Introduction: Herpes virus type 8 (HHV-8)-related disease has been well described in recipients of solid organ transplantation (SOT). Kaposi’s sarcoma (KS) and other rarer forms of disease are more often associated with reactivation of infection, but severe disease is known to occur following graft-related primary infection. Determinant factors of increased morbidity and mortality in post-transplant primary HHV-8 infection have not been fully elucidated but level of immunosuppression and delayed diagnosis may be contributory factors.    

Methods: Cases of post-transplant HHV-8 disease in SOT recipients which were identified in the UK between 2015 and 2019 were thoroughly examined by the National Health Service Blood and Transplant (NHSBT), which is the responsible organisation for deceased organ donor procurement in the UK. HHV-8 became the commonest donor-derived infection amongst the serious adverse events investigated and a review of the impact of this infection in deceased organ donation in the UK was deemed necessary.  A working group was convened to look at scientific evidence, assess the impact of donor-related HHV-8 infection on recipient outcomes and the feasibility of implementing appropriate interventions. This led to a recommendation by the UK Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO) in 2022 to commence serological HHV-8 screening in deceased organ donation.

Results: Ten events were investigated between 2015 and 2019, with identification of seven clusters involving 23 recipients, including 11 new infections consistent with donor-derived infection. The observed transmission rate in this case series was 48% (11 of 23), with 64% fatality (7 of 11). In accordance with SaBTO recommendations, NHSBT is due to commence a HHV-8 screening program. Serological tests for identification of asymptomatic, infected individuals will be done post-donation in a centralised laboratory. Positive donor result triggers a management process for recipients, for early identification of infection and monitoring for disease manifestation; this will be particularly important for non-malignant forms of KS, KS without skin manifestation and KS of the graft. 

Discussion: With the aim to improve patient outcomes, the focus is on averting deaths due to donor-derived primary HHV-8 infection occurring within 12 months of transplantation. This program predominantly addresses the challenges of deceased organ donation and severe post-transplant primary HHV-8 infection in recipients, but also raises the need for a risk-based assessment option for living donors and transplant recipients, which needs to be addressed by transplant centres based on infection and disease prevalence in their donor and recipient pools. Identification of donor and recipient infection status before disease development should allow monitoring and avoid late diagnosis of disease.  Ongoing monitoring of the program will inform future guidance and practice.