Investigating infant feeding development in wild chimpanzees using stable isotopes of naturally shed hair.

Measuring the relative contributions of milk and non-milk foods in the diets of primate infants is difficult from observations. Stable carbon (δ13 C) and nitrogen (δ15 N) isotopes in hair can be used to physiologically track infant feeding through development, but few wild studies have done so, likely due to the difficulty in collecting hair non-invasively. We assessed infant feeding at different ages in wild chimpanzees (Pan troglodytes) at Ngogo, Uganda using δ13 C and δ15 N of keratin in 164 naturally shed hairs from 29 infants (61 hairs), 6 juveniles (7 hairs), 28 mothers (67 hairs) and 14 adult males (29 hairs). Hairs were collected when they stuck to feces during defecation or from the ground after chimpanzees groomed or rested. We could not distinguish between the hairs of infants and mothers using strand length and diameter. Infants 1-2 years old were most enriched in 13 C and 15 N and showed means of 1.1‰ in δ13 C and 2.1‰ in δ15 N above their mothers. Infants at 2 years had hair δ13 C values like those of their mothers, which suggests infants began relying more heavily on plants around this age. While mother-infant δ13 C and δ15 N differences generally decreased with offspring age, as is expected when infants rely increasingly more on independent foraging through development, milk seemed to remain an important dietary component for infants older than 2.5 years, as evidenced by continuing elevated δ15 N. We showed that stable carbon and nitrogen isotopes in naturally shed hairs can feasibly detect trophic level differences between chimpanzee infants and mothers. Since it can mitigate some of the limitations associated with behavioral and fecal stable isotope data, the use of hair stable isotopes is a useful, non-invasive tool for assessing infant feeding development in wild primates.

Human milk immune factors, maternal nutritional status, and infant sex: The INSPIRE study.

OBJECTIVES: Breastfeeding is an energetically costly and intense form of human parental investment, providing sole-source nutrition in early infancy and bioactive components, including immune factors. Given the energetic cost of lactation, milk factors may be subject to tradeoffs, and variation in concentrations have been explored utilizing the Trivers-Willard hypothesis. As human milk immune factors are critical to developing immune system and protect infants against pathogens, we tested whether concentrations of milk immune factors (IgA, IgM, IgG, EGF, TGFß2, and IL-10) vary in response to infant sex and maternal condition (proxied by maternal diet diversity [DD] and body mass index [BMI]) as posited in the Trivers-Willard hypothesis and consider the application of the hypothesis to milk composition. METHODS: We analyzed concentrations of immune factors in 358 milk samples collected from women residing in 10 international sites using linear mixed-effects models to test for an interaction between maternal condition, including population as a random effect and infant age and maternal age as fixed effects. RESULTS: IgG concentrations were significantly lower in milk produced by women consuming diets with low diversity with male infants than those with female infants. No other significant associations were identified. CONCLUSIONS: IgG concentrations were related to infant sex and maternal diet diversity, providing minimal support for the hypothesis. Given the lack of associations across other select immune factors, results suggest that the Trivers-Willard hypothesis may not be broadly applied to human milk immune factors as a measure of maternal investment, which are likely buffered against perturbations in maternal condition.

Household food insecurity is prevalent in a cohort of postpartum women who registered in the Canada Prenatal Nutrition Program in Toronto.

OBJECTIVE: To assess the prevalence, severity and socio-demographic predictors of household food insecurity among vulnerable women accessing the Canada Prenatal Nutrition Program (CPNP) and to examine associations between household food insecurity and breastfeeding practices to 6 months. DESIGN: Cohort investigation pooling data from two studies which administered the 18-item Household Food Security Survey Module at 6 months postpartum and collected prospective infant feeding data at 2 weeks and 2, 4 and 6 months. Household food insecurity was classified as none, marginal, moderate or severe. Logistic regression analyses were performed to assess predictors of household food insecurity and associations between household food security (any and severity) and continued and exclusive breastfeeding. SETTING: Three Toronto sites of the CPNP, a federal initiative targeting socially and/or economically vulnerable women. PARTICIPANTS: 316 birth mothers registered prenatally in the CPNP from 2017 to 2020. RESULTS: Household food insecurity at 6 months postpartum was highly prevalent (44 %), including 11 % in the severe category. Risk of household food insecurity varied by CPNP site (P < 0·001) and was higher among multiparous participants (OR 2·08; 95 % CI 1·28, 3·39). There was no association between the prevalence or severity of food insecurity and continued or exclusive breastfeeding to 6 months postpartum in the adjusted analyses. CONCLUSIONS: Household food insecurity affected nearly half of this cohort of women accessing the CPNP. Further research is needed on household food insecurity across the national CPNP and other similar programmes, with consideration of the implications for programme design, service delivery and policy responses.

