Molecular and serological detection of occult hepatitis B virus among healthy  hepatitis B surface antigen-negative blood donors in Malaysia.

Shuaibu A Hudu, Nabil S Harmal, Mohammed I Saeed, Ahmad S Alshrari, Yasmin A Malik, Mohd T Niazlin1, Roshida Hassan, Zamberi Sekawi
1. Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences,
Universiti Putra Malaysia
2. Medical Microbiology and Parasitology, Faculty of Basic Medical Sciences, College of Health Sciences,
Usmanu Danfodiyo University Sokoto, 840232 Sokoto State, Nigeria
3. Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
4. Department of Clinical Science, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman,
Malaysia
5. National Blood Centre Malaysia, Jalan Tun Razak Kuala Lumpur, 504000 Malaysia
6. Department of Basic Health Sciences, Faculty of Pharmacy,Northern Border Universiti, 91911 Rafha,Saudi Arabia

Abstract
Background:Occult hepatitis B infections are becoming a major global threat, but the available data on its prevalence in various  parts of the world are often divergent.

Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface antigen-negative serum using anti-HBc as  a marker of previous infection.

Patient and methods: A total of 1000 randomly selected hepatitis B surface antigen-negative sera from blood donors were  tested for hepatitis B core antibody and hepatitis B surface antibody using an ELISA and nested polymerase chain reaction was  done using primers specific to the surface gene (S-gene).

Results: Of the 1000 samples 55 (5.5%) were found to be reactive, of which 87.3% (48/55) were positive for hepatitis B surface antibody, indicating immunity as a result of previous infection however, that does not exclude active infection with escaped  mutant HBV. Nested PCR results showed the presence of hepatitis B viral DNA in all the 55 samples that were positive for core  protein, which is in agreement with the hepatitis B surface antibody result.

Conclusion:This study reveals the 5.5% prevalence of occult hepatitis B among Malaysian blood donors as well as the reliability of using hepatitis B core antibody in screening for occult hepatitis B infection in low endemic, low socioeconomic settings.

Keywords:Hepatitis B, surface antigen, core antibody, polymerase chain reaction, occult hepatitis B infection