Intestinal parasites: Associations with intestinal and systemic inflammation

The aim of the present study was to evaluate associations between intestinal parasitic infection with intestinal and systemic inflammatory markers in school-aged children with high rates of obesity. Plasma concentrations of C-Reactive Protein (CRP), leptin, TNF-α, IL-6 and IL-10 were measured as systemic inflammation markers and count of stool leukocytes as marker of intestinal inflammation in 291 children (6-10 years). Intestinal parasitic infection was measured by stool examination. Logistic regression analyses were performed to determine the odds of having high inflammatory markers for each parasite or group of parasites as compared to parasite-free children while adjusting for sex, age, mother's educational level and percentage of body fat. The prevalence of soil-transmitted helminths and intestinal protozoa infections was 12% and 36%, respectively. Parasitic infection was not associated with CRP, IL-6, IL-10 or TNF-α. Children infected with Ascaris lumbricoides (aOR: 5.91, 95% CI: 1.97-17.70) and Entamoeba coli (aOR: 8.46, 95% CI: 2.85-25.14) were more likely to have higher stool leucocytes than parasite-free children. Children with multiple infections (aOR: 10.60, 95% CI: 2.85-25.14) were more likely to have higher leptin concentrations than parasite-free children. Intestinal parasitic infection was not associated with systemic inflammation, but was associated with intestinal inflammation. Having multiple infections were associated with higher leptin concentrations.

Intestinal parasite infections in a rural community of Rio de Janeiro (Brazil): Prevalence and genetic diversity of Blastocystis subtypes

Background

Intestinal parasitic infections are considered a serious public health problem and widely distributed worldwide, mainly in urban and rural environments of tropical and subtropical countries. Globally, soil-transmitted helminths and protozoa are the most common intestinal parasites. Blastocystis sp. is a highly prevalent suspected pathogenic protozoan, and considered an unusual protist due to its significant genetic diversity and host plasticity.

Methodology/main findings

A total of 294 stool samples were collected from inhabitants of three rural valleys in Rio de Janeiro, Brazil. The stool samples were evaluated by parasitological methods, fecal culture, nested PCR and PCR/Sequencing. Overall prevalence by parasitological analyses was 64.3% (189 out of 294 cases). Blastocystis sp. (55.8%) was the most prevalent, followed by Endolimax nana (18.7%), Entamoeba histolytica complex (7.1%), hookworm infection (7.1%), Entomoeba coli (5.8%), Giardia intestinalis (4.1%), Iodamoeba butchilii (1.0%), Trichuris trichiura (1.0%), Pentatrichomonas hominis (0.7%), Enterobius vermicularis (0.7%), Ascaris lumbricoides (0.7%) and Strongyloides stercoralis (0.7%). Prevalence of IPIs was significantly different by gender. Phylogenetic analysis of Blastocystis sp. and BLAST search revealed five different subtypes: ST3 (34.0%), ST1 (27.0%), ST2 (27.0%), ST4 (3.5%), ST8 (7.0%) and a non-identified subtype.

Conclusions/significance

Our findings demonstrate that intestinal parasite infection rates in rural areas of the Sumidouro municipality of Rio de Janeiro, Brazil are still high and remain a challenge to public health. Moreover, our data reveals significant genetic heterogeneity of Blastocystis sp. subtypes and a possible novel subtype, whose confirmation will require additional data. Our study contributes to the understanding of potential routes of transmission, epidemiology, and genetic diversity of Blastocystis sp. in rural areas both at a regional and global scale.

Differential human gut microbiome assemblages during soil-transmitted helminth infections in Indonesia and Liberia

BACKGROUND

The human intestine and its microbiota is the most common infection site for soil-transmitted helminths (STHs), which affect the well-being of ~ 1.5 billion people worldwide. The complex cross-kingdom interactions are not well understood.

RESULTS

A cross-sectional analysis identified conserved microbial signatures positively or negatively associated with STH infections across Liberia and Indonesia, and longitudinal samples analysis from a double-blind randomized trial showed that the gut microbiota responds to deworming but does not transition closer to the uninfected state. The microbiomes of individuals able to self-clear the infection had more alike microbiome assemblages compared to individuals who remained infected. One bacterial taxon (Lachnospiracae) was negatively associated with infection in both countries, and 12 bacterial taxa were significantly associated with STH infection in both countries, including Olsenella (associated with reduced gut inflammation), which also significantly reduced in abundance following clearance of infection. Microbial community gene abundances were also affected by deworming. Functional categories identified as associated with STH infection included arachidonic acid metabolism; arachidonic acid is the precursor for pro-inflammatory leukotrienes that threaten helminth survival, and our findings suggest that some modulation of arachidonic acid activity in the STH-infected gut may occur through the increase of arachidonic acid metabolizing bacteria.

CONCLUSIONS

For the first time, we identify specific members of the gut microbiome that discriminate between moderately/heavily STH-infected and non-infected states across very diverse geographical regions using two different statistical methods. We also identify microbiome-encoded biological functions associated with the STH infections, which are associated potentially with STH survival strategies, and changes in the host environment. These results provide a novel insight of the cross-kingdom interactions in the human gut ecosystem by unlocking the microbiome assemblages at taxonomic, genetic, and functional levels so that advances towards key mechanistic studies can be made.

Group 2 ILCs: A way of enhancing immune protection against human helminths?

Group 2 innate lymphoid cells (ILC2s) play crucial roles in type 2 immune responses associated with allergic and autoimmune diseases, viral and helminth infections and tissue homoeostasis. Experimental models show that in helminth infections ILC2s provide an early source of type 2 cytokines and therefore are essential for the induction of potentially protective type 2 responses. Much of our knowledge of ILC2s in helminth infections has come from experimental mouse models with very few studies analysing ILC2s in natural human infections. In attempts to harness knowledge from paradigms of the development of protective immunity in human helminth infections for vaccine development, the role of ILC2 cells could be pivotal. So far, potential vaccines against human helminth infections have failed to provide effective protection when evaluated in human studies. In addition to appropriate antigen selection, it is apparent that more detailed knowledge on mechanisms of induction and maintenance of protective immune responses is required. Therefore, there is need to understand how ILC2 cells induce type 2 responses and subsequently support the development of a protective immune response in the context of immunizations. Within this review, we summarize the current knowledge of the biology of ILC2s, discuss the importance of ILC2s in human helminth infections and explore how ILC2 responses could be boosted to efficiently induce protective immunity.

New paleoparasitological investigations from the pre-inca to hispanic contact period in northern Chile

Paleoparasitological studies have demonstrated that changes in environment or culture are reflected in the patterns of parasitic infection diseases in populations worldwide. The advent of agriculture and animal domestication, with its accompanying reduction in human mobility and expanding population involves changes in or emergence of, parasites, the so-called first epidemiological transition. Cultural processes related to territory occupation contribute to both loss and acquisition of parasites. The archaeological site Lluta 57 in the Lluta Valley, Chile, provides a chronology of the transition from the pre-Inca or Late Intermediate Period (LIP), through the Late or Inca Period (LP), to the Hispanic Contact Period (HCP), providing the possibility of evaluating this epidemiological transition. The aim of this study was to conduct a paleoparasitological investigation of to gain insight into the dynamics of parasitism in Lluta people throughout the Inca expansion. Fourteen human coprolites from the three periods were rehydrated, submitted to spontaneous sedimentation, and examined by light microscopy for the presence of intestinal parasite eggs, pollen grains, and micro-remains. Eggs of four parasites: Enterobius vermicularis, Trichostrongylus sp., Trichuris sp., and Eimeria macusaniensis were recovered. Frequency, diversity, and number of parasite eggs per sample increased over the studied time period. Trichostrongylus sp. and E. macusaniensis were recorded in the region for the first time. Enterobius vermicularis eggs, absent in the LIP, were present as a hyper-infection in LP. The presence of E. macusaniensis is likely related to exploitation of llamas, which were used for food and transport and as sacrificial offerings. The paleobotanical analysis revealed ten families of pollen grains, as well as phytoliths and floral remains. In contrast to parasitological results, a diachronic pattern was not detected. Evolution of the settlements, with the advent of larger, more densely populated, villages, could have influenced the emergence and intensification of transmission of parasites in the region. The study showed that the Inca expansion influenced host-parasite-environment relationships in the Lluta Valley.

