Hi Dr Leong, I believed I was infected in Sep 21 during Delta. I didn't know but I was sick for about 10 days with fever for a couple of days and when it cleared up I began to heal. It was relatively mild for me as I quarantine myself for 2 weeks at home without seeing a doctor hence not in MOH data. I am a blood test volunteer with NCID for the covid study and my serology results from 18/01/2022 shows that antibodies against SARS-CoV-2 viruses were detected. SARS-CoV-2 sVNT (Genscript): 55.44%, Positive. My question is as an unvaxed person who is now tested with natural antibodies of 55% as indicated above, do I need to go through primary vaccine or do I need just booster shot? I have not fallen ill since sep 21 and I do not have any co-modality as I live a healthy lifestyle.