{"id":"hbsag","name":"Hepatitis B Surface Antigen (HBsAg)","shortName":"HBsAg","aliases":["Hepatitis B Surface Antigen","HBsAg","Hep B Surface Ag","HBs Antigen","HBs Ag","Hep B sAg","Australia antigen","Hepatitis B Surface Antigen Screen","Hepatitis B Virus Surface Antigen","HBsAg Screen","HBsAg, Qualitative","Hepatitis B Surface Antigen with Reflex Confirmation","HBsAg with Reflex Confirmation","HBs Antigen Scrn","Hep B Surface Antigen","Hepatitis B Surface Ag","HBV surface antigen"],"abbreviations":["HBsAg","HBs Ag"],"loinc":[{"code":"5196-1","primary":true},{"code":"5195-3","primary":false},{"code":"7905-3","primary":false}],"specimen":"serum-or-plasma","units":[],"referenceRanges":[],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"A protein from the hepatitis B virus. A positive result is linked to the virus being in your blood now, from a recent infection or a long-term one.","url":"https://bloodtesttracker.com/markers/hbsag","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}