Intestinal Parasites, Anemia and Nutritional Status in Young Children from Transitioning Western Amazon

Gut microbiota of an Amazonian fish in a heterogeneous riverscape: integrating genotype, environment, and parasitic infections

A number of key factors can structure the gut microbiota of fish such as environment, diet, health state, and genotype. Mesonauta festivus, an Amazonian cichlid, is a relevant model organism to study the relative contribution of these factors on the community structure of fish gut microbiota. M. festivus has well-studied genetic populations and thrives in rivers with drastically divergent physicochemical characteristics. Here, we collected 167 fish from 12 study sites and used 16S and 18S rRNA metabarcoding approaches to characterize the gut microbiome structure of M. festivus. These data sets were analyzed in light of the host fish genotypes (genotyping-by-sequencing) and an extensive characterization of environmental physico-chemical parameters. We explored the relative contribution of environmental dissimilarity, the presence of parasitic taxa, and phylogenetic relatedness on structuring the gut microbiota. We documented occurrences of Nyctotherus sp. infecting a fish and linked its presence to a dysbiosis of the host gut microbiota. Moreover, we detected the presence of helminths which had a minor impact on the gut microbiota of their host. In addition, our results support a higher impact of the phylogenetic relatedness between fish rather than environmental similarity between sites of study on structuring the gut microbiota for this Amazonian cichlid. Our study in a heterogeneous riverscape integrates a wide range of factors known to structure fish gut microbiomes. It significantly improves understanding of the complex relationship between fish, their parasites, their microbiota, and the environment. IMPORTANCE The gut microbiota is known to play important roles in its host immunity, metabolism, and comportment. Its taxonomic composition is modulated by a complex interplay of factors that are hard to study simultaneously in natural systems. Mesonauta festivus, an Amazonian cichlid, is an interesting model to simultaneously study the influence of multiple variables on the gut microbiota. In this study, we explored the relative contribution of the environmental conditions, the presence of parasitic infections, and the genotype of the host on structuring the gut microbiota of M. festivus in Amazonia. Our results highlighted infections by a parasitic ciliate that caused a disruption of the gut microbiota and by parasitic worms that had a low impact on the microbiota. Finally, our results support a higher impact of the genotype than the environment on structuring the microbiota for this fish. These findings significantly improve understanding of the complex relationship among fish, their parasites, their microbiota, and the environment.

Inequalities in anemia among Peruvian children aged 6–59 months: A decomposition analysis

Objective

To quantify the inequalities of anemia in Peruvian children aged 6–59 months and uncover its contributing factors.

Materials and methods

We conducted a cross-sectional study based on the secondary data analysis of the 2021 Peruvian Demographic and Health Survey (DHS). Our sample included Peruvian children aged 6–59 months with complete data for the variables of interest. Anemia was defined as having a hemoglobin level of less than 11 g/dL, adjusted by altitude. Erreygers Concentration Index (ECI) and concentration curves were computed to estimate the socio-economic inequality in anemia among Peruvian children. Moreover, ECI was decomposed to figure out the contributing factors to the inequality of anemia and the residual variation.

Results

Nationwide, the prevalence of anemia in Peruvian children was 29.47%. We found a pro-poor inequality regarding anemia at the national level (ECI = −0.1848). The determinants included in the model explained 81.85% of the overall socio-economic inequality in anemia. The largest contribution to inequality was from household- and community-related factors. Having a higher mother’s education level (26.26%) and being from the highlands (24.91%) were the major significant contributors to the overall health inequality.

Conclusion

Almost one-third of Peruvian children have anemia. A pro-poor inequality of anemia in Peruvian children was found. Public policies ought to address the major contributing factors of anemia inequality.

Parasitic infections as potential risk factors for attention deficit hyperactivity disorder (ADHD) in children

Attention deficit hyperactivity disorder (ADHD) represents a mysterious neuropsychiatric alarming concern due to indefinite etiopathogenesis among children. Notably, the studies which investigated the correlation between ADHD and parasitic infections are insufficient. Therefore, this research aimed to assess the correlation between ADHD and some tissue dwelling and intestinal parasitic infections in children. The study was conducted on 200 children, including 100 children suffering from ADHD (Group I) and 100 healthy children as a control group (Group II). All caregivers fulfilled predesigned sociodemographic form and Conners parent rating scale (CPRS-48) questionnaire. Blood samples were collected to determine hemoglobin level as well as relative eosinophilic count. The presence of anti-Toxoplasma IgG and anti-Toxocara IgG in serum by Enzyme-Linked Immunosorbent Assay (ELISA) was further investigated. Also, micronutrients as zinc, iron, and copper levels were measured. Schistosoma antigen was investigated in urine samples. Stool samples were subjected to direct wet smear, concentration technique and modified Ziehl-Neelsen (MZN) staining for coccidian parasites detection. Cryptosporidium parvum, Giardia lamblia and Entamoeba histolytica antigens were investigated in stool samples. Group I expressed more liability to sociodemographic risk factors, decreased levels of Hb, iron, zinc, and copper with statistically significant difference (P < 0.001). Comparison between Group I and Group II regarding the detected parasitic infections exhibited statistically significant difference except Schistosoma antigen positivity which expressed no statistical significance. The present study concluded that the parasitic infections with their consequences are potential risk factors in children with ADHD indicating that their early diagnosis and treatment may help in ADHD prevention.

