The transmission of viral and non-viral infectious pathogens continues to be the most serious of the potential adverse effects of allogenic tissue transplantations. EU Directive 2006/17/EC stipulates that cadaveric blood specimens for serology testing in the context of post-mortem tissue donation must be taken not later than 24 h post-mortem. An expanded time slot would significantly improve the availability of tissue donations, but there are no significant data on the stability of infectious serology assays for anti-human immunodeficiency virus (HIV), anti-hepatitis C virus (HCV), hepatitis B virus (HBV) surface antigen (HBsAg) and anti-HBC core antigen (HBc) in samples collected more than 24 h post-mortem. In this prospective study, serum samples of 30 deceased persons were taken upon admission to the Institute of Forensic Medicine (University Hospital Hamburg-Eppendorf, Germany) and at 12, 24, 36 and 48 h post-mortem. All samples were measured twice, first using the Abbott AxSYM system, and then after ~9 months of storage at -70 °C using the BEP III System with Siemens and Ortho reagents. For HIV, six deceased persons with a pre-mortem HIV history were included. All samples (at committal and at 12, 24, 36, 48 h) were reactive. Indeterminate or false-negative results did not occur. For HCV, 17 deceased persons with a pre-mortem HCV history were included; 16 samples were reactive up to 48 h and one was reactive at 36 h post-mortem (48 h sample was not available). Indeterminate or false-negative results did not occur. For HBV, nine deceased persons were included: five samples were initially positive for HBsAg and remained positive up to 48 h, and eight of the samples were reactive for anti-HBc up to 48 h and one up to 36 h post-mortem (48 h sample was not available). Indeterminate or false-negative results did not occur. These data suggest that infectious serological testing may be extended for blood samples of potential tissue donors collected up to 48 h post-mortem to detect antibodies or antigens for HIV, HBV and HCV.