[exDemMom]

+From the article, 2 of the 895 weren't up to date on their shots. There was another article on FR last month reporting about the same. That's a whole lot less than 90% effective.

The article said that of the new cases, all but 2 were up to date on their shots. There were 9 new cases, so 7 were fully vaccinated. This does not change the estimation of 90% effective, because we don't know how many vaccinated people were exposed and did not come down with whooping cough.

[Bogey78O]

Also, considering that an adult who had a shot is considered up to date because the TDAP is a recommended vaccine and not a required one. Even though they may not have had the shot in 30 years.