Fish and Fish-Based Products for Nutrition and Health in the First 1000 Days: A Systematic Review of the Evidence from Low and Middle-Income Countries

Fish provide essential nutrients for the critical window of growth and development in the first 1000 d of life and are thus an attractive option for inclusion in nutrition-sensitive and nutrition-specific programming. We conducted a systematic review of the evidence for fish and fish-based products for nutrition and health outcomes during the first 1000 d of life in low- and middle-income countries, searching the peer-reviewed and gray literature from 1999 to 2020. Databases included PubMed, Web of Science, Embase, ProQuest, and the Clinical Trials repository. Our search returned 1135 articles, 39 of which met the inclusion criteria. All studies were dual evaluated for risk of bias. Of the included studies, 18 measured maternal health and nutrition outcomes and 24 measured infant/child outcomes (3 measured both). Our search uncovered 10 impact evaluations, all of which measured consumption of fish or fish-based complementary food products in children aged 6-24 mo. We did not find strong evidence for fish consumption in children improving child growth from the impact evaluations; however, the studies were highly heterogeneous in their design and likely underpowered to detect an effect. Results from observational studies were mixed but provided evidence that adding fish to maternal and child diets is associated with improved nutrition outcomes, such as reducing the risk of anemia and improving vitamin D status. Given the nutrient richness of fish and the fact that production is often more environmentally friendly as compared with other animal source foods, more robust evidence is needed on the role of fish consumption in nutrition interventions to inform policy and programming recommendations in low- and middle-income countries.

Wildmeat consumption and child health in Amazonia

Consuming wildmeat may protect against iron-deficiency anemia, a serious public health problem globally. Contributing to debates on the linkages between wildmeat and the health of forest-proximate people, we investigate whether wildmeat consumption is associated with hemoglobin concentration in rural and urban children (< 5 years old) in central Brazilian Amazonia. Because dietary practices mediate the potential nutritional benefits of wildmeat, we also examined whether its introduction into children's diets is influenced by rural/urban location or household socio-economic characteristics. Sampling 610 children, we found that wildmeat consumption is associated with higher hemoglobin concentration among the rural children most vulnerable to poverty, but not in the least vulnerable rural, or urban children. Rural caregivers share wildmeat with children earlier-in-life than urban caregivers, potentially because of cultural differences, lower access to domesticated meat, and higher wildmeat consumption by rural households (four times the urban average). If wildmeat becomes unavailable through stricter regulations or over-harvesting, we predict a ~ 10% increased prevalence of anemia among extremely poor rural children. This modest protective effect indicates that ensuring wildmeat access is, alone, insufficient to control anemia. Sustainable wildlife management could enhance the nutritional benefits of wildlife for vulnerable Amazonians, but reducing multidimensional poverty and improving access to quality healthcare are paramount.

A systematic review and meta-analysis on the co-infection of Helicobacter pylori with intestinal parasites: public health issue or neglected correlation?

The current study was conducted to assess the prevalence and odds ratio (OR) of co-infection of Helicobacter pylori (H. pylori) and intestinal parasites (IPs). English databases were searched. A total of 18 studies including 14 studies with cross-sectional design (a total of 3739 participants) and 4 studies with case-control design (397 patients and 320 controls) met the eligibility criteria. The pooled prevalence of H. pylori, intestinal parasite infections (IPIs), and their co-infections in different populations were 48.3% (95% CI, 34.1-62.8%), 15.4% (95% CI, 10-22.8%), and 11% (95% CI, 6.7-17.6%), respectively. The co-infection of H. pylori and Giardia was 7.6% (95% CI, 4.9-11.7%). Although statistically not significant, the risk of co-infection of H. pylori and IPIs was higher in case group compared to control group (OR, 1.59; 95% CI, 0.77-3.25). The overlaps between H. pylori and IPIs in countries with lower human development index (HDI) and income levels were high.

