Survival of Vaccine-Induced Human Milk SARS-CoV-2 IgG, IgA and SIgA Immunoglobulins across Simulated Human Infant Gastrointestinal Digestion.

Breastfeeding can be a vital way of acquiring passive immunity via the transfer of antibodies from the mother to the breastfeeding infant. Recent evidence points to the fact that human milk contains immunoglobulins (Ig) against the SARS-CoV-2 virus, either after natural infection or vaccination, but whether these antibodies can resist enzymatic degradation during digestion in the infant gastrointestinal (GI) tract or indeed protect the consumers remains inconclusive. Herein, we evaluated the levels of IgG, IgA, and secretory IgA (SIgA) antibodies against the spike protein of SARS-CoV-2 in 43 lactating mothers who received at least two doses of either an mRNA-based vaccine (Pfizer/BioNTech, Moderna; n = 34) or an adenovirus-based vaccine (AstraZeneca; n = 9). We also accessed the potential persistence of SARS-CoV-2 IgA, IgG, and secretory IgA (SIgA) antibodies from vaccinated women in the GI tract of the infants by means of a static in vitro digestion protocol. Our data depict that, although slightly reduced, the IgA antibodies produced after vaccination resist both the gastric and intestinal phases of infant digestion, whereas the IgGs are more prone to degradation in both phases of digestion. Additionally, SIgA antibodies were found to greatly resist the gastric phase of digestion albeit showing some reduction during the intestinal phase. The evaluation of the vaccine induced Ig profile of breastmilk, and the extent to which these antibodies can resist digestion in the infant GI tract provide important information about the potential protective role of this form of passive immunity that could help decision making during the COVID-19 pandemic and beyond.

The association of breastfeeding self-efficacy with breastfeeding duration and exclusivity: longitudinal assessment of the predictive validity of the Greek version of the BSES-SF tool.

INTRODUCTION: While breastfeeding self-efficacy (BSES) is an important modifiable determinant of breastfeeding, a structured assessment is not standard practice in Cyprus. We assessed the Greek version of the Breastfeeding Self-Efficacy Scale (BSES-SF), including its predictive validity in terms of Breastfeeding (BF) and Exclusive Breastfeeding (EBF) up to the sixth month. METHODS: A methodological study with longitudinal design among 586 mother-infant dyads, as part of the "BrEaST Start in Life" project. BSES was assessed 24-48 h after birth and at the first month. Breastfeeding status was assessed at the clinic, the 1st, 4th and 6th month. The association between BSES and breastfeeding was estimated in logistic regression models and its diagnostic ability in ROC analysis. RESULTS: With Mean = 3.55 (SD = 0.85), BSES was moderate, and lower among Cypriot women, primiparas and those who delivered by Cesarean Section (C/S). There was good internal consistency across the 14 items (Cronbach's α = 0.94) while factor analysis revealed a two-factor structure. BSES scores were higher among mothers who initiated exclusive breastfeeding (M = 3.92, SD = 0.80) compared to breastfeeding not exclusively (M = 3.29, SD = 0.84) and not breastfeeding (M = 3.04, SD = 1.09; p-value < 0.001). There was a stepwise association with exclusivity (40.5% in the highest vs 7.9% lowest quartile of self-efficacy). The association between in-hospital BSES and long-term EBF persisted in multivariable models. Women in the upper quartile of BSES at 48 h were more likely to breastfeed exclusively by adjOR = 5.3 (95% CI 1.7-17.1) at the 1st and adjOR = 13.7 (95% CI 2.7-68.6) at the 4th month. Similar associations were observed between self-efficacy at the 1st month and BF at subsequent time-points. High first month BSES (> 3.96 as per ROC) had 58.9% positive and 79.6% negative predictive value for breastfeeding at 6 months which reflects higher sensitivity but lower specificity. CONCLUSIONS: The Greek version of BSES-SF showed good metric properties (construct, know-group, concurrent and predictive validity). In the absence of community support structures or programmes in Cyprus, prevalence of breastfeeding remains low. This suggests a need for policy, educational and community support interventions, including the systematic use of BSES scale as a screening tool to identify those at higher risk for premature BF discontinuation.

Prevalence of breast-feeding and exclusive breast-feeding at 48 h after birth and up to the sixth month in Cyprus: the BrEaST start in life project.

OBJECTIVE: To assess the prevalence and sociodemographic determinants of breast-feeding (BF) and exclusive breast-feeding (EBF) in Cyprus up to the sixth month. DESIGN: Cross-sectional and longitudinal descriptive study. BF and EBF were estimated based on mothers' self-reported BF status in line with Step 7 of the WHO/UNICEF Baby-Friendly Hospital Initiative questionnaire and based on 24 h recall. SETTING: Maternity wards in all public hospitals and twenty-nine (of thirty-five) private maternity clinics nationwide. SUBJECTS: Consecutive sample of 586 mothers recruited within 48 h from birth, followed up by telephone interview at the first, fourth and sixth month. RESULTS: Although 84·3 % of mothers initiated BF before discharge, prevalence of BF at the sixth month was 32·4 %, with the highest reduction observed between the first and fourth months. Prevalence of EBF at 48 h was 18·8 % and fell gradually to 5·0 % at the sixth month. Mothers with higher educational attainment or higher family income were more likely to breast-feed until the sixth month. In terms of EBF, an association was observed only with education, which persisted until the sixth month. Other than social gradient, mode of delivery was the strongest determinant of BF initiation, exclusivity and continuation. Mothers who gave birth vaginally were three to four times more likely to initiate BF (OR=3·1; 95 % CI 1·7, 5·4) and EBF (OR=4·3; 95 % CI 2·7, 6·8). CONCLUSIONS: The low prevalence of BF and EBF in Cyprus, together with the fact that caesarean section rates are currently among the highest in Europe, suggest the need for further research to understand this multidimensional phenomenon and for interdisciplinary policy action to protect, promote and support BF.