Correlation between Soil Transmitted Helminth Infection and Eosinophil Levels among Primary School Children in Medan

Association of Soil-Transmitted Helminths Infection with Total Serum Immunoglobulin E Levels and Total Eosinophils in Elementary School Students in Medan

BACKGROUND: Soil-transmitted helminths infection is widespread in tropical and subtropical areas. More than 267 million preschool-aged children and more than 568 million school-age children live in areas where this parasite is transmitted intensively and requires treatment and prevention. People at risk are preschool children, school-aged children, reproductive age women, and adults in certain high-risk occupations, such as tea pickers or miners. Worm infections often infect elementary schoolchildren because at this time, children have many activities and are often in direct contact with a dirty environment so that it can cause children not to pay attention to personal hygiene. AIM: This study aimed to determine the association of STH infection with total serum IgE levels and eosinophil counts in elementary school students in Medan. METHODS: This cross-sectional study was conducted on 65 elementary school students at Medan orphanage who met inclusion and exclusion criteria. Examination of STH infection was carried out using Kato-Katz method, and blood tests were performed to assess total serum IgE and blood eosinophils counts. Univariate and bivariate analysis was performed to determine the association of STH infection with total serum IgE levels and eosinophil counts in these students using Pearson correlation test and Chi-square. RESULTS: Of the 65 elementary school students in the orphanage who were willing to have their routine blood and feces checked, 36 boys (55.3%) and 29 girls (44.6%), 39 children were infected with STH (60%). The most common infections were Ascaris lumbricoides (26.1%), Trichuris trichiura (18.4%), and mixed infections (15.3%) with an average of mild infection intensity. The results of the analysis showed that there was no significant association between STH infection and eosinophils counts (p = 0.582, 95% confidence interval, OR 1.3). In addition, there was also no significant association of STH infection with total serum IgE levels (p = 0.883, 95% confidence interval, OR 63.6). CONCLUSION: In this study, there was no association between STH infection with eosinophils counts and total serum immunoglobulin E levels in elementary school students in Medan.

Nano Based Approach for the Treatment of Neglected Tropical Diseases

Neglected tropical diseases (NTDs) afflict more than one billion peoples in the world’s poorest countries. The World Health Organization (WHO) has recorded seventeen NTDs in its portfolio, mainly caused by bacterial, protozoal, parasitic, and viral infections. Each of the NTDs has its unique challenges on human health such as interventions for control, prevention, diagnosis, and treatment. Research for the development of new drug molecules against NTDs has not been undertaken by pharmaceutical industries due to high investment and low-returns, which results in limited chemotherapeutics in the market. In addition, conventional chemotherapies for the treatment of NTDs are unsatisfactory due to its low efficacy, increased drug resistance, short half-life, potential or harmful fatal toxic side effects, and drug incompetence to reach the site of parasite infection. In this context, active chemotherapies are considered to be re-formulated by overcoming these toxic side effects via a tissue-specific targeted drug delivery system. This review mainly emphasizes the recent developments of nanomaterial-based drug delivery systems for the effective treatment of NTDs especially sleeping sickness, leishmaniasis, chagas disease, soil-transmitted helminthiasis, african trypanosomiasis and dengue. Nanomaterials based drug delivery systems offer enhanced and effective alternative therapy through the re-formulation approach of conventional drugs into site-specific targeted delivery of drugs.

Burden of soil-transmitted helminth infection in pregnant refugees and migrants on the Thailand-Myanmar border: Results from a retrospective cohort

BACKGROUND

Soil-transmitted helminth (STH) infections are widespread in tropical and subtropical regions. While many STH infections are asymptomatic, vulnerable populations such as pregnant women face repercussions such as aggravation of maternal anaemia. However, data on prevalence and the effect of STH infections in pregnancy are limited. The aim of this analysis was to describe the burden of STH infections within and between populations of pregnant women from a local refugee camp to a mobile migrant population, and to explore possible associations between STH infection and pregnancy outcomes.

METHODOLOGY

This is a retrospective review of records from pregnant refugee and migrant women who attended Shoklo Malaria Research Unit antenatal care (ANC) clinics along the Thailand-Myanmar border between July 2013 and December 2017. Inclusion was based on provision of a stool sample during routine antenatal screening. A semi-quantitative formalin concentration method was employed for examination of faecal samples. The associations between STH mono-infections and maternal anaemia and pregnancy outcomes (i.e., miscarriage, stillbirth, preterm birth, and small for gestational age) were estimated using regression analysis.

