Acellular pertussis vaccines pertinent issues.

Efficacy of whole cell pertussis vaccines (wP) in humans correlates with (and hence is measured by) the ‘mouse protection test’, wherein vaccinated mice are challenged with live B. pertussis. This test does not work similarly with acellular pertussis vaccines (aP); hence antibody levels to various antigens are measured as a surrogate marker of efficacy. This difference between the direct as compared to indirect demonstration of efficacy of wP and aP respectively should be recognized, especially as there is considerable debate on whether antibody levels closely correlate with protective efficacy against pertussis. JOSEPH L MATHEW ACELLULAR PERTUSSIS VACCINES