Intestinal Helminths Research Articles

An innate IL-25-ILC2-MDSC axis creates a cancer-permissive microenvironment for Apc mutation-driven intestinal tumorigenesis.

Interleukin-25 and group 2 innate lymphoid cells (ILC2s) defend the host against intestinal helminth infection, and are associated with inappropriate allergic reactions. IL-33-activated ILC2s were previously found to augment protective tissue-specific pancreatic cancer immunity. Here, we showed that intestinal IL-25-activated ILC2s created an innate cancer-permissive microenvironment. Colorectal cancer (CRC) patients with higher tumor IL25 expression had reduced survival, and increased IL-25R-expressing tumor-resident ILC2s and myeloid-derived suppressor cells (MDSCs) associated with impaired anti-tumor responses. Ablation of IL-25-signalling reduced tumors, virtually doubling life-expectancy in an Apc-mutation-driven model of spontaneous intestinal tumorigenesis. Mechanistically, IL-25 promoted intratumoral ILC2s, which sustained tumor-infiltrating MDSCs to suppress anti-tumor immunity. Therapeutic antibody-mediated blockade of IL-25-signalling decreased intratumoral ILC2s, MDSCs and adenoma/adenocarcinoma, while increasing anti-tumor adaptive T cell and IFNγ-mediated immunity. Thus, the roles of innate epithelium-derived cytokines IL-25 and IL-33, and ILC2s in cancer cannot be generalized. The pro-tumoral nature of the IL-25-ILC2 axis in CRC highlights this pathway as a novel therapeutic target against CRC.

Microbial regulation of intestinal motility provides resistance against helminth infection

Soil-transmitted helminths cause widespread disease, infecting ~1.5 billion people living within poverty-stricken regions of tropical and subtropical countries. As adult worms inhabit the intestine alongside bacterial communities, we determined whether the bacterial microbiota impacted on host resistance against intestinal helminth infection. We infected germ-free, antibiotic-treated and specific pathogen-free mice, with the intestinal helminth Heligmosomoides polygyrus bakeri. Mice harboured increased parasite numbers in the absence of a bacterial microbiota, despite mounting a robust helminth-induced type 2 immune response. Alterations to parasite behaviour could already be observed at early time points following infection, including more proximal distribution of infective larvae along the intestinal tract and increased migration in a Baermann assay. Mice lacking a complex bacterial microbiota exhibited reduced levels of intestinal acetylcholine, a major excitatory intestinal neurotransmitter that promotes intestinal transit by activating muscarinic receptors. Both intestinal motility and host resistance against larval infection were restored by treatment with the muscarinic agonist bethanechol. These data provide evidence that a complex bacterial microbiota provides the host with resistance against intestinal helminths via its ability to regulate intestinal motility.

Tissue-based IL-10 signalling in helminth infection limits IFNγ expression and promotes the intestinal Th2 response

Type 2 immunity is activated in response to both allergens and helminth infection. It can be detrimental or beneficial, and there is a pressing need to better understand its regulation. The immunosuppressive cytokine IL-10 is known as a T helper 2 (Th2) effector molecule, but it is currently unclear whether IL-10 dampens or promotes Th2 differentiation during infection. Here we show that helminth infection in mice elicits IL-10 expression in both the intestinal lamina propria and the draining mesenteric lymph node, with higher expression in the infected tissue. In vitro, exogenous IL-10 enhanced Th2 differentiation in isolated CD4+ T cells, increasing expression of GATA3 and production of IL-5 and IL-13. The ability of IL-10 to amplify the Th2 response coincided with its suppression of IFNγ expression and in vivo we found that, in intestinal helminth infection, IL-10 receptor expression was higher on Th1 cells in the small intestine than on Th2 cells in the same tissue, or on any Th cell in the draining lymph node. In vivo blockade of IL-10 signalling during helminth infection resulted in an expansion of IFNγ+ and Tbet+ Th1 cells in the small intestine and a coincident decrease in IL-13, IL-5 and GATA3 expression by intestinal T cells. These changes in Th2 cytokines correlated with reduced expression of type 2 effector molecules, such as RELMα, and increased parasite egg production. Together our data indicate that IL-10 signalling promotes Th2 differentiation during helminth infection at least in part by regulating competing Th1 cells in the infected tissue.

The IL-25-dependent tuft cell circuit driven by intestinal helminths requires macrophage migration inhibitory factor (MIF)

Macrophage migration inhibitory factor (MIF) is a key innate immune mediator with chemokine- and cytokine-like properties in the inflammatory pathway. While its actions on macrophages are well-studied, its effects on other cell types are less understood. Here we report that MIF is required for expansion of intestinal tuft cells during infection with the helminth Nippostrongylus brasiliensis. MIF-deficient mice show defective innate responses following infection, lacking intestinal epithelial tuft cell hyperplasia or upregulation of goblet cell RELMβ, and fail to expand eosinophil, type 2 innate lymphoid cell (ILC2) and macrophage (M2) populations. Similar effects were observed in MIF-sufficient wild-type mice given the MIF inhibitor 4-IPP. MIF had no direct effect on epithelial cells in organoid cultures, and MIF-deficient intestinal stem cells could generate tuft cells in vitro in the presence of type 2 cytokines. In vivo the lack of MIF could be fully compensated by administration of IL-25, restoring tuft cell differentiation and goblet cell expression of RELM-β, demonstrating its requirement upstream of the ILC2-tuft cell circuit. Both ILC2s and macrophages expressed the MIF receptor CXCR4, indicating that MIF may act as an essential co-factor on both cell types to activate responses to IL-25 in helminth infection. [Display omitted]

Serum cytokine profile of pregnant women with malaria, intestinal helminths and HIV infections in Ibadan, Nigeria.

Malaria, helminthiasis and HIV are widespread in developing countries taking a heavy toll on pregnant women. Due to similar environmental and human factors of transmission, they co-exist. The epidemiology and pathology of these diseases have been extensively studied but data on serum cytokine profile changes which is crucial in pregnancy is limited. The aim of this study was to evaluate the co-infections and their impact on peripheral blood cytokines. Blood and stool samples were collected from recruited 18-45-year-old pregnant women in different trimesters who were apparently healthy with no obvious complications in pregnancy. Pretested questionnaires were administered for personal and socio-demographic details. Malaria parasitemia in Giemsa-stained thick blood films was examined microscopically. Stool samples were screened for helminths using Kato-Katz method. Cytokine levels of TNF-α, IFN-γ, IL-1α, IL-2, IL-4, IL-6, IL-10, IL-12p70, IL-13 and IL-17 in 121 serum samples were determined using ELISA. Data were analysed using descriptive statistics and Mann-Whitney U test at α0.05. Relative to the single infections, there were significant reductions in IFN-γ and IL-13 in second and third trimesters respectively in those with Plasmodium and helminth co-infection. IFN-γ and IL-17 were elevated while IL-1α and IL-12p70 were reduced in co-infection of helminths and HIV. Co-infection of Plasmodium and HIV in second and third trimesters showed significant elevations in IL-1α, IL-10 and IL-17 while TNF-α, IL-4 and IL-12p70 were significantly reduced. HIV in pregnancy and its co-infection with Plasmodium resulted in significant distortions in the cytokine profile. However, helminth and its co-infection with Plasmodium or HIV produced less changes in the cytokine profile.

Helminths and their management in Swiss Army horses: differences between riding horses and pack horses evidence the need of improvement.

Intestinal helminth management in horses has both clinical and epidemiologic relevance, in additional association with anthelmintic resistance. The Swiss Army employs military owned riding horses and privately owned pack horses, which are brought together for service periods up to 12 weeks. We compared husbandry conditions and intestinal helminth management of both groups via questionnaire and analysed faecal samples of 53 riding horses and 130 pack horses using combined sedimentation/flotation, the McMaster method and larval cultures. Riding horses only had cyathostomin infections (prevalence: 60,4 %), while pack horses harboured cyathostomins (71,5 %), Parascaris sp. (6,9 %) and Strongylus vulgaris (1,5 %). Regression models combining faecal sample results with questionnaire data unveiled correlations of husbandry practices with parasite frequencies identifying risk and protective factors. Pasture management, hygiene and deworming practices were highly variable for pack horses, while for riding horses there was an overall concept. This included a selective deworming strategy with faecal egg counts (FECs) of strongyles prior to deworming, applying a threshold of 200 eggs per gram of faeces (epg). Anthelmintic treatments based on FECs, weekly faeces removal on pastures (pastures), the use of macrocyclic lactones and deworming horses regularly were identified as protective factors regarding the 200 epg threshold for strongyle eggs. Accordingly, the mean epg for strongyle eggs between the groups (111 and 539 in riding and pack horses, respectively) was significantly different (p < 0,001). Overall, intestinal helminth management in pack -horses showed room for improvement regarding pasture hygiene, the used anthelmintics and the frequency of deworming, from which all Swiss Army horses would benefit, as they share pastures during their -service, therefore entailing the risk of parasite transmission.