Impact of the COVID-19 pandemic on the adaptability and resiliency of school food programs across Canada.

Introduction: Following the sudden closure of schools due to the pandemic in 2020, many school food program (SFP) operators lost their operating venues and had to innovate to continue distributing meals to children. Our objective was to assess the impact of the COVID-19 pandemic on the delivery, adaptability, and resiliency of school food programs across Canada by conducting a systematic rapid review. Materials and methods: Systematic literature searches identified newspaper articles and social media sources related to the adaptations and challenges faced by school food programs across Canada in response to the COVID-19 pandemic. Included sources were assessed and thematically categorized according to the dimensions of the Analysis Grid for Environments Linked to Obesity (ANGELO) and Getting To Equity (GTE) frameworks to identify factors impacting the delivery, adaptability, and resiliency of school food programs in Canada. Results: School food programs in Canada made various efforts to meet existing and new challenges associated with the delivery of these programs to keep feeding school children, particularly those most vulnerable, during the pandemic. Distribution of food kits, prepared meals and gift cards/coupons were successful pathways in ensuring support for food accessibility to students and their families. Increased collaborations between community members and organizations/stakeholders to help maintain food delivery or collectively offer new modes to deliver foods were most frequently cited as key to facilitating school food programming. However, maintenance and sustainability related to operating costs and funding were identified as key challenges to successful school food programming. Conclusion: Our study highlights the swift and substantial transformation school food programs,, underwent in response to the pandemic, driven by the urgent need to ensure that students still had access to nutritious meals and the importance of policy and resource support to bolster the adaptability and resiliency of these programs. Findings on facilitators and challenges to school food programs during the early months of the COVID-19 pandemic can inform development of guidelines to design a robust national Canadian school food program and help make existing programs more sustainable, adaptable, and resilient.

Effects of infant age and sex, and maternal parity on the interaction of lactation with infant feeding development in chimpanzees.

The interaction between infant feeding and maternal lactational physiology influences female inter-birth intervals and mediates maternal reproductive trade-offs. We investigated variation in feeding development in 72 immature wild chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda, and made inferences about maternal lactation over the course of infancy. We compared the percentage (%) of time that mothers nursed infants as a function of infant age and assessed how hourly rates and bout durations of nursing and foraging varied in association with differences in offspring age, sex, and maternal parity. Nursing % times, rates and durations were highest for infants ≤ 6 months old but did not change significantly from 6 months to 5 years old. Nursing continued at a decreasing rate for some 5- to 7-year-olds. Infants ≤ 6 months old foraged little. Foraging rates did not change after 1 year old, but foraging durations and the % time devoted to foraging increased with age. Independent foraging probably became a dietary requirement for infants at 1 year old, when their energy needs may have surpassed the available milk energy. Infants spent as much time foraging by the time they were 4 to 5 years old as adults did. No sex effect on infant nursing or foraging was apparent, but infants of primiparous females had higher foraging rates and spent more time foraging than the infants of multiparous females did. Although no data on milk composition were collected, these findings are consistent with a working hypothesis that like other hominoids, chimpanzee mothers maintained a fixed level of lactation effort over several years as infants increasingly supplemented their growing energy, micronutrient and hydration needs via independent foraging. Plateauing lactation may be a more widespread adaptation that allows hominoid infants time to attain the physiology and skills necessary for independent feeding, while also providing them with a steady dietary base on which they could rely consistently through infancy, and enabling mothers to maintain a fixed, predictable level of lactation effort.

