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

Background and ObjectivesScreening 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 Methods117,454 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. ResultsConfirmed 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. ConclusionThe 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. HIGHLIGHTSO_LIApulia is the second Italian region with the highest number of Transfusion-Transmitted Infections (TTI) among blood donors; C_LIO_LIIn 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; C_LIO_LIBlood 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. C_LI