Choline metabolism promotes M2 macrophage polarization in intestinal infection with helminth Heligmosomoides polygyrus

Abstract Choline is an essential nutrient functioning as a precursor for membrane phospholipid. In previous studies, LPS polarization augmented both the expression of the choline transporter CTL1 and choline uptake, while specific inhibition of choline transport led to increased TNFα and IL-6. However, whether choline metabolism regulates M2 macrophage polarization or Th2 cytokine inflammation in vivo is unclear. In vitro, CTL1 and phospholipid synthesis was induced in IL-4 polarized M2 macrophages. To determine the function of choline metabolism in M2 polarization in vivo, mice were infected with Heligmosomoides polygyrus, intraperitoneally injected with choline kinase α inhibitor, RSM-932A or vehicle, and sacrificed at day 17 post-infection. RSM-932A treatment impaired weight gain and peritoneal exudate cell numbers in both naïve and infected mice. Within the peritoneal cavity of infected mice, macrophages and B-1 lymphocytes were depleted by RSM-932A treatment, while monocytes and neutrophils were increased. Flow cytometric and intestinal immunofluorescence staining revealed that RSM-932A treatment prevented M2 macrophage polarization in H.polygyrus-infected mice with a significant reduction in expression of PD-L2 and CD206, and conversely increased expression of CD86 and PD-L1. Additionally, RELMα protein in the serum and peritoneal fluid was downregulated by RSM-932A treatment. The impaired M2 polarization was associated with some loss in optimal immunity to H.polygyrus with increased parasite egg burden but no differences in intestinal worm count. This study indicates that choline metabolism is required for M2 macrophage polarization and an optimal immune response against intestinal helminth infection.

The prevalence and intensity of intestinal helminths among institutionalized children in three states of South-East Nigeria.

Intestinal helminthiasis is one of the most common and neglected diseases affecting all age groups, especially among school children. It is a disease condition of suboptimal environment and poor personal hygiene, and is more prevalent in children in institutionalized centers. This study was aimed to determine the prevalence, pattern, and intensity of intestinal helminthiasis among children in motherless babies' homes/orphanages and the relationship between the prevalence and demographic characteristics of the children. The outcome may be useful in strengthening these homes through advocacy to the appropriate authorities on general health promotion and awareness for the management of the homes. It was a descriptive cross-sectional study carried out over 7 months (March-September 2017) in three states of the South-East Nigeria. Prior to the studies ethical clearance and permissions from relevant bodies were obtained. A total of 198 children aged 3 months to 17 years were recruited using multi-stage sampling methods from the homes and orphanages in Anambra, Ebonyi, and Enugu states. Their stool samples were collected and analyzed for ova of intestinal helminths using ether concentration and Kato-Katz techniques.Frequency tables were designed for relevant variables while quantitative variables were summarized using median and interquartile range (IQR). The relationship between demographic factors and presence of intestinal helminths amongst study participants was tested using Chi-square test and Fisher's exact test (FET) where appropriate. All analyses were done at the 5% level of significance, and a P value <.05 was considered statistically significant. : Children aged 1-5 years constituting the highest proportion 110 (55.6%). The median age (IQR) of the participants was 2.5 years (3 months to 17 years). They comprised of 89 (44.9%) males and 109 (55.1%) females with a male: female ratio of 1:1.2. The overall prevalence of intestinal helminths among institutionalized children was 5/198 (2.5%). Ascaris lumbricoides only was seen in four out of five (80%) infested subjects while mixed infestation of A. lumbricoides and Trichuris trichiura was seen in one out of five (20%) subjects. All the infected subjects had light intensity of 100-300 EPG. It was noted that three out of five infested subjects were preschool children. However, the difference between the age groups and intestinal infestation was not statistically significant (P > 0.05). All the subjects with helminthic infection were females. Gender and location of motherless babies' homes/orphanages were not significantly associated with the presence of infestation (P > 0.05). This study showed that the prevalence and intensity of intestinal helminthiasis amongst the surveyed children in the South-Eastern Nigeria are 2.5% and more common among preschool aged children.

