How are the sub-unit pertussis vaccines to be evaluated?

Although an effective whooping cough vaccine has been available in the UK since the 1950s, its current association with neurotoxicity has resulted in poor uptake: as a consequence major epidemics (with significant morbidity and mortality) are still being experienced. Component (sub-unit) vaccines, which incorporate those antigens thought to be concerned with generating a protective effect, have been developed and are now available for field testing. This paper addresses how such a vaccine might be evaluated, the organization of a trial and the difficulties to be expected.