How mRNA COVID-19 vaccines shape immunity in children and breast milk

Longitudinal SARS-CoV-2 mRNA vaccine-induced mucosal, serological, and cellular immunity in children and human milk

NIH-funded research University of California, San Diego · NIH-11146432

This project follows young children, breastfeeding mothers, and their infants to see how mRNA COVID-19 vaccines create immune protection in blood, nasal/saliva tissues, and breast milk.

Quick facts

Grant typeR01 grant
Study typeNIH-funded research
Funding institutionUniversity of California, San Diego NIH-funded
Lab location1 site (La Jolla, United States)
Project IDNIH-11146432 on NIH RePORTER

What this research studies

You would be asked to join a group of about 560 people including children (down to 6 months), lactating mothers, and their infants, plus adults from an existing cohort. Researchers will collect nasal swabs, saliva, blood, and breast milk (if breastfeeding) every three months after vaccination to measure immune responses over time. The team will compare children's immune responses to adults and look at whether antibodies in milk might protect infants. This builds on a cohort started in 2020 and follows participants for several years.

Who could benefit from this research

Good fit: Ideal candidates are children (including those as young as 6 months) receiving mRNA COVID-19 vaccines, lactating mothers and their breastfed infants, and adults enrolled in the existing cohort.

Not a fit: People who are not getting mRNA COVID-19 vaccines, who cannot provide repeated samples, or who live far from the study site may not see direct benefits.

Why it matters

Potential benefit: If successful, the findings could help protect infants and children by guiding vaccine timing and breastfeeding recommendations to boost protection.

How similar studies have performed: Previous adult studies show mRNA vaccines produce antibodies in blood and breast milk, but long-term mucosal and pediatric data remain limited.

Where this research is happening

La Jolla, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.