Prevention of Soil-transmitted Helminth Infection

Prevalence and associated risk factors of soil-transmitted helminth infections among schoolchildren in Mekan Eyesus town, northwestern Ethiopia

Background

Little attention has been paid to determining the prevalence and associated factors of soil-transmitted helminth (STH) infections in some developing countries. This study was, therefore, carried out to determine the prevalence and associated factors of STH infections among schoolchildren attending three primary schools in Mekane Eyesus town, northwestern Ethiopia.

Methods

A school-based cross-sectional study was conducted from March to June 2023 in Mekane Eyesus town. Stool samples were collected from 401 children from three primary schools in the town. Wet-mount and formol ether concentration techniques were used to diagnose stool samples, and a structured questionnaire was used to collect data on socio-demographic characteristics and risk factors for STH infections.

Results

The overall prevalence of STH infection in this study was 18.2 % (73/401). The most common helminth species detected was Ascaris lumbricoides (A. lumbricoides) (7.5 % (30/401)). Not trimming fingernails regularly (adjusted odds ratio (AOR) = 3.75, 95 % CI = 1.87-7.50), having illiterate fathers (AOR = 2.29, 95 % CI = 1.18-4.44), and being aged 15-17 years (AOR = 2.37, 95 % CI = 1.06-5.30) were associated with increased odds of STH infection. Children who wash their hands after defecation (AOR = 0.43, 95 % CI = 0.21-0.88) and those whose mothers were housewives (AOR = 0.22, 95 % CI = 0.08-0.58) had lower odds of STH infection.

Conclusion

This study found a high prevalence of STH infection among schoolchildren in Mekane Eyesus town. Thus, STH infection preventive measures, including deworming of schoolchildren, should be implemented in the study area. Moreover, giving health-related knowledge about STH infection prevention strategies, such as regular fingernail trimming and hand washing after defecating, is vital for reducing the prevalence of STH infections in the study area.

High prevalence of soil-transmitted helminths and schistosomiasis among primary schoolchildren in Southwest Ethiopia: the need for health strategies alongside mass drug administration

BACKGROUND

Soil-transmitted helminths (STH) and schistosomiasis remain widely prevalent in Ethiopia. The aim of this study was to evaluate the prevalence of STH and schistosomiasis among schoolchildren in Gidi Bench district (Southern Nations, Nationalities, and People's Republic, Southwest Ethiopia) and the association with knowledge and health-related behaviors.

METHODS

A cross-sectional study was conducted. Stool samples, analyzed by the Kato-Katz technique and a knowledge, attitudes and practices questionnaire, were collected.

RESULTS

Out of 611 participants (mean age 12.8±3.1 y), 129 (21.1%) were infected with schistosomiasis and 382 (62.5%) had STH. More than 30% (n=195, 31.9%) were infected with a single intestinal parasite, while 138 (22.6%) and 47 (7.7%) were infected with two or three parasitic infections, respectively. Boys and those who did not participate in school clubs had higher infection rates (p=0.05). Lower parasitic infection was associated with using a latrine when available, washing hands and vegetables and wearing shoes regularly. Higher rates of infection were found among those who reported swimming and washing cloths and utensils in the river regularly.

CONCLUSIONS

Schistosomiasis and STH were highly prevalent among schoolchildren in Gidi Bench district. Infection rates were associated with gender, lack of knowledge on parasitic infections and unhealthy behaviors. Findings from this study may assist in decision making regarding disease prevalence and methods of control alongside mass drug administration.

Correlating Cases of Soil-Transmitted Helminths and Remote Sensing Covariates: A Case Study Utilizing 2015, 2017, and 2019 Metadata of Camarines Sur, Philippines

INTRODUCTION

Soil-transmitted helminth (STH) is a group of helminths that are considered to be neglected tropical diseases (NTDs) and, globally, affect more than 1.5 to 2.6 million people yearly. Depending on the species, they can be acquired by ingesting embryonated eggs from contaminated matter or by skin penetration. Most species of STH are found in the tropics, such as the Philippines. Despite the Mass Drug Administration (MDA), the cases of STH infection continue to rise in the country. Surveys from the Research Institute of Tropical Medicine (RITM) indicate that a high prevalence of STH (Ascaris lumbricoides, Trichuris trichiura, and Necator americanus) was primarily observed in the provinces of the country, such as in Camarines Sur.

OBJECTIVES

To correlate remote sensing covariates such as Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built-up Index (NDBI) - to STH-infected cases of the 37 municipalities of Camarines Sur.

METHODOLOGY

The available public health record of STH cases from 2015 to 2019 were calculated using the Quantum Geographic Information System (QGIS)and correlated using Pearson Correlation Coefficient.

RESULTS

The results showed that infection was higher in children than adults, and A. lumbricoides caused 60% of infection. No correlation of indices with infection cases during 2015 and 2017 was observed; however, 2019 showed a moderate strength (p = 0.037) in correlation.

CONCLUSION

This indicates that infection relied not mainly on vegetation and urbanization but on additional environmental factors and non-environmental variables.

Soil-transmitted Helminth Infection and Perinatal Outcomes in Pregnant Women in Primary Care Settings in South India: A Cohort Study

Background

Soil-transmitted helminth infections (STHs) in pregnancy have been linked to maternal anemia, low birth weight, and adverse perinatal outcomes. STH includes Ascaris lumbricoides, hookworm, and Trichuris trichiura. However, conflicting evidence exists regarding these effects. Hence, we aimed to assess the association of STH infections with perinatal outcomes.

Methods and Materials

A community-based cohort study was conducted among pregnant women in primary care settings in Puducherry, South India, during December 2019 to April 2021. Stool samples were collected for STH screening and confirmed using polymerase chain reaction. Information on perinatal outcomes and hemoglobin levels were extracted from case records. The association of pre-term birth, low birth weight, anemia, and miscarriages with STH infection was analyzed using the Chi-square test.

Results

Among the 650 women enrolled, 58 (8.9%) had one of the STH infections. At the time of recruitment, 336 (52.0%) women had anemia. Twenty-four women (3.7%) had miscarriages, 14 (2.2%) had pre-term birth, and 65 (10.4%) had low-birth-weight (LBW) babies. All 14 pre-term babies had LBW, and out of 65 LBW, 40 were in mothers with anemia. Incidence of LBW, pre-term deliveries, and anemia were higher in women with STH than in those without STH (LBW: 12.3% vs 10.2%, P = 0.62; pre-term: 3.5% vs 2.1%, P = 0.5; and anemia: 54.4% vs 51.85, P = 0.7).

Conclusion

Though the incidence of anemia, LBW, and pre-term delivery was higher in women with STH infections compared to those without STH, we did not find any significant association between the presence of STH infections and perinatal outcomes.

A four-year assessment of the characteristics of Rwandan FDA drug recalls

BACKGROUND

A drug recall is an act of removing products from the market and/or returning them to the manufacturer for disposal or correction when they violate safety laws. Action can be initiated by the manufacturing company or by the order of a regulatory body. This study aimed to assess the characteristics of Rwanda FDA drug recall and determine the association between classes of recall and recall characteristics.

METHODOLOGY

This was a retrospective descriptive cross-sectional study. Data about recalled drugs were collected from the official website of the Rwanda FDA in the section assigned to "Safety alerts". The search included data reported between February 2019 and February 2023 covering four years. Data cleaning was conducted in Microsoft Excel to address missing data and inconsistencies, followed by importation into STATA/SE software version 17.0 for further cleaning and subsequent analysis. Descriptive statistics were computed for independent variables. Categorical variables were described in terms of counts and relative frequencies. Bivariate analyses used Pearson's chi-square test to illustrate the associations between categorical independent variables and recall classes.

RESULTS

The study revealed that a large proportion (33.0%) of the recalled products belonged to Class I. Antibiotics constituted 35.8% of the recalled products, with contamination emerging as a leading cause and responsible for 26.4% of the recalls. India was the leading manufacturing country for the recalled products (29.2%), followed by France (17.9%), China (17.0%), Kenya (13.2%), and Russia (6.6%). An association was found between the class of recall and several recall characteristics, including the year of recall, drug category, safety issues, reporter, and manufacturing country.

CONCLUSION

This study provides a comprehensive overview of the characteristics of drug recalls in Rwanda. The insights gained contribute to a nuanced understanding of recall dynamics and provide evidence-based strategies to enhance drug quality, safety, efficacy, regulatory compliance, and patient welfare.

An update on the current and emerging pharmacotherapy for the treatment of human ascariasis

INTRODUCTION

Globally, Ascaris lumbricoides is the commonest helminthic infection that affects people in underdeveloped countries and returning immigrants in industrialized nations. This article aims to provide latest updates on the epidemiology, clinical manifestations, and pharmacotherapy of ascariasis.

AREAS COVERED

A PubMed search was conducted using Clinical Queries and the key terms 'human ascariasis' OR 'Ascaris lumbricoides.' Ascaris lumbricoides is highly endemic in tropical and subtropic regions and among returning immigrants in industrialized nations. Predisposing factors include poor sanitation and poverty. The prevalence is greatest in young children. Most infected patients are asymptomatic. Patients with A. lumbricoides infection should be treated with anti-helminthic drugs to prevent complications from migration of the worm. Mebendazole and albendazole are indicated for children and nonpregnant women. Pregnant individuals should be treated with pyrantel pamoate.

EXPERT OPINION

Cure rates with anthelmintic treatment are high. No emerging pharmacotherapy can replace these existing drugs of good efficacy, safety profile and low cost for public health. It is opinioned that advances in the management of ascariasis include diagnostic accuracy at affordable costs, Emodepside is highly effective in single doses against ascarids in mammals and in human trials. The drug could be registered for human use in multiple neglected tropical diseases.

