the quantity of the virus is useless, you can have no virus at all but many infected cells which can create new virus from a dna template of the virus inside the cells, hbsag can reflect more or less the number of this dna template
usless wrong and old test which is not quantitative.if it is sold as quantitative it is a fraud, quantitative has a unit iu/ml for quantity and it reflects quantity of infected cells/immune response