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.

Developing global guidance on human milk banking.

Donor human milk is recommended by the World Health Organization both for its advantageous nutritional and biological properties when mother's own milk is not available and for its recognized support for lactation and breastfeeding when used appropriately. An increasing number of human milk banks are being established around the world, especially in low- and middle-income countries, to facilitate the collection, processing and distribution of donor human milk. In contrast to other medical products of human origin, however, there are no minimum quality, safety and ethical standards for donor human milk and no coordinating global body to inform national policies. We present the key issues impeding progress in human milk banking, including the lack of clear definitions or registries of products; issues around regulation, quality and safety; and ethical concerns about commercialization and potential exploitation of women. Recognizing that progress in human milk banking is limited by a lack of comparable evidence, we recommend further research in this field to fill the knowledge gaps and provide evidence-based guidance. We also highlight the need for optimal support for mothers to provide their own breastmilk and establish breastfeeding as soon as and wherever possible after birth.

Lorsque la mère est dans l'impossibilité d'allaiter, l'Organisation mondiale de la Santé recommande d'opter pour le lait humain provenant de donneuses, tant pour ses propriétés nutritionnelles et biologiques que pour la contribution avérée qu'il apporte à la lactation et à l'allaitement quand il est utilisé à bon escient. Un nombre croissant de banques de lait humain s'établissent dans le monde entier, en particulier dans les pays à faible et moyen revenu, afin de faciliter la collecte, le traitement et la distribution de lait humain provenant de donneuses. Cependant, contrairement à d'autres produits médicaux d'origine humaine, il n'existe aucune norme minimale de qualité, de sécurité et d'éthique en la matière, et aucun organe de coordination global n'a été créé pour guider les politiques nationales. Dans le présent document, nous évoquons les principaux obstacles à la progression des banques de lait humain, notamment l'absence de définition claire ou de registre de produits; les problèmes relatifs à la réglementation, la qualité et la sécurité; ainsi que les questions éthiques entourant la commercialisation et l'exploitation potentielle des femmes. Jugeant cette progression limitée par le manque de données comparables, nous encourageons à mener d'autres recherches dans ce domaine pour combler les lacunes et fournir des orientations fondées sur des preuves. Nous soulignons également la nécessité d'offrir un soutien optimal aux mères afin qu'elles puissent produire leur propre lait et allaiter autant que possible immédiatement après la naissance.

La Organización Mundial de la Salud recomienda la leche humana donada tanto por sus ventajosas propiedades nutricionales y biológicas cuando no se dispone de la propia leche materna como por su reconocido apoyo a la lactancia y al amamantamiento cuando se utiliza de manera adecuada. Cada vez se crean más bancos de leche humana en todo el mundo, sobre todo en los países de ingresos bajos y medios, para facilitar la recogida, el procesamiento y la distribución de leche humana donada. Sin embargo, a diferencia de lo que ocurre con otros productos médicos de origen humano, no existen estándares mínimos de calidad, seguridad y ética para la leche humana donada ni un organismo mundial de coordinación que sirva de base a las políticas nacionales. En este documento se exponen los principales problemas que impiden el progreso de los bancos de leche humana, como la falta de definiciones claras o de registros de productos; los problemas relacionados con la regulación, la calidad y la seguridad; y las preocupaciones éticas sobre la comercialización y la posible explotación de las mujeres. Dado que el progreso de los bancos de leche humana se ve limitado por la falta de evidencias comparables, se recomienda seguir investigando en este campo para compensar los vacíos de conocimiento y proporcionar una guía asistencial. Asimismo, se destaca la necesidad de apoyar al máximo a las madres para que se provean de su propia leche materna y establezcan la lactancia materna tan pronto y siempre que sea posible después del nacimiento.

Best Practices for Human Milk Collection for COVID-19 Research.

In addition to providing life-giving nutrients and other substances to the breastfed infant, human milk can also represent a vehicle of pathogen transfer. As such, when an infectious disease outbreak, epidemic, or pandemic occurs-particularly when it is associated with a novel pathogen-the question will naturally arise as to whether the pathogen can be transmitted through breastfeeding. Until high-quality data are generated to answer this question, abandonment of breastfeeding due to uncertainty can result. The COVID-19 pandemic, which was in full swing at the time this document was written, is an excellent example of this scenario. During these times of uncertainty, it is critical for investigators conducting research to assess the possible transmission of pathogens through milk, whether by transfer through the mammary gland or contamination from respiratory droplets, skin, breast pumps, and milk containers, and/or close contact between mother and infant. To promote the most rigorous science, it is critical to outline optimal methods for milk collection, handling, storage, and analysis in these situations, and investigators should openly share their methods in published materials. Otherwise, the risks of inconsistent test results from preanalytical and analytical variation, false positives, and false negatives are unacceptably high and the ability to provide public health guidance poor. In this study, we provide "best practices" for collecting human milk samples for COVID-19 research with the intention that this will also be a useful guide for future pandemics.

La pasteurisation à l'aide de la méthode de Holder appliquée au lait maternel provenant de donneuses permet d'inactiver le SRAS-CoV-2.