Current epidemiological evidence for predisposition to high or low intensity human helminth infection: a systematic review

BACKGROUND

The human helminth infections include ascariasis, trichuriasis, hookworm infections, schistosomiasis, lymphatic filariasis (LF) and onchocerciasis. It is estimated that almost 2 billion people worldwide are infected with helminths. Whilst the WHO treatment guidelines for helminth infections are mostly aimed at controlling morbidity, there has been a recent shift with some countries moving towards goals of disease elimination through mass drug administration, especially for LF and onchocerciasis. However, as prevalence is driven lower, treating entire populations may no longer be the most efficient or cost-effective strategy. Instead, it may be beneficial to identify individuals or demographic groups who are persistently infected, often termed as being "predisposed" to infection, and target treatment at them.

METHODS

The authors searched Embase, MEDLINE, Global Health, and Web of Science for all English language, human-based papers investigating predisposition to helminth infections published up to October 31st, 2017. The varying definitions used to describe predisposition, and the statistical tests used to determine its presence, are summarised. Evidence for predisposition is presented, stratified by helminth species, and risk factors for predisposition to infection are identified and discussed.

RESULTS

In total, 43 papers were identified, summarising results from 34 different studies in 23 countries. Consistent evidence of predisposition to infection with certain species of human helminth was identified. Children were regularly found to experience greater predisposition to Ascaris lumbricoides, Schistosoma mansoni and S. haematobium than adults. Females were found to be more predisposed to A. lumbricoides infection than were males. Household clustering of infection was identified for A. lumbricoides, T. trichiura and S. japonicum. Ascaris lumbricoides and T. trichiura also showed evidence of familial predisposition. Whilst strong evidence for predisposition to hookworm infection was identified, findings with regards to which groups were affected were considerably more varied than for other helminth species.

CONCLUSION

This review has found consistent evidence of predisposition to heavy (and light) infection for certain human helminth species. However, further research is needed to identify reasons for the reported differences between demographic groups. Molecular epidemiological methods associated with whole genome sequencing to determine 'who infects whom' may shed more light on the factors generating predisposition.

Library Preparation for ATAC-Sequencing of Mouse CD4+ T Cells Isolated from the Lung and Lymph Nodes After Helminth Infection

Although conventional methods such as MNase-seq, DNase-seq, and ChIP-seq have been used effectively to assess chromatin and locus accessibility at the genome level, these techniques generally require large numbers of input cells. As such, much of what we understand in terms of epigenetic regulation and locus accessibility in CD4+ T cell subsets comes from in vitro culture systems, which allow for the production of large numbers of polarized T cells. However, obtaining such numbers directly ex vivo from tissues of individual mice is difficult. Here we describe a method combining cytokine reporter mice and Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) to identify genome wide locus accessibility in a small number of cytokine-expressing CD4+ T cells. This method takes you from cell isolation to library generation and quality control to query. Because the Il4 and Ifng loci are reciprocally regulated in polarized CD4+ T cell subsets (Th1 vs. Th2), we investigated the ability of this approach to identify transposase integration in both IL-4- and IFN-γ-expressing CD4+ T cells isolated directly from the lung and lymph nodes after helminth infection.

Assessing the Mouse Intestinal Microbiota in Settings of Type-2 Immune Responses

The microbial communities that reside within the mammalian host play important roles in the development of a robust host immune system. With the advent of sequencing technology and barcoding strategy of the bacterial 16S ribosomal RNA (rRNA) gene, microbiota studies are becoming more economical but also more important in many immunology studies. Here, we described a representative study protocol to characterize how the microbiota changes during an intestinal helminth infection, with emphasis on subtle aspects of the experimental design that are critical for data interpretation.

Anthropometric Indices and Serum Micronutrient Status of Helminth - Infected School Children from Semi-Urban Communities in Southwestern Nigeria

Adequate nutrition is essential for normal growth of children but helminth infection is proposed to cause nutritional deficiencies. This study was carried out to assess the nutritional status of helminth infected school aged children in semi-urban communities of South-West Nigeria. Two hundred children from primary schools in Akinyele Local Government of Oyo State, Nigeria participated in the study. Anthropometric measurements were analyzed using the WHO AnthroPlus software. Kato Katz method was used to detect ova of helminths in the stool while serum levels of iron, zinc, selenium, ferritin, transferrin, vitamin A, vitamin C and haptoglobin were measured using High Performance Liquid Chromatography and Atomic Absorption Spectophotometry as appropriate. 60 (30%) of the children had intestinal helminth infection with Ascaris lumbricoides (23.0%) as most prevalent, followed by hookworm (2.5%) and Trichuris trichuria (0.5%).  Stunting was more prevalent than thinness or underweight among the study population especially the female children. There were significantly reduced serum levels of zinc and vitamin A and significantly increased serum levels of transferrin and selenium in helminth-infected children compared with helminth-uninfected children. This study established the need for regular deworming of school age children and supplementing diets of school children in rural communities with vitamin A and zinc.

Helminth log reduction values for recycling water from sewage for the protection of human and stock health

The LRVs required to decrease HE concentrations in raw sewage to an acceptable level to manage the risk to human and livestock health were determined. An LRV of 3.0 was required to meet the HBT of 1 μDALY pppy in SE Australia where human helminth infections are not endemic. In comparison, a similar exposure volume and LRV in endemic regions would result in a HBT of 100 μDALY pppy. The risks posed by cattle- and pig-related helminths were also managed acceptably with the treatment of sewage providing an LRV of 3.0. New design equations were derived to determine LRVs based on hydraulic residence times (HRTs) in an activated sludge plant (ASP) and lagoons. The new equation for lagoons indicated that an LRV of 3.0 could be achieved with a HRT of 18 days or less.

Systematic review of studies generating individual participant data on the efficacy of drugs for treating soil-transmitted helminthiases and the case for data-sharing

Background

Preventive chemotherapy and transmission control (PCT) by mass drug administration is the cornerstone of the World Health Organization (WHO)’s policy to control soil-transmitted helminthiases (STHs) caused by Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm) and hookworm species (Necator americanus and Ancylostama duodenale) which affect over 1 billion people globally. Despite consensus that drug efficacies should be monitored for signs of decline that could jeopardise the effectiveness of PCT, systematic monitoring and evaluation is seldom implemented. Drug trials mostly report aggregate efficacies in groups of participants, but heterogeneities in design complicate classical meta-analyses of these data. Individual participant data (IPD) permit more detailed analysis of drug efficacies, offering increased sensitivity to identify atypical responses potentially caused by emerging drug resistance.

Methodology

We performed a systematic literature review to identify studies concluding after 2000 that collected IPD suitable for estimating drug efficacy against STH. We included studies that administered a variety of anthelmintics with follow ups less than 60 days after treatment. We estimated the number of IPD and extracted cohort- and study-level meta-data.

Principal findings

We estimate that there exist individual data on approximately 35,000 participants from 129 studies conducted in 39 countries, including 34 out of 103 countries where PCT is recommended. We find significant heterogeneity in diagnostic methods, times of outcome assessment, and the reported measure of efficacy. We also quantify cohorts comprising pre-school age children, pregnant women, and co-infected participants, including with HIV.

Conclusions

We argue that establishing a global IPD repository would improve the capacity to monitor and evaluate the efficacy of anthelmintic drugs, respond to changes and safeguard the ongoing effectiveness of PCT. Establishing a fair, transparent data governance policy will be key for the engagement of the global STH community.

