No shot is 100%. The effectiveness is dependent on enough people being immune that the disease cannot spread.
You are right, but that isn’t what happened here.
There were 12 kids out with it in a small school. All were vaccinated. The county health board blamed it on a few kids who did NOT have the vaccine, and who did NOT show any symptoms or diagnoses of whooping cough (Mennonite families). Neither did anyone the non vaccinated kids came in contact with. Typical vaccine effectiveness is around 90%. In this grade school, it was about 50% (half of the class caught it).
They didn’t just say it once, they had public health announcements on the local news about it.
We also had a measles outbreak that followed the same course. Blamed on the non vaccinated kids, who had no symptoms, which got a group of vaccinated kids sick.
Funny thing is a lot of local parents have dropped vaccinations because of it. If I pay for my kid to get their shots, and he gets sick, while the Mennonite kid who didn’t get shots is ok, why am I giving my kid shots?
I am not totally anti vaccine, but I have a growing suspicion that they are not nearly as effective as advertised, and come with some potential of bad side effects.