It does for certain bugs/substances, doesn't it, though?
I checked my tetanus antibodies(actually anti-neurotoxin antibodies) recently and they were 5 times over what's considered adequate and I haven't had (at that point) a booster shot in over 20 years.
I checked my tetanus antibodies(actually anti-neurotoxin antibodies) recently and they were 5 times over what's considered adequate and I haven't had (at that point) a booster shot in over 20 years.