Convergent evolution of a parasite-encoded complement control protein-scaffold to mimic binding of mammalian TGF-β to its receptors, TβRI and TβRII

The mouse intestinal helminth Heligmosomoides polygyrus modulates host immune responses by secreting a transforming growth factor (TGF)-β mimic (TGM), to expand the population of Foxp3+ Tregs. TGM comprises five complement control protein (CCP)-like domains, designated D1-D5. Though lacking homology to TGF-β, TGM binds directly to the TGF-β receptors TβRI and TβRII and stimulates the differentiation of naïve T-cells into Tregs. However, the molecular determinants of binding are unclear. Here, we used surface plasmon resonance, isothermal calorimetry, NMR spectroscopy, and mutagenesis to investigate how TGM binds the TGF-β receptors. We demonstrate that binding is modular, with D1-D2 binding to TβRI and D3 binding to TβRII. D1-D2 and D3 were further shown to compete with TGF-β(TβRII)2 and TGF-β for binding to TβRI and TβRII, respectively. The solution structure of TGM-D3 revealed that TGM adopts a CCP-like fold but is also modified to allow the C-terminal strand to diverge, leading to an expansion of the domain and opening potential interaction surfaces. TGM-D3 also incorporates a long structurally ordered hypervariable loop, adding further potential interaction sites. Through NMR shift perturbations and binding studies of TGM-D3 and TβRII variants, TGM-D3 was shown to occupy the same site of TβRII as bound by TGF-β using both a novel interaction surface and the hypervariable loop. These results, together with the identification of other secreted CCP-like proteins with immunomodulatory activity in H. polygyrus, suggest that TGM is part of a larger family of evolutionarily plastic parasite effector molecules that mediate novel interactions with their host.

Common intestinal parasitic infections among patients living in Riyadh, Saudi Arabia: Prevalence and demographic associations (A cross-sectional retrospective study)

BackgroundThis study aimed to determine the prevalence and associated factors of intestinal parasitic infections (IPIs) among patients referred from different primary healthcare centers (PHC) in Riyadh, Kingdom of Saudi Arabia. Material & methodsA cross-sectional retrospective study conducted at Riyadh Regional Laboratory (RRL). All stool samples that are requested for intestinal parasite detection by physicians from PHCs across the Riyadh Region during year 2020 are referred to the RRL. The data recorded included age, sex, nationality, PHC location, and the stool analysis result with the type of parasite detected. ResultsThe data of 1148 patients were collected and statistically analyzed. IPIs were present in 296 (25.8%) patients, among whom 40 were infected with more than one parasite. The rate of infection with intestinal protozoa (95.4%) was higher than that with intestinal helminths (4.6%). Sixty (17.4%) infections were caused by pathogenic intestinal parasites, including pathogenic protozoa and helminths. The most common pathogenic protozoa were Entamoeba histolytica/dispar, which represented 9.3% of all IPIs and 72.7% of infections caused by pathogenic protozoa. Saudi nationals were the predominant population infected with pathogenic protozoa (44.0%). Ascaris lumbricoides was the most common helminth infection (56.3%) among patients. Nonpathogenic IPIs were detected at a higher rate (82.6%) than pathogenic IPIs (17.4%), with the predominant protozoa being Blastocystis hominis (61.0%). A higher rate of IPIs was observed in expatriates than in Saudi nationals (229 [33.6%] vs. 67 [14.3%], respectively) (P = 0.0000). ConclusionsAmong the 12 different nationalities in our study cohort, the prevalence was the lowest in Saudi nationals (14.3%). The prevalence of B. hominis was high in all areas and nationalities, affecting all age groups among the patients referred for stool analysis. The implementation of preventive measures and awareness programs regarding sanitation and personal hygiene are needed.

