Impact of Childhood Nutritional Status on Pathogen Prevalence and Severity of Acute Diarrhea

Clinical and nutritional correlates of bacterial diarrhoea aetiology in young children: a secondary cross-sectional analysis of the ABCD trial

OBJECTIVE

The objective was to assess the association between nutritional and clinical characteristics and quantitative PCR (qPCR)-diagnosis of bacterial diarrhoea in a multicentre cohort of children under 2 years of age with moderate to severe diarrhoea (MSD).

DESIGN

A secondary cross-sectional analysis of baseline data collected from the AntiBiotics for Children with Diarrhoea trial (NCT03130114).

PATIENTS

Children with MSD (defined as >3 loose stools within 24 hours and presenting with at least one of the following: some/severe dehydration, moderate acute malnutrition (MAM) or severe stunting) enrolled in the ABCD trial and collected stool sample.

STUDY PERIOD

June 2017-July 2019.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Likely bacterial aetiology of diarrhoea. Secondary outcomes included specific diarrhoea aetiology.

RESULTS

A total of 6692 children with MSD had qPCR results available and 28% had likely bacterial diarrhoea aetiology. Compared with children with severe stunting, children with MAM (adjusted OR (aOR) (95% CI) 1.56 (1.18 to 2.08)), some/severe dehydration (aOR (95% CI) 1.66 (1.25 to 2.22)) or both (aOR (95% CI) 2.21 (1.61 to 3.06)), had higher odds of having likely bacterial diarrhoea aetiology. Similar trends were noted for stable toxin-enterotoxigenic Escherichia coli aetiology. Clinical correlates including fever and prolonged duration of diarrhoea were not associated with likely bacterial aetiology; children with more than six stools in the previous 24 hours had higher odds of likely bacterial diarrhoea (aOR (95% CI) 1.20 (1.05 to 1.36)) compared with those with fewer stools.

CONCLUSION

The presence of MAM, dehydration or high stool frequency may be helpful in identifying children with MSD who might benefit from antibiotics.

Etiology of diarrheal hospitalizations following rotavirus vaccine implementation and association of enteric pathogens with malnutrition among under-five children in India

Malnourished children are at higher risk of mortality and morbidity following diarrheal illness and certain enteropathogens have been associated with malnutrition in children. Very few studies have comprehensively looked at the etiology of diarrhea in malnourished children and most have used conventional diagnostic methods with suboptimal sensitivity. We used a highly sensitive molecular approach against a broad range of pathogens causing diarrhea and examined their association with malnutrition. In addition, we looked at the pathogen diversity of pediatric diarrhea, three years after the nationwide rotavirus vaccine introduction to understand the evolving landscape of pathogens, which is crucial for planning strategies to further reduce the diarrhea burden. Clinical details and diarrheal stool samples were collected from hospitalized children aged < 5 years from three sentinel sites in India for a period of one year. The samples were tested by qPCR for 16 established causes of diarrhea using TaqMan Array Cards. A total of 772 children were enrolled, from whom 482 (62.4%) stool specimens were tested. No specific pathogen was associated with diarrhea among children with acute or chronic malnutrition compared to those with better nutritional status. Overall, adenovirus was the leading pathogen (attributable fraction (AF) 16.9%; 95% CI 14.1 to 19.2) followed by rotavirus (AF 12.6%; 95% CI 11.8 to 13.1) and Shigella (AF 10.9%; 95% CI 8.4 to 16.4). The majority of diarrhea requiring hospitalization in children aged < 2 years could be attributed to viruses, while Shigella was the most common pathogen among children aged > 2 years. These data on the prevalence and epidemiology of enteropathogens identified potential pathogens for public health interventions.

Prevalence and Correlates of Stunting among a High-Risk Population of Kenyan Children Recently Hospitalized for Acute Illnesses