An Assessment of Health Outcomes and Methylmercury Exposure in Munduruku Indigenous Women of Childbearing Age and Their Children under 2 Years Old

In line with the 1000-day initiative and the Sustainable Development Goals (SDG) 2 and 3, we present a cross-sectional analysis of maternal health, infant nutrition, and methylmercury exposure within hard-to-reach indigenous communities in the state of Pará, Brazilian Amazon. We collected data from all women of childbearing age (i.e., 12-49) and their infants under two years old in three Munduruku communities (Sawré Muybu, Sawré Aboy, and Poxo Muybu) along the Tapajos River. We explored health outcomes through interviews, vaccine coverage and clinical assessment, and determined baseline hair methylmercury (H-Hg) levels. Hemoglobin, infant growth (Anthropometric Z scores) and neurodevelopment tests results were collected. We found that 62% of women of childbearing age exceeded the reference limit of 6.0 μg/g H-Hg (median = 7.115, IQR = 4.678), with the worst affected community (Sawré Aboy) registering an average H-Hg concentration of 12.67 μg/g. Half of infants aged under 24 months presented with anemia. Three of 16 (18.8%) infants presented H-Hg levels above 6.0 µg/g (median: 3.88; IQR = 3.05). Four of the 16 infants were found to be stunted and 38% of women overweight, evidencing possible nutritional transition. No infant presented with appropriate vaccination coverage for their age. These communities presented with an estimated Infant Mortality Rate (IMR) of 86.7/1000 live births. The highest H-Hg level (19.6 µg/g) was recorded in an 11-month-old girl who was found to have gross motor delay and anemia. This already vulnerable indigenous Munduruku community presents with undernutrition and a high prevalence of chronic methylmercury exposure in women of childbearing age. This dual public health crisis in the context of wider health inequalities has the potential to compromise the development, health and survival of the developing fetus and infant in the first two critical years of life. We encourage culturally sensitive intervention and further research to focus efforts.

Mercury in blood, hair, and feces from subsistence fish-eating riverines of the Madeira River Basin (Western Amazon)

BACKGROUND

The Madeira River (Amazon Basin) has been impacted by activities related to artisanal and small-scale gold mining (ASGM), deforestation and burning (for timber, agriculture, and hydroelectric dam projects). All these activities contribute to environmental mercury (Hg) release and cycling into the Amazon ecosystem and thus to changing lifestyles.

METHOD

We assessed exposure to total and MeHg in two small riverine communities of the Madeira River (Amazon): Lago Puruzinho (LP, n = 26 families) and São Sebastião do Tapurú (SST, n = 31 families). Samples of human hair (n = 137), blood (n = 39), and feces (n = 41) were collected from adults and children (0-15 years of age).

RESULTS

In women of childbearing age from LP village, the mean blood total-Hg (THg) (45.54 ± 24.76 μg.L^-1) and MeHg (10.79 ± 4.36 μg.L^-1) concentrations were significantly (p = 0.0024; p < 0.0001, respectively) higher than in women from SST village (THg: 25.32 ± 16.75 μg.L^-1; MeHg: 2.32 ± 1.56 μg.L^-1) village; the trend in hair-Hg persisted but was statistically significant (p < 0.0145) only for THg (LP, 11.34 ± 5.03 μg. g^-1; SST, 7.97 ± 3.51 μg. g^-1). In women, the median hair:blood ratio of total Hg was 269. In children, the mean hair THg concentrations were 6.07 ± 3.60 μg. g^-1 and 6.47 ± 4.16 μg. g^-1 in LP and SST; thus, not significantly different (p = 0.8006). There was a significant association (p < 0.001) between hair-Hg concentrations of mothers and their respective children. The excretion of Hg in feces of women (0.52 μg. g^-1 dw) was not significantly different from children (0.49 μg. g^-1 dw). The only statistically significant correlation between Hg in feces and in hair was found in children, (n = 16, r_s = 0.38, p = 0.005). Significant relationship was seen between the levels of THg in blood and hair of women from LP and SST. Based on hair-Hg concentrations, fish consumption rate ranged from 94.5 to 212.3 g.day^-1.

CONCLUSION

Women and children excrete THg in feces in comparable concentrations. However, the mean fish consumption rate and blood MeHg are higher in the most remote villagers. Mother`s hair-Hg concentration is a good predictor of children's hair-Hg.

Helminthiasis, iron intake, and hemoglobin levels in pregnant women

The study aims to analyze the correlation of helminthiasis, iron intake, and hemoglobin levels in pregnant women in the Public Health Center of Kemusu 2 Boyolali, Central Java, Indonesia. A cross-sectional research design was applied to 164 pregnant women who are in the second-third trimester and selected using simple random sampling. The Cyanmethemoglobin tool was utilized to measure the respondents' hemoglobin levels. The iron intake was obtained using the Semi-Quantitative Food Frequency Questionnaire (SQ-FFQ). Data analysis applied the Pearson's correlation test. This study discovered that 12.2% of subjects are infected by Ascaris lumbricoides; 34.1% and 36.6% of the subjects suffer from iron intake deficiency and anemia. There is a correlation between helminthiasis, iron intake, and hemoglobin levels in pregnant women (p=.005 and p=.007). Nutrition program is still needed to prevent the helminthiasis, reduce the prevalence of anemia in pregnant women, and improve their iron intake through supplementation and nutrition education.