Associations between use of expressed human milk at 2 weeks postpartum and human milk feeding practices to 6 months: a prospective cohort study with vulnerable women in Toronto, Canada.

OBJECTIVES: To examine whether use of expressed human milk in the first two weeks postpartum is associated with cessation of human milk feeding and non-exclusive human milk feeding up to 6 months. DESIGN: Pooled data from two prospective cohort studies SETTING: Three Canada Prenatal Nutrition Program (CPNP) sites serving vulnerable families in Toronto, Canada. PARTICIPANTS: 337 registered CPNP clients enrolled prenatally from 2017 to 2020; 315 (93%) were retained to 6 months postpartum. EXCLUSIONS: pregnancy loss or participation in prior related study; Study B: preterm birth (<34 weeks); plan to move outside Toronto; not intending to feed human milk; hospitalisation of mother or baby at 2 weeks postpartum. PRIMARY AND SECONDARY OUTCOME MEASURES: Main exposure variable: any use of expressed human milk at 2 weeks postpartum. OUTCOMES: cessation of human milk feeding by 6 months; non-exclusive human milk feeding to 4 months and 6 months postpartum. RESULTS: All participants initiated human milk feeding and 80% continued for 6 months. Exclusive human milk feeding was practiced postdischarge to 4 months by 28% and to 6 months by 16%. At 2 weeks postpartum, 34% reported use of expressed human milk. Any use of expressed human milk at 2 weeks was associated with cessation of human milk feeding before 6 months postpartum (aOR 2.66; 95% CI 1.41 to 5.05) and with non-exclusive human milk feeding to 4 months (aOR 2.19; 95% CI 1.16 to 4.14) and 6 months (aOR 3.65; 95% CI 1.50 to 8.84). TRIAL REGISTRATION NUMBERS: NCT03400605, NCT03589963.

Dietary diversity and social determinants of nutrition among late adolescent girls in rural Pakistan.

The conditions in which adolescent girls mature shape their health, development and nutrition. Nutrient requirements increase to support growth during adolescence, but gaps between consumption and requirements exist in low- and middle-income countries. We aimed to identify and quantify the relationship between dietary intake and diverse social determinants of nutrition (SDN) among a subset of adolescent girls 15-18.9 years (n = 390) enrolled within the Matiari emPowerment and Preconception Supplementation (MaPPS) Trial. The primary outcome, dietary diversity score (DDS), was derived by applying the Minimum Dietary Diversity for Women 10-item scale to 24-h dietary recall data collected three times per participant. To examine the associations between the SDN-related explanatory variables and DDS, we generated a hierarchical, causal model using mixed effects linear regression to account for the cluster-randomized trial design. Using all data, diets lacked diversity (DDS mean ± SD: 3.35 ± 1.03 [range: 1-7; n = 1170]), and the minimum cut-off for dietary diversity was infrequently achieved (13.5%; 95% CI: 11.6-15.6%). Consumption of starches was reported in all recalls, but micronutrient-rich food consumption was less common. Of the SDN considered, wealth quintile had the strongest association with DDS (P < 0.0001). The diets of the sampled Pakistani adolescent girls were insufficient to meet micronutrient requirements. Poverty was the most important predictor of a diet lacking in diversity, indicating limited purchasing power or access to nutritious foods. Dietary diversification and nutrition education strategies alone are unlikely to lead to improved diets without steps to tackle this barrier, for example, through fortification of staple foods and provision of supplements.

High levels of breastmilk feeding despite a low rate of exclusive breastfeeding for 6 months in a cohort of vulnerable women in Toronto, Canada.