Stunting (length/height-for-age z-score < -2) is associated with significant morbidity and mortality among children under 5 years of age in sub-Saharan Africa. Children who are stunted and recently hospitalized for acute illness may be at particularly elevated risk for post-discharge mortality. In this cross-sectional analysis, we measured the prevalence of stunting at hospital discharge and identified host, caregiver, and environmental correlates of stunting among children aged 1-59 months in Western Kenya enrolled in the Toto Bora Trial. Child age- and site-adjusted prevalence ratios were estimated using Poisson regression. Of the 1,394 children included in this analysis, 23% were stunted at hospital discharge. Older children (12-23 months and 24-59 months versus 0-5 months) had a higher prevalence of stunting (adjusted prevalence ratio [aPR]: 1.58; 95% CI: 1.04-2.36 and aPR: 1.59; 95% CI: 1.08-2.34, respectively). HIV-exposed, uninfected children (aPR: 1.94; 95% CI: 1.39-2.70), children with HIV infection (aPR: 2.73; 95% CI: 1.45-5.15), and those who were never exclusively breastfed in early life (aPR 2.51; 95% CI: 1.35-4.67) were more likely to be stunted. Caregiver education (primary school or less) and unimproved sanitation (pit latrine without slab floor or open defecation) were associated with increased risk of stunting (aPR: 1.94; 95% CI: 1.54-2.44; aPR: 1.99; 95% CI: 1.20-3.31; aPR: 3.57; 95% CI: 1.77-7.21, respectively). Hospital discharge represents an important opportunity for both identifying and delivering targeted interventions for nutrition-associated poor outcomes among a high-risk population of children.

A foundational approach to culture and analyze malnourished organoids

The gastrointestinal (GI) epithelium plays a major role in nutrient absorption, barrier formation, and innate immunity. The development of organoid-based methodology has significantly impacted the study of the GI epithelium, particularly in the fields of mucosal biology, immunity, and host-microbe interactions. Various effects on the GI epithelium, such as genetics and nutrition, impact patients and alter disease states. Thus, incorporating these effects into organoid-based models will facilitate a better understanding of disease progression and offer opportunities to evaluate therapeutic candidates. One condition that has a significant effect on the GI epithelium is malnutrition, and studying the mechanistic impacts of malnutrition would enhance our understanding of several pathologies. Therefore, the goal of this study was to begin to develop methodology to generate viable malnourished organoids with accessible techniques and resources that can be used for a wide array of mechanistic studies. By selectively limiting distinct macronutrient components of organoid media, we were able to successfully culture and evaluate malnourished organoids. Genetic and protein-based analyses were used to validate the approach and confirm the presence of known biomarkers of malnutrition. Additionally, as proof-of-concept, we utilized malnourished organoid-derived monolayers to evaluate the effect of malnourishment on barrier formation and the ability of the bacterial pathogen Shigella flexneri to infect the GI epithelium. This work serves as the basis for new and exciting techniques to alter the nutritional state of organoids and investigate the related impacts on the GI epithelium.

The diagnosis and management of dehydration in children with wasting or nutritional edema: A systematic review

Dehydration is a major cause of death among children with wasting and diarrhea. We reviewed the evidence for the identification and management of dehydration among these children. Two systematic reviews were conducted to assess 1) the diagnostic performance of clinical signs or algorithms intended to measure dehydration, and 2) the efficacy and safety of low-osmolarity ORS versus ReSoMal on mortality, treatment failure, time to full rehydration, and electrolyte disturbances (management review). We searched PubMed/Medline, Embase, and Global Index Medicus for studies enrolling children 0-60 months old with wasting and diarrhea. The diagnostic review included four studies. Two studies found the Integrated Management of Childhood Illness (IMCI) and the Dehydration: Assessing Kids Accurately (DHAKA) algorithms had similar diagnostic performance, but both algorithms had high false positive rates for moderate (41% and 35%, respectively) and severe (76% and 82%, respectively) dehydration. One further IMCI algorithm study found a 23% false positive rate for moderate dehydration. The management review included six trials. One trial directly compared low osmolarity ORS to ReSoMal and found no difference in treatment failure rates, although ReSoMal had a shorter duration of treatment (16.1 vs. 19.6 hours, p = 0.036) and a higher incidence of hyponatremia. Both fluids failed to correct a substantial number of hypokalemia cases across studies. In conclusion, the IMCI dehydration assessment has comparable performance to other algorithms among wasted children. Low osmolarity ORS may be an alternative to ReSoMal for children with severe wasting, but might require additional potassium to combat hypokalemia.

Family MUAC supported by a two-way SMS platform for identifying children with wasting: the Mama Aweza randomised controlled trial

Background

Effective methods of preventing and identifying childhood wasting are required to achieve global child health goals. Family mid-upper arm circumference (MUAC) programs train caregivers to screen their child for wasting with MUAC tapes. We assessed the effectiveness of a two-way short message service (SMS) platform (referred to as the Maternally Administered Malnutrition Monitoring System [MAMMS]) in western Kenya.