Strongyloidiasis

Strongyloidiasis is a neglected tropical disease caused primarily by the roundworm Strongyloides stercoralis. Strongyloidiasis is most prevalent in Southeast Asia and the Western Pacific. Although cases have been documented worldwide, global prevalence is largely unknown due to limited surveillance. Infection of the definitive human host occurs via direct skin penetration of the infective filariform larvae. Parasitic females reside in the small intestine and reproduce via parthenogenesis, where eggs hatch inside the host before rhabditiform larvae are excreted in faeces to begin the single generation free-living life cycle. Rhabditiform larvae can also develop directly into infectious filariform larvae in the gut and cause autoinfection. Although many are asymptomatic, infected individuals may report a range of non-specific gastrointestinal, respiratory or skin symptoms. Autoinfection may cause hyperinfection and disseminated strongyloidiasis in immunocompromised individuals, which is often fatal. Diagnosis requires direct examination of larvae in clinical specimens, positive serology or nucleic acid detection. However, there is a lack of standardization of techniques for all diagnostic types. Ivermectin is the treatment of choice. Control and elimination of strongyloidiasis will require a multifaceted, integrated approach, including highly sensitive and standardized diagnostics, active surveillance, health information, education and communication strategies, improved water, sanitation and hygiene, access to efficacious treatment, vaccine development and better integration and acknowledgement in current helminth control programmes.

K, Baral A, Shrestha R, Shrestha R. Cutaneous larva migrans in a child: a case report and review of literature

Introduction

Cutaneous larva migrans (CLM) is a dermatitis caused by the invasion and migration of parasitic larvae of hookworms, primarily affecting tropical and subtropical regions. This report presents a case of CLM in a Nepali child and provides an overview of the literature on this condition.

Case report

A 4-year-old boy from a rural area in Nepal presented with a pruritic skin lesion on his left foot, initially misdiagnosed as fungal infection. The lesion gradually expanded, forming a serpiginous erythema, and became intensely pruritic. The patient's family had poor socioeconomic conditions, and the child frequently walked barefoot in an area with many domestic and stray dogs. Diagnosis was confirmed clinically, and treatment with oral albendazole and antihistamines resulted in complete resolution of symptoms.

Discussion

CLM is a neglected zoonotic disease, with an underestimated burden in developing countries due to underreporting and misdiagnosis. The larvae of Ancylostoma spp. are common culprits, causing a localized inflammatory reaction as they migrate through the skin. Diagnosis is mainly clinical and routine investigations usually reveal no abnormality. Complications may include secondary bacterial infections, allergies, and rare migration to internal organs. Treatment options include albendazole or ivermectin, with preventive measures emphasizing hygiene, footwear use, and pet deworming.

Conclusion

CLM is a neglected disease that primarily affects marginalized communities in tropical regions. Raising awareness among healthcare providers, conducting observational studies, and developing treatment guidelines, especially for children, are essential steps to address this public health concern. Preventive efforts, such as promoting hygiene and footwear use, should be encouraged to reduce CLM incidence.

Implications of the prevalence of Ascaris sp. in the funerary context of a Late Antique population (5th-7th c.) in Granada (Spain)

OBJECTIVE

To evaluate the prevalence of gastro-intestinal parasites in human remains from Late Antiquity (5th - 7th c.) Granada (Spain).

MATERIALS

The study included pelvic and cranial control samples from 17 skeletons from the archaeological sites of Los Mondragones (n = 13) and Rafael Guillén (n = 4).

METHODS

In the paleoparasitological study, soil samples from pelvic area and cranium were analyzed using the rehydration, homogenization, and micro-sieving method and visualization under brightfield microscopy.

RESULTS

Ascaris sp. eggs were detected in pelvic samples from seven individuals.

CONCLUSIONS

These findings may indicate that this parasite was endemic. Its detection frequency is one of the highest reported at group level in an osteological series from Late Antiquity.

SIGNIFICANCE

The prevalence of Ascaris sp. associated with skeletal remains has implications for assessing the lifestyle and health of populations in southern Spain during the Late Antique period.

LIMITATIONS

The number of individuals is small and taphonomic processes could have limited paleoparasitological findings SUGGESTIONS FOR FURTHER RESEARCH: Future interdisciplinary studies of this type are warranted in larger osteological series to improve knowledge of parasitosis in the past.

Singab A. Botanicals against some important nematodal diseases: Ascariasis and hookworm infections

Ascariasis and intestinal parasitic nematodes are the leading cause of mass mortality infecting many people across the globe. In light of the various deleterious side effects of modern chemical-based allopathic drugs, our preferences have currently shifted towards the use of traditional plant-based drugs or botanicals for treating diseases. The defensive propensities in the botanicals against parasites have probably evolved during their co-habitation with parasites, humans and plants in nature and hence their combative interference in one another's defensive mechanisms has occurred naturally ultimately being very effective in treating diseases. This article broadly outlines the utility of plant-based compounds or botanicals prepared from various medicinal herbs that have the potential to be developed as effective therapies against the important parasites causing ascariasis and intestinal hookworm infections leading to ascariasis & infections and thereby human mortality, wherein allopathic treatments are less effective and causes enormous side-effects.

Traditional medicinal plants in the treatment of gastrointestinal parasites in humans: A systematic review and meta-analysis of clinical and experimental evidence

Gastrointestinal (GI) parasites cause significant morbidity and mortality worldwide. The use of conventional antiparasitic drugs is often inhibited due to limited availability, side effects or parasite resistance. Medicinal plants can be used as alternatives or adjuncts to current antiparasitic therapies. This systematic review and meta-analysis aimed to critically synthesise the literature on the efficacy of different plants and plant compounds against common human GI parasites and their toxicity profiles. Searches were conducted from inception to September 2021. Of 5393 screened articles, 162 were included in the qualitative synthesis (159 experimental studies and three randomised control trials [RCTs]), and three articles were included in meta-analyses. A total of 507 plant species belonging to 126 families were tested against different parasites, and most of these (78.4%) evaluated antiparasitic efficacy in vitro. A total of 91 plant species and 34 compounds were reported as having significant in vitro efficacy against parasites. Only a few plants (n = 57) were evaluated for their toxicity before testing their antiparasitic effects. The meta-analyses revealed strong evidence of the effectiveness of Lepidium virginicum L. against Entamoeba histolytica with a pooled mean IC50 of 198.63 μg/mL (95% CI 155.54-241.72). We present summary tables and various recommendations to direct future research.

Medicinal plants as a source of antiparasitics: an overview of experimental studies

Despite advances in modern human and veterinary medicine, gastrointestinal (GI) parasitic infections remain a significant health issue worldwide, mainly in developing countries. Increasing evidence of the multi-drug resistance of these parasites and the side effects of currently available synthetic drugs have led to increased research on alternative medicines to treat parasitic infections. The exploration of potential botanical antiparasitics, which are inexpensive and abundant, may be a promising alternative in this context. This study summarizes the in vitro/in vivo antiparasitic efficacy of different medicinal plants and their components against GI parasites. Published literature from 1990-2020 was retrieved from Google Scholar, Web of Science, PubMed and Scopus. A total of 68 plant species belonging to 32 families have been evaluated as antiparasitic agents against GI parasites worldwide. The majority of studies (70%) were conducted in vitro. Most plants were from the Fabaceae family (53%, n = 18). Methanol (37%, n = 35) was the most used solvent. Leaf (22%, n = 16) was the most used plant part, followed by seed and rhizome (each 12%, n = 9). These studies suggest that herbal medicines hold a great scope for new drug discoveries against parasitic diseases and that the derivatives of these plants are useful structures for drug synthesis and bioactivity optimization.

Soil-transmitted helminths: A critical review of the impact of co-infections and implications for control and elimination

Researchers have raised the possibility that soil-transmitted helminth (STH) infections might modify the host's immune response against other systemic infections. STH infections can alter the immune response towards type 2 immunity that could then affect the likelihood and severity of other illnesses. However, the importance of co-infections is not completely understood, and the impact and direction of their effects vary considerably by infection. This review synthesizes evidence regarding the relevance of STH co-infections, the potential mechanisms that explain their effects, and how they might affect control and elimination efforts. According to the literature reviewed, there are both positive and negative effects associated with STH infections on other diseases such as malaria, human immunodeficiency virus (HIV), tuberculosis, gestational anemia, pediatric anemia, neglected tropical diseases (NTDs) like lymphatic filariasis, onchocerciasis, schistosomiasis, and trachoma, as well as Coronavirus Disease 2019 (COVID-19) and human papillomavirus (HPV). Studies typically describe how STHs can affect the immune system and promote increased susceptibility, survival, and persistence of the infection in the host by causing a TH2-dominated immune response. The co-infection of STH with other diseases has important implications for the development of treatment and control strategies. Eliminating parasites from a human host can be more challenging because the TH2-dominated immune response induced by STH infection can suppress the TH1 immune response required to control other infections, resulting in an increased pathogen load and more severe disease. Preventive chemotherapy and treatment are currently the most common approaches used for the control of STH infections, but these approaches alone may not be adequate to achieve elimination goals. Based on the conclusions drawn from this review, integrated approaches that combine drug administration with water, sanitation and hygiene (WASH) interventions, hygiene education, community engagement, and vaccines are most likely to succeed in interrupting the transmission of STH co-infections. Gaining a better understanding of the behavior and relevance of STH co-infections in the context of elimination efforts is an important intermediate step toward reducing the associated burden of disease.

Community perception of school-based mass drug administration program for soil-transmitted helminths and Schistosomiasis in Ogun State, Nigeria

BACKGROUND

Neglected tropical diseases, such as soil-transmitted helminths and Schistosomiasis, are prevalent in sub-Saharan Africa, particularly Ogun State, Nigeria. School-based mass drug administration program is the primary control intervention, but the coverage and uptake of this intervention have been inadequate. This study aimed to investigate community perceptions of school-based mass drug administration programs for these infections in Ogun State, Nigeria, and identify the barriers to their uptake and coverage.