Intestinal Helminth infections and associated risk factors in dogs of Dhaka City, Bangladesh

This study was conducted to determine the prevalence and related risk factors for intestinal helminth infections in companion and stray dogs from Dhaka, Bangladesh. In total 310 fecal samples were collected from companion dogs (206 samples) and stray dogs (104 samples) from Dhaka south city corporation (DSCC) and Dhaka North city corporation (DNCC) areas. Salt flotation and formol ether concentration techniques were used to process the fecal samples. The prevalence of intestinal helminth infections in stray and companion dogs in DSCC was 48.98% and 18.02%, respectively, while in DNCC, it was 7.27% and 15.79%. Ancylostomatids showed the maximum prevalence (18.37%) followed by Toxocara canis (14.28%). Intestinal parasitic infections were more prevalent among female companion dogs (17.24%) than males (16.89%). Dogs of pure or mixed breed were prone to parasitic infections (29.09%). Outdoor access (P=0.000) and irregular deworming (P=0.000) were potential risk factors for intestinal helminth infections in companion dogs. Helminth infections in dogs could be a major public health concern. Proper sanitation measures especially in DSCC areas are necessary to check this alarming issue. Bangladesh J. Zool. 49 (3): 411-421, 2021

Reconstructing the history of helminth prevalence in the UK.

Intestinal helminth parasites (worms) have afflicted humans throughout history and their eggs are readily detected in archaeological deposits including at locations where intestinal parasites are no longer considered endemic (e.g. the UK). Parasites provide valuable archaeological insights into historical health, sanitation, hygiene, dietary and culinary practices, as well as other factors. Differences in the prevalence of helminths over time may help us understand factors that affected the rate of infection of these parasites in past populations. While communal deposits often contain relatively high numbers of parasite eggs, these cannot be used to calculate prevalence rates, which are a key epidemiological measure of infection. The prevalence of intestinal helminths was investigated through time in England, based on analysis of 464 human burials from 17 sites, dating from the Prehistoric to Industrial periods. Eggs from two faecal-oral transmitted nematodes (Ascaris sp. and Trichuris sp.) and the food-derived cestodes (Taenia spp. and Diphyllobothrium latum syn Dibothriocephalus latus) were identified, although only Ascaris was detected at a high frequency. The changing prevalence of nematode infections can be attributed to changes in effective sanitation or other factors that affect these faecal-oral transmitted parasites and the presence of cestode infections reflect dietary and culinary preferences. These results indicate that the impact of helminth infections on past populations varied over time, and that some locations witnessed a dramatic reduction in parasite prevalence during the industrial era (18th-19th century), whereas other locations continued to experience high prevalence levels. The factors underlying these reductions and the variation in prevalence provide a key historical context for modern anthelmintic programs.

Prevalence of Intestinal Helminths among Cancer Patients Who Are under Chemotherapy at the University of Gondar Comprehensive Specialized Hospital Oncology Clinic, Northwest Ethiopia.

Background In developing countries, environmental and personal hygiene is playing a great role in the increasing of intestinal helminth infection. In countries with limited resources and poor hygiene practices, there is a substantial overlap of intestinal helminthic and chronic infections like HIV, TB, and cancer. Intestinal helminths like Ascaris lumbricoides, Trichuris trichiura, and hookworm cause malnutrition and induce a type-2 immune response that could worsen the severity and clinical outcomes of patients with cancer. Our aim was to determine the prevalence of intestinal helminths among cancer patients who are under chemotherapy. Methodology. A prospective cross-sectional study was conducted in volunteer cancer patients. Clinical information were collected from study participants using a structured questioner. Stool sample was collected for parasitological examination. Formol-ether concentration technique was done, and then, two microscopic slides were prepared. Examination was done by two laboratory technicians for the detection of helminths. SPSS version 22 was used for data analysis, and simple descriptive statistical analysis was done for data presentation. Result The total study participants were 41, of these 31 (75.6%) were females and 10 (24.4%) were male. Breast cancer and colonic cancer were the highest proportion with the others, 43.9% and 17.1%, respectively. The prevalence of intestinal parasites were 7/41 (17%). Hookworm 3/41(7.3%), Ascaris lumbricoides 3/41(7.3%), and Hymenolepis nana 1/41(2.4%) are the isolated parasite. Conclusions and Recommendations. The prevalence of intestinal helminths in cancer is lower than HIV and DM in the study area. However, the prevalence in these cancer patients is still high and needs deworming and health education for the better management of these cancer patients.