Soil-transmitted helminthiases (STHs) caused by roundworm, whipworm or hookworm affect over one billion of the world’s poorest people mostly living in low and middle income countries, exerting a major health and economic toll. These infections are controlled by regular mass drug distribution to affected populations. But with very few alternative medicines, the effectiveness of treatment programmes is vulnerable to the potential emergence of drug resistance. Despite a recent scale-up of mass drug distribution, systematic monitoring and evaluation of the efficacy of treatment is too rarely undertaken and our knowledge of how the drugs are performing is largely based on information from clinical trials. However, the design and reporting of information from these trials is very variable which makes it difficult to form a comprehensive picture of the status and trends in drug efficacy. Here, we present a systematic review of published studies completed since 2000, characterise variation in their design, implementation and reporting and estimate the abundance of individual participant data. We argue that the co-ordinated sharing of these individual data would greatly increase the capacity of the global health community to monitor effectively drug efficacy, to respond accordingly to changes, and thereby to safeguard the effectiveness of STH control.

Infections by human gastrointestinal helminths are associated with changes in faecal microbiota diversity and composition

Investigations of the impact that patent infections by soil-transmitted gastrointestinal nematode parasites exert on the composition of the host gut commensal flora are attracting growing interest by the scientific community. However, information collected to date varies across experiments, and further studies are needed to identify consistent relationships between parasites and commensal microbial species. Here, we explore the qualitative and quantitative differences between the microbial community profiles of cohorts of human volunteers from Sri Lanka with patent infection by one or more parasitic nematode species (H+), as well as that of uninfected subjects (H-) and of volunteers who had been subjected to regular prophylactic anthelmintic treatment (Ht). High-throughput sequencing of the bacterial 16S rRNA gene, followed by bioinformatics and biostatistical analyses of sequence data revealed no significant differences in alpha diversity (Shannon) and richness between groups (P = 0.65, P = 0.13 respectively); however, beta diversity was significantly increased in H+ and Ht when individually compared to H-volunteers (P = 0.04). Among others, bacteria of the families Verrucomicrobiaceae and Enterobacteriaceae showed a trend towards increased abundance in H+, whereas the Leuconostocaceae and Bacteroidaceae showed a relative increase in H- and Ht respectively. Our findings add valuable knowledge to the vast, and yet little explored, research field of parasite—microbiota interactions and will provide a basis for the elucidation of the role such interactions play in pathogenic and immune-modulatory properties of parasitic nematodes in both human and animal hosts.

A cross-sectional survey of soil-transmitted helminthiases in two Myanmar villages receiving mass drug administration: epidemiology of infection with a focus on adults

BACKGROUND

Soil-transmitted helminths (STH) are still highly prevalent in southeast Asia. The country of Myanmar has had ongoing mass drug administration (MDA) programmes since 2003 in an attempt to control STH and reduce STH-related morbidities. Whilst the MDA programmes have reported high nationwide coverage, there have been no epidemiological surveys that included measurements from adults. This paper details three cross-sectional surveys that took place over the course of a year in two villages endemic for STH and receiving MDA in lower Myanmar.

RESULTS

At baseline, 27.81% of participants were infected with at least one type of STH. The most prevalent STH was Trichuris trichiura (18.12%) followed by hookworm (8.71%) and Ascaris lumbricoides (5.34%). Most infections were of low intensity, measured by eggs per gram of faeces (EPG). Gender stratification revealed that A. lumbricoides prevalence was significantly higher in females, whereas hookworm prevalence was significantly higher in males. The distribution of EPG in the study sample was highly overdispersed, suggesting that most people release few eggs whereas a few people release many eggs. Adults harbour a major proportion of the overall STH burden; 65.15% of STH infections were harboured by adults.

CONCLUSIONS

STH infection remains at medium prevalence in the study villages despite past and recent MDA. Recorded prevalence of STH in school-aged children has not substantially decreased since the last monitoring and evaluation activities in Myanmar in 2013. Analyses suggest that adults are a major contributor to the total STH prevalence and EPG burden, probably perpetuating transmission.

Prevalence and intensity of soil transmitted helminths among school children of Mendera Elementary School, Jimma, Southwest Ethiopia

INTRODUCTION

Soil transmitted helminths are wide spread in developing countries and in Ethiopia the prevalence of STHs varies in different parts of the country. The aim of this study was to determine the prevalence and intensity of soil transmitted helminths among school children of Mendera Elementary School Jimma town, Southwestern Ethiopia.

METHODS

A cross-sectional study was conducted between March 29 and April 9, 2010 to determine the prevalence and intensity of soil transmitted helminths among elementary school children. The study participants were randomly selected from class enrollment list after proportional allocation of the total sample size to each grade. Data about the background characteristics were collected using structured questionnaire. The stool samples were examined by McMaster method for the egg count which was used to determine intensity of infection. Data were analyzed using SPSS for windows version 16 and p-value less than 5% was considered as statistically significant.

RESULTS

Of the total 715 stool specimens examined, 346 were positive for at least one intestinal parasite making the prevalence 48.4%. The most prevalent parasites were Ascaris lumbricoides 169 (23.6%) and Trichuris trichiura 165 (23.1%). The prevalence of soil transmitted helminth in this study was 45.6% (326/715). There was statistically significant difference in the prevalence of Trichuriasis between those who use latrine always and who use sometimes (p = 0.010). Females are two times more likely to be positive for Ascaris than males (p = 0.039). Majority of the students had light infection of soil transmitted helminths and none of them had heavy intensity of infection of Trichuriasis and hookworms.

CONCLUSION

Nearly half of the school children were infected with at least one STHs and majority of the students had light infection of soil transmitted helminths. Students who did not wash their hands after defecation were three times more likely to be positive for Ascaris infection than those who washed their hands after defecation. Therefore, measures like health information dissemination on the advantage of washing hands after defecation and on proper use of latrine should be taken into account to alleviate the problem.

The role of domestic dogs in the transmission of zoonotic helminthes in a rural area of Mekong river basin

Dogs have been bred since ancient times for companionship, hunting, protection, shepherding and other human activities. Some canine helminth parasites can cause significant clinical diseases in humans as Opisthorchis viverrini causing cholangiocarcinoma in Southeast Asian Countries. In this study, socio-cultural questionnaire, canine parasitological analysis, necropsy, parasite molecular confirmation and dog roaming data were evaluated in Savannakhet, Lao-PDR, a typical Mekong Basin area. Dog owners comprised 48.8% of the studied population, with 61.2% owning one dog, 25.1% 2 dogs, 8.5% 3 dogs and 1.8% owning more than 4 dogs. Data from GPS logger attached to dogs showed they walked from 1.4 to 13.3 km per day, covering an area of 3356.38m2 average, with a routine of accessing water sources. Thirteen zoonotic helminth species were observed. Causative agents of visceral and cutaneous larva migrans occurred in 44.1% and 70% of the samples respectively. Spirometra erinaceieuropaei was detected in 44.1% of samples. Importantly, O. viverrini was found in 8.8% of samples. Besides the known importance of dogs in the transmission of Ancylostoma spp., Toxocara spp. and S. erinaceieuropaei, the observed roaming pattern of dogs confirmed it as an important host perpetuating O. viverrini in endemic areas; their routine access to waterbodies may spread O. viverrini eggs in a favorable environment for the fluke development, facilitating the infection of fishes, and consequently infecting humans living in the same ecosystem. Therefore, parasitic NTDs control programs in humans should be done in parallel with parasite control in animals, especially dogs, in the Mekong River basin area.

Prevalence of intestinal parasitoses detected in Padua teaching hospital, Italy, March 2011 - February 2013

The aim of this study was to evaluate the distribution of parasitic intestinal infections in patients attending Padua teaching hospital during a two-year period. Between 1st March 2011 and 28th February 2013, we examined stool specimens from 7341 patients (6127 Italians, 1214 non-Italians) for ova and parasites using microscopy, rapid enzyme immunoassays, culture techniques and molecular methods. Stools of 1080 patients (14.71%) were positive for parasites; a total of 1349 intestinal parasites were counted. Protozoa were detected in 1028/1080 patients (95.19%), while helminths were present in 80/1080 patients (7.41%). The protozoa most commonly detected were Blastocystis spp., Dientamoeba fragilis and Giardia duodenalis. Enterobius vermicularis was the helminth most frequently encountered. Of the 1080 infected patients, 227 (21.02%) had more than one parasite in their stool. To conclude, in Italy intestinal parasitoses must be unquestionably considered in differential diagnoses of gastrointestinal diseases. For this purpose, sound knowledge of epidemiology is essential.

