Study Detected mRNA in 45% of Lactating Women - Dr John Campbell -JAMA

Study Detected mRNA in 45% of Lactating Women.
- Dr John Campbell -JAMA

JAMA -
https://jamanetwork.com/journals/jamapediatrics/fullarticle/2796427

https://www.youtube.com/watch?v=1uF1oPyh8OY

Detection of Messenger RNA COVID-19 Vaccines in Human Breast Milk

https://jamanetwork.com/journals/jamapediatrics/fullarticle/2796427

JAMA Pediatrics

(September 26, 2022)

Initial messenger RNA (mRNA) vaccine clinical trials excluded several vulnerable groups,

young children and lactating individuals

Current FDA website, re children over 6 months

https://www.fda.gov/news-events/press...

Today, the U.S. Food and Drug Administration authorized emergency use of the Moderna COVID-19 Vaccine,

and the Pfizer-BioNTech COVID-19 Vaccine,

for the prevention of COVID-19 to include use in children down to 6 months of age.
From the JAMA paper

The US Food and Drug Administration deferred the decision to authorize COVID-19 mRNA vaccines for infants younger than 6 months,

until more data are available,

because of the potential priming of the children’s immune responses that may alter their immunity

The Centers for Disease Control and Prevention, re breast feeding mothers

https://www.cdc.gov/coronavirus/2019-...

COVID-19 vaccination is recommended for all people 6 months and older. This includes people who are pregnant, breastfeeding, trying to get pregnant now, or might become pregnant in the future.

Back to the JAMA study

The Centers for Disease Control and Prevention recommends offering the COVID-19 mRNA vaccines to breastfeeding individuals

although the possible passage of vaccine mRNAs in breast milk resulting in infants’ exposure at younger than 6 months was not investigated.

This study investigated whether the COVID-19 vaccine mRNA can be detected in the expressed breast milk (EBM) of lactating individuals

receiving the vaccination within 6 months after delivery.

N =11

Moderna mRNA-1273 vaccine (n = 5)

Pfizer BNT162b2 vaccine (n = 6)

Samples of EBM were collected before vaccination (control),

and for 5 days postvaccination.

131 EBM samples were collected

(1 hour to 5 days after vaccine administration)

The presence of COVID-19 vaccine mRNA in different milk fractions

assayed using 2-step quantitative reverse transcriptase–polymerase chain reaction.

Results

Trace amounts of BNT162b2 and mRNA-1273 COVID-19 mRNA vaccines were detected in 7 samples from 5 different participants,

at various times up to 45 hours postvaccination

No vaccine mRNA was detected in prevaccination

Discussion

The sporadic presence and trace quantities of COVID-19 vaccine mRNA detected in EBM suggest that breastfeeding after COVID-19 mRNA vaccination is safe,

particularly beyond 48 hours after vaccination.

These data demonstrate for the first time the biodistribution of COVID-19 vaccine mRNA to mammary cells,

and the potential ability of tissue EVs to package the vaccine mRNA that can be transported to distant cells.

In rats

https://www.sciencedirect.com/science...

Up to 3 days following intramuscular administration,

low vaccine mRNA levels were detected in the heart, lung, testis, and brain tissues, indicating tissue biodistribution

Vaccine administration -- lipid nanoparticles containing the vaccine mRNA --- mammary glands (hematogenous and/or lymphatic routes)

Vaccine mRNA released into mammary cell cytosol -- recruited into developing EVs ---- secreted in EBM

Caution is warranted about breastfeeding children younger than 6 months in the first 48 hours after maternal vaccination until more safety studies are conducted.