METHODOLOGY/PRINCIPAL FINDINGS

The study used a qualitative research approach involving focus group discussions and in-depth interviews with community members and stakeholders engaged in neglected tropical disease control programs in Ogun State, Nigeria. A semi-structured questionnaire guided the exploration of ideas, and the data were analyzed using the QRS Nvivo 12 software package. The study found several barriers, such as the influence of parents, lack of sufficient knowledge, and side effects. The study recommended strategies such as improving community sensitization and engagement, drug distribution and performance, and enhancing partner collaboration and coordination to improve the school-based mass drug administration programs.

CONCLUSIONS/SIGNIFICANCE

The study revealed correct perceptions of transmission but some misconceptions about disease causation, transmission, and drug safety. Participants expressed a desire for better sensitization campaigns and more assurances of their safety. The study recommends strengthening health education messages and increasing the visibility of on-site medical personnel. The findings have implications for improving the performance of these programs and reducing the burden of intestinal parasitic infections in the community. The study highlights the need for community engagement and education, health system support, and partner collaboration to successfully implement mass drug administration programs.

Nutritional status of under-five aged children of ready-made garment workers in Bangladesh: A cross-sectional study

BACKGROUND

The ready-made garment (RMG) sector is a significant contributor to the economic growth of Bangladesh, accounting for 10% of the country's GDP and more than 80% of its foreign exchange earnings. The workforce in this sector is predominantly made up of women, with 2.5 million women working in the industry. However, these women face numerous challenges in carrying out their culturally-expected household responsibilities, including childcare, due to severe resource constraints. As a result, the children of these working women have a higher incidence of malnutrition, particularly stunted growth. This study aims to identify the factors that contribute to stunting in children under the age of five whose mothers work in the RMG sector in Bangladesh.

METHODS

The study collected data from 267 female RMG workers in the Gazipur district of Bangladesh using a simple random sampling technique. Chi-square tests were used to determine the associations between the factors influencing child stunting, and Multinomial Logit Models were used to estimate the prevalence of these factors.

RESULTS

The study found that the prevalence of moderate and severe stunting among the children of RMG workers living in the Gazipur RMG hub was 19% and 20%, respectively. The study identified several significant predictors of child stunting, including the mother's education level, nutritional knowledge, control over resources, receipt of antenatal care, household size, sanitation facilities, and childbirth weight. The study found that improving the mother's education level, increasing household size, and receiving antenatal care during pregnancy were important factors in reducing the likelihood of child stunting. For example, if a mother's education level increased from no education to primary or secondary level, the child would be 0.211 (0.071-0.627) and 0.384 (0.138-1.065) times more likely to have a normal weight and height, respectively, than to be moderately stunted.

CONCLUSION

The study highlights the challenges faced by working women in the RMG sector, who often receive minimal wages and have limited access to antenatal care services. To address these challenges, the study recommends policies that support antenatal care for working-class mothers, provide daycare facilities for their children, and implement a comprehensive social safety net program that targets child nutrition. Improving the socioeconomic status of mothers is also critical to reducing child malnutrition in this population.

Prevalence and Associated Risk Factors of Soil-Transmitted Helminth Infections among Schoolchildren around Lake Tana, Northwest Ethiopia

Background

Soil-transmitted helminths (STHs) are among the most common neglected tropical diseases widely distributed in tropical countries with poor socioeconomic development. Ascaris lumbricoides, Trichuris trichiura, and hookworm are the three major STHs. This study aimed to determine the prevalence of STHs and associated risk factors among schoolchildren in selected primary schools around Lake Tana, Northwestern Ethiopia.

Methods

A school-based cross-sectional study was conducted from February to May 2021 involving 337 study participants. A systematic random sampling method was utilized to select the study participants from the selected schools. Data related to sociodemographic characteristics of the study participants and risk factors for STH infections were collected using a pretested questionnaire. Stool samples were collected in sterile plastic containers from each participant and processed using Kato-Katz thick fecal smear and Ritchie's concentration techniques. The data were analyzed using the Statistical Package for Social Sciences software tool version 23, and factors with a p < 0.05 were considered as statistically significant.

Results

The overall prevalence of STH infection was 38.3% (95% CI: 33.1-43.7). Hookworm infection was the predominant STH infection, which was detected in 26.1% schoolchildren followed by A. lumbricoides (14.8%) and T. trichiura (1.5%). Most of the study subjects (34.1%) had single infections, whereas only 4.2% study subjects had multiple helminthic infections. Among the risk factors considered in the study, lack of shoe wearing habit (adjusted odds ratio [AOR]=29.5; 95% confidence interval [CI]=6.59-132.55; p < 0.001), lack of knowledge on the prevention and control methods (AOR = 5.41; 95% CI = 2.44-11.98; p < 0.001), engagement in irrigation activities (AOR = 2.14; 95% CI = 1.02-4.57, p = 0.049), lack of toilet (AOR = 3.06; 95% CI = 1.31-7.16; p = 0.01), children grades of 5-8 (AOR = 2.62; 95% CI = 1.26-5.43; p = 0.01), playing on soils (AOR = 5.90; 95% CI = 2.79-12.49; p < 0.001), lack of fingernail trimming habit (AOR = 3.21; 95% CI = 1.57-6.55; p = 0.001), and male gender (AOR = 2.28; 95% CI: 1.19-4.39; p = 0.013) were significant explanatory factors for STH infection among schoolchildren in the study area.

Conclusions

The present study showed that STHs were common among schoolchildren around Lake Tana. Therefore, education on personal and environmental hygiene should be taken into account to reduce the prevalence of STH infection in the study area.

Intestinal Parasitic Infection Among Rural Schoolchildren in Taiz, Yemen: School-based Assessment of The Prevalence and Associated Risk Factors

Yemen is an underdeveloped country plagued by poverty, disease, and social conflicts. Furthermore, most of the population lives in rural areas and is vulnerable to intestinal parasite infections (IPI). School-based cross-sectional studies were conducted between 1 February and 31 March 2019 among schoolchildren in rural communities in the Sabir Almawadim and Almawasit districts of Taiz, southwest Yemen. A structured questionnaire collected information regarding sociodemographic characteristics and risk factors. Wet mount and formol-ether concentration techniques were used to detect and identify intestinal parasites in stool specimens. The stool specimens were collected from each study participant using a clean, leak-proof, and adequately labeled stool cup. Statistical analysis of the data was performed using SPSS version 20. Of the 478 students screened for intestinal parasites, 245 (51.26 %) had at least one parasite. The prevalence of protozoa was higher than helminths (30.3 % versus 20.9 %, respectively). The percentages of single, double, and triple infections were 37.4 %, 4.4 %, and 1.7 %, respectively. Giardia lamblia was the most prevalent pathogen (15.5 %), followed by E. hisrolyrica/dispar (14.9 %), Schistosoma mansoni (13.3 %), Ascaris lumbricoides (3.8 %), Trichuris trichiura (2.9 %), and Enterobius vermicularis (1.3 %). Multivariate analysis confirmed that practicing unwashed hands before eating, open field defecation, unwashed fruits and vegetables, and dirty unclipped fingernails were the most significant predictors of high risk of IPIs (p <0.05). Regarding Schistosoma mansoni, multivariate analysis identified the behaviors of practicing swimming in the river/ponds and practicing open defecation, especially near water sources, as independent risk factors for Schistosoma mansoni infection among schoolchildren. The current study showed that rural areas in Taiz were significantly infected with IPIs, showing that IPIs remains a significant public health problem in low-income communities. Consequently, prevention efforts should focus on treating and deworming schoolchildren regularly, promoting health education in rural schools, conducting personal hygiene inspections for students, and ensuring that schools have sanitary facilities.

Using Routinely Collected Health Records to Identify the Fine-Resolution Spatial Patterns of Soil-Transmitted Helminth Infections in Rwanda

Background. Soil-transmitted helminths (STH) are parasitic diseases with significant public health impact. Analysis is generally based on cross-sectional prevalence surveys; outcomes are mostly aggregated to larger spatial units. However, recent research demonstrates that infection levels and spatial patterns differ between STH species and tend to be localized. Methods. Incidence data of STHs including roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura) and hookworms per primary health facility for 2008 were linked to spatially delineated primary health center service areas. Prevalence data per district for individual and combined STH infections from the 2008 nationwide survey in Rwanda were also obtained. Results. A comparison of reported prevalence and incidence data indicated significant positive correlations for roundworm (R2 = 0.63) and hookworm (R2 = 0.27). Weak positive correlations were observed for whipworm (R2 = 0.02) and the three STHs combined (R2 = 0.10). Incidence of roundworm and whipworm were found to be focalized with significant spatial autocorrelation (Moran’s I > 0: 0.05−0.38 and p ≤ 0.03), with (very) high incidence rates in some focal areas. In contrast, hookworm incidence is ubiquitous and randomly distributed (Moran’s I > 0: 0.006 and p = 0.74) with very low incidence rates. Furthermore, an exploratory regression analysis identified relationships between helminth infection cases and potential environmental and socio-economic risk factors. Conclusions. Findings show that the spatial distribution of STH incidence is significantly associated with soil properties (sand proportion and pH), rainfall, wetlands and their uses, population density and proportion of rural residents. Identified spatial patterns are important for guiding STH prevention and control programs.

Neurocysticercosis control for primary epilepsy prevention: a systematic review

Neurocysticercosis (NCC) is a leading cause of preventable epilepsy in lower- and upper- middle-income countries (LMICs/UMICs). NCC is a human-to-human transmitted disease caused by ingestion of Taenia solium eggs from a Taenia carrier. T. solium infection control is the key to reduce NCC incidence. This systematic review aims to identify T. solium control programs that can provide frameworks for endemic areas to prevent NCC-related epilepsy. A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Cochrane Library databases in March 2021. After title and abstract review, full texts were screened for qualitative analysis. Additional articles were identified via citation search. Of 1322 total results, 34 unique studies were included. Six major intervention types were identified: national policy (8.8%), community sanitation improvement (8.8%), health education (8.8%), mass drug administration (29.4%), pig vaccination and treatment (32.4%), and combined human and pig treatment (11.8%). Overall, 28 (82.4%) studies reported decreased cysticercosis prevalence following the intervention. Only health education and combined human and pig treatment were effective in all selected studies. NCC causes preventable epilepsy in LMICs/UMICs and its incidence can be reduced through T. solium control. Most interventions that disrupt the T. solium transmission cycle are effective. Long-term sustained results require comprehensive programs, ongoing surveillance, and collaborative effort among multisectoral agencies.

