Exclusive breastfeeding strengthens babies' immunity against COVID-19

A new study carried out by researchers from the National Institute of Women, Children and Adolescents Health Fernandes Figueira (IFF/Fiocruz) highlights the benefits of exclusive breastfeeding in strengthening babies' immunity against COVID-19. The research, which involved women vaccinated against the virus, revealed that human milk contains significant levels of neutralizing antibodies, especially among mothers who breastfeed exclusively.

The study by IFF/Fiocruz researchers Yasmin Amaral, Antonio Egídio Nardi, Daniele Marano, Ana Carolina da Costa, and Maria Elisabeth Moreira reveals that mothers vaccinated against COVID-19 who exclusively breastfeed their babies transfer higher levels of neutralizing antibodies to human milk, protecting their children against Sars-CoV-2 infections. "The results represent a major breakthrough in understanding passive immunity transferred through breastfeeding and reinforce the recommendation of this practice, exclusively, in the first six months of life," says pediatrician and research lead Maria Elisabeth.

Results

The study, which analyzed a sample of women vaccinated with two or more doses of different COVID-19 vaccine technologies, revealed that mothers who breastfeed exclusively. had 22.6% neutralizing antibodies in their milk, compared to 16.1% of those who do not breastfeed exclusively. The discovery is relevant because, in Brazil, vaccination of babies under six months is not yet available, which makes breastfeeding a crucial tool for protecting children.

"The neutralizing antibodies present in human milk are a natural and effective defense against the virus, and exclusive breastfeeding enhances this protection. As the pandemic continues to evolve, it is essential that mothers follow breastfeeding guidelines to ensure the safety of their babies. The study confirms the vital role of breastfeeding in the transfer of passive immunity, and we are strengthening the scientific evidence that the vaccine has a positive impact on the protection not only of mothers, but also of babies," emphasizes Maria Elisabeth Moreira.

The researchers point out that the technology of the vaccines (mRNA, Inactivated Virus, or Non-Replicating Viral Vector) did not influence the amount of neutralizing antibodies present in human milk, indicating that, regardless of the type of vaccine received, breastfeeding remains an essential practice to protect babies against COVID-19.

With the publication of this research, IFF/Fiocruz contributes to the scientific debate on passive immunity transferred by human milk, highlighting the importance of exclusive breastfeeding as an essential practice for protecting babies against COVID-19. The study provides valuable data that can influence public health policies and help strengthen campaigns to encourage breastfeeding. The importance of immunizing mothers and exclusive breastfeeding has never been clearer than now, highlighting a safe and effective way to protect babies.