hospitals. The patient was born and raised in Southeast Asia, but had lived in Norway since the 1970s. She was prescribed occasional courses of prednisolone for gout. The patient presented at hospital with abdominal pain. Examinations revealed gastrointestinal bleeding, metabolic acidosis and gram-negative sepsis. However, a ventricular biopsy revealed an underlying aetiology of Strongyloides stercoralis larvae. Strongyloidiasis is an infection caused by the intestinal nematode Strongyloides stercoralis. Transmission mainly occurs in tropical and subtropical areas, and the primary mode of infection is through larvae penetrating the skin. The parasite has a complex life cycle and, due to autoinfection, an infected person can have an active infection for several decades after leaving an endemic area. Subsequent impairment of host immunity can lead to accelerated autoinfection and cause hyperinfection, which could be fatal if left untreated. Before initiating immunosuppressive therapy, all patients should be considered for serological screening for strongyloidiasis, regardless of the time since possible exposure.

Community-based approaches have proven effective in improving early access to diagnosis for Chagas disease (CD). This study aimed to assess whether such strategies could reduce the number of patients lost to follow-up and contribute to the detection of concomitant Strongyloides stercoralis infection. The intervention was implemented at the Consulate General of Bolivia in Barcelona and began with awareness-raising activities about CD. The Public Health and Community team (eSPiC) subsequently offered on-site serological screening for CD, as well as diagnostic confirmation, antiparasitic treatment, and follow-up at the Drassanes-Vall d'Hebron International Health Unit (USIDVH). Of the 325 participants, 96.3% were adults of Bolivian origin residing in Catalonia, Spain. The mean age was 43 years, and 64.3% were women. Forty-two participants (13.5%) tested positive for CD and received a follow-up appointment. Of these, 22 (52%) attended the consultation; 10 (45.5%) completed antiparasitic treatment; 4 (18.2%) had been previously treated; 2 (9.1%) were not treated due to medical decision; and 6 (27.3%) were lost to follow-up. This study suggests that community-based follow-up strategies are advisable, particularly among middle-aged women with primary or secondary education. They facilitate a comprehensive continuum of care-from on-site screening to treatment adherence-which is essential for achieving the Chagas disease targets of the World Health Organization's Road Map for Neglected Tropical Diseases by 2030.

Strongyloides stercoralis in type 2 diabetes mellitus: discordant stool and serologic findings in an endemic Brazilian population.

Imported Strongyloides stercoralis infections in Germany: descriptive study of cases over 5 years in a referral center in Berlin.

Parasitic-induced Loeffler's syndrome: A systematic review based on clinical reports.

Long-term changes in weather conditions on Earth have a significant impact on the world around us. These include not only increasingly extreme weather events such as droughts and heatwaves. These effects can be felt throughout the natural environment, influencing the spread of parasites and the diseases they transmit. Climate change can alter the range and life cycles of parasites, and accelerate and lengthen the activity period of vectors. Four species are described in this manuscript: Balamuthia mandrillaris, Naegleria fowleri, Trypanosoma cruzi and Strongyloides stercoralis. Balamuthia mandrillaris is a species of an opportunistic cyst-forming free-living amoeba. The main habitat is moist soil and freshwater reservoirs. It could be pathogenic to humans. The amoeba consumes cutaneous tissue and excretes enzymes leading to an immune response of the host. Naegleria fowleri is a free-living amoeba that might cause primary amoebic meningoencephalitis (PAM) whose mortality rate reaches as much as 98%. Trophozoites enter the body through the nasal cavity while underwater. Most often cases of PAM include immunocompetent children and young adults. Trypanosoma cruzi is a flagellate protozoan with life cycle between hematophagous insects of the Triatominae subfamily and various mammal species including human. Trypanosoma cruzi causes the Chagas disease (American trypanosomiasis). Strongyloidiasis, caused by the parasite Strongyloides stercoralis, is a neglected tropical disease (NTD). Infection starts when the host walks barefoot on soil contaminated with filariform larvae that penetrate the skin. Immunosuppression in infected patients can lead to hiperinfection and death.