Exclusive breastfeeding (EBF) for 6 months is a global public health goal, but measuring its achievement as a marker of population breastmilk feeding practices is insufficient. Additional measures are needed to understand variation in non-EBF practices and inform intervention priorities. We collected infant feeding data prospectively at seven time points to 6 months post-partum from a cohort of vulnerable women (n = 151) registered at two Canada Prenatal Nutrition Program sites in Toronto, Canada. Four categories of breastmilk feeding intensity were defined. Descriptive analyses included the (i) proportion of participants in each feeding category by time point, (ii) use of formula and non-formula supplements to breastmilk, (iii) proportion of participants practising EBF continuously for at least 3 months; and (iv) frequency of transitions between feeding categories. All participants initiated breastmilk feeding with 70% continuing for 6 months. Only 18% practised EBF for 6 months, but 48% did so for at least 3 continuous months. The proportion in the EBF category was highest from 2 to 4 months post-partum. Supplemental formula use was highest in the first 3 months; early introduction of solids and non-formula fluids further compromised EBF at 5 and 6 months post-partum. Most participants (75%) transitioned between categories of breastmilk feeding intensity, with 35% making two or more transitions. Our data show high levels of breastmilk provision despite a low rate of EBF for 6 months. Inclusion of similar analyses in future prospective studies is recommended to provide more nuanced reporting of breastmilk feeding practices and guide intervention designs.

Characteristics of vulnerable women and their association with participation in a Canada Prenatal Nutrition Program site in Toronto, Canada. / Caractéristiques de femmes vulnérables en lien avec leur participation aux activités d'un centre du Programme canadien de nutrition prénatale à Toronto (Canada).

INTRODUCTION: The Canada Prenatal Nutrition Program (CPNP) supports community organizations to provide maternal-infant health services for socially/economically vulnerable women. As part of our research program exploring opportunities to provide postnatal breastfeeding support through the CPNP, we investigated the sociodemographic and psychosocial characteristics of clients enrolled in a Toronto CPNP site and explored associations with participation. METHODS: Data were collected retrospectively from the charts of 339 women registered in one southwest Toronto CPNP site from 2013 to 2016. Multivariable regression analyses were used to assess associations between 10 maternal characteristics and three dimensions of prenatal program participation: initiation (gestational age at enrolment in weeks), intensity (number of times one-on-one supports were received) and duration (number of visits). RESULTS: The mean (SD) age of clients was 31 (5.7) years; 80% were born outside of Canada; 29% were single; and 65% had household incomes below the Statistics Canada family size-adjusted low-income cut-offs. Income was the only characteristic associated with all dimensions of participation. Compared to clients living above the low-income cut-off, those living below the low-income cut-off enrolled in the program 2.85 weeks earlier (95% CI: -5.55 to -0.16), had 1.29 times higher number of one-on-one supports (95% CI: 1.03 to 1.61) and had 1.29 times higher number of program visits (95% CI: 1.02 to 1.63). CONCLUSION: Our findings show that this CPNP site serves vulnerable women, with few differences in participation based on maternal characteristics. This evidence can guide service provision and monitoring decisions at this program site. Further research is needed to explore new program delivery models to enhance perinatal services for vulnerable women.

Effect on breastfeeding practices of providing in-home lactation support to vulnerable women through the Canada Prenatal Nutrition Program: protocol for a pre/post intervention study.

BACKGROUND: Only one-third of Canadian infants are exclusively breastfed for the first 6 months of life as recommended. Skilled lactation support in the early postpartum period is one strategy for improving breastfeeding outcomes by building breastfeeding self-efficacy and resolving difficulties. Access to such support is limited among vulnerable women, including those who are new immigrants, low income, under-educated, young or single. The Canada Prenatal Nutrition Program (CPNP) aims to improve birth and breastfeeding outcomes among vulnerable women, but currently lacks a formal framework for providing postpartum lactation support. METHODS: This pre/post intervention study will examine the effect on breastfeeding outcomes of an evidence-based in-home lactation support intervention provided through the CPNP. We will enrol 210 pregnant women who intend to breastfeed and are registered CPNP clients at two sites in Toronto, Canada. During the intervention phase, postpartum home visits by International Board Certified Lactation Consultants (IBCLCs) will be pro-actively offered to registered clients of the two sites. Double-electric breast pumps will also be provided to those who meet specific criteria. Infant feeding data will be collected prospectively at seven time points from 2 weeks to 6 months postpartum. Descriptive and regression analyses will be conducted to measure intervention effects. The primary outcome is exclusive breastfeeding at 4 months postpartum. Secondary outcomes include the duration of any and exclusive breastfeeding, timing of introduction of breastmilk substitutes and timing of introduction of solid foods. Breastfeeding self-efficacy will be assessed prenatally and at 2 weeks and 2 months postpartum. Other measures include maternal socio-demographics, infant feeding intentions, maternal depression and anxiety, and household food insecurity. Monitoring data will be used to assess the reach, uptake and fidelity of intervention delivery. DISCUSSION: Increasing access to skilled lactation support through the CPNP may be an effective means of improving breastfeeding practices among vulnerable women and thereby enhancing health and development outcomes for their infants. This pre/post intervention study will contribute evidence on both the effectiveness and feasibility of this approach, in order to guide the development and further testing of appropriate models of integrating lactation support into the CPNP. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03589963 ) registered July 18, 2018.