CONTEXTE: Le recours aux dons de lait maternel pasteurisé est la norme de soins dans les hôpitaux pour les nourrissons ayant un très faible poids à la naissance, afin de faire le pont en attendant que les mères puissent allaiter leur enfant. Le but de cette étude était de vérifier si la pasteurisation à l'aide de la méthode de Holder (à 62,5 °C pendant 30 min) serait suffisante pour inactiver le coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2) dans des échantillons de lait maternel provenant de donneuses. MÉTHODES: Nous avons inoculé avec le SRAS-CoV-2 des échantillons de lait congelés provenant de 10 donneuses de la Rogers Hixon Ontario Human Milk Bank (la banque de lait maternel de l'Ontario) pour atteindre une concentration finale de 1 × 107 DICT50/mL (50 % de la dose infectante de la culture de tissus par mL). Les échantillons ont été pasteurisés à l'aide de la méthode de Holder ou laissés à la température du laboratoire pendant 30 minutes, puis nous avons mis en culture des dilutions en série sur des cellules Vero E6 durant 5 jours. Nous avons utilisé des échantillons témoins dans cette étude, soit des échantillons de lait provenant des mêmes donneuses, auxquels le virus n'a pas été ajouté (échantillons pasteurisés et non pasteurisés), de même que des réplicats de cellules Vero E6 directement inoculées avec le SRAS-CoV-2. Nous rapportons ici les effets cytopathologiques en DICT50/mL. RÉSULTATS: Nous n'avons détecté aucune activité cytopathologique dans l'ensemble des échantillons de lait contenant le SRAS-CoV-2 pasteurisés à l'aide de la méthode de Holder. Dans les échantillons contenant le SRASCoV-2 qui n'ont pas été pasteurisés, mais plutôt laissés à la température du laboratoire pendant 30 minutes, nous avons observé une réduction du titre infectieux d'environ 1 log. INTERPRÉTATION: La pasteurisation du lait maternel à l'aide de la méthode de Holder (à 62,5 °C pendant 30 min) inactive le SRAS-CoV-2. Ainsi, si du lait maternel provenant de donneuses contenait le virus à la suite d'une transmission par la glande mammaire ou d'une contamination, cette méthode de pasteurisation rendrait le lait sans danger pour la consommation par le nourrisson et la manipulation par les travailleurs de la santé.

Holder pasteurization of donated human milk is effective in inactivating SARS-CoV-2.

BACKGROUND: Provision of pasteurized donor human milk, as a bridge to mother's own milk, is the standard of care for very low-birth-weight infants in hospital. The aim of this research was to confirm that Holder pasteurization (62.5°C for 30 min) would be sufficient to inactivate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in donated human milk samples. METHODS: We spiked frozen milk samples from 10 donors to the Rogers Hixon Ontario Human Milk Bank with SARS-CoV-2 to achieve a final concentration of 1 × 107 TCID50/mL (50% of the tissue culture infectivity dose per mL). We pasteurized samples using the Holder method or held them at room temperature for 30 minutes and plated serial dilutions on Vero E6 cells for 5 days. We included comparative controls in the study using milk samples from the same donors without addition of virus (pasteurized and unpasteurized) as well as replicates of Vero E6 cells directly inoculated with SARS-CoV-2. We reported cytopathic effects as TCID50/mL. RESULTS: We detected no cytopathic activity in any of the SARS-CoV-2-spiked milk samples that had been pasteurized using the Holder method. In the SARS-CoV-2-spiked milk samples that were not pasteurized but were kept at room temperature for 30 minutes, we observed a reduction in infectious viral titre of about 1 log. INTERPRETATION: Pasteurization of human milk by the Holder method (62.5°C for 30 min) inactivates SARS-CoV-2. Thus, in the event that donated human milk contains SARS-CoV-2 by transmission through the mammary gland or by contamination, this method of pasteurization renders milk safe for consumption and handling by care providers.

The impact of thermal pasteurization on viral load and detectable live viruses in human milk and other matrices: a rapid review.

Holder pasteurization (62.5 °C, 30 min) of human milk is thought to reduce the risk of transmitting viruses to an infant. Some viruses may be secreted into milk - others may be contaminants. The effect of thermal pasteurization on viruses in human milk has yet to be rigorously reviewed. The objective of this study is to characterize the effect of common pasteurization techniques on viruses in human milk and non-human milk matrices. Databases (MEDLINE, Embase, Web of Science) were searched from inception to April 20th, 2020, for primary research articles assessing the impact of pasteurization on viral load or detection of live virus. Reviews were excluded, as were studies lacking quantitative measurements or those assessing pasteurization as a component of a larger process. Overall, of 65 131 reports identified, 109 studies were included. Pasteurization of human milk at a minimum temperature of 56-60 °C is effective at reducing detectable live virus. In cell culture media or plasma, coronaviruses (e.g., SARS-CoV, SARS-CoV-2, MERS-CoV) are highly susceptible to heating at ≥56 °C. Although pasteurization parameters and matrices reported vary, all viruses studied, except parvoviruses, were susceptible to thermal killing. Future research important for the study of novel viruses should standardize pasteurization protocols and should test inactivation in human milk. Novelty In all matrices, including human milk, pasteurization at 62.5 °C was generally sufficient to reduce surviving viral load by several logs or to below the limit of detection. Holder pasteurization (62.5 °C, 30 min) of human milk should be sufficient to inactivate nonheat resistant viruses, including coronaviruses, if present.