Methods

In this individual-level randomised controlled trial in two rural countries in western Kenya, children (aged 5-12 months) were randomly allocated (1:1) to receive either standard care (SOC) or MAMMS. Randomisation method was permuted-block randomisation with a block size of 10. Eligible participants were children attending maternal child health clinics in the two counties whom had a MUAC between 12.5 and 14.0 cm. The MAMMS group received two MUAC tapes and weekly SMS reminders to screen their child's MUAC. The SOC group received routine community health volunteer services and additional quarterly visits from the study team. The primary analysis used a cox proportional hazards model to compare SOC and MAMMS time-to-diagnosis of wasting (MUAC <12.5 cm) confirmed by a health professional during 6-months follow-up. Secondary outcomes were days from enrolment to treatment initiation among children with wasting, proportion of all children with wasting who were identified by the two approaches (treatment coverage), mean MUAC at treatment initiation, and duration of wasting treatment. This trial was registered on ClinicalTrials.gov, NCT03967015.

Findings

Between August 1, 2019 and January 31, 2022, 1200 children were enrolled, among whom the incidence of confirmed wasting was 37% lower in the MAMMS group (hazard ratio: 0.63, 95% CI: 0.42-0.94, p = 0.022). Among children with wasting, the median number of days-to-diagnosis was similar between study groups (MAMMS: 63 days [interquartile range (IQR): 23-92], SOC: 58 days [IQR: 22-94]). Treatment coverage in the MAMMS group was 83.3% (95% CI: 39.9-100.0) while coverage in the SOC group was 55.6% (95% CI: 22.3-88.9%, p = 0.300). Treatment duration and mean MUAC at treatment initiation were similar between groups.

Interpretation

Family MUAC supported by SMS was associated with a 37% reduction in wasting among young children. Empowering caregivers to monitor their child's nutritional status at home may prevent a substantial proportion of moderate wasting.

Funding

Thrasher Research Foundation and Pamela and Evan Fowler.

Examining comorbidities in children with diarrhea across four provinces of Mozambique: A cross-sectional study (2015 to 2019)

Comorbidities are defined as the simultaneous occurrence of two or more diseases within the same individual. Comorbidities can delay a patient's recovery and increase the costs of treatment. Assessing comorbidities can provide local health care policy-makers with evidence of the most common multi-health impairments in children. This could aid in redirecting and integrating care and treatment services by increasing health facilities the awareness and readiness of health facilities. The present analysis aims to determine the frequency and associated factors of comorbidities in children with diarrhea in Mozambique. A cross-sectional hospital-based analysis was conducted between January 2015 and December 2019 in children up to 59 months of age who were admitted with diarrhea in six reference hospitals in Mozambique. These hospitals are distributed across the country's three regions, with at least one hospital in each province from each region. Sociodemographic and clinical data were obtained through semi-structured interviews and by reviewing the child clinical process. Descriptive statistics, and Mann-Whitney-U tests were used. Crude and adjusted logistics regression models were built. P-values < 0.05 were considered statistically significant. Comorbidities were observed in 55.5% of patients (389/701; 95%CI: 51.8-59.1). Wasting was the most common comorbidity (30.2%; 212/701) and pneumonia was the least common (1.7%; 12/701). Children born with a low birth weight were 2.420 times more likely to have comorbidities, adjusted odds ratio: 2.420 (95% CI: 1.339-4374). The median (interquartile range) duration of hospitalization was significantly higher in children with comorbidities than without comorbidities, 5 days (3-7) and 4 days (3-6), respectively (p-value < 0.001). One in every two children with diarrhea in Mozambique has an additional health impairment, and this increases the length of their hospital stay.

Prevalence of enteric bacterial pathogens in diarrheic under-five children and their association with the nutritional status in Bahir Dar Zuria District, Northwest Ethiopia

BACKGROUND

Diarrheal disease is one of the leading causes of child mortality in low and middle-income countries. Low nutritional status and bacterial infections contribute to growth deficiency and death in children. But there is a gap in identifying the bacterial etiology of diarrheal diseases and their association with the nutritional status of under-five children. This study aimed to determine the bacterial etiology of diarrheal diseases and their association with the nutritional status of diarrheic under-five children.

