O exame anti hbs é solicitado para verificar se a pessoa possui imunidade contra o vírus da hepatite B, seja ela adquirida por meio da vacinação ou através da cura da doença. Governments require this to ensure people dont come into the country with contagious diseases, addictions or other health problems that would endanger or burden the public. HBsAg is present in most chronically infected Anti-HBs indicates resolving or past infection or successful immunization with vaccine and confers protective immunity.
Direct antibody sandwich enzyme immunoassay- utilizes polystyrene microwells coated in native HBsAg as solid phase and conjugate with horseradish peroxidase-labeled HBsAg. The pathogens are tested by serological kits based on enzyme-linked immunosorbent assay (ELISA), chemiluminescence (CLIA) and eletrochemiluminescence (ECLIA). It is one of several various causes of hepatitis, a condition characterized by inflammation and enlargement of the test detects antibodies in the blood that are produced by the immune system in response to a hepatitis A infection.