Introduction: Occupational infection of clinical health care workers with blood-borne viruses (BBVs) like human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV) is a current and often emotionally discussed issue. HCV and especially HIV are still stigmatized. The consequence is a broad and maybe irrational fear of professional health care workers being infected occupationally. Therefore, we assessed preoperative screening to: (1) answer whether this can detect not previously diagnosed blood-borne virus infections to a great extent, (2) calculate a cost-benefit ratio to find out, if the screening's potential ability to prevent occupational transmission of BBVs to health care workers faces unjustifiable high costs. Hypothesis: Preoperative routine screening is limited suitable for enhancement of detecting fomites compared to interview the patient. Material(s) and Method(s): Retrospective cohort study of preoperative screening for HIV, HBV and HCV (HBsAg, anti-HCV and HIV-Ab/Ag-Combination) for every patient who was admitted to the traumatologic department for elective arthroplasty between 01/01/1997 and 31/12/2008. Result(s): Among the 1534 patients who underwent elective prosthetic surgery [total hip (879) and knee arthroplasty (508), followed by shoulder, elbow and upper ankle joint], 693 (45.2%) patients were male and 841 (54.8) female. Mean age was 64.2 +/- 13.8 years. Screening tests were available for 1373 patients (89.5%). Among all screened patients, we found 21 HCV, 10 HBV and 1 HIV infections. 5 HBV (0.5%) and 7 HCV infections (0.7%) were unknown before. Every newly detected infectious patient occasions screening costs about 7250 . Considering this data, the risk of HCV transmission from an index patient with unknown status of infectiousness to health care worker after percutaneous contact to blood is 0.08 and of HIV transmission is 0.00054 in our study population. Discussion(s): Routine preoperative screening for BBVs of patients undergoing elective arthroplasty, who were asked for HBV, HCV and HIV, should be reconsidered and is, in times of sparse funds, overpriced. Level of Evidence: IV. Copyright © 2016 Elsevier Masson SAS.