Prevalence of occult hepatitis B virus infection among blood donors in Ulaanbaatar city, 2013 / Монголын Анагаах Ухаан

ABSTRACT

remains the most frequent transfusion-transmitted viral infection; thus, the term occulthepatitis B virus infection (OBI) was introduced. OBI is simply defined as serologically undetectable hepatitis Bsurface antigen (HBsAg-ve), despite the presence of circulating HBV DNA with or without the presence of HBVantibodies.GoalTo determine the prevalence of occult hepatitis B among blood donors and evaluate the presence of HBV DNAin HBsAg negative plasma samples.Materials and MethodsIt includes 16700 samples which donated in NCTM in Ulaanbaatar in 2013. We used to “triplex” PCR assay thatincluded the detect of hepatitis B virus HBV-DNA in addition HCV-RNA and HIV1/2-RNA for whom with absenceof serological markers of infection. The studies used molecular biology methods were performed with the help ofequipment (ROCHE COBAS S 201) and technology based on Real Time PCR (pool size 6 donation) Then wechoose HBsAg negative, DNA positive samples and determined, anti-HBc and anti-HBs by serological methods,of ELISA Wantai HBc and HBs 3.0 tests.ResultsThe 14948 samples were detected serological negative in the total of 16700 samples. PCR test results show 35(0.23%) positive by HBV-DNA 29 (82.9%) of the 35 DNA positive blood donors were alone anti-HBc positive and3 (8.6 %) were anti-HBs, anti-HBc positive. 7(17.1%) were seronegative. Of the 35 OBI cases, 28 (80%) weredetected the first time they were screened for HBV DNA while 7 (20%) gave one more HBV PCR-nonreactiveresults before detection. Callback studies we determined 2 cases were pre-HBsAg window period.Conclusion:The prevalence of HBV DNA positive in HBsAg negative blood donors is found 0.2%. HBV NAT needs eitherextreme sensitivity or to be performed on individual donations to eliminate HBV DNA-containing units.