Association of enteric parasitic infections with intestinal inflammation and permeability in asymptomatic infants of São Tomé Island

The cumulative effect of repeated asymptomatic enteric infections on intestinal barrier is not fully understood in infants. We aimed to evaluate the association between previous enteric parasitic infections and intestinal inflammation and permeability at 24-months of age, in asymptomatic infants of São Tomé Island. A subset of infants from a birth cohort, with intestinal parasite evaluations in at least four points of assessment, was eligible. Intestinal inflammatory response and permeability were assessed using fecal S100A12 and alpha-1-antitrypsin (A1AT), respectively. The cutoff <-1SD for weight-for-length and length-for-age was used to define wasting and stunting. Multivariable linear regression analysis explored if cumulative enteric parasitic infections explained variability of fecal biomarkers, after adjusting for potential confounders. Eighty infants were included. Giardia duodenalis and soil-transmitted helminths (STH) were the most frequent parasites. The median (interquartile range) levels were 2.87 μg/g (2.41-3.92) for S100A12 and 165.1 μg/g (66.0-275.6) for A1AT. Weak evidence of association was found between S100A12 levels and G. duodenalis (p = 0.080) and STH infections (p = 0.089), and between A1AT levels and parasitic infection of any etiology (p = 0.089), at 24-months of age. Significant associations between A1AT levels and wasting (p = 0.006) and stunting (p = 0.044) were found. Previous parasitic infections were not associated with fecal biomarkers at 24 months of age. To summarize, previous asymptomatic parasitic infections showed no association with intestinal barrier dysfunction. Notwithstanding, a tendency toward increased levels of the inflammatory biomarker was observed for current G. duodenalis and STH infections, and increased levels of the permeability biomarker were significantly associated with stunting and wasting.

Investigations into the association between soil-transmitted helminth infections, haemoglobin and child development indices in Manufahi District, Timor-Leste

BACKGROUND

Timor-Leste has a high prevalence of soil-transmitted helminth (STH) infections. High proportions of the population have been reported as being anaemic, and extremely high proportions of children as stunted or wasted. There have been no published analyses of the contributions of STH to these morbidity outcomes in Timor-Leste.

METHODS

Using baseline cross-sectional data from 24 communities (18 communities enrolled in a cluster randomised controlled trial, and identically-collected data from six additional communities), analyses of the association between STH infections and community haemoglobin and child development indices were undertaken. Stool samples were assessed for STH using qPCR and participant haemoglobin, heights and weights were measured. Questionnaires were administered to collect demographic and socioeconomic data. Intensity of infection was categorised using correlational analysis between qPCR quantification cycle values and eggs per gram of faeces equivalents, with algorithms generated from seeding experiments. Mixed-effects logistic and multinomial regression were used to assess the association between STH infection intensity classes and anaemia, and child stunting, wasting and underweight.

RESULTS

Very high stunting (60%), underweight (60%), and wasting (20%) in children, but low anaemia prevalence (15%), were found in the study communities. STH were not significantly associated with morbidity outcomes. Male children and those in the poorest socioeconomic quintile were significantly more likely to be moderately and severely stunted. Male children were significantly more likely than female children to be severely underweight. Increasing age was also a risk factor for being underweight. Few risk factors emerged for wasting in these analyses.

CONCLUSIONS

According to World Health Organization international reference standards, levels of child morbidity in this population constitute a public health emergency, although the international reference standards need to be critically evaluated for their applicability in Timor-Leste. Strategies to improve child development and morbidity outcomes, for example via nutrition and iron supplementation programmes, are recommended for these communities. Despite the apparent lack of an association from STH in driving anaemia, stunting, wasting and underweight, high endemicity suggests a need for STH control strategies.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ACTRN12614000680662 ; retrospectively registered.

Endomyocardial involvement in asymptomatic sub-Saharan immigrants with helminth-related eosinophilia

Background

Among immigrants of sub-Saharan origin, parasitic infection is the leading cause of eosinophilia, which is generally interpreted as a defense mechanism. A side effect of the inflammatory mediators released by eosinophils is damage to host organs, especially the heart. The main objectives of this study were to i) assess cardiac involvement in asymptomatic sub-Saharan immigrants with eosinophilia, ii) relate the presence of lesions with the degree of eosinophilia, and iii) study the relationship between cardiac involvement and the type of causative parasite.

Methodology/Principle findings

In total, the study included 50 black immigrants (37 patients and 13 controls) from sub-Saharan Africa. In all subjects, heart structure and function were evaluated in a blinded manner using Sonos 5500 echocardiographic equipment. The findings were classified and described according to established criteria. The diagnostic criteria for helminthosis were those reported in the literature. Serum eosinophil-derived neurotoxin levels were measured using enzyme-linked immunosorbent assay. A significant association was found between the presence of eosinophilia and structural alterations (mitral valve thickening). However, the lack of an association between the degree of eosinophilia and heart valve disease and the absence of valve involvement in some patients with eosinophilia suggest the role of other factors in the appearance of endocardial lesions. There was also no association between the type of helminth and valve involvement.

Conclusions

We, therefore, suggest that transthoracic echocardiography be performed in every sub-Saharan individual with eosinophilia in order to rule out early heart valve lesions.

Endomyocardial fibrosis is characterized by fibrosis of the apical endocardium of the right ventricle, left ventricle, or both. Epidemiological studies of endomyocardial fibrosis indicate a predominance in tropical regions, with young people and men being affected predominantly. Little is known about the natural history and pathogenic factors of this condition. One of the most important factors is the presence of eosinophilia, which is mainly related to helminth infections. The aim of the study was to evaluate cardiac involvement in patients with absolute eosinophilia. We performed an echocardiographic study in asymptomatic sub-Saharan immigrants with eosinophilia and compared them with a group of control patients from the same region and of the same age. Our results suggest that eosinophilia associated with helminth infection (regardless of the causative microorganism) contributes to the asymptomatic phases of endomyocardial involvement. Treatment of these infections is simple, effective, and economical. Therefore, we suggest that all immigrant patients with eosinophilia undergo etiologic study and causal treatment as well as transthoracic echocardiography in order to rule out early damage.

[Diagnosis and treatment of imported eosinophilia in travellers and immigrants: Recommendations of the Spanish Society of Tropical Medicine and International Health (SEMTSI)]

According to published data, prevalence of imported eosinophilia among travellers and immigrants is set between 8% and 28.5%. Etiological diagnosis is often troublesome, and depending on the depth of the study and on the population analyzed, a parasitic cause is identified in 17% to 75.9% of the individuals. Among the difficulties encountered to compare studies are the heterogeneity of the studied populations, the type of data collection (prospective/retrospective) and different diagnostic protocols. In this document the recommendations of the expert group of the Spanish Society of Tropical Medicine and International Health (SEMTSI) for the diagnosis and treatment of imported eosinophilia are detailed.

Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases

Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test.

Effect of Mass Stool Examination and Mass Treatment For Decreasing Intestinal Helminth and Protozoan Infection Rates in Bolivian Children: A Cross-Sectional Study

Bolivia is one of the countries with a high intestinal helminth and protozoan infection rate. Despite the high prevalence of the parasitic infection, nationwide preventive measures for Bolivian children have not yet been implemented. We evaluated the effect of mass stool examination and treatment as a strategy for decreasing the infection rate. This study was conducted between 2013 and 2015 in children aged 2–18 years. A total of 2,033 stool samples (575 in 2013, 815 in 2014 and 642 in 2015) were collected and examined using the formalin-ether medical sedimentation method. As an anthelminthic medicine, nitazoxanide was given to all infected children within 2 months post-examination, each year. The effect of mass stool examination and treatment was evaluated based on the changes in the overall or individual parasitic infection rates during the study period. The overall parasitic infection rate decreased significantly from 65.2% in 2013 to 43.0% in 2015; a 22.2 percentage point decrease (P<0.001). Protozoan infection accounted for a large portion of the parasitic infections, in the following rates: 62.4% in 2013, 49.3% in 2014, and 41.0% in 2015. The rate of the most common helminth infection, Hymenolepis nana, decreased significantly from 9.0% in 2013 to 6.4% in 2014 to 3.4% in 2015 (P<0.001). Prevalence of the most common pathogenic protozoan infection, Entamoeba histolytica, decreased significantly from 19.0% in 2013 to 3.0% in 2015 (P<0.001). Conversely, the rate of Giardia intestinalis increased significantly from 16.5% in 2013 to 21.2% in 2015 (P<0.01). Mass stool examination and treatment for intestinal helminth and protozoan infections was effective for decreasing the overall parasitic infection rate in the study population, excluding Giardia intestinalis. Further studies on the long-term effect of mass stool examination and treatment for decreasing all intestinal parasitic infection rates in Bolivian children are needed.

