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Antibody numbers for vaccine

my little penguin

Staff member
Predictors of vaccine response were found using a multivariate ordinal logistic regression model with stepwise variable selection. Vaccine response was separated into no response (<50 IU/mL), partial response (50–250 IU/mL), and clinically relevant response >250 IU/mL). P < 0.1 determined if a variable was included in the model.
thus 1 µg/mL = 11.4 IU/mL
Conversion needed

Ds levels were tested in.µg/mL for his study nc study Which is why they seemed so low vs other studies tested in IU/ml units but were marked as high on the results

In his case 1687 IU/ml after 3 shots ( it was 3 months after 3 shot when levels were taken.)
Waiting for blood draw instructions again since he got the booster (4th shot) in Jan

my little penguin

Staff member
We were concerned at first given his numbers were 148 mu g /ml and only saw high numbers as in international IU/ml in reports
This is the first paper found that offers a conversion factor 😀


Staff member
New York, USA

I just looked at my past results (going to get a blood draw next week probably)...

11/21 - 18 ug/mL (high) = 205.2 IU.mL
5/21 - 23 ug/mL (high) = 262.2 IU.mL