Nucleic acid testing for virus screening in Polish blood donors

Dear Sir In reference to the articles published in the December 2002 issue of Transfusion Medicine, we would like to present the current status of nucleic acid testing (NAT) in Poland. Poland is a country with over 38 million inhabitants. One million donations per year are collected by the Blood Transfusion Service (BTS), which functions as part of the public health system. Within BTS, we distinguish 21 regional blood transfusion centres and the National Centre for Transfusion Medicine at the Institute of Haematology and Blood Transfusion (IHBT). In 2000, the hepatitis C virus (HCV) RNA NAT testing of plasma for fractionation was introduced. Since January 2002, all donations are tested for HCV RNA or for HCVcoreAg (Ortho Diag). In our preliminary study, we found that HCVcoreAg is a good alternative for NAT because all NAT-positive donations were also HCVcoreAg positive (Brojer et al., 2001). However, later it was shown that a majority, although not all, HCV RNA-positive donations are detectable with this test (Nubling et al., 2002). Current requirements are that plasma for fractionation (CPMP, 1998) is tested with NAT only. Therefore, according to our procedures, blood components can be released after negative result of HCVcoreAg or HCV RNA, but all plasma for fractionation must be tested by NAT. HCVcoreAg is used mainly in emergency, when NAT results would delay the release of platelet concentrates or when faced with any logistic difficulties (delivering plasma samples to NAT laboratories). NAT is performed in plasma pools of 48 donations prepared by Genesis Robotic Sample Processor 200 (Tecan,Switzerland),PMS(Tecan,Hannover,Germany). For HCV RNA isolation and detection, the commercial test Cobas Amplicor v 2 0/Cobas Ampliscreen v 2 0 in the presence of internal control is used. In each run, positive control (100 IUmL 1 HCV RNA WHO Standard) is tested. With this method, NAT is performed in eight molecular biology laboratories in regional blood transfusion centres of Rzeszów, Bydgoszcz, Kalisz, Racibórz, Gdańsk, Białystok, Poznań and Warsaw. In February 2003, two additional laboratories (Szczecin, Lublin) introduced NAT for HIV and HCV detection in individual donations by CHIRON TMA HIV-1/HCV Assay. The reference molecular biology laboratory is located at IHBT. According to the regulations of Polish Blood Transfusion Service (Sabliński & ętowska, 2000), each molecular biology laboratory must obtain three certificates before starting NAT. These confirm (i) adequate organization of the laboratory (checked by auditors from the reference laboratory); (ii) adequate skills of personnel: the exam is passed at IHBT and a 2-day training in the IHBT is obligatory (every year); (iii) correct results of standardization of methods. The certificate must be verified every year. The standardization programme meets the requirements of the Paul Ehrich Institute for the pooling process, identification of positive donations (5000 IU HCV RNA/mL) and adequate test sensitivity. Permanent monitoring of NAT results by the IHBT is also performed. Each laboratory is obliged to report the frequency of positive donations, false reactive results and invalid runs (Table 1). Each positive donation is confirmed at IHBT by testing of plasma samples from donation bag. The follow-up programme for HCV RNA positive/anti-HCV negative blood donors is introduced (The follow-up programme is supported by grant No. 3 PO5D 028 23 from the Polish Committee for Scientific Research). Until now, mini-pool testing was performed on 2,242,016 donations, 38 of which were HCV RNA positive/anti-HCV negative (0 0017%). Twenty-two were available for follow-up, and in 18, anti-HCV was detected; the remaining four were still anti-HCV negative 2–8 weeks after the HCV RNA detection. 44 873 donations have been tested by CHIRON TMA HIV-1/HCV Assay and no ‘window’ donation was identified. However, HCV RNA was detected in 26 anti-HCV positive donors. As compared to other European countries and the United States, in Poland, a relatively higher frequency of HCV ‘window period’ donations has been observed (Eglin, 2002; Jarvis & Simmonds, 2002; Correspondence: E. Brojer, Department of Immunohaematology, 957 Warsaw, Chocimska 5, Poland. Tel. : þ48 849 36 51x144; fax: þ48 22 849 69 52/848 89 70; e-mail: ebrojer@ihit.waw. pl Transfusion Medicine, 2004, 14, 79–80