Debunking claims: COVID-19 vaccines do not harm bifidobacteria in breastfed infants

A viral social media claim asserts that breastfeeding infants of mothers vaccinated against COVID-19 lack bifidobacteria in their gut. This claim, attributed to a doctor's interview, has been widely circulated online.

However, multiple scientific studies contradict this assertion. Research published in 2023 observed 49 lactating women vaccinated with Pfizer's COVID-19 vaccine. The study found no change in the bifidobacteria levels in their breast milk. Furthermore, the study noted a temporary increase in antibodies that protect the infant, suggesting a potential benefit rather than harm.

Another study from Cambridge scientists in 2024 investigated the broader impact of COVID-19 vaccines on human gut microflora. Analyzing fecal samples from various individuals, including those with weakened immune systems, they found that the gut microflora remained stable after vaccination. No significant reduction in beneficial bacteria, including bifidobacteria, was observed.

Crucially, the Cambridge study highlighted that the COVID-19 virus itself, rather than the vaccine, is responsible for disrupting gut microflora and reducing beneficial bacteria like bifidobacteria. Bifidobacteria are vital for infant gut health, aiding digestion and immune system development.

These findings collectively debunk the social media claim, indicating that COVID-19 vaccines do not harm beneficial gut bacteria in breastfed infants and that the virus poses a greater risk to gut health.