Can we prevent the next epidemic? The elimination of childhood diseases by mass vaccination

Recently in New Zealand there have been outbreaks of measles and pertussis every six and ve years respectively. A model has been used to compare the dynamics of these diseases, and to determine the optimum ages at which children should be vaccinated against them. Whereas measles could be eliminated by giving the second vaccination at ve years instead of eleven, it is diÆcult to devise a practical scheme that would eliminate pertussis. It is then necessary to consider vaccination schemes in the light of the age-structure of future epidemics as well as their timing.