Intestinal Helminth Infections Research Articles

Survey on Intestinal Helminthic Infection Status of Students in Two Counties, Hadong-gun and Goseong-gun, Korea.

This study was conducted to investigate the prevalence of intestinal parasites among students from Goseong-gun, Gangwon-do and Hadong-gun, Gyeongsangnam-do as typical low and high endemic counties. From May to July 2017, a total of 2,033 fecal samples were collected at 27 elementary, 10 junior high, and 8 high schools from 2 counties and examined by the Kato-Katz technique for egg-positive surveys (Collection rate: 37.02% [2,033/5,492]). Of the participants examined, 13 (0.64%) were found to harbor eggs of 3 parasitic species, Trichuris trichiura, Clonorchis sinensis and Metagonimus yokogawai. Based on the regional distribution, the egg-positive rate in Goseong-gun was 0% (0/550) and that in Hadong-gun was 0.88% (13/1,483). The positive rates for C. sinensis, M. yokogawai, and T. trichiura in Hadong-gun were 0.20% (3/1,483), 0.61% (9/1,483), and 0.07% (1/1,483), respectively. The present survey showed that the prevalence of parasitic infection among students is currently very low even in remote, previously endemic areas, and the present status of parasitic diseases can be summarized as some transmission of fish/food-borne trematodes. Thus, it is necessary to carefully, continuously monitor the trematode infection status, particularly of C. sinensis and M. yokogawai.

Chronic lead intoxication decreases intestinal helminth species richness and infection intensity in mallards (Anas platyrhynchos)

Lead (Pb) pollution of aquatic habitats is a known threat to vertebrate health. Depending on Pb dosage, resulting symptoms can be chronic (sublethal) or acute (lethal). While acute exposure results in death of the animal, chronic sublethal exposure can also have consequences, reproduction, antioxidant defense and immunity being the most affected traits. While a great deal is known about Pb intoxication on avian health, relatively little is known about how intoxication impacts parasites dependent on their avian hosts. The effect of Pb on intestinal helminth species richness and infection intensity was investigated in mallards (Anas platyrhynchos, n = 100) from German waters. Coracoid bones were used to measure chronic Pb exposure. Intestinal helminths were characterized morphologically. Molecular approaches were also applied to identify poorly morphologically preserved parasites to obtain sequence data (cox1 gene) for species identification and future parasitological studies. Parasite species richness and infection intensity was found to be significantly lower in birds with higher chronic Pb levels suggesting both host and parasites respond to Pb exposure. Altered immune modulation in the avian host may be the underlying mechanisms of Pb triggered decrease of parasites. However, it also likely reflects differences in the susceptibility of different helminths to Pb. Cestode and acanthocephala species richness were particularly impacted by Pb exposure. We conclude that, Pb intoxication may both negatively impact avian host and parasite diversity in aquatic habitats.

Interleukin-9 promotes early mast cell-mediated expulsion of Strongyloides ratti but is dispensable for generation of protective memory

IL-9 is a cytokine with pleiotropic function that mediates allergic inflammation and immunity to intestinal helminth parasites. Accumulating evidence suggests that IL-9 acts via both, initiation and regulation of adaptive immune responses and direct activation of intestinal effector pathways. Here we use IL-9 receptor deficient mice on BALB/c and C57BL/6 genetic background to dissect effector and regulatory functions of IL-9 during infection with the parasitic nematode Strongyloides ratti. IL-9 receptor-deficient mice displayed increased intestinal parasite burden and prolonged infection irrespective of the genetic background of the mice. Increased parasite burden was correlated to a reciprocally reduced early degranulation of mucosal mast cells, reduced intestinal IL-13 expression and caused by IL-9 receptor deficiency on hematopoietic cells. We observed additional significant changes in the adaptive immune response to S. ratti infection in the absence of the IL-9 receptor that depended on the mouse strain. However, the generation of protective memory to a second infection was intact in IL-9 receptor-deficient mice, irrespective of the genetic background. In summary, our results support a central role for IL-9 as an early mast cell activating effector cytokine during intestinal helminth infection while non-redundant functions in the initiation and amplification of adaptive immune responses were not apparent.

