Elecsys® Anti-HBs II

Immunoassay for the quantitative determination of antibodies to hepatitis B surface antigen (HBsAg)

Elecsys® Anti-HBs II

Immunoassay for the quantitative determination of antibodies to hepatitis B surface antigen (HBsAg)

Hepatitis B is a potentially life threatening liver infection caused by the hepatitis B virus (HBV). It is transmitted through contact with the blood or other body fluids of an infected person.1 The disease is not always self limiting: In adults approx. 5 % of acute infections will follow a chronic course of varying degrees of severity; infants will develop chronic hepatitis B in up to 90 % of the cases.1

An estimated 257 million people are living with HBV infection. In 2015, hepatitis B resulted in 887,000 deaths, mostly from complications (including cirrhosis and hepatocellular carcinoma).1 Anti-HBs is an antibody that is directed against the hepatitis B surface antigen.2,3 Anti-HBs can be detected several weeks after the disappearance of hepatitis B surface antigen (HBsAg).4,5

Anti-HBs can be formed following a hepatitis B infection or after hepatitis B vaccination.4,5 Antibodies are formed against to HBsAg immunodeterminant “a” determinant region, which is common to all subtypes, and against subtype-specific determinants.2,6,7

Anti-HBs tests are used within the scope of hepatitis B vaccination to check the necessity and success of vaccination.3,5,8 In addition, Anti-HBs tests are used to monitor the course of disease following acute hepatitis B infection.4

Elecsys® Anti-HBs II

Elecsys® Anti-HBs II

  • Systems

    cobas e 411 analyzer, cobas e 601 / cobas e 602 modules, cobas e 801 module

  • Testing Time

    18 minutes

  • Test principle

    Double antigen sandwich assay

  • Calibration


  • Interpretation

    <10 IU/L = non-reactive
    ≥10 IU/L = reactive

  • Traceability

    First World Health Organization (WHO) Reference Standard 1977

  • Sample material

    Serum collected using standard sampling tubes or tubes containing separating gel. K2-EDTA and K3-EDTA plasma.

  • Sample volume

    40 μL cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    24 μL cobas e 801 module

  • Onboard stability

    8 weeks cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    16 weeks cobas e 801 module

  • Intermediate precision in positive samples

    cobas e 411 analyzer: CV 4.8 – 8.3 %
    cobas e 601 / cobas e 602 modules: CV 3.4 – 6.8 %
    cobas e 801 module: CV 3.6 – 6.9 %

  • Relative sensitivity

    100 % (n = 296, vaccinated)
    100 % (n = 373, recovered from HBV infection)

  • Relative specificity

    99.78 % (n = 2,673, blood donors)
    99.45 % (n = 1,623, routine samples)



  1. WHO. Hepatitis B Fact sheet. Available at: https://www.who.int/news-room/fact-sheets/detail/hepatitis-b accessed November 2020
  2. Seeger, C., Zoulim, F., Mason, W.S. (2007). Hepadnaviruses. In: Field’s Virology, Knipe DM, Howley RM (eds), 5th edition, Lippincott Williams and Wilkins, Philadelphia, USA. Chapter 76, 2977-3029.
  3. WHO (2009). Hepatitis B vaccines. Wkly Epidemiol Rec 84, 405-419.
  4. Liaw, Y.F., Chu, C.M. (2009). Hepatitis B virus infection. Lancet 373, 582-592.
  5. Caspari, G., Gerlick, W.H. (2007). The serologic markers of hepatitis B virus infection – proper selection and standardized interpretation. Clin Lab 53, 335-343.
  6. Kramvis, A., Kew, M., François, G. (2005). Hepatitis B virus genotypes. Vaccine 23, 2409-2423.
  7. Michel, M.L., Tiollais, P. (2010). Hepatitis B vaccines: protective efficacy and therapeutic potential. Pathol Biol (Paris) 58, 288-295.
  8. Elgouhari, H.M., Abu-Rajab Tamini, T.I., Carey, W. (2008). Hepatitis B virus infection: understanding its epidemiology, course, and diagnosis. Cleve Clin J Med 75, 881-889.