HELMINTHOFAUNA OF HORSES IN RYAZAN REGION

The high susceptibility of horses to invasive diseases caused by the intestinal helminthofauna, regardless of age, physiological state of the livestock of horse breeding farms, is still the object of research. The damage caused by helminths is a decrease in productivity and efficiency, weakening the immunity of horses and, with severe invasion, can lead to blockage of the intestines, colic and death of animals. Only timely detection of parasites and subsequent treatment, prevention of invasive diseases can prevent economic losses. The importance of studying the climatic and geographical distribution of these parasitic organisms becomes obvious. This paper discusses the presence of horse helminths as a phenomenon in the Ryazan Region. 26 fecal samples from horses aged 5–10 years were examined using the microscopy method. Samples of fresh feces were taken from individual stalls twice: on November 16, 2021 and on December 2, 2021. Identification of intestinal helminths was conducted by the Fulleborn method (with a saturated saline solution) followed by examination of drops under a microscope with a magnification of 400. As a result of the studies, eggs of Strongylus equinus, Parascaris equorum, as well as sexually mature representatives of Parascaris equorum after livestock deworming were found. Antiparasitic measures were selected taking into account the biology of the pathogen.

ANTIPARASITIC GRAIN-FODDER GRANULES FOR HELMINTHIASES OF HORSES

Helminthiastic infestations are widespread in horse-breeding farms of the Altai Mountains. The specifics of the industry involve the use of therapeutic agents that have not only a wide range of antiparasitic activity, but also manufacturability in application. The purpose of this research is to develop a new prescription of antiparasitic feed granules (AFG) based on grain-fodder raw materials with aversectin C and albendazole and to assess their effectiveness against intestinal helminthiasis of horses. The efficacy study was conducted on the principle of "critical test", 2 experimental groups of horses of 20 and 16 heads of the New Altai breed were formed. Before giving the drug and after 15 days, coproovoscopic studies of horse feces for the presence of eggs of intestinal helminths by the flotation method were carried out. AFGs were fed to horses once, in a group way from feeders at the rate of 2.5 g per kg of animal weight (aversectin – 0.2 mg, albendazole 5 mg/ kg b/w). Animals ate antiparasitic granules well, after taking the drugs there was no toxic effect on the body of horses. Feeding to horses with AFG provided high efficacy of the drug in strongylatosis of the gastrointestinal tract, parascariasis and anoplocephalidosis of horses (90.1–100%).

Circulating IL-6, IL-10, and TNF-alpha and IL-10/IL-6 and IL-10/TNF-alpha ratio profiles of polyparasitized individuals in rural and urban areas of gabon

Malaria, blood-borne filarial worms and intestinal parasites are all endemic in Gabon. This geographical co-distribution leads to polyparasitism and, consequently, the possibility of immune-mediated interactions among different parasite species. Intestinal protozoa and helminths could modulate antimalarial immunity, for example, thereby potentially increasing or reducing susceptibility to malaria. The aim of the study was to compare the cytokine levels and cytokine ratios according to parasitic profiles of the population to determine the potential role of co-endemic parasites in the malaria susceptibility of populations. Blood and stool samples were collected during cross-sectional surveys in five provinces of Gabon. Parasitological diagnosis was performed to detect plasmodial parasites, Loa loa, Mansonella perstans, intestinal helminths (STHs) and protozoan parasites. Nested PCR was used to detect submicroscopic plasmodial infection in individuals with negative blood smears. A cytometric bead array was used to quantify interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α in the plasma of subjects with different parasitological profiles. Median IL-6 and IL-10 levels and the median IL-10/TNF-α ratio were all significantly higher among individuals with Plasmodium (P.) falciparum infection than among other participants (p<0.0001). The median TNF-α level and IL-10/IL-6 ratio were higher in subjects with STHs (p = 0.09) and P. falciparum-intestinal protozoa co-infection (p = 0.04), respectively. IL-6 (r = -0.37; P<0.01) and IL-10 (r = -0.37; P<0.01) levels and the IL-10/TNF-α ratio (r = -0.36; P<0.01) correlated negatively with age. Among children under five years old, the IL-10/TNF-α and IL-10/IL-6 ratios were higher in those with intestinal protozoan infections than in uninfected children. The IL-10/TNF-α ratio was also higher in children aged 5-15 years and in adults harbouring blood-borne filariae than in their control counterparts, whereas the IL-10/IL-6 ratio was lower in those aged 5-15 years with filariae and intestinal parasites but higher in adults with intestinal parasitic infections. Asymptomatic malaria is associated with a strong polarization towards a regulatory immune response, presenting high circulating levels of IL-10. P. falciparum/intestinal protozoa co-infections were associated with an enhanced IL-10 response. Immunity against malaria could differ according to age and carriage of other parasites. Helminths and intestinal protozoa can play a role in the high susceptibility to malaria currently observed in some areas of Gabon, but further investigations are necessary.