The impact of unconditional cash transfers on morbidity and health-seeking behaviour in Africa: evidence from Ghana, Malawi, Zambia and Zimbabwe

Unconditional cash transfers have demonstrated widespread, positive impacts on consumption, food security, productive activities and schooling. However, the evidence to date on cash transfers and health-seeking behaviours and morbidity is not only mixed, but the evidence base is biased towards conditional programmes from Latin America and is more limited in the context of Africa. Given contextual and programmatic design differences between the regions, more evidence from Africa is warranted. We investigate the impact of unconditional cash transfers on morbidity and health-seeking behaviour using data from experimental and quasi-experimental study designs of five government cash transfer programs in Ghana, Malawi, Zambia and Zimbabwe. Programme impacts were estimated using difference-in-differences models with longitudinal data. The results indicate positive programme impacts on health seeking when ill and on health expenditures. Our findings suggest that while unconditional cash transfers can improve health seeking when ill, morbidity impacts were mixed. More research is needed on longer-term impacts, mechanisms of impact and moderating factors. Additionally, taken together with existing evidence, our findings suggest that when summarizing the impacts of cash transfers on health, findings from conditional and unconditional programmes should be disaggregated.

The first report on the prevalence of soil-transmitted helminth infections and associated risk factors among traditional pig farmers in Bali Province, Indonesia

Background and Aim:

Pigs are the main livestock commodity in Bali Province, Indonesia, where traditional farming practices are widely used. Traditional pig farmers are often closely associated with poverty and a perceived lack of knowledge regarding health and hygiene. Data on soil-transmitted helminthiasis (STH) and risk factors associated with STH worm infection among traditional pig farmers in Bali were previously unavailable. This study aimed to analyze the prevalence and risk factors for STH infections among traditional pig farmers in Bali Province, Indonesia.

Materials and Methods:

This study involved the fecal examination of 238 traditional pig farmers from all areas of Bali Province in Indonesia. In addition, several pig feces samples were combined into one pooled sample belonging to each farm. All fresh fecal samples were stored in a 5% formaldehyde solution before being analyzed using concentration flotation techniques. Subsequently, risk factors were determined through an interview and a questionnaire. The odds ratio (OR) and Chi-square tests were used to determine the risk factors associated with STH infections.

Results:

The result showed that there was a high prevalence of STH infections among traditional pig farmers and pig farms in Bali, with rates of 21.8% and 76.5%, respectively. This could be due to risk factors, such as personal hygiene (OR: 5.756; confidence interval [CI]: 2.96-11.193; p=0.00), sanitation (OR: 1.914; CI: 1.024-3.576; p=0.042), education level (OR: 7.579; CI: 2.621-21.915; p=0.00), household income (OR: 2.447; CI: 1.122-5.338; p=0.025), and occupation (OR: 2.95; CI: 1.356-6.415; p=0.006).

Conclusion:

The infections seen in farmers were distributed among hookworm, Ascaris spp., and Trichuris spp., at 15.1%, 9.2%, and 4.2%, respectively. The risk factors associated with infections of STH and Ascaris spp. were personal hygiene, home sanitation, education level, household income, and having a primary occupation as a traditional pig farmer. In contrast, personal hygiene, education level, and primary occupation were the only risk factors for hookworm infection, while personal hygiene and home sanitation were the risk factors associated with Trichuris spp. infection. The limitation of this study was that the number of samples was relatively small due to the difficulty of obtaining stool samples from traditional pig farmers, with many individuals refusing to provide their stool for inspection. We suggest that future research focus on identifying the species of worms that infect traditional pig farmers and to better identify the zoonotic link of STH transmission from pigs to humans.

Prevalence of S. mansoni Infection and Associated Risk Factors among School Children in Guangua District, Northwest Ethiopia

Methods

A cross-sectional study design was employed. Four hundred twenty-two participants were selected. Data was collected through observation and interview with structured questionnaire. Stool specimens were collected and examined using two-slide Kato-Katz method. The data were analyzed using SPSS version 23. Logistic regression was fitted for analysis. Variables with p value <0.25 in the univariate logistic regression analysis were entered into the multivariable logistic regression model. Those with <0.05 were identified as significantly associated risk factors. To assure the quality of the data, training was given for data collectors and supervisors, and the tools were pretested on 5% of the sample size.

Results

404 (95.7%) school children were enrolled in the study. The overall prevalence of S. mansoni was 12.6%. School children in the age group 5-9 years old (AOR (95% CI): 22.27 (3.70-134.01), p = 0.001), age group 10-14 years old (AOR (95% CI): 4.58 (1.14-18.42), p = 0.032), grade levels 5-8 (AOR (95% CL): 14.95 (4.297-52.03), p = 0.001),who swim frequently (AOR (95% CI): 11.35 (2.33-55.33), p = 0.003), and those who cultivate near the irrigation area (AOR (95% CI): 7.10 (2.31-21.80), p = 0.001) were significantly associated with high risk of S. mansoni infection. Conclusion and Recommendation. From the finding of the current study, it can be concluded that the prevalence of Schistosoma mansoni in the study area is relatively high. Age of fourteen and younger years old, swimming in the river, and irrigation practice were the main risk factors of S. mansoni infection. Thus, therapeutic interventions as well as health education are desirable.

Sensitivity Analysis of a Transmission Interruption Model for the Soil-Transmitted Helminth Infections in Kenya

As the world rallies toward the endgame of soil-transmitted helminths (STH) elimination by the year 2030, there is a need for efficient and robust mathematical models that would enable STH programme managers to target the scarce resources and interventions, increase treatment coverage among specific sub-groups of the population, and develop reliable surveillance systems that meet sensitivity and specificity requirements for the endgame of STH elimination. However, the considerable complexities often associated with STH-transmission models underpin the need for specifying a large number of parameters and inputs, which are often available with considerable degree of uncertainty. Additionally, the model may behave counter-intuitive especially when there are non-linearities in multiple input-output relationships. In this study, we performed a global sensitivity analysis (GSA), based on a variance decomposition method: extended Fourier Amplitude Sensitivity Test (eFAST), to a recently developed STH-transmission model in Kenya (an STH endemic country) to; (1) robustly compute sensitivity index (SI) for each parameter, (2) rank the parameters in order of their importance (from most to least influential), and (3) quantify the influence of each parameter, singly and cumulatively, on the model output. The sensitivity analysis (SA) results demonstrated that the model outcome (STH worm burden elimination in the human host) was significantly sensitive to some key parameter groupings: combined effect of improved water source and sanitation (ϕ), rounds of treatment offered (τ), efficacy of the drug used during treatment (h), proportion of the adult population treated (g_a: akin to community-wide treatment), mortality rate of the mature worms in the human host (μ), and the strength of the -dependence of worm egg production (γ). For STH control programmes to effectively reach the endgame (STH elimination in the entire community), these key parameter groupings need to be targeted since together they contribute to a strategic public health intervention.

Evaluation of School-Based Health Education Intervention on the Incidence of Soil-Transmitted Helminths in Pupils of Rural Communities of Eastern Kogi State, North Central Nigeria

The negative impact of soil-transmitted helminths (STHs) in Nigeria is enormous, and it poses serious public health issues and concerns. This study was undertaken to investigate the impact of health education intervention on reinfection of STHs in pupils of rural schools of Kogi East, North Central Nigeria. A total of 10 schools with the highest prevalence of STHs at baseline were selected from the 45 schools assessed during the baseline survey. These 10 schools were randomly paired into two groups of 5 schools per group. Five schools were dewormed and given health education (DHE) intervention while the other 5 schools were dewormed only (DO) without health education. Reassessment of schools for reinfection was carried out for a period of 12 months. Data obtained were analyzed using descriptive statistics. Student's t-test was used to make comparison between interventions in the incidence of infections. Analysis was carried out at p < 0.05. Reinfection with STHs was observed from the 28th week (7th month) of both interventions with incidence of 0.29 (2 pupils) and 1.00 (7 pupils) in DO and DHE schools, respectively. In the 36th week (9th month), incidence observed in schools given DHE was 0.56 (5 pupils) while incidence of 0.89 (8 pupils) was observed in DO schools, and there was no significant difference (t = -1.000, p = 0.347) between the interventions. At 48th week (12th month), there was no significant difference (t = -0.547, p = 0.599) in incidence between the DHE and DO schools with incidence of 1.00 (12 pupils) and 0.83 (10 pupils), respectively. Hookworms had an incidence of 0.78 (7 pupils) at DHE schools and 0.56 (5 pupils) at DO schools in the 36th week while an incidence of 0.92 (11 pupils) and 0.83 (10 pupils) at DHE and DO schools, respectively, in the 48th week. Ascaris lumbricoides was only observed in DHE schools in a pupil with an incidence of 0.11 (1 pupil) and 0.08 (1 pupil) at 36th and 48th weeks. There was no significant difference in the prevalence of the parasites between DO and DHE intervention groups (p > 0.05). School-based health education intervention had no significant impact on STH incidence in pupils of rural schools in Kogi East. Community-based deworming should be encouraged alongside improvement in the water, sanitation, and hygiene infrastructures and practices at both school and home.

Prevalence of Soil-Transmitted Helminthes and Associated Risk Factors Among People of Ethiopia: A Systematic Review and Meta-Analysis

Background:

A Soil-transmitted helminthic infection (STHIs) remains a notable health problem in resource-limited countries.