Variation in Human Milk Composition Is Related to Differences in Milk and Infant Fecal Microbial Communities.

Previously published data from our group and others demonstrate that human milk oligosaccharide (HMOs), as well as milk and infant fecal microbial profiles, vary by geography. However, little is known about the geographical variation of other milk-borne factors, such as lactose and protein, as well as the associations among these factors and microbial community structures in milk and infant feces. Here, we characterized and contrasted concentrations of milk-borne lactose, protein, and HMOs, and examined their associations with milk and infant fecal microbiomes in samples collected in 11 geographically diverse sites. Although geographical site was strongly associated with milk and infant fecal microbiomes, both sample types assorted into a smaller number of community state types based on shared microbial profiles. Similar to HMOs, concentrations of lactose and protein also varied by geography. Concentrations of HMOs, lactose, and protein were associated with differences in the microbial community structures of milk and infant feces and in the abundance of specific taxa. Taken together, these data suggest that the composition of human milk, even when produced by relatively healthy women, differs based on geographical boundaries and that concentrations of HMOs, lactose, and protein in milk are related to variation in milk and infant fecal microbial communities.

Comparison of Two Approaches for the Metataxonomic Analysis of the Human Milk Microbiome.

Recent work has demonstrated the existence of large inter-individual and inter-population variability in the microbiota of human milk from healthy women living across variable geographical and socio-cultural settings. However, no studies have evaluated the impact that variable sequencing approaches targeting different 16S rRNA variable regions may have on the human milk microbiota profiling results. This hampers our ability to make meaningful comparisons across studies. In this context, the main purpose of the present study was to re-process and re-sequence the microbiome in a large set of human milk samples (n = 412) collected from healthy women living at diverse international sites (Spain, Sweden, Peru, United States, Ethiopia, Gambia, Ghana and Kenya), by targeting a different 16S rRNA variable region and reaching a larger sequencing depth. Despite some differences between the results obtained from both sequencing approaches were notable (especially regarding alpha and beta diversities and Proteobacteria representation), results indicate that both sequencing approaches revealed a relatively consistent microbiota configurations in the studied cohorts. Our data expand upon the milk microbiota results we previously reported from the INSPIRE cohort and provide, for the first time across globally diverse populations, evidence of the impact that different DNA processing and sequencing approaches have on the microbiota profiles obtained for human milk samples. Overall, our results corroborate some similarities regarding the microbial communities previously reported for the INSPIRE cohort, but some differences were also detected. Understanding the impact of different sequencing approaches on human milk microbiota profiles is essential to enable meaningful comparisons across studies. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT02670278.

Key genetic variants associated with variation of milk oligosaccharides from diverse human populations.

Human milk oligosaccharides (HMO), the third most abundant component of human milk, are thought to be important contributors to infant health. Studies have provided evidence that geography, stage of lactation, and Lewis and secretor blood groups are associated with HMO profile. However, little is known about how variation across the genome may influence HMO composition among women in various populations. In this study, we performed genome-wide association analyses of 395 women from 8 countries to identify genetic regions associated with 19 different HMO. Our data support FUT2 as the most significantly associated (P < 4.23-9 to P < 4.5-70) gene with seven HMO and provide evidence of balancing selection for FUT2. Although polymorphisms in FUT3 were also associated with variation in lacto-N-fucopentaose II and difucosyllacto-N-tetrose, we found little evidence of selection on FUT3. To our knowledge, this is the first report of the use of genome-wide association analyses on HMO.