Prevalence of intestinal parasitic infections and Campylobacter spp. among children with gastrointestinal disorders in Tehran, Iran

Co-infection of intestinal parasitic infections (IPIs) and Campylobacter spp. are public health problem in both developing and developed countries. This study was conducted to determine prevalence of IPIs and Campylobacter spp. among children with gastrointestinal disorders in Tehran. In this descriptive cross-sectional survey, 283 fresh stool samples were collected from all individuals and examined by standard parasitological methods including direct slide smear, formalin-ether concentration, trichrome staining, modified Ziehl-Neelsen staining, and chromotrope 2R staining techniques were used for detection of intestinal protozoa and helminths. Furthermore, culture and multiplex-PCR were also used to identify the species of Campylobacter. Data analysis was performed using SPSS version 16. IPIs were detected microscopically in 22.26% of the total study population, with a higher prevalence in Giardia duodenalis (7.06%) and Blastocystis hominis (7.06%). Campylobacter were detected molecularly in 14.8% (95.2% of C. jejuni vs. 4.8% of C. coli) of the total study populations; of these, 3.5% had co-existence with IPIs colonized patients. Our results showed a relatively high prevalence of IPIs and Campylobacter in children with diarrhea. Further research is needed to better understand their co-infection and ensure future advances in clinical trials, testing, and development of therapeutic approaches for these pathogens.

Prevalence of intestinal parasitic infection and its associated factors among primary school students in Ethiopia: A systematic review and meta-analysis

Introduction

Intestinal parasitic infection are a major public health concern affecting both children and adolescents in Ethiopia. The aim of this systematic review and meta-analysis was to determine pooled prevalence and associated factors of intestinal parasitic infection in this target group.

Method

We systematically retrieved available articles on the prevalence of intestinal parasitic infection following database searches using PubMed, Scopus, Cochrane Library, and Science Direct between March 1 and May 27, 2020. Two authors independently extracted all relevant data using a standardized Microsoft Excel data extraction form. Heterogeneity among included studies was assessed with the Higgins I² tests. The pooled estimates and associated factors were assessed with a random-effects model using Stata/se Version 14.

Result

We retrieved 30 eligible articles with a pooled sample size of 14,445 primary school children with response rate of 97.8%. Entamoeba spp (16.11%), Ascaris lumbricoides (13.98%), hookworm (12.51%) and Giardia lamblia (9.98%) are the top causes of intestinal parasitic infection among primary school children in Ethiopia. The pooled prevalence for at least one intestinal parasitic infection was 46.09 (95% CI: 38.50, 53.68). Heterogeneity was assessed by doing subgroup analysis by study province/region. Thus, the highest prevalence of 66.6% (95% CI: 55.5, 77.7) occurred in Tigray region, which was followed by Southern Nations, Nationalities, and Peoples’ Region at 50.8% (95% CI: 33.1, 68.5). No latrine availability (OR = 4.39: 2.50,7.73), no fingernail hygiene (OR = 2.37: 1.67, 3.35), open defecation (OR = 1.67:1.64,4.36), no formal maternal education (OR = 2.02: 1.18,3.47), rural residence (OR = 1.88: 1.46, 2.41), no habit of wearing shoes (OR = 2.66: 1.79, 3.96), non-pipe source of drinking water (OR = 1.99: 1.42,2.76), no regular hand washing practices (OR = 3.45:1.85,6.47), and no habit of washing fruits and vegetables (OR = 1.59:1.01,2.49) were associated with parasitic infection.

Conclusions

The prevalence of intestinal parasitic infection was high (46%). Attention should be given to promoting personal hygiene, latrine utilization, wearing shoes, avoiding eating raw food, creating awareness for those mothers who lack formal education. Moreover, future research ideally will expand on the topic by conducting research in regions which have no prior research.

Intestinal parasitic infections are distributed virtually with high prevalence rates in many regions, especially in low and middle income countries which intimately linked to age group, poverty and inadequate access to water, sanitation and hygiene. It is now a day’s one of the neglected tropical disease. We had searched different individual studies on intestinal parasitic infections to generate the pooled effect and recommend for the concerned body. We head included 30 different articles with a sample size of 14,445 and we have found a pooled prevalence of 46.09%. This finding indicates the prevalence of parasitic infection was almost near to half. Therefore every concerned body should give emphasize to prevent and control parasitic infection infestation.