Knowledge of tropical parasitic infections, such as Strongyloides stercoralis, remains essential given increased migration from endemic areas and rising international travel. S. stercoralis can persist silently for decades and cause severe disease upon reactivation. We describe two illustrative cases. A 86-year-old former tropical physician developed eosinophilic pneumonia, skin lesions, and sensory ataxia. Symptoms persisted despite corticosteroid therapy but resolved rapidly after empirical ivermectin. In contrast, a 57-year-old Liberian man with prior immunosuppression presented with hyperinfection syndrome and died despite treatment. These cases highlight the need to consider parasitic infections even after long latency, especially in patients with a tropical history or immunosuppression. Timely recognition is crucial to prevent misdiagnosis and inadequate treatment. For accurate detection, serology or PCR-based diagnostics are preferred, as conventional stool microscopy often yields false-negative results due to the parasite's low and intermittent larval output. Empirical ivermectin should be considered in high-risk patients to prevent life-threatening complications.

Strongyloides stercoralis Parasitic Infection Manifesting as a Mass in the Ampulla of Vater: A Rare Case Presentation

Background & objectives: Hookworm infection is one of the important causes of iron deficiency anaemia in children. Sensitive diagnostic methods are important for accurate assessment among the different species of hookworm infection. Microscopy is still gold standared however microscopy alone cannot differentiate between hookworm species and other similar Strongyloid. Objective: The objective of this study is to identify the hookworm eggs from the stool sample by microscopy and further subjected for species specific identification targeting mitochondrial cytochrome oxidase I gene. Methods: A total methods of 300 samples were collected from the children with gastrointestinal symptoms during February 2018 to February 2019.All samples were examined using saline and iodine mount preparation and further subjected to different culture techniques and conventional PCR.Stoll dilution eggs counts technique was used to identify the intensity of the hookworm positive samples Results: Stool samples with intestinal parasites detected in this study were 70/300;out of which 20 samples was hookworm positive by microscopy. Sixteen out of 20 were identified as Necator americanus and 2 samples each were identified as Anylostoma duodenale and Strongyloides stercoralis. There were no mixed infections in this study. Stoll’s dilution egg count showed moderate infection in 66.6%, light and heavy infection in 16.7%. Diarrhea accompanied with dehydration, weakness, fever, bloating was the most common complained associated (6.6%) among the hookworm positive children. Interpretation & Conclusion: The highest infection was seen in 6-10 years and more common in males (p=0.7648).Species identification of hookworm targeting COX I gene is rapid and sensitive for accurate identification for the hookworm species in the limited resource setting area like Sikkim.

Hammerhead ribozymes have found extensive applications in gene expression regulation across diverse biological systems including Escherichia coli, yeast, plants, and mammalian cells. However, their implementation in parasitic nematodes remains unexplored. Strongyloides stercoralis emerges as a particularly valuable model organism for studying developmental transitions in parasitic nematodes due to its unique life cycle alternating between parasitic and free-living stages. To expand the experimental toolkit for investigating developmental, evolutionary, and behavioral processes in this species, we established a conditional gene regulation system through transgenic integration of synthetic ribozyme constructs and demonstrated efficacy in regulating both exogenous (mrfp) and endogenous (unc-22) gene expression through targeted RNA processing mechanisms. Focusing on the insulin/IGF-1 signaling pathway, a critical regulator of parasitic nematode development and longevity, we implemented ribozyme-mediated post-transcriptional control to dissect functional divergence between two isoforms of the insulin receptor homolog Ss-DAF-2. Comparative analysis revealed isoform-specific characteristics: while both isoforms maintain conserved signaling functions, isoform B exhibits specific binding affinity for human insulin and demonstrates significant transcriptional upregulation during parasitic transition phases. This ligand selectivity profile suggests that isoform B may serve as a molecular interface for host-derived insulin signaling coordination during parasitism. This study established a programmable ribozyme tool in S. stercoralis, functionally discriminated the two Ss-DAF-2 isoforms through precision RNA engineering, and identified isoform-specific ligand preferences with implications for host-parasite signaling. Our findings not only validate ribozyme-based approaches for genetic manipulation in parasitic nematodes but also lay the groundwork for future implementation of synthetic RNA switches in helminth research.