Breastfeeding rates are high in a prenatal community support program targeting vulnerable women and offering enhanced postnatal lactation support: a prospective cohort study.

BACKGROUND: In Canada, 91% of all mothers initiate breastfeeding, but 40-50% stop by 6 months and only 34% breastfeed exclusively for 6 months, with lower rates among socially and/or economically vulnerable women. The Canada Prenatal Nutrition Program (CPNP) aims to support breastfeeding among vulnerable women, but there is no formal framework or funding for sites to integrate proactive postnatal breastfeeding support. This research aimed to i) describe infant feeding practices among clients of one Toronto CPNP site using charitable funds to offer a lactation support program (in-home lactation consultant visits, breast pumps); ii) determine whether breastfeeding outcomes at 6 months differ based on maternal sociodemographics and food insecurity; and iii) assess utilization of the lactation support program. METHODS: Infant feeding practices were collected prospectively at 2 weeks, 2, 4 and 6 months postpartum via telephone questionnaires (n = 199). Maternal sociodemographics were collected at 2 weeks and food insecurity data at 6 months postpartum. Program monitoring records were used to determine utilization of the lactation support program. RESULTS: Ninety-one percent of participants were born outside of Canada; 55% had incomes below the Low-Income Cut-Off; and 55% reported food insecurity. All participants initiated breastfeeding, 84% continued for 6 months and 16% exclusively breastfed for 6 months. Among breastfed infants, ≥76% received vitamin D supplementation. Approximately 50% of infants were introduced to solids before 6 months. Only high school education or less and food insecurity were associated with lower breastfeeding rates. Overall, 75% of participants received at least one visit with a lactation consultant and 95% of these received a breast pump. CONCLUSIONS: This study provides initial evidence that postnatal lactation support can be delivered within a CPNP site, with high uptake by clients. While all participants initiated breastfeeding and 84% continued for 6 months, adherence to the recommended 6 months of exclusive breastfeeding was low. Further research is needed to better understand the barriers to exclusive breastfeeding and how to support this practice among vulnerable women. Study registered at clinicaltrials.gov as NCT03400605 .

Gaps and priorities in assessment of food environments for children and adolescents in low- and middle-income countries.

School-aged children and adolescents have complex interactions with their food environments-the point of engagement of individuals with the food system-and are influenced by a diversity of individual, household and organizational factors. Although a wide range of methods have been proposed to define, monitor and evaluate food environments, few are tailored to school-aged children and adolescents. Here, we interrogate published literature on food metrics and methodologies for the characterization of food environments for school-aged children and adolescents living in low- and middle-income counties. We identify key priority actions and potential indicators for better monitoring and evaluation to galvanize policymaking to improve the healthiness of these interactions, which are so crucial to future adult well-being.

Premasticated food transfer by wild chimpanzee mothers with their infants: Effects of maternal parity, infant age and sex, and food properties.

Premasticated food transfer, when an individual partially breaks down food through chewing and feeds it to another individual, usually mouth-to-mouth, is described widely across human cultures. This behavior plays an important role in modern humans' strategy of complementary feeding, which involves supplementing maternal milk in infant diets with processed, easily digestible versions of adult foods. The extent to which other primates engage in premasticated food transfer with infants is unclear, as premasticated food transfers have been only occasionally reported in other ape species. We investigated premasticated food transfers in 62 mother-infant pairs of wild chimpanzees at Ngogo, Uganda, as well as unresisted food taking, when mothers passively allow infants to seize food. We evaluated the presence or absence and rates of premasticated food transfer and unresisted food taking relative to maternal parity and infant age and sex and assessed the food species and part used. We found that chimpanzee mothers regularly shared premasticated food with their infants aged between 6 months and 4 years, but they were more likely to share, and more frequently shared, with younger infants. The frequency with which females shared premasticated food may relate to maternal experience, as multiparous females shared premasticated food more often than did first-time mothers, which we did not find with unresisted food taking. Both easy-to-chew, commonly eaten foods and tougher, rarely eaten foods were shared. Premasticated food transfer and unresisted food taking may be infant-rearing strategies to facilitate the transition from a diet of exclusive maternal milk to solid food during early infancy. Premasticated food transfer in particular may provide energetic, immune, or growth benefits to infants through reduced chewing effort and maternal saliva. Given our findings in chimpanzees and earlier reports in other ape species, we suggest that the foundation of complementary feeding, a uniquely hominin strategy, might have been present in a common ancestor shared with the other great apes in the form of premasticated, mouth-to-mouth food transfer by mothers with their offspring.