Gastrointestinal Parasites of Sarotherodon melanotheron(Ruppel, 1852) Histopathological Alterations and Organochlorine Pesticides Pollution from Lagos, Lagoon, Nigeria.

This study investigates the prevalence and intensity of intestinal parasites and determines the combined impact of organochlorine pesticides and parasites on the total health of the fish in Lagos lagoon. Twelve congeners of organochloride pesticides (OCPs) were analyzed in water, sediment, fish and parasites using mass chromatograph coupled with an electron detector. The prevalence of intestinal helminth infection in Sarotheron melanotheron was 20.83%. Twenty-five individuals were infected with parasitic cestode Wenyonia sp (20.83%, Chi-Square, X² = 11.2, p<0.05), out of which 18 (15.00%) were males and 7 (5.83%) were females. The intestinal parasites found in S.melanotheron were cestode; Wenyonia sp, protozoa; Myxobolus sp. Coccidian spores, Myxosoma sp, and Hexamita sp. Five congeners were detected in the water, sediment, fish and parasites. Some protozoa parasites of Sarotherodon melanotheron have shown qualities of bioindicators from the study. Myxosoma sp showed positive correlation (r = 0.315, p<0.05) with DDT and heptachlor (r = 0.301, p<0.05) but its correlation coefficient was not significant for endosulfan 1, aldrin and total OCPs. None of the intestinal helminth parasite infection correlates significantly with any of the OCPs congeners in the lagoon. Iddo station had the highest parasite prevalence and concentrations of DDT, Aldrin, Dieldrin, and Heptachlor in the water and sediment and the highest GAI, showing high frequencies of several inflammations, and tissue necrosis as a result of greater multi-stress pressure.

Prevalence of Intestinal Helminthic Infections in Pregnant Women Attending Antenatal Clinic in Abeokuta, Nigeria

Intestinal infections during pregnancies are recorded with common factors which include prenatal mortality, poor nutritional status, impaired growth, low birth weight, anaemia and disease burden. It is one of the major public health problems in developing nations.&#x0D; This survey was carried out with 100 pregnant women attending Oba Ademola II Maternity Hospital, Ijemo, Abeokuta, within six months to determine the infection prevalence, intensity, risk factors and packed cell volume (PCV) correlation. Determination of helminth was done by formo-ether sedimentation technique. Structured questionnaire was applied and analyzed using Analysis of variance (ANOVA).&#x0D; Results revealed the prevalence of Hookworm to be 18%, while that of Ascaris was 50%. Comparison of age between 18-45 years old and level of education was also taken into consideration.&#x0D; Personal hygiene was significantly associated with reduced likelihood of infection. From this study, it is evident that helminthic infections were prevalent among pregnant women. It is therefore recommended that antenatal clinics should incorporate routine stool examination for pregnant women to detect parasitic worms and refer positive cases for medical treatment and routine deworming of all pregnant women after the first trimester should also be encouraged.

Prevalence of helminthic infection among primary school children in some selected primary schools in municipal local government area, Kano state, Nigeria

The research was conducted to study the prevalence of helminthic infection among primary school children in some selected primary schools in municipal local government area, Kano state. A total of 100 hundred school children between the ages group of 6-12 years old were examined for intestinal helminth infections using direct wet method and formol-ether concentration technique. The samples were collected from both sexes and were processed. Of the 100 pupils examined, 72.0% were infected with one or a combination of the worms with Ascaris having the highest prevalence rate (31.0%) followed by hookworm (19.0%), Schistosoma (8.0%), Enterobius (8.0%), Strongyloides (6.0%) had the least rate of infection as shown in table 3. The prevalence of infection of helminth parasite among schools ranged between (A) 17(23.62%), (B) 14(19.4%), (C) 12(16.67%), (D) 15(20.83%), and (E) 14(19.44%) with no significant difference in the prevalence of infection between schools (p&gt;0.05). Table 1 shows that out of 100 pupils examined, 40(40.0%) males and 60(60.0%) females respectively, of these 27(67.5%) males and 45(75.0) females were infected, the difference not significant (p&gt;0.05). Of the 72 infected subject 17(23.6%) have multiple infection with 11(15.3%) and 6(8.4%) having double and triple infections respectively. Ascaris occur mostly with other helminth, Ascaris lumbricoides+ hookworm and Ascaris +enterobius vermicularis+ hookworm mostly were more common occurring combinations.