METHODS

A cross-sectional study was carried out from February 2021 to March 2022 at seven Health Centers in Bahir Dar Zuria district, Ethiopia. A total of 196 diarrheic under-five children visiting the health centers were included in the study. Stool samples were collected from each child for the isolation of Salmonella, Shigella, and E.coli O157:H7. The demographic characteristics and symptoms of children were obtained from parents/guardians. The weight, height, and age of each child were recorded and anthropometric indices were determined by WHO Anthro version 3.2.2 software. The association between bacterial prevalence and the nutritional status of children was analyzed by SPSS version 26 software using Binary logistic regression. All analyses were conducted at a 95% confidence interval and significant association was determined using a p-value < 0.05.

RESULTS

Of the total children included in the study, 13.1% had either E.coli O157:H7, Shigella, or Salmonella. Watery diarrhea and fever were the most clinical characteristics observed in children who are positive for enteric bacteria. The prevalence of stunted, underweight, and wasted was 56.6%, 24.4%, and 13.2% respectively. Children with wasting were significantly associated with Salmonella detection (OR = 7.2, CI, 1.38-38.1, P = 0.02) whereas stunted and underweight were not associated with bacterial prevalence.

CONCLUSION

Overall, the prevalence of bacterial pathogens in the study area is high. Stunting, wasting, and being underweight are important nutritional deficits of diarrheic under-five children in the study site. Further studies targeting possible sources of bacteria and determinants of malnutrition in children are suggested. Health sectors found in the district should increase their effort to enhance good nutritional practice through health education and treatment of malnourished children by the provision of micronutrients.

Infection With Escherichia Coli Pathotypes Is Associated With Biomarkers of Gut Enteropathy and Nutritional Status Among Malnourished Children in Bangladesh

Escherichia coli (E. coli) pathotypes are the most common cause of diarrhea, especially in developing countries. Environmental Enteric Dysfunction (EED) is presumed to be the result of infection with one or more pathotypes and can affect intestinal health and childhood growth. We sought to investigate the association of E. coli pathotypes infection with biomarkers of EED and nutritional status among slum-dwelling malnourished children in Bangladesh. This study comprised a total of 1050 stunted and at risk of stunting children. TaqMan Array Card assays were used to determine the presence of E. coli pathotypes in feces. Prevalence of infection with EAEC was highest (68.8%) in this cohort of children, followed by EPEC (55.9%), ETEC (44%), Shigella/EIEC (19.4%) and STEC (3.2%). The levels of myeloperoxidase and calprotectin were significantly higher in EAEC (P=0.02 and P=0.04), EPEC (P=0.02 and P=0.03) and Shigella/EIEC (P=0.05 and P=0.02) positive participants while, only calprotectin was significantly higher in ETEC (P=0.01) positive participants. Reg1B was significantly higher in participants with EAEC (P=0.004) while, neopterin levels were significantly lower in ETEC (P=0.003) and Shigella/EIEC (P=0.003) positive cases. A significant positive relationship was observed between EAEC and fecal levels of Reg1B (β = 0.28; 95% CI = 0.12, 0.43; p-value<0.001). Besides, ETEC was found to be positively and significantly associated with the levels of calprotectin (β = 0.14; 95 percent CI = 0.01, 0.26; p-value=0.037) and negatively with neopterin (β = -0.16; 95% CI = -0.30, -0.02; p-value=0.021). On the other hand, infection with EPEC was found to be negatively associated with length-for-age (β = -0.12; 95% CI = -0.22, -0.03; p-value=0.011) and weight-for-age (β = -0.11; 95% CI = -0.22, -0.01; p-value=0.037). The study findings suggest that infection with certain E. coli pathotypes (EAEC and ETEC) influences gut health and EPEC is associated with linear growth and underweight in Bangladeshi children.

Readiness of Mozambique Health Facilities to Address Undernutrition and Diarrhea in Children under Five: Indicators from 2018 and 2021 Survey Data

The World Health Organization’s systems framework shows that service delivery is key to addressing pressing health needs. Inadequate healthcare and the lack of healthcare services are factors associated with undernutrition and diarrhea in children under five, two health conditions with high morbi-mortality rates in Mozambique. The aim of the analysis was to determine the readiness score of nutrition and diarrhea services for children under five and the influence of malaria and HIV (Human Immunodeficiency Virus) service readiness on the readiness of these two services. A total of 1644 public health facilities in Mozambique were included from the 2018 Service Availability and Readiness Assessment. Additionally, a cross-sectional study was conducted to determine the availability and readiness scores of nutrition services in 2021 in five referral health facilities. The availability of nutrition and diarrhea services for children is low in Mozambique, with both scoring below 75%. Major unavailability was observed for human resources, guidelines, and training dimensions. Diarrhea (median (IQ): 72.2% (66.7 to 83.3)) and nutrition service readiness (median (IQ): 57.1% (52.4 to 57.1)) scores were significantly different (p < 0.001), while it is desirable for both services to be comprehensively ready. Nutrition services are positively associated with diarrhea service readiness and both services are associated with malaria and HIV service readiness (p < 0.05). None of the health facilities had all tracer items available and none of the facilities were considered ready (100%). There is a persisting need to invest comprehensively in readiness dimensions, within and across child health services.

