Re: Tdap vaccine - how often?
The information that I have seen is that a pertussis booster for adults is one time. I.e. when getting Td (tetanus + diptheria) vaccine every 10 years, substitute one such Td vaccine with Tdap (tetanus + diptheria + pertussis) vaccine, then continue with Td vaccine every 10 years.
It is influenza vaccines that are commonly given every year, because influenza mutates frequently.