Couldn't have said it better myself. A couple of years back my two step sons both got whooping cough despite being "fully" vaccinated. One had a nasty lingering cough for 3-4 months. Evenmy vaccinated husband got a mild cough which was probably whooping cough. Myself and my son are not vaccinated for whooping cough, and neither of us caught it at all. When we questions the doctors as to why the vaccinated kids caught it, we were told the most common strain of whooping cough around at the moment is not covered at all by the vaccination, and therefore the vaccinated kids actually had no immunity to it. It's possible that at some stage I had this strain of whooping cough and developed immunity to it which I passed on to my son through my breastmilk...