Association of human milk oligosaccharides and nutritional status of young infants among Bangladeshi mother-infant dyads

Human milk oligosaccharides (HMOs) support the development of a healthy gut microbiome and the growth of infants. We aimed to determine the association of different HMOs with severe acute malnutrition (SAM) among Bangladeshi young infants. This study was nested within a single-blind, randomized, pilot clinical trial (NCT0366657). A total of 45 breastmilk samples from mothers of < 6 months old infants who had SAM (n = 26) or were non-malnourished (n = 19) and were analyzed for constituent HMOs. Of the infants with SAM, 14 (53.85%) had secretor mothers, and 11 (57.89%) of the non-malnourished infants had secretor mothers. A one-unit increase in the relative abundance of sialylated HMOs was associated with higher odds of SAM in age and sex adjusted model (aOR = 2.00, 90% CI 1.30, 3.06), in age, sex, and secretor status adjusted model (aOR = 1.96, 90% CI 1.29, 2.98), and also in age and sex adjusted model among non-secretor mothers (aOR = 2.86, 90% CI 1.07, 7.62). In adjusted models, there was no evidence of a statistically significant association between SAM and fucosylated or undecorated HMOs. Our study demonstrates that a higher relative abundance of sialylated HMOs in mothers’ breastmilk may have a negative impact on young infants’ nutritional status.

Machine learning predictive modelling for identification of predictors of acute respiratory infection and diarrhoea in Uganda's rural and urban settings

Despite the widely known preventive interventions, the dyad of acute respiratory infections (ARI) and diarrhoea remain among the top global causes of mortality in under- 5 years. Studies on child morbidity have enormously applied "traditional" statistical techniques that have limitations in handling high dimension data, which leads to the exclusion of some variables. Machine Learning (ML) models appear to perform better on high dimension data (dataset with the number of features p (usually correlated) larger than the number of observations N). Using Uganda's 2006-2016 DHS pooled data on children aged 6-59 months, I applied ML techniques to identify rural-urban differentials in the predictors of child's diarrhoea and ARI. I also used ML to identify other omitted variables in the current child morbidity frameworks. The predictors were grouped into four categories: child characteristics, maternal characteristics, household characteristics and immunisation. I used 90% of the datasets as a training sets (dataset used to fit (train) a prediction model), which were tested or validated (dataset (pseudo new) used for evaluating the performance of the model on a new dataset) on 10% and 30% datasets. The measure of prediction was based on a 10-fold cross-validation (resampling technique). The gradient-boosted machine (ML technique) was the best-selected model for the identification of the predictors of ARI (Accuracy: 100% -rural and 100%-urban) and diarrhoea (Accuracy: 70%-rural and 100%-urban). These factors relate to the household's structure and composition, which is characterised by poor hygiene and sanitation and poor household environments that make children more suspectable of developing these diseases; maternal socio-economic factors such as education, occupation, and fertility (birth order); individual risk factors such as child age, birth weight and nutritional status; and protective interventions (immunisation). The study findings confirm the notion that ARI and diarrhoea risk factors overlap. The results highlight the need for a holistic approach with multisectoral emphasis in addressing the occurrence of ARI and diarrhoea among children. In particular, the results provide an insight into the importance of implementing interventions that are responsive to the unique structure and composition of the household. Finally, alongside traditional models, machine learning could be applied in generating research hypotheses and providing insight into the selection of key variables that should be considered in the model.