Strongyloidiasis is a disease caused by the soil-transmitted nematode Strongyloides stercoralis. It is considered a neglected disease that can lead to long-term disability, growth retardation in children, complications during pregnancy, and adverse effects on the fetus. In the present case report, we examined a case of strongyloidiasis in a newborn born to a mother with confirmed strongyloidiasis during pregnancy, diagnosed by serological, parasitological, and molecular methods. A 38-year-old woman at 35 weeks of gestation from a rural area in Rasht, Guilan Province, Iran, presented with gastrointestinal symptoms (diarrhea, abdominal pain) and severe dyspnea since the fourth month of pregnancy. Her medical history included hypothyroidism and a pituitary microadenoma. Laboratory findings revealed a peripheral blood eosinophil count of 2%. Stool examination (direct smear, formalin-ethyl acetate concentration, and agar plate culture) and serological testing (ELISA for S. stercoralis antibodies) confirmed strongyloidiasis, further validated by molecular methods. Due to potential risks of anti-helminthic drugs during pregnancy, treatment was deferred until one month post-delivery, after breastfeeding cessation. The newborn’s stool and breast milk were tested parasitologically and molecularly one month after birth, with negative results, indicating no infection. Although mother-to-fetus transmission has not been definitively established, the fetus is considered a high-risk group. Pregnant women, due to their immunocompromised state, are also classified as a high-risk population and may develop disseminated strongyloidiasis or hyperinfection syndrome. Given the adverse effects of antiparasitic treatment during pregnancy, routine serological screening for S. stercoralis in women before pregnancy in endemic areas is recommended to enable early intervention and mitigate complications, safeguarding maternal and fetal health.

Aim: Parasitic infections caused by intestinal helminthes and protozoan parasites are among the most prevalent infections in humans in developing countries and cause significant morbidity and mortality. It have been reported by various authors that Parasitic infections caused by intestinal helminthes and protozoan parasites cause significant morbidity and mortality, iron deficiency anaemia, growth retardation in children and other physical mental health problems in endemic areas. No comprehensive study has been conducted to elucidate nutritional status, prevalence of intestinal parasites in Gombe State. In view of this therefore, the aim of the study is to assess the prevalence of intestinal parasitic infections and their associated risk factors among children in Gombe State. Study Design: A cross-sectional study was conducted to determine the prevalence of intestinal parasitic infections (IPIs) among school children in Gombe State, Nigeria. Six Local Governments (2 from each Zone) were selected using simple random sampling method. Place and Duration of Study: the study was carried out at Microbiology Laboratory. Federal Teaching Hospital Gombe. Between June 2023 and July 2024. Methodology: A total of 1200 school children were included for the study (569 male, 631 female; age range 5-14 years) Faecal samples were examined using direct wet mount method and Formol-Ether Concentration techniques, Structured questionnaire based on known risk factors was used to assess the risk factors associated with intestinal parasitic infections. Results: Total prevalence of 26.75% was recorded in the study areas with Ascaris lumbricoides (10.5%), Entamoeba coli (3.5%), Hookworm (1.91%), H. nana (1.75%), Entamoeba histolytica (1.75%), Taenia saginata(1.66%), Trichuris trichiura (1.58%), Giardia lamblia (1.38%), E. vermicularis (1.0%), Strongyloides stercoralis (0.91%) and Schistosoma mansoni (0.75%). There was statistically significant association between sex, age group, location and the intestinal parasitic infections. Prevalence of co-infection was 14.0%. Hand washing before eating was found to be significantly associated with parasitic infection. (p<0.05) Conclusion: Improved sanitation and more deworming efforts should be sustained to ensure further decline in prevalence of intestinal parasitic infections.