PRINCIPAL FINDINGS

Overall, 12,742 pregnant women were included, of whom 2,702 (21.2%) had a confirmed infection with either Ascaris lumbricoides, hookworm, Trichuris trichiura, or a combination of these. The occurrence of STH infections in the refugee population (30.8%; 1,246/4,041) was higher than in the migrant population (16.7%; 1,456/8,701). A. lumbricoides was the predominant STH species in refugees and hookworm in migrants. A. lumbricoides and hookworm infection were associated with maternal anaemia at the first ANC consultation with adjusted odds ratios of 1.37 (95% confidence interval (CI) 1.08-1.72) and 1.65 (95% CI 1.19-2.24), respectively. Pregnant women with A. lumbricoides infection were less likely to miscarry when compared to women with negative stool samples (adjusted hazard ratio 0.63, 95% CI 0.48-0.84). STH infections were not significantly associated with stillbirth, preterm birth or being born too small for gestational age. One in five pregnant women in this cohort had STH infection. Association of STH infection with maternal anaemia, in particular in the event of late ANC enrolment, underlines the importance of early detection and treatment of STH infection. A potential protective effect of A. lumbricoides infection on miscarriage needs confirmation in prospective studies.

Prevalence and risk factors of soil-transmitted helminthiasis among school children living in an agricultural area of North Sumatera, Indonesia

BACKGROUND

Soil-transmitted helminth infection (STH) is one of the neglected tropical disease that affects approximately 2 billion people globally. School children represent the age group that is most commonly infected with STHs, resulting in poor school performance, impaired cognitive function, and many other detrimental effects. The transmission of STH is determined by many factors, such as hygiene and sanitation. Understanding the factors that influence disease transmission in a particular area is key to effective STH control. The objective of this study was to determine the prevalence of STH in North Sumatera and to identify the associated risk factors among school children.

METHODS

A cross-sectional study was carried out among primary school children in Suka village, Tigapanah subdistrict. Stool samples were processed using a single Kato-Katz method. The potential risk factors analyzed were parent education and occupation, hand washing habits, latrine usage, footwear usage and contact with soil. The Chi-square test was performed to identify an association between risk factors and parasitological results. Logistic regression analysis was used to measure the strength of association.

RESULTS

We enrolled 468 school children between 6 and 12 years of age. Among those children, 268 children (57.24%) were positive for one or more STH infections. Approximately 62.39% of children played with soil/dirt every day, and only 50% regularly washed their hands after activities. Most of the children wore shoes/slippers when going outside (87.82%) and used a latrine for defecation (85.04%). Playing with soil/dirt have been shown to increase the risk of STH infections 7.53 times, while hand washing habits and latrine usage decreased the risk of STH infections 0.16 times each.

CONCLUSION

The prevalence of STH infection in school children in Suka village, Tigapanah subdistrict is still high. Playing with soil/dirt increased the risk of infection, while hand washing habits and latrine usage decreased the risk of infection. The combined strategies of improving the personal hygiene of children and biannual deworming can reduce the risk of STH infection in school children in Suka village, Tigapanah subdistrict.

Robust Phenotypic Activation of Eosinophils during Experimental Toxocara canis Infection

Eosinophils are multifunctional cells that have cytotoxic proinflammatory activities and stimulate CD4⁺ T-cells in experimental models of allergy and parasitic infections. Eosinophils, when exposed to antigens, are activated, expressing the CD38/CD69 molecules and exhibited increased expression of major histocompatibility complex (MHC-II), CD80 and CD86, suggesting they play a role upon Toxocara canis antigen stimulation. In the present study, we evaluated the profile of eosinophils using conventional and image flow cytometry upon experimental T. canis infection. T. canis antigens induced a robust activation on this subset, contributing to the immune responses elicited in the experimental model for T. canis-associated visceral larva migrans syndrome. Data analysis demonstrated that, during murine T. canis infection, eosinophils from peripheral blood, spleen, and bone marrow presented upregulated expression of CD69/MHC-II/CD80/CD86. As opposed to splenic and bone marrow eosinophils, circulating eosinophils had increased expression of activation markers upon T. canis infection. The enhanced connectivity between eosinophils and T-cells in T. canis-infected mice in all three compartments (peripheral blood, spleen, and bone marrow) also supports the hypothesis that eosinophils may adopt a role during T. canis infection. Moreover, in vitro T. canis antigen stimulation resulted in activation and upregulation of co-stimulatory-related molecules by bone marrow-derived eosinophils. Our findings are evidence of activation and upregulation of important activation and co-stimulatory-related molecules in eosinophils and suggest a reshape of activation hierarchy toward eosinophils during experimental T. canis infection.