Comparison of SARS-CoV-2-Specific Antibodies in Human Milk after mRNA-Based COVID-19 Vaccination and Infection
Hannah G. Juncker,
Sien J. Mulleners,
Marit J. van Gils,
Tom P. L. Bijl,
Christianne J. M. de Groot,
Dasja Pajkrt,
Aniko Korosi,
Johannes B. van Goudoever,
Britt J. van Keulen
Affiliations
Hannah G. Juncker
Department of Pediatrics, Emma Children’s Hospital, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
Sien J. Mulleners
Department of Pediatrics, Emma Children’s Hospital, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
Marit J. van Gils
Department of Medical Microbiology and Infection Prevention, Amsterdam Infection and Immunity Institute, University of Amsterdam, Amsterdam UMC, 1105 AZ Amsterdam, The Netherlands
Tom P. L. Bijl
Department of Medical Microbiology and Infection Prevention, Amsterdam Infection and Immunity Institute, University of Amsterdam, Amsterdam UMC, 1105 AZ Amsterdam, The Netherlands
Christianne J. M. de Groot
Department of Obstetrics and Gynaecology, Amsterdam Reproduction & Development Research Institute, Vrije Universiteit, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
Dasja Pajkrt
Department of Pediatrics, Emma Children’s Hospital, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
Aniko Korosi
Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
Johannes B. van Goudoever
Department of Pediatrics, Emma Children’s Hospital, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
Britt J. van Keulen
Department of Pediatrics, Emma Children’s Hospital, Amsterdam Reproduction & Development Research Institute, Amsterdam UMC, 1081 HV Amsterdam, The Netherlands
SARS-CoV-2-specific antibodies are secreted into human milk of infected or vaccinated lactating women and might provide protection to the breastfed infant against COVID-19. Differences in antibody response after these types of exposure are unknown. In this longitudinal cohort study, we compared the antibody response in human milk following SARS-CoV-2 vaccination or infection. We analyzed 448 human milk samples of 28 lactating women vaccinated with the SARS-CoV-2 vaccine BNT162b2 as well as 82 human milk samples of 18 lactating women with a prior SARS-CoV-2 infection. The levels of SARS-CoV-2-specific IgA in human milk were determined over a period of 70 days both after vaccination and infection. The amount of SARS-CoV-2-specific IgA in human milk was similar after SARS-CoV-2 vaccination and infection. After infection, the variability in IgA levels was higher than after vaccination. Two participants with detectable IgA prior to vaccination were analyzed separately and showed higher IgA levels following vaccination compared to both groups. In conclusion, breastfed infants of mothers who have been vaccinated with the BNT162b2 vaccine receive human milk with similar amounts of SARS-CoV-2-specific antibodies compared to infants of previously infected mothers.
