Titres of Antibodies to Hepatitis B Surface Antigen following Hepatitis B Vaccination among Medical Students

Aim: To estimate antibody titres to Hepatitis B surface antigen (HBsAg) among vaccinated medical students.

Study Design: Cross sectional study

Place and Duration of Study: Study was done in the Department of Microbiology, Adichunchanagiri Institute of Medical Sciences, B.G. Nagara between October 2019 to November 2019.

Methodology: Study included 281 medical students who had taken three doses of Hepatitis B vaccination. Informed consent and Institutional Ethical clearance was obtained. Under aseptic precautions, 5 ml of venous blood was collected and serum was separated by centrifugation at 3000 rpm for 5 min. Serum were stored at -200 C. Antibodies to Hepatitis B surface antigen were estimated by Electro Chemiluminescence method (Anti-HBs G2 Elecsys cobas e 100- Roche Diagnostics India Pvt. Ltd.) as per manufacturer’s instruction using quality controls.

Results: In the present study, 98.9% of students had Anti HBs antibody titres >10mIU/ml. Only one (1.1%) student had titre <10mIU/ml. Seventy (77.8%) students had antibody titres >1000 mIU/ml and 15 (16.7%) had antibody levels >100≤1000 mIU/ml. Higher seroconversion rates were noted among female students (100%) but was not statistically significant (P value=0.34)

Conclusion: Except for one, all other study participants were found to have protective antibody titres. Vaccination cards containing the vaccination details and the antibody titres should be made available to all medical students to guide infection control practices in case of accidental exposure.