hmm... less than 10% is not that big a number lah. Anyway, the jab is to intro a small amt of virus into ur body mah so that u can build immunity to it. So it all depends on how ur body reacts to it lor.
Drs and nurses seldom explain all these things also. I just lucky i got one that is so cheong hei...kekeke... but good lah, at least she got explain alot of things