Intestinal helminth and protozoan (parasitic) infections are found mainly in areas with warm, humid climates and in many developing countries. Bolivia currently has high parasite infection rates, including intestinal helminth and protozoan infections. Despite the high prevalence of parasitic infections, nationwide preventive measures for Bolivian children have not yet been implemented. Soil-transmitted helminth infection rates in Japan decreased sharply through practice of health education, mass stool examination and treatment. We investigated the effects of mass stool examination and treatment on parasitic infection rates in Bolivian children. Mass stool examination was performed using the formalin-ether medical sedimentation method between 2013 and 2015, and all infected children were administrated anthelminthic medicine within 2 months post-examination. During the study period, the overall infection rate decreased significantly, but Giardia intestinalis infection rate increased. This may have been related to the interval between treatment and examination. To decrease infection rates for all parasites, the treatment should be performed once or twice a year. Our results suggest that a program of mass stool examination and treatment could effectively reduce the overall parasite-infection rate in Bolivian children.

COMPARISON BETWEEN KATO-KATZ THICK SMEAR AND SEDIMENTATION TECHNIQUES IN DIAGNOSIS OF FAECAL-ORALLY TRANSMITTED HELMINTHES AND OTHER GEOHELMINTHES

Kato-Katz technique is widely used for the diagnosis of Fecal-orally transmitted helminthic infections. It is relatively simple and inexpensive. However, a single slide prepared from a single stool specimen has low sensitivity, particularly in light infections. Therefore, there is a great need for concentration techniques. This study detected an accurate and affordable method for diagnosis of fecal-orally transmitted helminthes and other geohelminthes. The study was carried out on 217 stool samples of different sex and age groups. Stool samples were collected from different urban and rural areas in Sharkia Governorate. Stool samples were examined macroscopically and analyzed by different parasitological techniques: direct wet mount (DWM), Kato-Katz thick smear, spontaneous sedimentation in tube technique (SSTT) and formol ether sedimentation technique (FEC). The results showed that formol ether sedimentation method detected 59 positive samples followed by spontaneous sedimentation in tube technique (48/59 positive samples). FEC showed significant difference when compared to direct wet mount and Kato-Katz thick smear. SSTT also showed significant difference when compared to DWM (P <0.05).The overall prevalence of intestinal helminthes was (29.6%) among studied samples in Sharkia Governorate. The commonest helminthic infection was H. nana (12%) followed by E. vemicularis(10%) then A. lumbricoides (3.7%).

THE PARASITIC PROFILE AMONG SCHOOL CHILDREN IN EI-WADI EL-GADDED GOVERNORATE, EGYPT

Parasitic infection is still a serious public health problem in the world, especially in developing countries including Egypt. It represents a major cause of morbidity and mortality in childhood and among high-risk groups-in most parts of the world. This study detected the prevalence of parasitic infection among school children in-El-Wadi El-Gadded (the New Valley Governorate). A total of randomly chosen 1615 students aged from 6-16 years, (771 males & 844 female) from 12 primary schools and 12 preparatory schools related to four centers (El Dakhala, El Farfra, Paris and Platt) from the New Valley. Governorate. Each child was subject to: A questionnaire sheet, Urine examination through sedimentation methods, Stool examination using: Direct smear, Simple sedimentation method and Modified Ziehl-Neelsen Stain, Blood samples were collected randomly from 450 children and examined for Seropositivity of toxoplasmosis using (On-SiteToxolgG/IgM Rapid Test- Cassette) and examination of hair & clothes for ectoparasites (lice). The overall prevalence of parasites was (39.1%) among primary and preparatory school children. The helminthes were E. vermicularis (15.2% & 17.1%); A. lumbricoides (1.3% & 1.9%) and then H. nana (0.9% & 0.6%) and the protozoa were E. histolytica (14.1% & 13.2%), Giardia lamblia (3.8% & 3.9%), and then Cryptosporidium parvum (0.09%) and seropositivity of toxoplasmosis was in (3.0% & 2.7%) among primary and preparatory school children respectively. Mixed infection was in (0.4%) among primary school children. Head lice infestaiion was more prevalent among primary school children than preparatory school ones with a ratio (3.5% &0.2%) respectively, was nil among males.

PARASITOLOGICAL STUDIES ON SOME INTESTINAL PARASITES IN PRIMARY SCHOOL CHILDREN IN ASWAN GOVERNORATE, EGYPT

This cross sectional study in Aswan Governorate determined the prevalence of intestinal parasites and to identify the risk factors for infection in primary school children in this geographical area. The results would facilitate evaluation of the endemic level of different intestinal parasites and the determination of whether wiqespread or focal measures of parasite control are required. After obtaining official permission from the school administration, information and consent forms were given to the parents of all the schoolchildren. They were three-hundreds children aged between 6-12 year were enrolled; a detailed questionnaire, complete clinical assessment complete as well as stool analysis was done The study showed that the over-all infection was 31%, single parasitic infection was 26% and mixed one was 5%.The commonest helminthic infection was E. vermicularis 6.6% followed by H. nana 3% Ascaris lumbricoidesl%. The commonest protozoa infection was E. histolytica 8.3% followed by Giardia lamblia 3.7% and Cryptosporidium parvum 1.7%. Mixed infection was E. vernficularis plus E. histolytica (23.4%), E vermicularis plus G. lamblia (17.6%), E. vermicularis plus C. parvum (11.8%), E. histolytica plus H. nana (11.85%), A. -lumbricoides plus E. histolytica (17.6%) and G. lamblia plus E. histolytica in (11.8%). Parasitic infection was more prevalent in boys (53.8%) than girls (46.2%) and more prevalent in rural children (39.73%) than urban ones (20.13%) among age ranged from 6 to 12 years (8.97±1.72).

[FIRST RECORD OF RHADINORHYNCHUS COLOLABIS (ACANTHOCEPHALA: RHADINORHYNCHIDAE) FROM THE CHERRY SALMON IN THE SEA OF JAPAN]

Drawing, description and characteristics of Rhadinorhynchus cololabis, registered for the first time from Oncorhynchus masou in the Sea of Japan (northern part of Primorye Territory) are given. Ten species of acanthocephalans from the cherry salmon in the Primorsky Territory were recorded.

Spatial distribution of intestinal parasitic infections in a Kaingáng indigenous village from Southern Brazil

The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test(®) and Kato & Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2 % (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8 %) and Trichuris trichiura (44.7 %). The prevalence of heavy infection by soil-transmitted helminths was 3.6 % and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services.

[ECOLOGICAL AND PARASITOLOGICAL CHARACTERISTICS OF THE SMALL REDFISH SEBASTES VIVIPARUS (PISCES: SCORPAENIDAE)]

The results of the parasite fauna research represent peculiarities of formation and ecological, faunistic and zoogeographical characteristics of parasite fauna of the small redfish Sebastes viviparus Krayer. 1845. This species is distinguished among the other North Atlantic Sebastes by the richest fauna of myxosporidians, trematodes, nematodes and acanthocephalans. The parasite fauna of S. viviparus is formed mainly of boreal species and to a lesser extent of Arctic-boreal species. According to the vertical zonality of parasites in fishes of the North Atlantic they are mainly represented by mesobenthic and epicontinental species. The parasite fauna in small redfish possesses significantly more pronounced geographic specificity than that of other North Atlantic Sebastes species.

