I expect you'll give me the pure BS response that it's only the vaccinated who are spreading pertussis - I suppose any unvaccinated person who contracts pertussis cannot possibly transmit it? Admittedly, the pertussis vaccination is not perfect and some may contract the disease but not very many.
Also the idea that the vaccinated well person can transmit the disease is ludicrous! The vaccine contains an attenuated virus that has an essentially 0% chance of causing the active disease. In addition, the principal mode of transmission of pertussis is droplet spray while coughing which is a predominant symptom of an active pertussis infection. Anyone who does not have an active coughing case of pertussis is not a problem.
Don't mess with me when it comes to epidemiology. Just imagine how many cases of pertussis and deaths there would be WITHOUT a significant number of the population vaccinated - Welcome back to the dark ages!