Prevalence and factors associated with intestinal protozoan and helminthic infections among certified food handlers in Eldoret town, Uasin Gishu county in Kenya

Background Food and water remain a major source of most these intestinal parasites with food handlers acting as reservoirs and transmission agents Objective This study aimed at determining the prevalence and factors associated with intestinal parasitic infections among certified food handlers in Eldoret Town Methods The study area was Eldoret town in Uasin Gishu County Data collection took place between the month of May and June The cross sectional study enrolled certified food handlers with valid medical certificates in various food establishments in Eldoret town Results The overall prevalence of intestinal parasitic infection among the certified food handlers was E histolytica n was the most prevalent intestinal parasite The prevalence of intestinal parasites differed significantly by food handlers rsquo age groups per capita monthly income type of organic waste receptacle inside the food premise and hand washing habit after visiting a toilet latrine p lt Food handlers rsquo failure to wash their hands after visiting a toilet latrine was a risk factor associated with intestinal parasitic infections OR p Conclusion The high prevalence of intestinal parasitic infections reported among the certified food handlers in Eldoret is a clear indication of poor food handling practices in the town

Epidemiology of soil transmitted Helminth infections in the middle-belt of Ghana, Africa

BackgroundHelminths are among the most widespread infectious agents prevalent in tropical and sub-tropical regions of the developing world defined by inadequate sanitation, poverty and unsafe water sources. This study was carried out to describe the distribution of helminth and malaria parasite infections in the middle-belt of Ghana in sub-Saharan Africa where disease burden, including anaemia is rife and helminths are perceived to be significant contributors of the burden. MethodsA cross-sectional survey involving 1826 residents located in the middle belt of Ghana where no or very little previous community-based helminth work had been carried out. The participants randomly recruited at household level provided biological samples collected over a 12-month period following a rigorous consenting process and these were analysed to describe the different types and seasonal distribution of helminths. FindingsOverall, 19.3% intestinal helminth infection prevalence was documented. Also based on parasites targeted for elimination, 12.1% Hookworm, 4.0% Hymenolepis nana/Hymenolepis dimunita, 1.5% Ascaris lumbricoides, 1.5% Taenia species, 0.9% Strongyloides stercoralis and 0.8% Trichuris trichiura, with about 1.0% polyphelminthiasis were recorded in the survey. About 55.4% and 44.4% of the participants had heavy hookworm and Trichuris infections respectively. Most of the Ascariasis (83.3%) infections were light in intensity. Hookworm infection was identified with significant odds considering decreasing age (OR = 2.09, p = 0.03), inappropriate footwear use (OR = 1.88, p = 0.021), malaria parasite co-infection (OR = 1.62, p = 0.018), not scrubbing nails during hand washing (OR = 0.68, p = 0.048), source of drinking water (OR = 2.51, p = 0.027) and religion (OR = 4.36, p = 0.002). ConclusionsHookworm infection was significantly higher in younger age groups and among those who did not have safe drinking water. Proper sanitation, protective footwear, religion and good personal hygiene practices were found to influence helminth and hookworm prevalence in the area. Malaria parasite coinfection with helminths, especially hookworm infections increased 2-fold.

Associations of intestinal helminth infections with health parameters of spring-migrating female lesser scaup (Aythya affinis) in the upper Midwest, USA.

Thousands of lesser scaup (Aythya affinis) die during spring and fall migrations through the upper Midwest, USA, from infections with Cyathocotyle bushiensis and Sphaeridiotrema spp. (Class: Trematoda) after ingesting infected intermediate hosts, such as non-native faucet snails (Bithynia tentaculata). The lesser scaup is a species of conservation concern and is highly susceptible to these infections. We collected female lesser scaup from spring migratory stopover locations throughout Illinois and Wisconsin and assessed biochemical and morphological indicators of health in relation to intestinal helminth loads. Helminth species diversity, total trematode abundance, and the infection intensities of the trematodes C. bushiensis and Sphaeridiotrema spp. were associated with percent body fat, blood metabolites, hematological measures, and an index of foraging habitat quality. Helminth diversity was negatively associated with percent body fat, albumin concentrations, and monocytes, whereas glucose concentrations displayed a slight, positive association. Total trematode abundance was negatively associated with blood concentrations of non-esterified fatty acids and albumin. Infections of C. bushiensis were positively related to basophil levels, whereas Sphaeridiotrema spp. infection intensity was negatively associated with packed cell volume and foraging habitat quality. Thus, commonly measured health metrics may indicate intestinal parasite infections and help waterfowl managers understand overall habitat quality. Intestinal parasitic loads offer another plausible mechanism underlying the spring condition hypothesis.

