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Children Vaccine

Mom to baby transmission of antibodies

We are seeing more and more evidence that moms pass COVID19 antibodies to their babies…

There have been 3 important studies that have recently come out telling the same story…

  1. Between April and August 2020, scientists tested 1,500 women who gave birth in Philadelphia. They found…
    -83 had COVID antibodies
    -Among the 83, 87% of their babies tested positive for IgG antibodies (the long lasting antibodies) after they were born
    -Transferring antibodies was not different among infants born to mothers with asymptomatic or symptomatic illness
    -In 25% of the babies, their antibody levels were 1.5 to 2 times higher than the mother’s concentration
    -The longer the time period between the start of a pregnant woman’s COVID infection and her delivery, the more antibodies were transferred to the baby
  2. From April 4 to July 3, 2020, in a single university hospital in Denmark, 1,313 women took part in a study.
    -28 women (2.1%) had antibodies against COVID
    -67% of newborns delivered by mothers with antibodies had COVID IgG antibodies.
    -Neonatal outcomes (like birth weight, APGAR value, amniotic fluid, CPAP, and blood pH) were not affected by the antibody status of the mother
  3. Another study enrolled 22 COVID+ moms and 34 COVID- negative moms and tested their cord blood after birth.
    -Antibody transfer was efficient after second-trimester infection
    -While antibodies do pass, they do less efficiently than the antibodies produced after vaccination for flu and whooping cough. But this effect was only observed in third-trimester infection.

Like always, we still have a lot of unanswered questions. We need more research to better understand two things:

  1. Do vaccine-generated antibodies behave comparably to antibodies from COVID infection?
  2. Are antibodies protective against newborn infection? If so, at what concentration?

Bottom line: We already know there are benefits to pregnant women getting vaccinated. These studies suggest that there also may be benefits to the baby. Interestingly, timing of infection (or possibly timing of vaccination) may be important to ensure baby getting antibodies.

Unfortunately, pregnant women were excluded from clinical trials (which has stirred quite the debate among scientists), so these questions will take quite a bit of time to answer.

Love, YLE

Data Sources:
https://jamanetwork.com/journals/jamapediatrics/fullarticle/2775945
https://journals.lww.com/greenjournal/Fulltext/2021/01000/Severe_Acute_Respiratory_Syndrome_Coronavirus_2.7.aspx
https://www.cell.com/cell/fulltext/S0092-8674(20)31749-9