Reducing the risk of hepatitis B virus transfusion-transmitted infection

Abstract

Before 1970, approximately 6% of multi-transfused recipients acquired a transfusion-transmitted Hepatitis B virus (HBV) infection. The safety improvements since then have been tremendous. From a level of a few infections per 1000 donations, the risk today, depending on the screening algorithm and additional measurements performed, has decreased to around 1:500,000 to 1:1,000,000, an improvement greater than 1000-fold compared to 50 years ago. This enormous gain in safety has been achieved through many factors, including development of increasingly more sensitive Hepatitis B antigen (HBsAg) assays; the adoption in some countries of hepatitis B core antibody (anti-HBc) screening; an improved donor selection procedure; HBV vaccination programs; and finally the introduction of HBV nucleic acid testing (NAT). Because there is a tendency in transfusion medicine to add one safety measure on top of another to approach the ultimate goal of zero risks, costs become increasingly a matter of debate. It is obvious that any new measure in addition to existing methods or measures will have very poor cost effectiveness. Therefore each country needs to perform its own calculation based on the country’s own epidemiology, resources, political and public awareness of the risks, in order to choose the correct and most cost-efficient measures. Ideally, each country would make decisions regarding implementation of additional blood safety measures in the context of both the perceived benefit and the allocation of overall health care resources.

Hepatitis B and C infection: Is it a problem in Polish healthcare workers?

“…The study group comprised: 260 (50%) nurses, 50 (9.6%) surgical medical staff, 45 (8.6%) ward attendants, 54 (10.4%) nonsurgical medical staff, 57 (11%) dental personnel, 25 Detecting anti-HCV, HBsAg, anti-HBs and anti-HBcT was performed by enzyme immunoassays (ECLIA, Roche) according to the manufacturer's instruction. Anti-HBs concentration equal to or greater than 10 IU/l was considered positive.…”

“…There are a few possibilities explaining the anti-HBcT alone status. It can be a falsepositive result, a late acute resolving infection with undetectable HBsAg but with persistence of low level of HBV DNA for a short time, a chronic carrier state with HBsAg levels below the detection limit of current assays or HBV infection with a virus carrying mutations resulting in undetectable HBsAg [25]. Some studies show that prevalence of HBV-DNA is higher in anti-HBcT alone positive cases than in both anti-HBcT and anti-HBs positive samples [26].…”

Three-Year Experience in NAT Screening of Blood Donors for Transfusion Transmitted Viruses in Croatia

“…For HCV, the rates of NAT are lower in northern countries (Switzerland 0.45 per million donations and Ireland 0.00 per million donations) than in Mediterranean countries (Spain 2.15 per million and Greece 5.97 per million. Countries with low HBV endemism, such as Germany, Switzerland, New Zealand, the US and Canada, reported HBV NAT yields of up to 1: 730,000 [20][21][22][23][24], whereas countries with moderate endemism such as Poland and some Mediterranean countries reported figures up to 1: 51,987 [25][26][27]. The HBV NAT incidence rate of 1 per 10,900 donations in Croatia is comparable to the HBV incidence rate of 1: 15,600 HBV positive donations in Slovenia.…”

Effects of Risk Factors on Anti-HBs Development in Hepatitis B Vaccinated and Nonvaccinated Populations

“…Thus, one can anticipate that there could be other reasons that have impaired the development of anti-HBs or made anti-HBs undetectable. It is thought that anti-HBs remains undetectable in the laboratory tests because of binding to the large amount of HBsAg present in the blood as well as binding to immune complexes (19). However, the association of anti-HBs development in a HBVexposed population (anti-HBc positive) has not yet been investigated.…”