Hi @Intime009,
I am not an expert or a professional in health or science and I too get confused with all the terms and meanings. The Hep B Foundation has the definition of HBsAg as:
Hepatitis B Surface Antigen (HBsAg): The surface protein of the hepatitis B virus that is used as a marker to detect infection. If this blood test is positive, then the hepatitis B virus is present.
This definition is only for qualitative and not quantitative. I think qualitative being negative or positive. I remembered seeing at least one post about HBsAg quantitative. Here are some links to discussions about it. Maybe it can help you until one of the experts can respond and elaborate more.
https://www.hepbcommunity.org/t/deciding-when-to-start-treatment/119/83?u=puallyhbv
https://www.hepbcommunity.org/t/what-is-amount-of-hbsag-loss-per-year-on-taf/1117
https://www.hepbcommunity.org/t/hbsag-count-interpretation/2417/3
Now I am a bit confused as I thought HBsAg qualitative was positive or negative. So now I am at a loss.
https://www.hepbcommunity.org/t/rebound-of-hbsag/2636/10
So this is why we have experts. Hopefully one of them can explain it in a way even I can understand. I wish I could at least get Viral load, HBV DNA and HBsAg quantitative straight. I’d like to add to your question and ask if HBsAg quantitative is a necessary test or good to have done. It seems from what I have been reading in those above links is that it doesn’t change much and it depends what country you reside in and that the U.S. doesn’t even do that test.
Hope this helps you for now,
-Paul