The Effects of Conflicts and Self-Reported Insecurity on Maternal Healthcare Utilisation and Children Health Outcomes in the Democratic Republic of Congo (DRC)

Background The Democratic Republic of Congo (DRC) has experienced political unrest, civil insecurity, and military disputes, resulting in extreme poverty and a severely impaired health care system. To reduce the morbidity and mortality in women and children by strengthening healthcare, this study aimed at exploring the relationship between self-reported insecurity of mothers and maternal health-seeking behaviours and diseases in children in the DRC. Method Data collected from 8144 mothers and 14,403 children from the Multiple Indicators Cluster Survey (MICS) conducted by the National Institute of Statistics in 2017-2018, in collaboration with the United Nations Children's Fund (UNICEF), was used. The severity of the conflict in different provinces was measured using the Uppsala Conflict Data Program (UCDP) reports. Multivariate logistic regression and stratified analysis were utilized to explore the association between conflicts with maternal health-seeking behaviours and diseases among children. Results High self-reported insecurity was positively associated with skilled antenatal care (OR1.93, 95%CI 1.50-2.49), skilled attendants at delivery (OR1.42, 95%CI 1.08-1.87), and early initiation of breastfeeding (OR1.32, 95%CI 1.04-1.68). These associations were more significant in regions with more armed conflict. It was also found that children of mothers with high self-reported insecurity were more likely to suffer from diarrhoea (OR1.47, 95%CI: 1.14-1.88), fever (OR1.23, 95%CI 1.01-1.50), cough (OR1.45, 95%CI 1.19-1.77), and dyspnea (OR2.04, 95%CI 1.52-2.73), than children of mothers with low self-reported insecurity. Conclusions Conflicts increases mothers' insecurities and negatively affects children's development. However, high conflict regions have to increase governmental and international assistance to promote the availability and access to maternal and child health services.

A systematic review and meta-analysis reveal that Campylobacter spp. and antibiotic resistance are widespread in humans in sub-Saharan Africa

INTRODUCTION

Campylobacter spp. are zoonotic bacteria that cause gastroenteritis in humans worldwide, whose main symptom is diarrhea. In certain cases, extra intestinal manifestations may occur, such as Guillain Barré syndrome. The bacteria cause severe diarrhea mostly in children and in immunocompromised individuals. This review aims to address the prevalence of Campylobacter spp. in humans in sub-Saharan Africa. It also aims to understand the impact of HIV in the prevalence, as well as to report data on antibiotic resistance and propose research priorities.

METHODS

We followed PRISMA guidelines to find studies on the occurrence of Campylobacter spp. in humans in all countries from sub-Saharan Africa. Studies published between 2000 and 2020 were searched in PubMed, Cochrane Library, CINAHL, African Index Medicus, African Journals Online, Google Scholar and Science Direct. We have conducted a random-effect meta-analysis and calculated the proportion of resistant isolates to different antibiotics.

RESULTS AND DISCUSSION

We found 77 studies that described such occurrence in humans in 20 out of 53 sub-Saharan African countries. Campylobacter jejuni was the most prevalent species. Pooled prevalence was 9.9% (CI: 8.4%-11.6%). No major variations within the different sub-regions were found. Most studies reported Campylobacter spp. as the cause of diarrhea, mainly in children. Some studies reported the bacteria as a possible etiologic agent of acute flaccid paralysis and urinary tract infection. Campylobacter spp. presented a higher pooled prevalence in HIV infected patients, although not statistically significant. High proportions of resistant strains were reported for many antibiotics, including erythromycin and tetracycline.

CONCLUSION

Campylobacter spp. occur in sub-Saharan Africa, although information is scarce or inexistent for many countries. Research priorities should include investigation of the understudied species; extra intestinal manifestations; the impact of HIV infection and associated risk factors. Control strategies should be reinforced to contain the spread of this pathogen and drug resistance.

The effect of acute malnutrition on enteric pathogens, moderate-to-severe diarrhoea, and associated mortality in the Global Enteric Multicenter Study cohort: a post-hoc analysis

Background

Host vulnerabilities associated with acute malnutrition could facilitate the ability of specific enteric pathogens to cause diarrhoea and associated mortality. Using data from the Global Enteric Multicenter Study, we assessed whether acute malnutrition modifies the association between common enteric pathogens and moderate-to-severe diarrhoea, and whether associations between enteric pathogens and death were modified by acute malnutrition.

Methods

Children with moderate-to-severe diarrhoea and age-matched and community-matched controls were included in this post-hoc analysis if their mid-upper arm circumference had been measured and if they were older than 6 months of age. Acute malnutrition was defined as mid-upper arm circumference below 12·5 cm, capturing both severe acute malnutrition (<11·5 cm) and moderate acute malnutrition (≥11·5 cm and <12·5 cm). We tested whether acute malnutrition modified associations between enteric pathogens and moderate-to-severe diarrhoea in conditional logistic regression models. Among children with moderate-to-severe diarrhoea, Cox proportional hazards regression evaluated the modifying effect of acute malnutrition on the relationship between pathogens and 60-day fatality rate.

