[Residual risk for transfusion-transmitted hepatitis B virus infection due to occult hepatitis B virus infection in donors living in Yaoundé, Cameroon].

Introduction: viral infection caused by hepatitis B virus is the most frequent transfusion-transmitted viral infection. Although the search for hepatitis B surface antigen (HBsAg) in blood banks has significantly reduced the risk for transfusion-transmitted virus infection, there is still a residual transfusion risk of transmission from donors with occult hepatitis B. Blood bags containing aHBc with or without aHBs and viral DNA can cause infections and represent a threat to transfusion safety when aHBc levels are undetectable. The purpose of this study is to determine the residual risk for transfusion-transmitted hepatitis B virus at the Central Hospital of Yaoundé (CHY) as well as at the St Martin de Porres's Catholic Hospital (SMPCH) in Yaoundé, Cameroon.

Methods: we conducted a cross-sectional study among blood donors at the Central Hospital of Yaoundé (CHY) and the St Martin de Porres's Catholic Hospital. In these subjects the search for aHBc and/or the aHBs was conducted by immunochromatography. HBV DNA test was performed on blood samples tested positive for aHBc and/or aHBs by Polymerase Chain Reaction (PCR) technique using specific primers.

Results: out of a total of 193 blood donors negative for HIV, HBV (HBsAg), HCV serological markers and treponema infections, the overall seroprevalence of aHBc and/or aHBs was 9,84% (19/193). Out of a total of 19 potentially infected donors, HBV DNA was detected in 03 individuals, including 02 aHBc carriers and 01 carrier of both aHBc and aHBs, reflecting a prevalence of occult hepatitis B of 15,79% (3/19) [IC 95% =3,38%-39,58%] and a residual risk for transfusion-transmitted hepatitis B virus of 1,55% (3/193) [IC 95% =0,32%-4,48%].

Conclusion: this study shows that the residual risk for transfusion-transmitted hepatitis B virus is low. However, it is recommended to screan blood donors for aHBc and/or aHBs.