Occult Hepatitis B Virus Infection among Blood Donors; North Middle Libya

Background: Post transfusion hepatitis B (PTHB) continues to be an important public health concern in regard to blood transfusion in Libya. The inclusion of tests specifically for the hepatitis B surface antigen (HBsAg) began as part of the mandatory screening of blood donors in the early 1980s. This endeavor significantly enhanced blood safety in terms of protecting people against the transmission of an HBV infection. However, several studies have revealed that a percentage of HBsAg donors who tested negative may in fact still be positive for the illness due to a presence of different antigens known as hepatitis B core antibodies (anti-HBc) meaning that it constitutes a possibility of circulating hepatitis B viral DNA (HBV-DNA), thus being a potential source of post transfusion hepatitis B (PTHB).

Objectives: To determine the presence of anti-HBc and HBV-DNA in healthy HBsAg negative blood donors in the middle northern region of Libya (composed of the metropolitan cities of Misrata, Khoums, Zlitin, Sirite and surrounding small villages).

Methods: The Misrata central blood bank (which services the middle northern region of Libya) provided A total of 979 HBsAg negative blood samples from healthy blood donors that were tested for anti-HBc using the VITROS® 3600 Immunodiagnostic System. The reactive samples were then further tested for the presence of HBV-DNA.

Results: From the sample of 979, 38 of whom (3.9%) were anti-HBc positive. One sample tested positive for HBV-DNA by PCR (polymers chain reaction) from the anti-HBc positive samples indicating (2.6%) of the subgroup of anti-HBc positive samples and 0.1% from the whole sample population screened.

Conclusion: Despite blood donors being HBsAg-negative in the middle northern region of Libya, 3.9% had anti-HBc, of which 2.6% of the anti-HBc positive donors had detectable HBV DNA. Further studies are needed to determine the actual yield of including an anti-HBc test in routine screening of blood donors.