Low prevalence of intestinal helminth infections among primary school children in Tengrela, northern Cô€te d’Ivoire

Intestinal helminthiasis are endemic in Côte d’Ivoire and represent a real health problem because of health burden particularly in children. In order to eliminate the disease as a public health problem the Ministry of Health and Public Hygiene has been implementing mass drug administration in primary schools since 2012. Five years later, a cross-sectional study (October 2016 to January 2017) was conducted among 515 primary school children aged 4-15 in the department of Tengrela to estimate the prevalence of intestinal helminthiasis and to identify the species causing these parasite infections in order to develop preventive measure. Single stool samples were analysed using the direct smear in saline solution and Kato-Katz techniques. The overall intestinal helminths prevalence was 3.3% (CI 95% = 2.0-5.1). Hookworms (1.0%) and, Trichiuris trichiura (1.0%) were the predominante parasites followed by Ascaris lumbricoides (0.8%), and Hymenolepis nana (0.6%). No polyparasitism case was noted. Walking bare feet was associated to the occurrence of the parasitism (p=0.015). However, gender, age, the faecal disposal system and the mode of drinking water supply were not linked to the intestinal parasitism (p&gt;0.05). The intestinal helminthiasis among primary school children in Tengrela are dominated by the hookworm Trichuris trichiura and Ascaris lumbricoides infections. It is important to provide health education for wearing shoes to avoid infection of skin-penetrators. Interventions aimed to improve sanitation access should be highlighted in the recommendations for the control of intestinal helminthiasis.Keywords: Intestinal helminthiasis; school children; Tengrela; Côte d’Ivoire

Stratified sampling survey of major human parasitic diseases in Henan province

Objective: To understand the prevalence of major human parasitic diseases and related factors in Henan province. Methods: This stratified sampling survey was carried out according to the requirement of national survey protocol of major human parasitic diseases, 2014-2015. The prevalence of soil-transmitted helminths infection, taeniasis and intestinal protozoiasis were surveyed in 104 sites selected from 35 counties (districts) and the prevalence of clonorchiasis was surveyed in 62 sites selected from 37 townships. In each survey spot, 250 persons were surveyed. A total of 26 866 persons and 15 893 persons were surveyed. Modified Kato-Katz thick smear was used to detect the eggs of intestinal helminthes. Tube fecal culture was used to identify the species of hookworm. The Enterobius eggs were detected in children aged 3 to 6 years by using adhesive tape. The cyst and trophozoite of intestinal protozoa were examined with physiological saline direct smear method and iodine stain method. Results: The overall infestation rate of intestinal parasites was2.02% in Henan, and the worm infection rate was higher than protozoa infection rate. Fourteen kinds of intestinal parasites were found, including nematode (5 species), trematode (2 species), and protozoan (7 species). The infection rate of Enterobius vermicularis was highest, and Qinba Mountain ecological area had the highest infestation rate of intestinal parasites in 4 ecological areas of Henan. There was no significant difference in intestinal parasite infection rate between males and females (χ(2)=3.630, P=0.057), and the differences in intestinal parasite infection rate among different age groups had significance (χ(2)=124.783, P=0.000 1). The infection rate reached the peak in age group ≤9 years and the major parasite was Enterobius vermicularis. Furthermore the overall human infection rate of parasite showed a downward trend with the increase of educational level of the people (χ(2)=70.969, P=0.000 1), the differences had significance (χ(2)=120.118, P=0.000 1). For different populations, the infection rate of intestinal parasites was highest among preschool children. The infection of intestinal helminth was mainly mild, only 2 severe cases were detected. The infection rate of Clonorchis sinensis in urban residents was only 0.006%. Logistic regression analysis showed that being preschool children (χ(2)=15.765, P=0.000 1) and drinking well water (χ(2)=45.589, P=0.000 1) were the risk factors for intestinal parasite infection, and annual income per capita of farmers was the protective factor against intestinal parasite infection. The infection rates of protozoa and intestinal parasites decreased sharply compared with the results of previous two surveys, and the rate of intestinal helminth infection also dropped sharply compared with the second survey. The numbers of protozoa, helminth and intestinal parasites detected in this survey were all less than the numbers found in the previous two surveys. Conclusions: Compared the results of three surveys in Henan, the infection rate of protozoa and intestinal parasites showed a downward trend. The prevention and treatment of Enterobius vermicularis infection in children should be the key point of parasitic disease control in the future.

