Anti-HBs Antibody Levels and Anti-HBc Detection Among HBV-Vaccinated Freshmen Enrolled in the Department of Laboratory Sciences, Shiraz University of Medical Sciences, Iran

Abstract

Background: There are few studies indicating the post-neonatal HBV vaccination level of anti-HBs antibody in first-year enrolled university students in Iran. In addition, anti- HBc antibody detection, which is a good indicator of virus exposure, has not been reported in vaccines. Hence, this study was conducted to determine the level of anti-HBs and anti-HBc antibodies in the serum sample of medical laboratory students who had received primary infantile HBV vaccination. Methods: This study was conducted on first-year students enrolled in the department of laboratory sciences at Shiraz University of Medical Sciences, Iran. For determining anti-HBs and anti-HBc titers, 5 mL of venous blood was aseptically collected. Anti-HBs and anti-HBc antibody levels were determined by enzyme-linked immunosorbent assay. HBV DNA was also performed on DNA extracted from individuals positive for an anti-HBc antibody test. Results: Of the 257 vaccinated individuals (188 females and 69 males) who participated in this study, 36.2% showed a non-protective anti-HBs response (anti-HBs < 10 mIU/mL) and 164/257 individuals (63.8%) showed a protective anti-HBs response (anti-HBs ≥ 10 mIU/mL). Significant numbers of females had protective levels of anti-HBS antibody in serum samples in comparison with the males (P < 0.001). Anti-HBc antibody was detected in 3 participants; however, HBsAg was not detected in any of the cases. HBV DNA was found in two. Conclusions: Our results indicate that a substantial number of our study population vaccinated against HBV during childhood showed non-protective anti-HBs antibody level. Therefore, a booster dose of vaccine needs to be scheduled for students with anti-HBs level < 10 mIU/mL prior to the start laboratory internship.