Corrigendum: What's Normal? Microbiomes in Human Milk and Infant Feces Are Related to Each Other but Vary Geographically: The INSPIRE Study.

[This corrects the article DOI: 10.3389/fnut.2019.00045.].

Multipathogen Analysis of IgA and IgG Antigen Specificity for Selected Pathogens in Milk Produced by Women From Diverse Geographical Regions: The INSPIRE Study.

Breastfeeding provides defense against infectious disease during early life. The mechanisms underlying this protection are complex but likely include the vast array of immune cells and components, such as immunoglobulins, in milk. Simply characterizing the concentrations of these bioactives, however, provides only limited information regarding their potential relationships with disease risk in the recipient infant. Rather, understanding pathogen and antigen specificity profiles of milk-borne immunoglobulins might lead to a more complete understanding of how maternal immunity impacts infant health and wellbeing. Milk produced by women living in 11 geographically dispersed populations was applied to a protein microarray containing antigens from 16 pathogens, including diarrheagenic E. coli, Shigella spp., Salmonella enterica serovar Typhi, Staphylococcus aureus, Streptococcus pneumoniae, Mycobacterium tuberculosis and other pathogens of global health concern, and specific IgA and IgG binding was measured. Our analysis identified novel disease-specific antigen responses and suggests that some IgA and IgG responses vary substantially within and among populations. Patterns of antibody reactivity analyzed by principal component analysis and differential reactivity analysis were associated with either lower-to-middle-income countries (LMICs) or high-income countries (HICs). Antibody levels were generally higher in LMICs than HICs, particularly for Shigella and diarrheagenic E. coli antigens, although sets of S. aureus, S. pneumoniae, and some M. tuberculosis antigens were more reactive in HICs. Differential responses were typically specific to canonical immunodominant antigens, but a set of nondifferential but highly reactive antibodies were specific to antigens possibly universally recognized by antibodies in human milk. This approach provides a promising means to understand how breastfeeding and human milk protect (or do not protect) infants from environmentally relevant pathogens. Furthermore, this approach might lead to interventions to boost population-specific immunity in at-risk breastfeeding mothers and their infants.

The Lived Experience of Global Public Health Practice: A Phenomenological Account of Women Graduate Students.

There is a dearth of research that aims to understand graduate students' lived experience of global health practice. Difficulties, distress, and trauma occur before and after these students' placement abroad, and they often increase when returning home. Moreover, few articles address the increased vulnerabilities faced by women, such as sexual violence and gender-based discrimination. We conducted a phenomenological study to understand the lived experience of Canadian and US women graduate students participating in global public health practice. Eight participants participated in 21 in-depth interviews, while 17 participants created 35 lived experience descriptions through a guided writing exercise. Our findings reveal participants' underlying discomfort with privilege while conducting fieldwork abroad, as well as depressive feelings once they return home. According to participants, while their global health fieldwork challenged previous ways of thinking and being, limited spaces and avenues for openly sharing these processes contributed to mental health challenges. Participants reported that these interviews were their first opportunity to fully share their global health experiences. Based on our analysis of these shared experiences, we argue that academic institutions participating in global health should provide appropriate and accessible resources, adequate financial compensation, safe spaces for authentic conversations, and time for processing experiences throughout the research cycle and especially in the months and years following fieldwork.