PURSUING EPIDEMIOLOGICAL INVESTIGATION OF CASES OF POSSIBLE HBV OR HCV INFECTION OF THE RECIPIENT WITH TRANSFUSIONS OF DONOR BLOOD COMPONENTS
Authors: Romanova T. Yu , Tupoleva T. A , Tikhomirov Dmitry S. , Yaroslavtseva N. G , Ignatova E. N , Gulyaeva A. A , Starkova O. G , Gaponova T. V 
Published: April 2021

Background. Nosocomial transmission of HBV and HCV is often believed to be associated with transfusion of inapparent infection blood. Nevertheless, recently both promotion of voluntary (fee free) donorship and the evolution of laboratory screening, including the introduction of high-sensitivity tests, have significantly reduced the transfusion-associated complications, including infectious ones. The incidence ratae of primary transfusion-transmitted infections in patients with hematological malignancies remains to be high. A lot of publications are devoted to epidemiological studies on the determination of the source of infection with parenteral viral hepatitis by virtue of molecular analysis of viral strains, which is one of the important tools for obtaining objective data on the presence or absence of epidemiological relationship in the investigation of iatrogenic cases of infection. However, there is still no clear algorithm for pursuing epidemiological investigations of such cases. The aim of this study was to develop the procedure for the epidemiological investigation of probable transfusion-transmitted HBV and HCV infection with the use of Laboratory Information System and Transfusiology Information System software in patients with hematological malignancies. Material and methods. 6 cases of primary HBV and 3 cases of primary HCV were registered in patients with hematological malignancies in the National Medical Research Center for Hematology. All patients had a history of blood transfusions. A two-steps procedure for the epidemiological investigation was developed. 5 epidemiological investigations were held according to this procedure. 35 archival blood samples (7 from patients and 28 from blood donors) were tested for serological and/or molecular markers of HBV and HCV to fulfill this. Results. First step of procedure includes the determination of the date of initial infection (IID). IID is an earliest point of maximal likelihood of the detection of viral markers by laboratory techniques. This value is calculated on the basis of the results of a comprehensive virological examination of the recipient. The second step includes a history of blood transfusions from IID up to date of initial detection of primary infection evaluation. Then the analysis of donor-recipient pairs should be executed for the detection of probable sources of infection. As the result of study 5 epidemiological investigations were held in accordance to the developed procedure and the Laboratory Information System and Transfusiology Information System software. Two of the five investigations cannot be completed because of donors’ rejection to undergo a follow-up examination. In other cases infection transmission through the blood transfusion was excluded. Conclusion. A standard operating procedure of epidemiological investigation of HBV or HCV transmission has been developed and implemented. In order to reveal the latent forms of these infections a protocol of viral screening in patients with hematological malignancies at the admission to hematology ward was also developed and implemented.