Objective:

This systematic review and meta-analysis aimed to determine the overall prevalence of STH infections in Ethiopia.

Methods:

Articles written in English were searched from online public databases. Searching terms taken separately and jointly were “prevalence,” “soil-transmitted helminths” “nematode,” “Geo-helminths,” “roundworm,” “Necator,” “Ancylostoma,” “Ascaris,” “Trichuris,” “hookworm,” “whipworm,” “ S. strecoralies,” “associated factors,” and “Ethiopia.” We used STATA version 14 for meta-analysis and Cochran’s Q test statistics and the I2 test for heterogeneity.

Result:

From 297 reviewed articles 41 fulfilled the inclusion criteria. The pooled prevalence of STH infections in Ethiopia was 36.78% Ascaris lumbricoides had the highest pooled prevalence 17.63%, followed by hook worm12.35%. Trichuris trichiura 7.24% when the prevalence of S. strecoralies was 2.16% (95% CI: 0.97-3.35). Age, sex, residence, family education level, lack of shoe wearing habits and open defecation were identified as risk factors for STH infection. Eating unwashed and uncooked fruit and vegetables increased the risk of STH infection by 1.88 times while untrimmed finger nail and lack of hand washing habits increase the risk of STH infection by 1.28 and 3.16 times respectively with 95% CI.

Limitation:

Lack of published studies from Afar, Gambela, Somali, and Benshangul gumuz regions may affect the true picture. The other limitation is that the search strategy will be restricted articles published only in the English language but there might be articles that published using another language.

Conclusion:

Ascaris lumbricoides, hookworms and Trichuris trichiura, are the most prevalent soil-transmitted helminthes infections in Ethiopia. Age, sex, residence, family education level, lack of shoe wearing habits Open defecation untrimmed finger nail and lack of hand washing habits significantly associated with STH infection. When eating unwashed, uncooked fruit and vegetables were not significantly associated with STH infection. Strategic use of anti-helminthic, health education, and adequate sanitation, taking into account this epidemiologic information is helpful in the control of STH infections in Ethiopia.

Cutaneous larva migrans in early infancy: A Ugandan case report

Helminths are an important cause of worm infestation in low-income countries. The majority spread with soil to skin contact. In unusual patients presenting below 1 year, treatment can be challenging. The disease can be self-limiting; however, treatment is believed to reduce progression to more serious disease. Here, we present a case of a 3-month-old with cutaneous larva migrans.

Modelling the ability of mass drug administration to interrupt soil-transmitted helminth transmission: Community-based deworming in Kenya as a case study

The World Health Organization has recommended the application of mass drug administration (MDA) in treating high prevalence neglected tropical diseases such as soil-transmitted helminths (STHs), schistosomiasis, lymphatic filariasis, onchocerciasis and trachoma. MDA—which is safe, effective and inexpensive—has been widely applied to eliminate or interrupt the transmission of STHs in particular and has been offered to people in endemic regions without requiring individual diagnosis. We propose two mathematical models to investigate the impact of MDA on the mean number of worms in both treated and untreated human subpopulations. By varying the efficay of drugs, initial conditions of the models, coverage and frequency of MDA (both annual and biannual), we examine the dynamic behaviour of both models and the possibility of interruption of transmission. Both models predict that the interruption of transmission is possible if the drug efficacy is sufficiently high, but STH infection remains endemic if the drug efficacy is sufficiently low. In between these two critical values, the two models produce different predictions. By applying an additional round of biannual and annual MDA, we find that interruption of transmission is likely to happen in both cases with lower drug efficacy. In order to interrupt the transmission of STH or eliminate the infection efficiently and effectively, it is crucial to identify the appropriate efficacy of drug, coverage, frequency, timing and number of rounds of MDA.

We determine the best options for annual and biannual mass drug administration to control soil-transmitted helminths. An additional round of drugs can allow weaker drugs to be used. We apply the results to a community-based deworming project in Kenya.

High-Prevalence Stunting in Preschool Children (1-5 Years) Attending Selected Health Centers in a Food Rich Area-Bushenyi District Southwestern Uganda

The prevalence of stunting among children in Uganda and Sub-Saharan Africa is still high, and if Uganda is to achieve the food-related Sustainable Development Goals (SDGs), it must urgently invest in improving nutrition and sanitation. In a food rich area like Bushenyi, chronic undernutrition could be due to several other factors than mere scarcity of food. The Objective(s). This study was carried out to determine the prevalence and socioclinical factors responsible for chronic undernutrition (stunting) among preschool children aged 1-5 years in selected Health facilities in Bushenyi district. Methodology. This was a cross-sectional study assessing the prevalence of stunting and its associated factors among children aged 1-5 years attending selected health centers in Bushenyi District. Data was collected using a pretested questionnaire, taking anthropometric measurements (height/length), and stool analysis for eggs of soil-transmitted helminthes. Prevalence of stunting was presented as percentages. Logistic regression with adjusted prevalence ratio was performed to test the association between the sociodemographic and clinical factors and stunting at bivariate levels of analysis. Results. Most of the children were female, with a median age of 2.1 years and resided in semiurban areas of Bushenyi with their parents. Prevalence of stunting was 89.3%. Only 10.7% of the children were infested with soil-transmitted helminthes. Children likely to be stunted were those who drank unboiled water and were exclusively breastfed. Conclusion. There is a high prevalence of chronic malnutrition in Bushenyi district associated with parents'/care takers' low level of knowledge.

Model-Based Geostatistical Methods Enable Efficient Design and Analysis of Prevalence Surveys for Soil-Transmitted Helminth Infection and Other Neglected Tropical Diseases

Maps of the geographical variation in prevalence play an important role in large-scale programs for the control of neglected tropical diseases. Precontrol mapping is needed to establish the appropriate control intervention in each area of the country in question. Mapping is also needed postintervention to measure the success of control efforts. In the absence of comprehensive disease registries, mapping efforts can be informed by 2 kinds of data: empirical estimates of local prevalence obtained by testing individuals from a sample of communities within the geographical region of interest, and digital images of environmental factors that are predictive of local prevalence. In this article, we focus on the design and analysis of impact surveys, that is, prevalence surveys that are conducted postintervention with the aim of informing decisions on what further intervention, if any, is needed to achieve elimination of the disease as a public health problem. We show that geospatial statistical methods enable prevalence surveys to be designed and analyzed as efficiently as possible so as to make best use of hard-won field data. We use 3 case studies based on data from soil-transmitted helminth impact surveys in Kenya, Sierra Leone, and Zimbabwe to compare the predictive performance of model-based geostatistics with methods described in current World Health Organization (WHO) guidelines. In all 3 cases, we find that model-based geostatistics substantially outperforms the current WHO guidelines, delivering improved precision for reduced field-sampling effort. We argue from experience that similar improvements will hold for prevalence mapping of other neglected tropical diseases.

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.

A study on intestinal parasitic infections among school children in Karaikal

Introduction

Intestinal parasitic infections (IPIs) play a major role in global disease burden with significant morbidity. The most vulnerable age group was school going children and is transmitted through soil. About 90% of infected individuals remain asymptomatic. The present study was designed to screen for IPI among school children in Karaikal, to identify the asymptomatic infections and to assess the type and occurrence of IPIs.

Methodology

A cross-sectional study was carried out from July to September 2018 among school children in the age group of 6-14 years after getting ethical clearance. A total of 335 single stool samples were collected. The samples were subjected to macroscopic examination, microscopic examination and subjected to concentration techniques such as salt floatation and formal ether sedimentation technique. Two separate fresh stool smears were made on the microscopic slides for trichrome and modified acid-fast staining. The results were calculated as percentage, frequency/proportion, and Chi-square test using IBM SPSS software version 19.

Results

Only 90 (28%) out of 324 stool samples were positive for the presence of intestinal parasites. The sensitivity of formal ether sedimentation technique (58%) was higher than other techniques. None of the ova of helminths detected. Modified acid-fast staining was negative for coccidian parasites.

Conclusions

The low prevalence of protozoan parasites and total absence of helminths in the study revealed the effective role of nationwide deworming program and Swachh Bharat Abhiyan program. However, anthelminthic does not cover the protozoan parasites and it exists among asymptomatic healthy population.

Evaluation of vegetables grown in dry mountainous regions for soil transmitted helminths contamination

Infection caused by geo-helminth parasites are called geohelminthiasis are one of the global health problems. Vegetables eaten raw is the principal source of transmission of geo-helminth parasites. Pakistani people believe that eating raw vegetables are a significant source to get important vitamins and minerals. Based on the high incidence of pathogenic parasites and cultivating different vegetable types in the study areas, we conducted this study to evaluate the geo-helminth contamination of raw vegetables in northwest Khyber Pakhtunkhwa, Pakistan. This is a descriptive study comprised, 1942 samples of 25 various types of vegetables. The samples were examined in physiological saline solution using sedimentation and centrifugation methods. The findings were analyzed by Graph-Pad version 5. P value less than 0.05 (95% CI) was considered significant. Results showed that 16.5% (n=322) of all vegetables were contaminated with one or more type of geo-helminth parasites. Garlic was the highest (35%) and cauliflower the lowest (4%) contaminated samples respectively. Ascaris lumbricoides was the most common geo-helminth found followed by hook worm species while Trichuris trichura was the least in all the vegetable samples. Leafy vegetables were highly contaminated 25.3% than vegetables with root parts 21.2% and fruity 9.09%. More than half of the contaminated vegetables were contaminated with single species of geo-helminth (P<0.05) while less than half with multiple types of geo-helminth contamination. Ninety two vegetables samples were contaminated with 2 species of parasites (P<0.05) and 45 with 3 (P>0.05) species of geo-helminth parasites. Education level of vendors and means of display were not significantly associated while types of vegetable used were significantly associated with the prevalence of parasites. The findings of this study provide evidence that consumption of raw vegetable has a high risk of acquiring geo-helminth infections. The authors believe that preventing the human to enter to the vegetable farmland for defecation, avoiding the irrigation of agricultural fields via night soil, and educating the people on proper washing and cooking of vegetables may be useful in reducing parasitic infections.

Human Intestinal Parasitic Infections: Prevalence and Associated Risk Factors among Elementary School Children in Merawi Town, Northwest Ethiopia

Background

Intestinal parasitic infection is still common in Ethiopia. Periodic evaluation of the current status of human intestinal parasitic infections (HIPIs) is a prerequisite to controlling these health threats. This study is aimed at assessing the prevalence and determinant factors of HIPIs among elementary school-age children in Merawi town.

Methods

A school-based cross-sectional study design was used among 403 children. The direct wet mount method was used to diagnose the stool samples. The sociodemographic and behavioral characteristics of the respondents were collected using structured questionnaires. The data were analyzed using the chi-square test and logistic regression.

Results

Out of the 403 students, the overall prevalence of HIPIs was 173 (42.9%). The magnitudes of single and double infections were 39.7% and 3.2%, respectively. Seventy-two (17.9%) were positive for Entamoeba histolytica, 63 (15.4%) for Giardia lamblia, 28 (9.6%) for Ascaris lumbricoides, 22 (6.9%) for hookworm, and 1 (0.2%) for Schistosoma mansoni. The prevalence of intestinal parasites was high in the age group of 6–11 years compared to other age groups. The following were the risk factors associated with HIPIs: groups aging 6 to 11 (AOR = 9.581; 95% CI: 0.531-17.498; P = 0.008), aging 12 to 18 (AOR = 3.047; 95% CI: 0.055-1.828; P = 0.008), not washing of hands after defecation (AOR = 3.683; 95% CI; 1.577-8.598; P = 0.003), not regularly washing of hands after defecation (AOR = 2.417; 95% CI; 1.224-4.774; P = 0.003), dirty fingernails (AOR = 2.639; 95% CI: 1.388-5.020; P = 0.003), not wearing shoes (AOR = 2.779; 95% CI: 1.267-6.096; P = 0.011), rural residence (AOR = 6.6; 95% CI; 0.06-0.351; P < 0.0001), and a family size greater than or equal to five (AOR = 2.160; 95% CI: 1.179-3.956; P = 0.013).

Conclusion

The prevalence of HIPIs among elementary school children in Merawi town was very high. Thus, there is a need for intensive health education for behavioral changes related to personal hygiene and mass treatment for effective control of HIPIs in the study area.

Prevalence, Infection Intensity and Associated Factors of Soil-Transmitted Helminthiasis Among School-Aged Children from Selected Districts in Northwest Ethiopia

Background

Globally, soil-transmitted helminths affect beyond a billion people and cause 1.9 million disability-adjusted life years worldwide. It affects children disproportionately due to their unaware activities like walking barefoot, playing with dirty objects that might be contaminated with feces. The control of soil-transmitted helminths principally relies on periodic deworming using either a single dose of albendazole/mebendazole. To assure the effectiveness of this measure, performing continuous parasitological survey is necessary. Herein, the prevalence, intensity and associated factors of soil-transmitted helminth infections were assessed among school-aged children in northwest Ethiopia.

Methods

A cross-sectional study design was conducted among school-aged children (6–14 years old) from January 21st to February 21st/2019. Multistage sampling technique was employed. A Kato-Katz concentration technique was utilized to detect STHs in stool samples. Moreover, risk factors for STH infections were assessed using well-structured questionnaire. Bivariate and multivariate analyses were used to assess the association between explanatory and the outcome variables. The magnitude of the association was measured using the adjusted odds ratio (AOR) and 95% confidence interval (CI). A P-value <0.05 was considered statistically significant.

Results

The overall STHs prevalence in this study was 32.3% (95% CI: 29–35.6%) with Ascaris lumbricoides being the predominant species (24.3%) followed by hookworm (8.9%) and Trichuris trichiura (1%). Most (80.3%) of the infected school-aged children had light-intensity infections. Age of 11 years and above (AOR, 12.9, 95% CI, 1.6–103.6, P=0.004), being residing in Chuahit district (AOR, 3.9, 95% CI, 2.3–6.5, P<0.001), and untreated water supply (AOR, 1.7, 95% CI, 1.1–2.7, P=0.018) were identified as predictors for the overall STH prevalence.

Conclusion

Our findings revealed STH infections are considerable health problems in the study areas. Thus, public health interventions such as provision of safe water supply, health education, and de-worming programs should be regularly implemented in the study areas.

In vitro anthelmintic activity of Chenopodium album and in-silico prediction of mechanistic role on Eisenia foetida

Helminths born diseases are related to pitiable management practices and improper control strategies. The medicinal plants contain various phytoconstituents that are liable for their anthelmintic activity. The aerial parts of the Chenopodium album were successively extracted with microwaves assisted extraction using petroleum ether, ethyl acetate, methanol, hydroalcoholic and aqueous solvents to get respective extracts (CAPE, CAEE, CAME, CAHE, and CAAE). All the extracts were analyzed for preliminary phytochemical screening for the identification of phytoconstituents. The anthelmintic activity was analyzed on Indian adult earthworms Eisenia foetida using piperazine citrate (PCT) as a standard drug. All the extracts (apart from CAAE) lead to paralysis and fatality of the earthworms. CAEE extract exhibits highly significant anthelmintic activity at a 10 mg/ml concentration by causing paralysis and fatality of earthworms and was more potent than PCT suspension. At a concentration of 10 mg/ml, paralysis and death time for CAEE was recorded as (10.08 ± 1.11) and (65.28 ± 2.09) respectively, while for standard piperazine citrate, it was recorded as (22.96 ± 1.12) and (65.09 ± 1.23). The CAEE exhibits two major compounds by LC-MS, i.e., NG and DG, that are mainly accountable for the Chenopodium album anthelmintic activity. The plant possesses GABA-mimetic action and thereby leads to flaccid, reversible paralysis of the body wall muscle.

Diagnosis of soil-transmitted helminths using the Kato-Katz technique: What is the influence of stirring, storage time and storage temperature on stool sample egg counts?

Background

Soil-transmitted helminths infect about one fifth of the world’s population and have a negative impact on health. The Kato-Katz technique is the recommended method to detect soil-transmitted helminth eggs in stool samples, particularly in programmatic settings. However, some questions in its procedure remain. Our study aimed to investigate the effect of storage time, storage temperature and stirring of stool samples on fecal egg counts (FECs).

Methodology/Principal findings

In the framework of a clinical trial on Pemba Island, United Republic of Tanzania, 488 stool samples were collected from schoolchildren. These samples were evaluated in three experiments. In the first experiment (n = 92), two Kato-Katz slides were prepared from the same stool sample, one was stored at room temperature, the other in a refrigerator for 50 hours, and each slide was analyzed at nine time points (20, 50, 80, 110, 140 minutes, 18, 26, 42 and 50 hours). In the second experiment (n = 340), whole stool samples were split into two, one part was stored at room temperature, and the other part was put in a refrigerator for 48 hours. From each part one Kato-Katz slide was prepared and analyzed at three time points over two days (0, 24 and 48 hours). In the third experiment (n = 56), whole stool samples where stirred for 15 seconds six times and at each time point a Kato-Katz slide was prepared and analyzed.

Mean hookworm FECs of Kato-Katz slides stored at room temperature steadily decreased following slide preparation. After two hours, mean hookworm FECs decreased from 22 to 16, whereas no reduction was observed if Kato-Katz slides were stored in the refrigerator (19 vs 21). The time x storage interaction effect was statistically significant (coefficient 0.26, 95% CI: 0.17 to 0.35, p < 0.0001). After 24 hours mean hookworm FECs dropped close to zero, irrespective of the storage condition. Whole stool samples stored at room temperature for one day resulted in a mean hookworm FEC decrease of 23% (p < 0.0001), compared to a 13% reduction (p < 0.0001) if samples were stored in the refrigerator. Fecal egg counts of A. lumbricoides and T. trichiura remained stable over time regardless of storage temperature of whole stool samples. Finally, we found a significant reduction of the variation of hookworm and T. trichiura eggs with increasing rounds of stirring the sample, but not for A. lumbricoides. For hookworm we observed a simultaneous decrease in mean FECs, making it difficult to draw recommendations on stirring samples.

Conclusions/Significance

Our findings suggest that stool samples (i) should be analyzed on the day of collection and (ii) should be analyzed between 20–30 minutes after slide preparation; if that is not possible, Kato-Katz slides can be stored in a refrigerator for a maximum of 110 minutes.

Intestinal worms, such as hookworm, Ascaris lumbricoides, and Trichuris trichiura, infect one in five people worldwide. In children, they can cause cognitive and physical impairment. Accurate detection of these infections is important to treat patients and control the spread of intestinal worms. Currently, the Kato-Katz technique is the most commonly used diagnostic method, particularly, in programmatic settings. However, there are still several open questions to be resolved. In this study, we aimed at exploring the effect of storage time, storage temperature, and stirring of stool samples on the number of worm eggs detectable by the Kato-Katz technique. We included 488 stool samples collected from schoolchildren on Pemba Island, United Republic of Tanzania. We found that, at room temperature, hookworm eggs rapidly disappear from Kato-Katz slides, but storing them in a refrigerator preserves eggs for up to 110 minutes. For A. lumbricoides and T. trichiura no relevant trend in fecal egg counts in Kato-Katz slides over time and or influence of storing temperature was detected. However, storing whole stool samples in a refrigerator overnight did not prevent hookworm eggs from disappearing, thus, we recommend analyzing all samples on the day of collection. For A. lumbricoides and T. trichiura fecal egg counts remained stable in whole stool samples over time, regardless of storage temperature. Finally, we found that stirring samples reduced the variation of fecal egg counts for hookworm and T. trichiura, but not for A. lumbricoides. Hookworm fecal egg counts decreased with increasing rounds of sample stirring.

