From the profile strips,it was positive, but using the first strips it was negative, what causes this?.
Rapid kit testing procedures are non confirmatory. When this happen, go for a sophisticated and confirmatory testing procedure, at the instance of your physician!
Due to formation of complexes of HbsAg and HbsAb, they are not detectable after some time of initial infection,this phase is called window phase.
Since core Antigen is in core of virus where Core antibody can’t reach, HbcAb titre is very high and is detectable even in window phase and after recovery as well.
That’s why HbcAb is positve but HbsAg and HbsAb is not detectable