Infection with the soil-transmitted helminth Strongyloides stercoralis is typically asymptomatic but can result in life-threatening hyperinfection syndrome in immunocompromised individuals. To improve serological tests for strongyloidiasis, we evaluated the Ss-IR antigen using a multiplex bead assay and compared this assay to the commonly used Ss-NIE antigen. We assessed assay sensitivity and specificity using the following serum panels: sera from United States–bound refugees (57 positive stool polymerase chain reaction [PCR], 88 negative PCR) departing from Thailand-Burma border camps (panel 1); sera from individuals from Argentina with stool PCR confirmed S. stercoralis (panel 2, n = 50); and presumed negatives from the United States with no travel history (panel 3, n = 185). The Ss-IR antigen demonstrated sensitivities of 90.0% and 89.5% and specificities of 98.9% and 89.8% in panels 1, and panels 2 and 3, respectively. When compared with Ss-NIE, the Ss-IR antigen demonstrated superior sensitivity, area under the curve, and reproducibility than Ss-NIE, supporting more extensive validation for surveillance use.

Serological screening for toxocariasis, strongyloidiasis and fascioliasis in individuals with eosinophilia in Khuzestan, Iran.

ABSTRACT Soil-transmitted helminths (STH) are common in (sub)tropical regions and primarily affect impoverished populations. These parasites reside in the gut, where they interact with both the microbiota and host immunity. Clinical STH detection is laborious and often not performed within the context of gut microbiome studies. Here, we present a proof-of-concept study assessing whether fecal metagenome data could be used to assess STH infection, and to relate STH infection to microbiome features. We leveraged 310 gut metagenomes obtained from mother-child pairs in two different locations in Gabon: one rural and one semi-urban, and assessed the presence of four STH species (Ascaris lumbricoides, Strongyloides stercoralis, Trichuris trichiura, and Necator americanus) using qPCR. Sequence data were used to characterize the microbiomes and to detect these parasites. Metagenomic read mapping and genome coverage metrics closely matched qPCR detection patterns. Within-location analyses revealed that parasite species richness was associated with microbiome diversity and taxonomic composition, with the strongest associations observed in children from the rural site. Applying this approach to published data from five additional African cohorts identified context-specific parasite-microbiome associations, as well as a modest but reproducible association between microbiome alpha diversity and parasite infection. These findings highlight the potential of shotgun metagenomics for concurrent parasite detection and microbiome profiling across diverse geographic and demographic contexts.

Strongyloides stercoralis infection affects approximately 600 million individuals worldwide. This parasite has the ability to exacerbate infection through internal autoinfection, which can lead to hyperinfection and/or dissemination, conditions associated with high morbidity and mortality, particularly in immunocompromised patients such as those with alcohol use disorder (AUD). In this study, we conducted a meta-analysis to assess the prevalence and risk of having S. stercoralis infection among individuals with AUD. Searches were performed in the PubMed, Embase, and LILACS databases to identify studies investigating the prevalence of S. stercoralis infection in individuals with AUD, with or without comparison to non-alcoholic groups. The pooled prevalence was calculated using the Probit Logit (PLOGIT) transformation, and the odds ratio (OR) was used for risk comparison. The initial search yielded 154 studies, of which seven were included in the systematic review and meta-analysis. The combined prevalence of S. stercoralis infection among patients with AUD was 16.9%. Risk analysis based on four studies showed that individuals with AUD had a 6.08-fold higher risk of infection compared with non-alcoholic individuals. These findings highlight chronic alcoholism as a significant risk factor for strongyloidiasis, likely due to a combination of environmental, physiological, and immunological factors. This meta-analysis underscores the critical need for routine screening for S. stercoralis infection in patients with AUD, even in the absence of clinical symptoms, to ensure early detection and timely intervention.