Efficacy and Safety of Ascending Dosages of Moxidectin and Moxidectin-albendazole Against Trichuris trichiura in Adolescents: A Randomized Controlled Trial

BACKGROUND

Preventive chemotherapy is the main strategy to control soil-transmitted helminth (STH) infections. Albendazole and mebendazole are ubiquitously used, but they are not sufficiently effective against Trichuris trichiura. Moxidectin might be a useful addition to the small drug armamentarium. However, the optimal dosage of moxidectin alone and in combination with albendazole against T. trichiura and other STHs has not yet been determined.

METHODS

A Phase II, randomized, placebo-controlled, dose-finding trial was conducted in 2 secondary schools on Pemba Island, Tanzania. Using a computer-generated list, T. trichiura-infected adolescents were randomly assigned to 7 treatment arms: 8, 16, or 24 mg of moxidectin monotherapy; 8, 16, or 24 mg of moxidectin plus 400 mg of albendazole combination therapy; or placebo. The primary outcome was cure rate (CR) against T. trichiura, analyzed 13 to 20 days after treatment by quadruple Kato-Katz thick smears.

RESULTS

A total of 290 adolescents were enrolled (41 or 42 per arm). CRs against T. trichiura were 43, 46, and 44% for 8, 16, and 24 mg of moxidectin alone, respectively; 60, 62, and 66% for the same moxidectin dosages plus 400 mg of albendazole, respectively; and 12% for placebo. The moxidectin-albendazole arms also revealed higher CRs and egg reduction rates against hookworm than the monotherapy arms. Moxidectin and its combination with albendazole were well tolerated.

CONCLUSIONS

Moxidectin-albendazole is superior to moxidectin. There is no benefit of using doses above 8 mg, which is the recommended dose for onchocerciasis. The moxidectin-albendazole combination of 8 mg plus 400 mg should be investigated further to develop recommendations for appropriate control of STH infections.

CLINICAL TRIALS REGISTRATION

NCT03501251.

A cross-sectional survey on parasitic infections in schoolchildren in a rural Tanzanian community

Infectious diseases remain the leading cause of death in children in low- and middle-income countries. Infection with helminths and intestinal protozoa cause considerable morbidity. The aim of this study was to assess the health status of schoolchildren in nine villages of the Kilombero district in Tanzania. We conducted a cross-sectional survey and subjected 427 children aged 6-12 years to standardized diagnostic tests. We found that 15% of children were infected with Entamoeba histolytica/Entamoeba dispar/Entamoeba moshkovskii, 12% with Schistosoma mansoni, and 5% with Plasmodium falciparum. The most common soil-transmitted helminth species was Trichuris trichiura (7%). Strongyloides stercoralis, Schistosoma haematobium, Giardia intestinalis and lymphatic filariasis were rare. Having a latrine inside the house was associated with a lower odds of parasite infections (odds ratio (OR) 0.51, 95% confidence interval (CI) 0.27-0.96, p = 0.04). Children from households with goats were at higher odds of E. histolytica/E. dispar/E. moshkovskii infection (OR 3.03, 95%%CI 1.29-7.10, p = 0.01).When compared to a cross-sectional survey conducted in the same district in the 1980s, there seems to have been a substantial reduction in the prevalence and intensity of parasitic infections, except for T. trichiura, which showed a similar prevalence. Our data suggest that the general development, coupled with infectious disease control programmes improved children's health markedly. However, continued efforts to control parasitic diseases, including new approaches of drug combinations, stronger intersectoral collaboration, rigorous surveillance and public health responses tailored to the local settings are needed to move from control to elimination.

The Control of Zoonotic Soil-Transmitted Helminthoses Using Saprophytic Fungi

Soil-transmitted helminths (STHs) are parasites transmitted through contact with soil contaminated with their infective eggs/larvae. People are infected by exposure to human-specific species or animal species (zoonotic agents). Fecal samples containing eggs of Ascaris suum or Lemurostrongylus sp. were sprayed with spores of the soil saprophytic filamentous fungi Clonostachys rosea (CR) and Trichoderma atrobrunneum (TA). The antagonistic effect was assessed by estimating the viability of eggs and their developmental rate. Compared to the controls (unexposed to fungi), the viability of the eggs of A. suum was halved in CR and decreased by two thirds in TA, while the viability of the eggs of Lemurostrongylus sp. was reduced by one quarter and one third in CR and TA treatments, respectively. The Soil Contamination Index (SCI), defined as the viable eggs that attained the infective stage, reached the highest percentages for A. suum in the controls after four weeks (66%), with 21% in CL and 11% in TA. For Lemurostrongylus sp., the values were 80%, 49%, and 41% for control, CR and TA treatments, respectively. We concluded that spreading spores of C. rosea or T. atrobrunneum directly onto the feces of animal species represents a sustainable approach under a One Health context to potentially reduce the risk of zoonotic STHs in humans.

Helminth Egg Automatic Detector (HEAD): Improvements in development for digital identification and quantification of helminth eggs and their application online

Helminths are parasitic worms that constitute a major public health problem. Conventional analytical techniques to evaluate helminth eggs in environmental samples rely on different steps, namely sedimentation, filtration, centrifugation, and flotation, to separate the eggs from a variety of particles and concentrate them in a pellet for direct observation under an optical microscope. To improve this process, a new approach was implemented in which various image processing algorithms were developed and implemented by a Helminth Egg Automatic Detector (HEAD). This allowed identification and quantification of pathogenic helminth eggs of global medical importance and it was found to be useful for relatively clean wastewater samples. After the initial version, two improvements were developed: first, a texture verification process that reduced the number of false positive results; and second, the establishment of the optimal thresholds (morphology and texture) for each helminth egg species. This second implementation, which was found to improve on the results of the former, was developed with the objective of using free software as a platform for the system. This does not require the purchase of a license, unlike the previous version that required a Mathworks® license to run. After an internal statistical verification of the system was carried out, trials in internationally recognized microbiology laboratories were performed with the aim of reinforcing software training and developing a web-based system able to receive images and perform the analysis throughout a web service. Once completed, these improvements represented a useful and cheap tool that could be used by environmental monitoring facilities and laboratories throughout the world; this tool is capable of identifying and quantifying different species of helminth eggs in otherwise difficult environmental samples: wastewater, soil, biosolids, excreta, and sludge, with a sensitivity and specificity for the TensorFlow (TF) model in the web service values of 96.82% and 97.96% respectively. Additionally, in the case of Ascaris, it may even differentiate between fertile and non-fertile eggs.

The impact of Worms and Ladders, an innovative health educational board game on Soil-Transmitted Helminthiasis control in Abeokuta, Southwest Nigeria

In most endemic sub-Saharan African countries, repeated infections with soil-transmitted helminth (STH) occur as early as six weeks after the end of mass drug administration (MDA) with albendazole. In this study, we designed a new health educational board game Worms and Ladders and evaluated its potential to complement MDA with albendazole and reduce reinfection rates through the promotion of good hygiene practices among school-aged children. The evaluation employed a randomized control trial (RCT) design. Baseline knowledge, attitude and practices (KAP) relating to STH were obtained using a questionnaire from 372 pupils across six schools in Abeokuta, Nigeria. Schools were randomly assigned into intervention and control group, with the former and latter receiving Worms and Ladders and the common Snake and Ladder board game respectively. Fresh stool samples were also collected at baseline for STH diagnosis before administering 400mg single dose albendazole. Follow-up assessments of STH burden and KAP were conducted three and six months' post-intervention. Data generated from the study were analyzed using SPSS 20.0 software, with confidence interval set at 95%. Prevalence of STH dropped from 25.0% to 10.4% in the intervention group and 49.4% to 33.3% in the control group at three months' post-intervention. The prevalence further dropped to 5.6% in the intervention group at six months’ post-intervention. However, it increased to 37.2% in the control group at six months' post-intervention. There was a significant difference (p<0.05) in prevalence after intervention among the groups. KAP on transmission, control and prevention of STH significantly improved (p<0.05) from 5.2% to 97.9% in the intervention group compared to 6.2% to 7.1% in the control group. The Worms and Ladders board game shows the potential to teach and promote good hygiene behavior among SAC. These findings posit the newly developed game as a reliable tool to complement mass drug administration campaigns for STH control.

School-aged children are the most affected group of people in terms of burden due to soil-transmitted helminth infections. Unfortunately, the available treatment programme with albendazole cannot prevent reinfection. Health and hygiene education has been recommended to be effective at reducing the rate of STH infections through increased knowledge about transmission and improved hygiene attitude and practices. We, therefore, developed a health educational board game Worms and Ladders and evaluated its potential to complement treatment and reduce reinfection rates. Our findings show that the worm burden dropped significantly among children who played the newly developed game, compared to other children who played another game. The knowledge, attitude and practices of the children as regards STH also improved significantly. The Worms and Ladders board game, therefore, has the potential to promote good hygiene behavior, which in turn translated to a reduced rate of infections. These findings present the newly developed game as a reliable tool to complement mass drug administration campaigns for STH control.

Mathematical Model for Optimal Control of Soil-Transmitted Helminth Infection

In this paper, we study the dynamics of soil-transmitted helminth infection. We formulate and analyse a deterministic compartmental model using nonlinear differential equations. The basic reproduction number is obtained and both disease-free and endemic equilibrium points are shown to be asymptotically stable under given threshold conditions. The model may exhibit backward bifurcation for some parameter values, and the sensitivity indices of the basic reproduction number with respect to the parameters are determined. We extend the model to include control measures for eradication of the infection from the community. Pontryagian's maximum principle is used to formulate the optimal control problem using three control strategies, namely, health education through provision of educational materials, educational messages to improve the awareness of the susceptible population, and treatment by mass drug administration that target the entire population(preschool- and school-aged children) and sanitation through provision of clean water and personal hygiene. Numerical simulations were done using MATLAB and graphical results are displayed. The cost effectiveness of the control measures were done using incremental cost-effective ratio, and results reveal that the combination of health education and sanitation is the best strategy to combat the helminth infection. Therefore, in order to completely eradicate soil-transmitted helminths, we advise investment efforts on health education and sanitation controls.

