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New study vaccine and immunosuppressants

my little penguin

Staff member

So some response just 1/3 of a nonsuppressed person

Lynda Lynda

So should I get a third dose or the "booster?"

My first jab was in April 2021 and second jab was May 2021. Moderna.

I made an appt for a third dose this Saturday.
San Diego
The "booster" and the "3rd dose" are exactly the same in terms of what is being injected. Where they differ is in who is receiving the injection.

"Boosters" are for healthy people in order to boost up their immune response and thus increase the concentration of anti-COVID antibodies in the blood that may have slowly waned over time. "Third doses" are for patients suffering from some medical condition or receiving some drug(s) that have the effect of weakening the immune response, and thus they may have mounted a poor response in the first place to the first two injections.

I'm getting my 3rd dose this afternoon after work.


Staff member
New York, USA
To give some reference numbers - to show how the body responds to the shots and booster/3rd shot -

I received my 2nd shot 3/15 - here are my antibody levels..

4/13 - over 250 U/ml
6/15 - 451.0 U/ml
9/30 - 188.0 U/ml

Received my 3rd shot/booster on 9/30 AFTER the blood draw above -
10/15 - 1426.0

So the 3rd shot definitely did 'something' - it will be interesting to see how levels change as time goes on - I will be getting bloods drawn again at 1, 3, 6 and 12 months out.....


Staff member
There is a difference between the third shot and booster for Moderna recipients. The doses are different. A third shot, for an immunocompromised person, is exactly the same as the first and second shots in terms of dose - 100 micrograms. The booster that has just been authorized is half that - 50 micrograms and is for those populations that are eligible for a booster (65+ etc).

my little penguin

Staff member
Ds got his results back
Cov2IGG quantitative test through labcorp and university of North Carolina ibd PREVENT. Study
After 2 shots —92
After 3 shots —148
Anything above 1 is considered positive for antibodies
Anything over 30 is considered very high
He was outside their reference range high both times