Effects of Schyzocotyle acheilognathi (Yamaguti, 1934) infection on the intestinal microbiota, growth and immune reactions of grass carp (Ctenopharyngodon idella).

Our understanding of interactions among intestinal helminths, gut microbiota and host is still in its infancy in fish. In this study, the effects of Schyzocotyle acheilognathi infection on the intestinal microbiota, growth and immune reactions of grass carp were explored under laboratory conditions. 16S rDNA amplification sequencing results showed that S. acheilognathi infection altered the composition of intestinal microbiota only at the genus level, with a significant increase in the relative abundance of Turicibacter and Ruminococcus (P < 0.05) and a significant decrease in the relative abundance of Gordonia, Mycobacterium and Pseudocanthomonas (P < 0.05). Schyzocotyle acheilognathi infection had no significant effect (P > 0.05) on the alpha diversity indices (including Chao1, ACE, Shannon, Simpson index) of intestinal microbiota in grass carp, but PERMANOVA analysis showed that microbial structure significantly (P < 0.01) differed between hindgut and foregut. PICRUST prediction showed that some metabolism-related pathways were significantly changed after S. acheilognathi infection. The relative abundance of Turicibacter was positively correlated with the fresh weight of tapeworm (foregut: r = 0.48, P = 0.044; hindgut: r = 0.63, P = 0.005). There was no significant difference in the body condition of grass carp between the S. acheilognathi infected group and the uninfected group (P > 0.05). Intestinal tissue section with HE staining showed that S. acheilognathi infection severely damaged the intestinal villi, causing serious degeneration, necrosis and shedding of intestinal epithelial cells. The real-time fluorescent quantitative PCR results showed that S. acheilognathi infection upregulated the mRNA expression of the immune-related genes: Gal1−L2, TGF−β1 and IgM.

Cross-Sectional Study on Assessment of Frequency of Intestinal Helminth Infections and Its Related Risk Factors among School Children from Adola Town, Ethiopia.

The three main intestinal helminth infections (IHIs), ascariasis, trichuriasis, and hookworm, are common clinical disorders worldwide. These IHIs are more prevalent in tropics and subtropical countries especially in developing countries like sub-Saharan Africa responsible for morbidity, mortality, and physical as well as intellectual growth retardation in children. In Ethiopia, the burden of IHIs appears in all ages mainly due to factors like lack of education, low socio-economic status, and inadequate supply of drugs and proper awareness. The present study was carried out to access the prevalence of intestinal helminth infections and associated risk factors among school children in Adola town from Guji Zone, Oromia, Ethiopia, from August 2019 to December 2019. 404 stool samples were collected in a clean, dry, screw-capped, and wide-mouthed plastic container, fixed with 10% formal-saline solution, and transported to the Adola Hospital laboratory for further microscopic analysis by wet mount following formal ether concentration technique. Data were analyzed using SPSS version 20 by binary logistic regression model using odd ratio with 95% CI. The overall prevalence of IHIs among school children was found to be 33.91% (137/404). Rate of double infection was noted to be 2.72% (11/404). Most dominant species was Ascaris lumbricoides (8.9%) followed by Hymenolepis nana (7.7%), Taenia saginata (5.4%), hookworm (4.7%), Trichuris trichiura (2.5%), Schistosoma mansoni (2.2%), Enterobius vermicularis (1.7%), and Strongyloides stercoralis (0.7%), respectively. Highest prevalence was observed in male students (39.6%) compared to female students (28.8%) (P < 0.05). The prevalence of IHIs among school children in the age group of 6-10, 11-15, 16-20, and above 20 was 49.6%, 35.8%, 10.9%, and 3.6%, respectively (P < 0.05). IHI was significantly associated with some of the risk factors such as gender, educational level of students', toilet usage habit, habit of hand washing, hand washing habit before feeding and after defecation, purpose of hand washing, and awareness to intestinal helminths (P < 0.05). In the study area, the prevalence of IHIs is moderately high and represents a public health problem in the school children. Therefore, all stakeholders should pay attention to raise awareness about health education programs such as proper personal hygiene, environmental sanitation, improving the quality of drinking water, and treatment to reduce the consequences of intestinal helminths.