Gastrointestinal parasites in Ugandan cancer patients: a retrospective departmental review

Of all cancer patients, 28% had gastrointestinal parasites of medical importance.

Soil-Transmitted Helminth Eggs Are Present in Soil at Multiple Locations within Households in Rural Kenya

Almost one-quarter of the world’s population is infected with soil-transmitted helminths (STH). We conducted a study to determine the prevalence and location of STH—Ascaris, Trichuris, and hookworm spp.—egg contamination in soil within rural household plots in Kenya. Field staff collected soil samples from July to September 2014 from the house entrance and the latrine entrance of households in Kakamega County; additional spatial sampling was conducted at a subset of households (N = 22 samples from 3 households). We analyzed soil samples using a modified version of the US Environmental Protection Agency (EPA) method for enumerating Ascaris in biosolids. We found 26.8% of households had one or more species of STH eggs present in the soil in at least one household location (n = 18 out of 67 households), and Ascaris was the most commonly detected STH (19.4%, n = 13 out of 67 households). Prevalence of STH eggs in soil was equally likely at the house entrance (19.4%, N = 67) as at the latrine entrance (11.3%, N = 62) (p = 0.41). We also detected STH eggs at bathing and food preparation areas in the three houses revisited for additional spatial sampling, indicating STH exposure can occur at multiple sites within a household plot, not just near the latrine. The highest concentration of eggs in one house occurred in the child’s play area. Our findings suggest interventions to limit child exposure to household soil could complement other STH control strategies.

Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites

Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

Soil-Transmitted Helminths and Schistosoma mansoni Infections in Ethiopian Orthodox Church Students around Lake Tana, Northwest Ethiopia

BACKGROUND

Soil-transmitted helminths (STH) and Schistosoma mansoni infections are the major neglected tropical diseases that result in serious consequences on health, education and nutrition in children in developing countries. The Ethiopian Orthodox church students, who are called Yekolotemari in Amharic, live in areas with poor sanitation and hygiene. Moreover, they are not included in the national STH control programs. Thus, STH and S. mansoni infections prevalence is unknown.

METHODS

A cross-sectional study was conducted on 384 students in June 2014 to determine STH and S. mansoni infections prevalence. Moreover, the knowledge of students about STH and S. mansoni was assessed. Data on knowledge and clinical symptoms were collected using structured questionnaires via face to face interview. Stool specimens were examined by formol-ether concentration method.

RESULTS

The overall prevalence of intestinal helminths infections was 85.9% (95% confidence interval (CI): 82.1-89%). STHs infections prevalence was 65.6% (95% CI: 60.7-70.2%). The prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura were 31.8% (95% CI: 27.3-36.6%), 29.4% (25-31%) and 3.1% (1.8-5.4%), respectively. On the other hand, S. mansoni prevalence was 14.3% (95% CI: 11.1-18.1%). Majority of students infected with S. mansoni had bloody stool with crud odds-ratio of 2.9 (95% CI: 1.5-5.5). Knowledge assessment showed that 50 (13%) and 18 (4.9%) of the respondents knew about transmission of STH and S. mansoni, respectively.

CONCLUSIONS

The prevalence of STH and S. mansoni infections were high thus de-worming program should include the students of Ethiopian Orthodox churches. Furthermore, provision and use of sanitary facilities, health education for students to create awareness of parasitic infections and improved personal hygiene should be in place.

Complexities and Perplexities: A Critical Appraisal of the Evidence for Soil-Transmitted Helminth Infection-Related Morbidity

BACKGROUND

Soil-transmitted helminths (STH) have acute and chronic manifestations, and can result in lifetime morbidity. Disease burden is difficult to quantify, yet quantitative evidence is required to justify large-scale deworming programmes. A recent Cochrane systematic review, which influences Global Burden of Disease (GBD) estimates for STH, has again called into question the evidence for deworming benefit on morbidity due to STH. In this narrative review, we investigate in detail what the shortfalls in evidence are.

METHODOLOGY/PRINCIPAL FINDINGS

We systematically reviewed recent literature that used direct measures to investigate morbidity from STH and we critically appraised systematic reviews, particularly the most recent Cochrane systematic review investigating deworming impact on morbidity. We included six systematic reviews and meta-analyses, 36 literature reviews, 44 experimental or observational studies, and five case series. We highlight where evidence is insufficient and where research needs to be directed to strengthen morbidity evidence, ideally to prove benefits of deworming.

CONCLUSIONS/SIGNIFICANCE

Overall, the Cochrane systematic review and recent studies indicate major shortfalls in evidence for direct morbidity. However, it is questionable whether the systematic review methodology should be applied to STH due to heterogeneity of the prevalence of different species in each setting. Urgent investment in studies powered to detect direct morbidity effects due to STH is required.

ACANTHOCEPHALANS PROSTHENORCHIS CF. ELEGANS (ARCHIACANTHOCEPHALA: OLIGACANTHORHYNCHIDAE), PARASITES OF PRIMATES IN THE MOSCOW ZOO

Acanthocephalans Prosthenorchis cf. elegans were found in primates in the Moscow Zoo. The larvae of these parasites (cistacanths) were found in cockroaches Blattella germanica that had been captured near aviaries of infected animals. Descriptions and drawings of adult parasites and their larvae are given. Analysis of Prosthenorchis cf. elegans genes ITS 1 rDNA and CO 1 mtDNA shows phylogenetic relations of these parasites with several representatives of the class Archiacanthocephala. The obtained molecular data, however, do not support the monophyly of the family Oligacanthorhynchidae and the order Oligacanthorhynchida.

Kato-Katz and Lumbreras rapid sedimentation test to evaluate helminth prevalence in the setting of a school-based deworming program

The sensitivity of the Kato-Katz test is suboptimal for the evaluation of intestinal helminth prevalence. Moreover, during mass deworming, as helminth egg burden decreases, the sensitivity is likely to decrease. The Lumbreras rapid sedimentation (Lumbreras) is a low-cost non-quantitative test, but may provide useful information in low burden areas. We compared the prevalence of intestinal helminth infections assessed by the Kato-Katz and the Lumbreras rapid sedimentation test on 3 stool specimens from each of 1083 children. The sensitivities were compared using the McNemar paired test. Using the combined outcome of the 3 different stool tests as the standard, Kato-Katz had lower sensitivity than Lumbreras rapid sedimentation tests for Ascaris lumbricoides (85.1% vs. 95.1%, p = 0.03), Hymenolepis nana (77.7% vs. 97.9%, p < 0.01), Trichuris trichura (41.7% vs. 100%, p = 0.01), hookworm (0% vs. 100%, p = 0.01), and Strongyloides stercoralis (0% vs. 88%, p < 0.01). Kato-Katz demonstrated significantly lower sensitivity, missing most T. trichiura, hookworm, and S. stercoralis infections. The combination of Kato-Katz and Lumbreras rapid sedimentation tests enables the detection of more intestinal helminths infections in post-deworming low prevalence areas.

RELMs in the Realm of Helminths

Resistin-like molecule (RELM) proteins are essential for immunity to helminths. Recently, Chen and collaborators identified a dominant role for RELMα over RELMβ in host immunity to Nippostrongylus brasiliensis using a double knockout system. The study highlighted how important and yet divergent the contributions of these proteins are in the control of helminth infections.

Macrobiota - helminths as active participants and partners of the microbiota in host intestinal homeostasis

Important insights have recently been gained in our understanding of the intricate relationship in the intestinal milieu between the vertebrate host mucosal immune response, commensal bacteria, and helminths. Helminths are metazoan worms (macrobiota) and trigger immune responses that include potent regulatory components capable of controlling harmful inflammation, protecting barrier function and mitigating tissue damage. They can secrete a variety of products that directly affect immune regulatory function but they also have the capacity to influence the composition of microbiota, which can also then impact immune function. Conversely, changes in microbiota can affect susceptibility to helminth infection, indicating that crosstalk between these two disparate groups of endobiota can play an essential role in host intestinal immune function and homeostasis.