Prevalence of Strongyloides stercoralis infection and other soil-transmitted helminths by cross-sectional survey in a rural community in Gisagara District, Southern Province, Rwanda.

Background Strongyloides stercoralis is one of the most neglected tropical diseases. Sparse, dated central African and Rwandan data on seroprevalence are available to guide public health efforts and clinical care.MethodsIn February 2016 we conducted a community-based cross-sectional study among 539 asymptomatic participants in a rural area in the Gisagara District, Southern Province, Rwanda. Direct faecal smear (DFS) and modified Koga agar plate culture (APC) were used to detect S. stercoralis infection in a single stool sample. Data on other soil-transmitted helminths diagnosed by DFS were also recorded.ResultsFour intestinal helminth infections were diagnosed, with S. stercoralis (17.4%) and hookworms (8.2%) seen most often. APC, compared with DFS, increased the diagnosis rate for S. stercoralis from 1.9% to 17.4% (p<0.01). The prevalence was higher in farmers and those with lower socio-economic status. Females were less often infected than males (odds ratio 0.6 [95% confidence interval 0.3 to 0.9], p=0.02).Conclusions S. stercoralis is highly prevalent among the general population in a rural area of Gisagara District, Southern Province, Rwanda. Access to effective diagnosis and treatment is needed for this neglected disease.

Adaptation of the secretome of Echinostoma caproni may contribute to parasite survival in a Th1 milieu.

Echinostoma caproni (Trematoda: Echinostomatidae) is an intestinal trematode, broadly employed to study the host-dependent mechanisms that govern the evolution of intestinal helminth infections. Resistance against E. caproni homologous secondary infections has been reported in mice and appears to be related to the generation of a local Th2 response, whereas Th1 responses promote the development of chronic primary infections. Herein, the ability of E. caproni to modulate its secretome according to the host environment is investigated. A two-dimensional differential in gel electrophoresis (2D-DIGE) analysis was performed to elucidate changes in the excretory/secretory products of E. caproni adults after primary and secondary infections in mice. A total of 16 protein spots showed significant differences between groups, and 7 of them were successfully identified by mass spectrometry. Adult worms exposed to a primary infection appear to upregulate proteins involved in detoxification (aldo-keto reductase), stress response (GroEL), and enhancement of parasite survival (acetyl-CoA A-acetyltransferase and UTP-glucose-1-phosphate urydyltransferase). In contrast, any protein was found to be significantly upregulated after secondary infection. Upregulation of such proteins may serve to withstand the hostile Th1 environment generated in primary infections in mice. These results provide new insights into the resistance mechanisms developed by the parasites to ensure their long-term survival.

Impact of Water, Sanitation and Hygiene Interventions on Growth, Non-diarrheal Morbidity and Mortality in Children Residing in Low- and Middle-income Countries: A Systematic Review