Findings

The age, site, and co-infection adjusted odds ratios (aORs) for moderate-to-severe diarrhoea associated with typical enteropathogenic Escherichia coli among children aged 6–11 months was 2·08 (95% CI 1·14–3·79) in children with acute malnutrition, and 0·97 (0·77–1·23) in children with better nutritional status, compared with healthy controls. Enterotoxigenic E coli producing heat-stable toxin among children aged 12–23 months also had a stronger association with moderate-to-severe diarrhoea in children with acute malnutrition (aOR 7·60 [2·63–21·95]) than among similarly aged children with better nutritional status (aOR 2·39 [1·76–3·25]). Results for Shigella spp, norovirus, and sapovirus suggested they had a stronger association with moderate-to-severe diarrhoea than other pathogens among children with better nutritional status, although Shigella spp remained associated with moderate-to-severe diarrhoea in both nutritional groups. 92 (64%) of 144 children with moderate-to-severe diarrhoea who died had acute malnutrition. Pathogen-specific 60-day fatality rates for all pathogens were higher among children with acute malnutrition, but no individual pathogen had a significantly larger increase in its relative association with mortality.

Interpretation

Acute malnutrition might strengthen associations between specific pathogens and moderate-to-severe diarrhoea. However, the strong link between acute malnutrition and mortality during moderate-to-severe diarrhoea in children is not limited to specific infections, and affects a broad spectrum of enteric pathogens. Interventions addressing acute malnutrition could be an effective way to lower the mortality of both childhood malnutrition and diarrhoea.

Funding

The Bill & Melinda Gates Foundation.

Diarrhoeal children with concurrent severe wasting and stunting compared to severe wasting or severe stunting

OBJECTIVE

Children with both severe wasting and severe stunting (SWSS) represent an extreme form of malnutrition and are prone to develop severe infection. The study aims to demonstrate clinical features and aetiology of diarrhoea among children with SWSS compared to those with either severe wasting (SW) or severe stunting (SS), which may help in early identification of high-risk children.

METHODS

Data were extracted from the database of the diarrhoeal disease surveillance system (DDSS) of Dhaka Hospital, icddr,b from 2008 to 2017. Among 14 403 under-five diarrhoeal children, 149 had concurrent SWSS (WLZ/WHZ ˂-3 with LAZ/HAZ ˂-3), 795 had SW (WLZ/WHZ ˂-3 but LAZ/HAZ ≥-3) alone, and 1000 had only SS (LAZ/HAZ ˂-3 but WLZ/WHZ ≥-3).

RESULTS

In logistic regression analysis after adjusting for potential confounders, dehydrating diarrhoea and slum dwelling were independently associated with SWSS vs. SW (P < 0.05). When compared with SS, dehydration and maternal illiteracy were independently associated with SWSS (P < 0.05). In comparison with SW or SS, SWSS less often included infection with rotavirus (P < 0.05). Dehydration was independently associated with SW vs. SS after adjusting for potential confounders (P < 0.05).

CONCLUSION

Children with SWSS more often presented with dehydrating diarrhoea (69%) than children who had either SW (55%) or SS (43%). However, SWSS patients less frequently presented with rotavirus-associated diarrhoeal illnesses. This result underscores the importance of early detection and prompt management of dehydrating diarrhoea in children with concomitant severe wasting and severe stunting to reduce morbidity and mortality in these children, especially in poor settings.

Vibrio cholerae at the Intersection of Immunity and the Microbiome

Vibrio cholerae is a noninvasive pathogen that colonizes the small intestine and produces cholera toxin, causing severe secretory diarrhea. Cholera results in long lasting immunity, and recent studies have improved our understanding of the antigenic repertoire of V. cholerae Interactions between the host, V. cholerae, and the intestinal microbiome are now recognized as factors which impact susceptibility to cholera and the ability to mount a successful immune response to vaccination. Here, we review recent data and corresponding models to describe immune responses to V. cholerae infection and explain how the host microbiome may impact the pathogenesis of V. cholerae In the ongoing battle against cholera, the intestinal microbiome represents a frontier for new approaches to intervention and prevention.