Tuft cells, taste-chemosensory cells, orchestrate parasite type 2 immunity in the gut

The intestinal epithelium forms an essential barrier between a host and its microbiota. Protozoa and helminths are members of the gut microbiota of mammals, including humans, yet the many ways that gut epithelial cells orchestrate responses to these eukaryotes remain unclear. Here we show that tuft cells, which are taste-chemosensory epithelial cells, accumulate during parasite colonization and infection. Disruption of chemosensory signaling through the loss of TRMP5 abrogates the expansion of tuft cells, goblet cells, eosinophils, and type 2 innate lymphoid cells during parasite colonization. Tuft cells are the primary source of the parasite-induced cytokine interleukin-25, which indirectly induces tuft cell expansion by promoting interleukin-13 production by innate lymphoid cells. Our results identify intestinal tuft cells as critical sentinels in the gut epithelium that promote type 2 immunity in response to intestinal parasites.

Cost-effectiveness of scaling up mass drug administration for the control of soil-transmitted helminths: a comparison of cost function and constant costs analyses

BACKGROUND

The coverage of mass drug administration (MDA) for neglected tropical diseases, such as the soil-transmitted helminths (STHs), needs to rapidly expand to meet WHO's 2020 targets. We aimed to compare use of a cost function to take into account economies of scale to the standard method of assuming a constant cost per treatment when investigating the cost and cost-effectiveness of scaling up a STH MDA programme targeting Ascaris lumbricoides.

METHODS

We fitted a cost function describing how the costs of MDA change with scale to empirical cost data and incorporated it into a STH transmission model. Using this cost function, we investigated the consequences of taking into account economies of scale on the projected cost-effectiveness of STH control, by comparison with the standard method of assuming a constant cost per treatment. The cost function was fitted to economic cost data collected as part of a school-based deworming programme in Uganda using maximum likelihood methods. We used the model to investigate the total reduction in the overall worm burden, the total number of prevalent infection case-years averted, and the total number of heavy infection case-years averted. For each year, we calculated the effectiveness as the difference between the worm burden or number of cases and the number in absence of treatment.

FINDINGS

When using the cost function, the cost-effectiveness of STH control markedly increased as the programme was scaled up. By contrast, the standard method (constant cost per treatment) undervalued this and generated misleading conclusions. For example, when scaling up control in the projected district from 10% to 75% coverage of at-risk school-age children, the cost-effectiveness in terms of prevention of heavy burden infections was projected to increase by over 70% when using the cost function, but decrease by 18% when assuming a constant cost per treatment.

INTERPRETATION

The current exclusion of economies of scale in most economic analyses must be addressed if the most cost-effective policies for the control of neglected tropical diseases are to be formulated. These findings are also relevant to other large-scale disease interventions.

FUNDING

GlaxoSmithKline, Bill & Melinda Gates Foundation, Partnership for Child Development, and Wellcome Trust.

Maternal Helminth Infection Is Associated With Higher Infant Immunoglobulin A Titers to Antigen in Orally Administered Vaccines

BACKGROUND

Many studies have documented lower vaccine efficacy among children in low-income countries, compared with their counterparts in high-income countries. This disparity is especially apparent with respect to oral vaccines such as rotavirus and oral polio vaccines. One potential contributing factor is the presence of maternal antenatal helminth infections, which can modulate the infant's developing immune system.

METHODS

Using a multiplex immunoassay, we tested plasma immunoglobulin A (IgA) or immunoglobulin G (IgG) levels specific for antigens in 9 routinely administered childhood vaccines among 1639 children aged approximately 13 months enrolled in the ECUAVIDA (Ecuador Life) birth cohort study in Ecuador. We compared vaccine responses in 712 children of mothers who tested positive for helminth infections in the last trimester of pregnancy to responses in 927 children of mothers without helminth infection.

RESULTS

Plasma IgA levels specific for antigens in rotavirus vaccine and oral polio vaccine containing poliovirus serotypes 1 and 3 were all significantly higher in children of helminth-infected mothers, compared with children of uninfected mothers. Plasma IgG levels specific for diphtheria, tetanus, pertussis, measles, rubella, and Haemophilus influenzae type b vaccine antigens were comparable between the 2 groups.

CONCLUSIONS

Antenatal maternal helminth infections were not associated with reduced antibody responses to infant vaccines, but rather with modestly increased IgA responses to oral vaccines.

Heavy metals and parasitic geohelminths toxicity among geophagous pregnant women: a case study of Nakuru Municipality, Kenya

Geophagia is defined as deliberate consumption of earths' materials, e.g. soil, clay and soft stones. The practice is widespread among pregnant women, and there are conflicting views as to whether it is beneficial to health or not. Geophagic materials may be a source of micronutrients though the materials may bind the micronutrients thus reducing or hindering their bioavailability in the body. Geophagia is closely associated with geohelminthic infections among pregnant women and heavy metal poisoning, which constitute significant public health problem in many developing countries such as Kenya. In our research, the geophagic materials consumed by the pregnant women were studied. A total of 38 geophagic materials in the possession by different pregnant women were analysed. The collected samples were subjected to standard digestion procedures and analysed for zinc, lead and iron by atomic absorption spectroscopy. Results indicated that the geophagic materials contained elevated levels of Fe at mean concentration value of 80.10 ppm, Pb at 3.28 ppm and Zn 1.81 ppm for a 1.00 g sample. An average of 20 g of the geophagic materials was being consumed per day. Based on the average consumption, the pregnant women were exposed to 65.52 ppm Pb per day, 36.2 ppm Zn per day and 1602 ppm Fe per day. Lead exceeded the WHO-lead exposure limits of 25 ppm/day for pregnant women. The materials were also subjected to microscopic examination for Ascaris lumbricoides, Trichuris trichiura, Taenia Spp., Necator americanus and Ancylostoma duodenale. In conclusion, the women were exposed to heavy metals-iron, zinc and lead, but there was no observable eggs, larvae or adult species of the geohelminths. The key recommendation was that there is need to integrate public health education on geophagia, lead screening and testing with antenatal support care systems. This will enhance maternal and child health, thus reducing infant and maternal morbidity and mortality rates.

Application of a Multiplex Quantitative PCR to Assess Prevalence and Intensity Of Intestinal Parasite Infections in a Controlled Clinical Trial

Background

Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy.

Methodology/Principal Findings

Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections.

Conclusions/Significance

Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and Giardia compared to microscopy, especially in samples exhibiting polyparasitism. The superior performance of multiplex PCR to detect polyparasitism and more accurately determine infection intensity suggests that it is a more appropriate technique for use in epidemiologic studies and for monitoring large-scale intervention trials.

Gastrointestinal parasites including soil-transmitted helminths cause considerable morbidity worldwide, especially in resource-poor communities. Large-scale epidemiologic and treatment efficacy studies are regularly undertaken to determine the optimum ways to reduce or eliminate parasites from endemic communities, thereby reducing the burden of disease. Accurate and sensitive tests for detection of soil transmitted helminths and protozoa are of great importance to the success of such trials. Increasingly recognised is the importance of accurately determine the infection intensity, as morbidity and transmission pressure of helminth infections are directly related this and not just to prevalence. A vast majority of studies use standard microscopy methods which, although well accepted, may not be as accurate as more recently developed molecular techniques such as multiplex PCR. Therefore, there is need for further evaluation of multiplex PCR techniques and their ability to detect infections and provide infection intensity data. In the current study real-time PCR showed a higher sensitivity for the detection of intestinal helminths and protozoa especially in cases of mixed infections as well as more accurate determination of infection intensity compared to microscopy.

Helminthiasis: Hookworm Infection Remains a Public Health Problem in Dera District, South Gondar, Ethiopia

BACKGROUND

Intestinal parasitic infections are significant cause of morbidity and mortality in endemic countries. In Ethiopia, helminthiasis was the third leading cause of outpatient visits. Despite the health extension program was launched to address this problem, there is limited information on the burden of intestinal parasites after implementation of the program in our setting. Therefore, the aim of this study was to assess the intestinal helminthic infections among clients attending at Anbesame health center, South Gondar, Ethiopia.