To evaluate the impact of water, sanitation and hygiene (WASH) interventions in children (age <18 y) on growth, non-diarrheal morbidity and mortality in children. Systematic review of randomized controlled trials, non-randomized controlled trials and controlled before-after studies. Low- and middle-income countries. 41 trials with WASH intervention, incorporating data on 113055 children. Hygiene promotion and education (15 trials), water intervention (10 trials), sanitation improvement (7 trials), all three components of WASH (4 trials), combined water and sanitation (1 trial), and sanitation and hygiene (1 trial). (i) Anthropometry: weight, height, weight-for-height, mid-arm circumference; (ii) Prevalence of malnutrition; (iii) Non-diarrheal morbidity; and (iv) mortality. There may be little or no effect of hygiene intervention on most anthropometric parameters (low- to very-low quality evidence). Hygiene intervention reduced the risk of developing Acute respiratory infections by 24% (RR 0.76; 95% CI 0.59, 0.98; moderate quality evidence), cough by 10% (RR 0.90; 95% CI 0.83, 0.97; moderate quality evidence), laboratory-confirmed influenza by 50% (RR 0.5; 95% CI 0.41, 0.62; very low quality evidence), fever by 13% (RR 0.87; 95% CI 0.74, 1.02; moderate quality evidence), and conjunctivitis by 51% (RR 0.49; 95% CI 0.45, 0.55; low quality evidence). There was low quality evidence to suggest no impact of hygiene intervention on mortality (RR 0.65; 95% CI 0.25, 1.7). Improvement in water supply and quality was associated with slightly higher weight-for-age Z-score (MD 0.03; 95% CI 0, 0.06; low quality evidence), but no significant impact on other anthropometric parameters or infectious morbidity (low to very low quality evidence). There was very low quality evidence to suggest reduction in mortality (RR 0.45; 95% CI 0.25, 0.81). Improvement in sanitation had a variable effect on the anthropometry and infectious morbidity. Combined water, sanitation and hygiene intervention improved height-for-age Z scores (MD 0.22; 95% CI 0.12, 0.32) and decreased the risk of stunting by 13% (RR 0.87; 95% CI 0.81, 0.94) (very low quality of evidence). There was no evidence of significant effect of combined WASH interventions on non-diarrheal morbidity (fever, respiratory infections, intestinal helminth infection and school absenteeism) (low- to very-low quality of evidence). Any WASH intervention (considered together) resulted in lower risk of underweight (RR 0.81; 95% CI 0.69, 0.96), stunting (RR 0.77; 95% CI 0.68, 0.86) and wasting (RR 0.12, 0.85) (low- to very-low quality of evidence). Available evidence suggests that there may be little or no effect of WASH interventions on the anthropometric indices in children from low- and middle-income countries. There is low- to very-low quality of evidence to suggest decrease in prevalence of wasting, stunting and underweight. WASH interventions (especially hygiene intervention) were associated with lower risk of non-diarrheal morbidity (very low to moderate quality evidence). There was very low quality evidence to suggest some decrease to no change in mortality. These potential health benefits lend support to the ongoing efforts for provision of safe and adequate water supply, sanitation and hygiene.

Prevalence and Intensity of Intestinal Helminth Infections and Associated Risk Factors among School-Aged Children in Abua/Odual Local Government Area, Rivers State

Prevalence and Intensity of Intestinal Helminth Infections and Associated Risk Factors among School-Aged Children in Abua/Odual Local Government Area, Rivers State

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.

Changing Trend of Infectious Diseases in Nepal.

Many infectious/ communicable diseases (IDs) are endemic in Nepal. Until a decade and half ago, IDs were the major cause of both morbidity and mortality accounting 70% for both. However, as a result of various preventive measures implemented by both the state and non-state actors, the overall IDs have shown a changing (declining) trend. The most impressive decline has been seen in the intestinal helminth infection. Though the overall burden of IDs is decreasing, several newer infectious diseases (emerging infections) namely, dengue fever, scrub typhus, influenza (H5N1 and H1N1), and others are posing a great public health problem. On the other hand, though sporadic, outbreaks of endemic diseases together with HIV-TB coinfection and infection with drug resistance microbes during recent years have constituted a serious public health as well as medical problem. On the contrary, with the decline of IDs, noninfectious diseases (noncommunicable disease, NCD) namely, diabetes, cancer (and cancer therapy), and others are on the rise particularly in urban areas. Hence, currently Nepal is trapped in “double burden” of diseases. Risk of opportunistic infection has increased in immunocompromised person with NCD. To address the present situation, the multi-sectoral plan and strategies developed must be implemented effectively.

Prevalence of anemia and associated factors among school children in Gondar town public primary schools, northwest Ethiopia: A school-based cross-sectional study.