Impact of Helminth Infections during Pregnancy on Vaccine Immunogenicity in Gabonese Infants

Helminth infections are common in sub-Saharan Africa. Besides direct clinical effects, a bias towards a T helper type 2 (Th2) cell immune response is observed. The consequences of parasite infection during pregnancy for the mother and particularly for the fetus and the newborn can be severe and may include impaired immune response during acute infection and vaccination. Here, we present data of immune responses to vaccines given within the expanded program on immunization (EPI) of infants born to helminth infected or non-infected mothers. The study was conducted in Lambaréné and surroundings, Gabon. Maternal helminth infection was diagnosed microscopically using the Kato-Katz method for soil-transmitted helminths (STH), urine filtration for Schistosoma haematobium infections and the saponin-based method for filarial infections. Plasma antibody levels to different vaccine antigens were measured in mothers and their offspring by enzyme-linked immunosorbent assay (ELISA) at different timepoints. We found 42.3% of the mothers to be infected with at least one helminth species. Significantly lower anti-tetanus toxoid immunoglobulin (Ig) G was detected in the cord blood of infants born to helminth infected mothers. Following vaccination, immune responses of the infants to EPI vaccines were similar between the two groups at nine and 12 months. Even though infection with helminths is still common in pregnant women in Gabon, in our setting, there was no evidence seen for a substantial effect on infants’ immune responses to vaccines given as part of the EPI.

Detection of Helminth Ova in Wastewater Using Recombinase Polymerase Amplification Coupled to Lateral Flow Strips

Ascaris lumbricoides is a major soil-transmitted helminth that is highly infective to humans. The ova of A. lumbricoides are able to survive wastewater treatment, thus making it an indicator organism for effective water treatment and sanitation. Hence, Ascaris ova must be removed from wastewater matrices for the safe use of recycled water. Current microscopic techniques for identification and enumeration of Ascaris ova are laborious and cumbersome. Polymerase chain reaction (PCR)-based techniques are sensitive and specific, however, major constraints lie in having to transport samples to a centralised laboratory, the requirement for sophisticated instrumentation and skilled personnel. To address this issue, a rapid, highly specific, sensitive, and affordable method for the detection of helminth ova was developed utilising recombinase polymerase amplification (RPA) coupled with lateral flow (LF) strips. In this study, Ascaris suum ova were used to demonstrate the potential use of the RPA-LF assay. The method was faster (< 30 min) with optimal temperature at 37 °C and greater sensitivity than PCR-based approaches with detection as low as 2 femtograms of DNA. Furthermore, ova from two different helminth genera were able to be detected as a multiplex assay using a single lateral flow strip, which could significantly reduce the time and the cost of helminth identification. The RPA-LF system represents an accurate, rapid, and cost-effective technology that could replace the existing detection methods, which are technically challenged and not ideal for on-site detection in wastewater treatment plants.

Preventive chemotherapy and anthelmintic resistance of soil-transmitted helminths - Can we learn nothing from veterinary medicine?

Current parasite control programs in veterinary species have moved away from mass anthelmintic treatment approaches due to the emergence of significant anthelmintic resistance (AR), and the availability of few classes of anthelmintics. A number of parallels between livestock and human helminths exist that warn of the risk of AR in human soil-transmitted helminthiases, yet current public health interventions continue to prioritize mass treatment strategies, a known risk factor for AR. This review discusses the existing parallels between human and animal helminth biology and management, along with current public health recommendations and strategies for helminth control in humans. The effectiveness of current recommendations and alternative management strategies are considered.

Current decline in schistosome and soil-transmitted helminth infections among school children at Loum, Littoral region, Cameroon

Introduction

Soil-transmitted helminth infections (STHs) and schistosomiasis have serious consequences for the health, education and nutrition of children in developing countries. As Loum is known as a highly endemic commune for these infections, several deworming campaigns have been carried out in the past. The purpose of this study was to determine any changes that have occurred since then in the characteristics of these infections among schoolchildren in this site.

Methods

A cross-sectional study was conducted in October 2016 on 289 schoolchildren. Stool and urine samples were collected and examined to determine the prevalence and intensity of helminth infections.

Results

The highest prevalence was noted for Schistosoma haematobium (34.2%), followed by Ascaris lumbricoides (8.6%), S. mansoni (4.9%) and Trichuris trichiura (4.9%) in decreasing order. A prevalence of less than 2% was noted for each of the other two helminths. The highest mean intensity was found for S. haematobium (39.6 eggs/10 ml of urine), followed by A. lumbricoides (24.2 eggs per gram of faeces: epg), Strongyloides stercoralis (16.6 epg) and Schistosoma mansoni (12.3 epg). The prevalence of T. trichiura was significantly higher in boys and that of S. haematobium in children aged 10 years or older, while the differences between other values of prevalence or between egg burdens were not significant.

Conclusion

Compared with values reported in 2003, the prevalence and intensity of schistosomiases and STH infections in Loum has sharply decreased in 2016. Confirmation of this decrease in the years to come allowed to space deworming campaigns among schoolchildren.

Intestinal parasites in six Islamic medieval period latrines from 10th-11th century Córdoba (Spain) and 12th-13th century Mértola (Portugal)

OBJECTIVE

To investigate the types of intestinal parasites that infected people living in Islamic period southern Iberia (al-Andalus), and compare with other regions of Europe.

MATERIALS

Four cesspits from 10^th-11^th century CE Córdoba (Spain), and two from 12^th-13^th century Mértola (Portugal).

METHODS

Sediment from each cesspit was analyzed using digital light microscopy and enzyme-linked immunosorbent assay (ELISA).

RESULTS

Analysis revealed eggs of roundworm (Ascaris lumbricoides) in every cesspit analyzed, but no evidence of other species of helminth or protozoal parasites.

CONCLUSION

Differences were noted between parasite species found in Mediterranean Europe and northern Europe, where a range of zoonotic parasites were endemic alongside sanitation-related parasites. We suggest that the scarcity of zoonotic parasites in southern Europe in the medieval period may reflect contrasts in climate between northern and southern Europe.

SIGNIFICANCE

The repeated identification of roundworm eggs suggests that al-Andalus was less hygienic than historically depicted. We did not note a difference between parasites found in Muslim and Christian regions of Iberia, and the predominance of parasites spread by fecal contamination of food is consistent with past research.

LIMITATIONS

The eggs of some species of parasite are fragile, so may theoretically have been present in the population but did not survive for us to identify them.

SUGGESTIONS FOR FURTHER RESEARCH

To further investigate the role of climate upon the parasites that affected past human populations.

A Review on the Current Knowledge and Prospects for the Development of Improved Detection Methods for Soil-Transmitted Helminth Ova for the Safe Reuse of Wastewater and Mitigation of Public Health Risks

Climate change, increase in population and scarcity of freshwater have led to a global demand for wastewater reuse in irrigation. However, wastewater has to be treated in order to minimize the presence of pathogens, in particular, the ova of soil-transmitted helminthes (STHs). Limiting the transmission via removal of STH ova, accurate assessment of risks and minimizing the exposure to the public have been recommended by health regulators. The World Health Organization (WHO) guideline specifies a limit of ≤1 ova/L for safe wastewater reuse. Additionally, the Australian Guidelines for Water recycling (AGWR) recommend a hydraulic retention time of over 25 days in a lagoon or stabilization pond to ensure a 4 log reduction value of helminth ova and to mitigate soil-transmitted helminths associated risks to humans. However, the lack of fast and sensitive methods for assessing the concentration of STH ova in wastewater poses a considerable challenge for an accurate risk assessment. Consequently, it has been difficult to control soil-transmitted helminthiasis despite effective mass drug administration. This limitation can be overcome with the advent of novel techniques for the detection of helminth ova. Therefore, this review presents an assessment of the current methods to detect the viable ova of soil-transmitted helminths in wastewater. Furthermore, the review focuses on the perspectives for the emerging state-of-the-art research and developments that have the potential to replace currently available conventional and polymerase chain reaction based methods and achieve the guidelines of the WHO in order to allow the safe reuse of wastewater for non-potable applications, thereby minimizing public health risks.

Development and validation of a multiplexed-tandem qPCR tool for diagnostics of human soil-transmitted helminth infections

Soil-transmitted helminths (STH) are a major cause of morbidity in tropical developing countries with a global infection prevalence of more than one billion people and disease burden of around 3.4 million disability adjusted life years. Infection prevalence directly correlates to inadequate sanitation, impoverished conditions and limited access to public health systems. Underestimation of infection prevalence using traditional microscopy-based diagnostic techniques is common, specifically in populations with access to benzimidazole mass treatment programs and a predominance of low intensity infections. In this study, we developed a multiplexed-tandem qPCR (MT-PCR) tool to identify and quantify STH eggs in stool samples. We have assessed this assay by measuring infection prevalence and intensity in field samples of two cohorts of participants from Timor-Leste and Cambodia, which were collected as part of earlier epidemiological studies. MT-PCR diagnostic parameters were compared to a previously published multiplexed qPCR for STH detection. The MT-PCR assay agreed strongly with qPCR data and showed a diagnostic specificity of 99.60-100.00% (sensitivity of 83.33-100.00%) compared to qPCR and kappa agreement exceeding 0.85 in all tests. In addition, the MT-PCR has the added advantage of distinguishing Ancylostoma spp. species, namely Ancylostoma duodenale and Ancylostoma ceylanicum. This semi-automated platform uses a standardized, manufactured reagent kit, shows excellent run-to-run consistency/repeatability and supports high-throughput detection and quantitation at a moderate cost.