Pertussis outbreak?!

There is an outbreak of pertussis (almost 30 cases) about an hour from where we live with our 9 month old. He has not had his DTaP vaccinations (he had a reaction to one of his first vaccines and we are waiting until 12 months to try again). His pediatrician is located in the county with the pertussis outbreak and he has an appointment scheduled for day after tomorrow (his 9 month checkup) and it's an important one because he has fallen significantly off his growth curve, however, I feel like taking him to a pediatrician in a county in which I KNOW there is a whooping cough outbreak is just plain irresponsible... what should I do? Also, is it an overreaction to not take him out to the store, etc. for the next few weeks?

I'm just feeling a lot of mama anxiety and I'm unsure if it's rational or not. Help me out here ladies. 💕