BackgroundAnemia is a global public health problem affecting 305 million school children (SC) worldwide. It has deleterious effects in SC, including lower school achievement due to impaired cognitive development and physical growth, fatigue and poor attention span, and increased morbidity because of reduced resistance to infection. Hence, the aim of this study was to assess the prevalence and associated factors of anemia among SC attending public primary schools in Gondar town, northwest Ethiopia.MethodsA school-based cross sectional study was conducted on a total of 523 SC aged from 6–14 years old. Multi-stage sampling followed by systematic random sampling techniques were employed to select study participants. Data on socio-demographic and socio-economic characteristics, and dietary status of children were collected using pre-tested structured questionnaire through face-to-face interview of children’s caregivers. Anthropometric measurements were taken. Hemoglobin (Hb) concentration was determined by using HemoCue 301+analyser. Stool and blood samples were collected in the school premises, and examined for intestinal and hemoparasites, respectively. Data were entered into Epi Info version 3.5.3 and transferred to SPSS version 20 for analysis. Bivariate and multivariate binary logistic regression models were fitted to identify associated factors of anemia. P-value < 0.05 was considered as statistically significant.ResultOf the total SC participated in the study, 269 (51.4%) were males. The median (inter quartile range (IQR)) age was 12 (10–13) years, and 332 (63.5%) of them were in the age group 11–14 years. About 81 (15.5%; 95%CI: 12.4%, 18.7%) of them were anemic: 56 (69.1%) and 25 (38.9%) of them were mildly and moderately anemic, respectively. Low maternal education (AOR = 2.30; 95%CI: 1.11, 4.78), stunting (AOR = 2.22; 95%CI: 1.30, 3.80), severe food insecurity (AOR = 5.11; 95%CI: 1.53, 17.13), and soil-transmitted helminthic (STH) infection (AOR = 7.13; 95%CI: 3.16, 16.86) were found significantly associated with anemia.ConclusionAnemia among SC was found to be a mild public health problem. It was strongly associated with low maternal education, food insecurity, stunting and intestinal helminthic infection. Focused policies and strategies towards the above factors should be designed to reduce anemia among SC.

Functional specialization of intestinal dendritic cell subsets during Th2 helminth infection in mice.

Dendritic cells (DCs) are essential in dictating the nature and effectiveness of immune responses. In the intestine DCs can be separated into discrete subsets, defined by expression of CD11b and CD103, each with different developmental requirements and distinct functional potential. Recent evidence has shown that different intestinal DC subsets are involved in the induction of T helper (Th)17 and regulatory T cell responses, but the cells that initiate Th2 immune responses are still incompletely understood. We show that in the Th2 response to an intestinal helminth in mice, only CD11b+ and not CD11b- DCs accumulate in the local lymph node, upregulate PDL2 and express markers of alternative activation. An enteric Th1 response instead activated both CD11b+ and CD11b- DCs without eliciting alternative activation in either population. Functionally, only CD11b+ DCs activated during helminth infection supported Th2 differentiation in naive CD4+ T cells. Together our data demonstrate that the ability to prime Th2 cells during intestinal helminth infection, is a selective and inducible characteristic of CD11b+ DCs.

Epithelial-Cell-Derived Phospholipase A2 Group 1B Is an Endogenous Anthelmintic

SummaryImmunity to intestinal helminth infections has been well studied, but the mechanism of helminth killing prior to expulsion remains unclear. Here we identify epithelial-cell-derived phospholipase A2 group 1B (PLA2g1B) as a host-derived endogenous anthelmintic. PLA2g1B is elevated in resistant mice and is responsible for killing tissue-embedded larvae. Despite comparable activities of other essential type-2-dependent immune mechanisms, Pla2g1b−/− mice failed to expel the intestinal helminths Heligmosomoides polygyrus or Nippostrongylus brasiliensis. Expression of Pla2g1b by epithelial cells was dependent upon intestinal microbiota, adaptive immunity, and common-gamma chain-dependent signaling. Notably, Pla2g1b was downregulated in susceptible mice and inhibited by IL-4R-signaling in vitro, uncoupling parasite killing from expulsion mechanisms. Resistance was restored in Pla2g1b−/− mice by treating infective H. polygyrus L3 larvae with PLA2g1B, which reduced larval phospholipid abundance. These findings uncover epithelial-cell-derived Pla2g1b as an essential mediator of helminth killing, highlighting a previously overlooked mechanism of anti-helminth immunity.