METHODS

A cross sectional study was conducted at Anbesame health center from March to June 2015. A structured questionnaire was used to collect data from 464 study participants selected consecutively. Stool specimen collection, processing through formol-ether concentration technique and microscopic examination for presence of parasites were carried out. Data were entered, cleaned and analyzed using SPSS Version 20.

RESULTS

Among the total 464 study participants with median (±IQR) age of 25.0 (±21.75) years, 262 (56.5%) were females. Helminthic infection was found in 97 (20.9%) participants. Hookworm (68 [14.7%]) was the predominant parasite followed by S. mansoni (11 [2.4%]), E. vermicularis (9 [1.9%]) and S. stercoralis (5 [1.1%]). Patients with age group ≥15 years (AOR: 5.26; 95% CI: 2.05-13.46; P: 0.001) and walking barefoot (AOR: 2.20; 95% CI: 1.08-4.48; P: 0.031) were more vulnerable from the hookworm infections.

CONCLUSIONS

There was a high burden of hookworm infections in our setting. Hence, regular shoes wearing, considering all age groups in the albendazole deworming as mass treatment and environmental hygiene are important interventions to reduce the burden of such neglected tropical disease.

A survey for potentially zoonotic gastrointestinal parasites of dogs and pigs in Cambodia

There is little information available on parasites of zoonotic significance in Cambodia. In 2011, in an effort to obtain data on potentially zoonotic gastrointestinal parasites in domestic animals, 50 dogs and 30 pigs residing in 38 households located in Ang Svay Check village, Takeo province, Cambodia were examined for parasites from faecal samples. The samples were processed using the formalin-ethyl acetate concentration technique (FECT). Hookworms were the most common zoonotic parasite found in dogs (80.0%) followed by Echinostomes (18.0%). While, in pigs, Fasciolopsis buski was the most common zoonotic parasite (30.0%) followed by Ascaris suum (13.3%). This study provides baseline data on gastrointestinal parasites in dogs and pigs from Cambodia and underscores the importance of domestic animals as reservoir hosts for human parasites for Cambodian veterinary and public health agencies. Follow-up studies are required to further taxonomically characterize these dog and pig parasites and to determine their role in human parasites in this community.

[Survey of epidemic status of principal human parasites in Jiangxi Province in 2014]

OBJECTIVE

To understand and analyze the epidemic status of principal human parasites in Jiangxi Province, so as to provide the evidence for formulating The 13rd Five-Year Project of Parasites Control.

METHODS

A survey was performed according to the scheme of The 3rd National Survey of Principal Human Parasites as well as the specific situation of Jiangxi Province. The survey of the soil-transmitted nematodes and intestinal protozoa were performed based on the ecological regions and stratified by economic and geographic situation. The survey of Clonorchis sinensis was performed along with the soil-transmitted nematodes in rural, and was performed by the sample method of random cluster in cities and towns.

RESULTS

Totally 23 606 residents of 92 survey sites from 32 counties were surveyed, all of them were tested for the infection of soil-transmitted nematodes, in which 21,569 residents were tested for intestinal protozoa infection, and 1 486 children were tested for eggs of Enterobius vermicularis. Twenty kinds of intestinal parasites were found, with the total infection rate of 9.64%, and 4.296 millions of patients were reckoned in the whole Jiangxi Province. The infection rate of children of E. vermicularis was 13.73%. The infection rates of C. sinensis and intestinal protozoa were 0.58% and 1.42% respectively. The infection rate of Toxoplasma gondii was 7.50%.

CONCLUSION

In Jiangxi Province, the infection rates of soil-transmitted nematodes are decreasing but the infection rate of C. sinensis is increasing in local areas, and the control work of parasites still should be strengthened.

Human infections and co-infections with helminths in a rural population in Guichi, Anhui Province, China

Helminth infections are believed to be common in tropical and subtropical countries. A cross-sectional study was carried out in two villages located in Guichi District in Anhui Province, the People's Republic of China, where multiparasitism was investigated using parasitological tests. The data collected were fitted to Bayesian multi-level models to profile risk factors for helminth infections. The prevalence of Schistosoma (S.) japonicum, Ascaris (A.) lumbricoides and Trichuris (T.) trichiura were 0.43% (range: 0-0.87% at the village level), 2.28% (range: 1.69-2.88%), and 0.21% (range: 0-0.42%), respectively. No hookworm infection was found. With regard to multiparasitism, only a 33-year-old female was found to be co-infected with S. japonicum and A. lumbricoides. Multiparasitism was unexpectedly rare in the study area, which contrasts with results from other studies carried out elsewhere in the country. The long-term usage of albendazole for individuals serologically positive for schistosomiasis may be the main reason, but this needs to be confirmed by future studies.

[Effect of soil-transmitted helminthes control through mass deworming and latrine improvement]

OBJECTIVE

To evaluate the effect of soil-transmitted helminthes control through mass deworming and latrine improvement in rural areas.

METHODS

The data including mass deworming (1998-2000) and latrine improvement (2001-2010) were collected, summarized and analyzed in Danyang City. The infection rate of the soil-transmitted helminthes was monitored annually by using Kato-Katz method from 2001 to 2010. In addition, 2 villages with the improved latrines strategy and one village without the strategy were selected for hygienic evaluation.

RESULTS

Totally 1 130 000 person-times of mass deworming were carried out in Danyang City from 1998 to 2000, and the infection rate of soil transmitted helminthes of human was decreased from 40.82% to 1.10%. The infection rate (2.49%-4.81%) was bounced in the first five years (from 2001 to 2005) after mass deworming, while it gradually declined in the following five years (from 2006 to 2010) and maintained at a low level (0.07%-0.52%), and there was a significant difference between the average infection rates during the above two stages (χ2 = 353.83, P < 0.01). There was a negative correlation between the coverage rate of harmless latrine and the infection rate (r = -0.83, P < 0.01).

CONCLUSION

The mass deworming and latrine improvement are effective measures for the control of soil-trans-mitted helminthes infection in rural areas.

[Analysis of capability of examining helminthes: National technique competition of parasitic disease diagnosis in 2013]

OBJECTIVES

To understand the ability of worm detection of staff of centers for disease control and prevention (CDC) in China, so as to promote the ability construction.

METHODS

In each province, four competitors were selected from the institutions of parasitic diseases control to attend the National Technique Competition for Parasitic Disease Diagnosis and the results of competition were collected and analyzed.

RESULTS

The average scores of microscopic identification and slide preparation of all the 124 competitors were 27.3 and 7.6 respectively and the scores were increased significantly (t = 3.169, 5.009, both P < 0.05) compared to those in 2012. The average detection rate of helminthes was 62.7%, and it was increased significantly (χ2 = 28.630, P < 0.05) compared to that in 2012. The scores of competitors of different genders, ages, and profession titles were significantly different (t = 1.400, 2.080, F = 2.366-3.864, all P < 0.05). The scores of competitors of provinces with the control task of parasites were higher than those without any control task (t = 6.650, 4.630, both P < 0.01).

CONCLUSIONS

The competition has enhanced the ability of staff of CDCs, especially for the young staff. However, the ability of detection for soil transmitted helminth eggs should be intensified. Monitoring sites should be established in low endemic areas of parasites and provinces without the prevention and control task and the training for the professional staff should be strengthened.

New species of Prosotocus (Digenea; Pleurogenidae) and other helminths in Euphlyctis cyanophlyctis (Anura: Dicroglossidae) from Punjab, India

Prosotocus punjabensis sp. nov. (Digenea, Pleurogenidae) from the intestine of the water skipper, Euphlyctis cyanophlyctis (Anura, Dicroglossidae), from Punjab, India is described and illustrated. Prosotocus punjabensis sp. nov. is the 13th Oriental species assigned to the genus and is separated from its congeners based upon the morphology of the vitellaria and cecal terminations. In addition, E. cyanophlyctis was found to harbour three species of Nematoda, Aplectana macintoshii, Cosmocerca kalesari and an unidentified species assigned to Cosmocerca.