The infection burden of Strongyloides stercoralis in India remains poorly defined. We aimed to estimate the burden of S. stercoralis infection among immunocompromised patients at our tertiary care hospital in north India and evaluated the performance of multiple diagnostic tests. Paired stool and blood samples were collected from 498 immunosuppressed individuals. Screening included stool microscopy without concentration, Baermann’s funnel method, Agar plate and Harada Mori cultures, 18S ribosomal RNA gene real-time polymerase chain reaction (RT-PCR), and anti- Strongyloides IgG antibody ELISA. Bayesian latent class analysis (BLCA) was performed to estimate diagnostic accuracy without assuming a gold standard. Overall, 16.9% ( n = 84/498) of immunosuppressed individuals were positive by a composite reference standard, most commonly detected by a combination of ELISA and RT-PCR. Among single tests, BLCA estimated ELISA sensitivity of 74.5% (95% credible interval [CrI]: 62.7–84.5) and specificity of 88.3% (95% CrI: 85.4–90.9). Culture and RT-PCR showed sensitivities of 62.9% (95% CrI: 50.0–75.1) and 62.6% (95% CrI: 50.2–74.6) and specificities of 99.8% (95% CrI: 99.4–100.0) and 95.5% (95% CrI: 93.6–97.2), respectively. ELISA plus RT-PCR demonstrated the best performance with 87.5% (95% CrI: 76.9–95.0) sensitivity and (89.0%, 95% CrI: 83.4–94.7) specificity. Strongyloides stercoralis infection was most frequent among patients with hypereosinophilia syndromes (33.3%), and increasing absolute eosinophilia count independently predicted infection. This study highlights a high burden of S. stercoralis infection in immunocompromised patients in north India and underscores the utility of combining serological and molecular assays for optimal detection in high-risk populations.

The purpose of this study was to determine the effects of geohelminths on academic performance of school children living in slums of Nairobi County, Kenya. A longitudinal study was carried out in children aged 6-18 years in classes 2-7 from schools within 2 slums in Nairobi County. Household socio-economic status questionnaires were administered to cater for potential confounders. Stools were collected and analyzed by modified Ridley and Kato-Katz Thick Stool Smear techniques. Infection intensity was defined by World Health Organization criteria and 3 terms pre- and 2 terms post-treatment academic records were collected for analysis; data were coded and entered in the Microsoft Excel. Data was analyzed using Statistical Analysis Software, Version 9.4 M8 (2023) for descriptive statistics and Analysis of variance (ANOVA); t-test was used to detect significant differences in pre-treatment, post-treatment academic performance. Pearsons Product Moment Correlation analysis was used to show associations between intensity of geohelminthiases and academic performance. The highest prevalence occurred with Ascaris lumbricoides (37.4%) and Trichuris trichiura (33.2%). Highest number of light and moderate infections (16.5%) and (10.4%), respectively, occurred in 11-14 years age-group, pre-treatment. No Strongyloides stercoralis larvae were seen in stools. There was significant difference in infection intensities with T. trichiura and A. lumbricoides between males and females, p < 0.05, with females having higher infections. Geohelminthiases adversely affected Academic performance) r = - 0.879; p<0.05). Treatment with albendazole was more effective with A. lumbricoides than T. trichura. We recommend that effective control of geohelminths required periodic, regular mass deworming with benzimindazoles (broad-spectrum athelminthics). In addition, stake holders need to be properly informed on the importance of maintaining proper environmental sanitation and effective health education campaign strategies.

Strongyloides stercoralis, a soil-transmitted parasitic helminth, poses significant health risks for various species, including humans and canines. Despite previously being considered rare in Australia, recent findings indicate a higher than anticipated prevalence, suggesting it might be an underdiagnosed issue nationwide. This case report details a deceased 23-week-old female Boston Terrier that presented with severe gastrointestinal signs and died, despite intensive veterinary care. Subsequent histopathological and parasitological examinations confirmed a significant infestation of S. stercoralis, with severe intestinal damage typical of strongyloidiasis. This case underscores the capacity of S. stercoralis to cause severe disease and highlights the importance of considering strongyloidiasis in the differential diagnoses of gastrointestinal illness.