Transfusion-transmitted infections among blood donors in South-East Italy: Contribution of blood transfusion centres for territory-based surveillance

Background and Objectives Screening for Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), Human Immunodeficiency Virus (HIV) infections and Syphilis in blood donors is important to evaluate both risk of transfusion-transmitted infections (TTIs) and their current prevalence in apparently healthy individuals. Apulia (South-East Italy) resulted to be one of the two Italian regions with the highest TTI cases. Screening tests results of blood donors were analysed, with the purpose to provide updated information on the epidemiology of TTIs. Materials and Methods 117,454 donors referring to blood transfusion centres of the North Apulia between 2019-2022 were analysed; serum samples underwent analysis for TTIs by chemiluminescent-immunoassay and nucleic-acid-amplification tests. Results Confirmed reactivities were: 47 HBV (0.04%), 19 HCV (0.02%), 1 HIV (0.001%), and 42 Syphilis (0.04%), respectively. Of 47 HBV-infected donors, 28 were Hepatitis B surface Antigen (HBsAg) positive, including 8 with HBV-DNA positive, and 19 HBsAg negative but with detectable viraemia, identifying the presence of occult B infection (OBI). A higher number of positive cases resulted in the age group 51-65 (34 HBV, 12 HCV, 1 HIV and 25 Syphilis) and over 65 (4 HBV, 5 HCV, 0 HIV and 2 Syphilis) (p-value<0.05). Occasional donors showed higher frequency of TTIs compared to regular donors. Conclusion The study shows consistent number of undiagnosed TTIs among blood donors, and the importance of transfusion centres for territory-based surveillance that can contribute to the detection of novel TTI cases among asymptomatic people, helping the diagnosis of submerged infectious diseases that are still a global threat. HIGHLIGHTS 1. Apulia is the second Italian region with the highest number of Transfusion-Transmitted Infections (TTI) among blood donors; 2. In the period 2019-2022, HBV resulted to be the main TTI detected among blood donors, followed by Syphilis, HCV and HIV in North Apulia; the overall TTIs distribution resulted significantly higher among occasional donors than regular donors; 3. Blood transfusion centres may represent important surveillance points for HBV, HCV, HIV and Syphilis and can contribute to the detection of novel TTI cases in apparently healthy individuals. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ospedali Riuniti di Foggia Ethical committee approved the use of human data. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors