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Advice please - hep b immunity and window

Hi,
I had the hep b vaccine 13 yrs ago. Can't remember if it was the full course or time frames injections were given.
On my blood test it showed I have Hep B surface antibodies of 15 mIU/ mL in April and 11 mIU/mL in May. The test says a level if over 10 is considered protective if full course was given.
The doctor said 15 or 11 might not be enough to avoid infection. Is this right?

Surface antigen is negative at 1, 5, and 11 weeks after possible exposure.
Surface antibody is 15 at 1 wk post possible exposure, 11 at 5 weeks.
Core antibody is negative at 11 wks (not listed on earlier test results)

According to Dr Hook on this forum and CDC 1-9 wks should be enough for surface antigen test. But then some people say you have to wait 6 mths.
If surf antigen hasn't shown up yet, can I still test positive at some point?
I also had a booster shot at 10 wks- will this affect my results or window period?

Any clarification or help would be much appreciated.
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Avatar universal
Thanks stef2011.  I've been told that the hep b vaccine can wear off over time and it's effectiveness and ability to last depends if the series was administered in the correct time frames.  Apparently different people react to the vaccine in different ways as well (eg some don't build immunity as well as others)

I was just concerned as my levels were quite low and it was so long ago that I did the course, and I'm not sure the three injections were spaced correctly.

I more want to know that if the HbSurface antigen was negative at 1,4,5 and 11 wks whether this is enough time for it not to go positive.
The CDC 'range' for hbsag is 1-9 weeks, normally showing positive at 4 weeks, but I'm not sure if 9 wks is the latest possible.

Dr E Hook said in a couple of posts that 2 mths is long enough to allow to test positive for surface antigen, but in another one he said 3 mth test result is definitive.

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Avatar universal
you cant get hbv after being vaccinated even if hbsag goes very low, adults dont get chronic hbv even wthout vaccine (4% chronicity only)

just have 3 shots of hbv vaccine again
Helpful - 0
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