Prevalence of Intestinal Parasites and Their Transmission Risk Factors among Inmates of Naivasha and Kisii Prisons in Kenya

Parasites live off a host to survive where they grow, reproduce and invade organ systems therefore causing parasitic infections. Among the ten most common parasitic infections according to world health organization are hookworm, ascariasis, amoebiasis and trichuriasis. Parasitic infections in endemic countries shorten lives and impose a lifelong burden on the potential for advancement. Limited studies have been carried out to establish the prevalence of intestinal parasites among neglected and institutionalized groups of the population such as prison inmates which justified the need to establish the prevalence of intestinal parasitic infections (IPIs) among inmates of Kisii and Naivasha prisons in Kenya. A cross-sectional study was used. Four hundred inmates after sampling, provided stool samples for analysis. Formal-ether concentration techniques was used for identification of helminths eggs and cysts of protozoa while direct wet mount using saline and iodine was used for microscopic examination of loose stool for identification of trophozoites of protozoa. Data on the predisposing factors were collected using structured questionnaire and focus group discussion. Chi Square test was used to determine the association between age groups and sex while odds ratio was used to determine the association of personal hygiene and infection by intestinal parasites. The prevalence rate of intestinal parasites was 84(20.84%) with Kisii prison having a prevalence of 37(20.04%) while Naivasha prison having 47(21.56%). Intestinal protozoa infections were higher 50(12.4%) than helminthes 28(10.4%). Intestinal protozoa identified were Entamoeba histolytica 30(7.4%) and Giardia lamblia 20(4.9%) while the intestinal helminthes identified were Ascaris lumbricoides 22(5.5%), Strongyloides stercolaris 2(0.5%) and hookworms 4(1.0%). Chi square test showed that significantly more females were infected than males (χ² = 12.53, P=0.016, df = 2) as well as inmates of 18-27 years in both prisons (χ² = 9.36, P=0.007, df = 28). Correlation coefficient indicated that the infections increased with lack of footwear (OR 2.68, Cl 0.94-3.41), failures to hand wash before meals (OR 2.88, Cl 0.93-3.36) and after toilet use (OR 2.19, Cl 1.02-4.44). Provision of health education and personal hygiene and sanitation, more pit latrines with enough water points for hand washing as well as sufficient footwear is recommended to reduce the IPIs in the prisons. This can be facilitated by the officers-in-charge in collaboration with the Ministry of health.

Zoonotic intestinal helminthes diagnosed in a 6-year period (2015-2020) in privately owned dogs of sub-urban and urban areas of Italy.

Intestinal helminthes of dogs have a relevant role for health and welfare of canine populations and many of them are zoonotic. Thus, a constant surveillance is pivotal to safeguard companion dogs and human health. Data from faecal examinations of pet dogs obtained in the last six years during the routine activity of the laboratory of Parasitology and Parasitic diseases of the University Teaching Veterinary Hospital of the University of Teramo, Italy, are here reported. From 2015 to 2020 a total of 1083 individual faecal samples from privately owned dogs were examined using conventional copro-microscopic techniques. Endoparasite elements were found in 278 (25.7%) dogs, and among them, eggs of intestinal zoonotic helminthes were detected in 184 (17%) samples. The most common zoonotic parasites were Toxocara canis and hookworms (8.9% positivity rate for both). Most dogs (88%) were positive for a single zoonotic parasite while 12% of the positive animals harbored two or more zoonotic helminthes. A statistical analysis showed a significant association between dogs with less than one year of age and positivity to at least one intestinal zoonotic helminth, and that infections by T. canis are significantly more prevalent in dogs under one year of age. Despite being well known in canine clinical practice, these results indicate that zoonotic helminthes are still frequent in owned dogs. Thus, increased awareness of veterinary practitioners and pet owners is necessary to implement current diagnostic and control strategies to minimize the risk of zoonotic transmission of intestinal helminthes.