The impact of malnutrition on childhood infections

Purpose of review

Almost half of all childhood deaths worldwide occur in children with malnutrition, predominantly in sub-Saharan Africa and South Asia. This review summarizes the mechanisms by which malnutrition and serious infections interact with each other and with children's environments.

Recent findings

It has become clear that whilst malnutrition results in increased incidence, severity and case fatality of common infections, risks continue beyond acute episodes resulting in significant postdischarge mortality. A well established concept of a ‘vicious-cycle’ between nutrition and infection has now evolving to encompass dysbiosis and pathogen colonization as precursors to infection; enteric dysfunction constituting malabsorption, dysregulation of nutrients and metabolism, inflammation and bacterial translocation. All of these interact with a child's diet and environment. Published trials aiming to break this cycle using antimicrobial prophylaxis or water, sanitation and hygiene interventions have not demonstrated public health benefit so far.

Summary

As further trials are planned, key gaps in knowledge can be filled by applying new tools to re-examine old questions relating to immune competence during and after infection events and changes in nutritional status; and how to characterize overt and subclinical infection, intestinal permeability to bacteria and the role of antimicrobial resistance using specific biomarkers.

Relationships between the weaning period and the introduction of complementary foods in the transmission of gastrointestinal parasitic infections in children in Honduras

PURPOSE

This study was to investigate weaning practices used by mothers when transitioning infants from breast milk to complementary foods and to determine the role these foods have in the transmission of gastrointestinal parasites.

PARTICIPANTS AND METHODS

On average, of the 175 mothers extensively interviewed, 93% said they had breast-fed their infants. Approximately 20.8% of mothers had added some other liquid to their infant's diet at 3 months, while most mothers had added other liquids at 6 months (39.0%) and >6 months (32.1%). Some mothers expanded food offerings to infants before 3 months. The percentage of mothers who had added other liquids to their infants' diet was reported by age of the infant: as early as 1 day (2.5%), <1 week (1.9%), first month (3.1%), 3 months (20.8%), 6 months (39.0%), and >6 months (32.1%). These foods included fruit, vegetables, meat, and grains. The maximum age a child was found to be still breastfeeding was 13 years.

RESULTS

Forty percent of mothers involved in this survey reported that their children were diagnosed and/or treated for gastrointestinal parasitic infection. Routes of infection of protozoan and helminth parasites likely resulted from contaminated complementary foods and water given to infants while still breast-feeding or from contaminated foods after breast-feeding had been completed. Contaminated water is a likely source of protozoan parasites. Contaminated water was fed to infants, mixed with formula or complementary foods, or used to wash bottles for infant feeding. There was an absence of hand-washing by children and mothers before eating or while preparing foods.

CONCLUSION

The major source of soil-transmitted helminth infections was likely the result of unwashed or uncooked pureed fruit or vegetables used as complementary foods, unpasteurized animal milk, insanitary food storage, poor living conditions with exposed dirt floors, and exposure to roaming domestic animals.

Factors associated with wasting among children under five years old in South Asia: Implications for action

South Asia continues to carry the greatest share and number of wasted children worldwide. Understanding the determinants of wasting is important as policymakers renew efforts to tackle this persistent public health and development problem. Using data from national surveys in Bangladesh, India, the Maldives, Nepal, Pakistan and Afghanistan, this analysis explores factors associated with wasting among children aged 0 to 59 months (n = 252,797). We conducted multivariate mixed logistic regression and backwards stepwise methods to identify parsimonious models for each country separately (all p values <0.05). Younger children (0 to 5 months), and those whose mothers had a low body mass index (<18.5 kg/m²) had greater odds of being wasted in all countries. Later birth order, being male, maternal illiteracy, short maternal stature, lack of improved water source, and household poverty were also associated with wasting in various countries, but not systematically in all. Seasonality was also not consistently associated with wasting in the final models. These findings suggest that pre-conception (adolescence), pregnancy and early postpartum, represent windows of opportunity for tackling child wasting, not only stunting. Our analysis suggests that the underlying determinants of wasting and stunting in South Asia are similar, but not universal across geographies. Cost-effective interventions to prevent both stunting and wasting, and to treat severe wasting, need to be scaled up urgently. Separating these two manifestations of child undernutrition in conceptual and programmatic terms may unnecessarily impair progress to reach the Sustainable Development Goals targets aimed at addressing both child stunting and wasting.