Development of improved vaccines against whooping cough Current status

Prior to the introduction of killed whole cell pertussis vaccine (wP) in the 1940s, whooping cough was a major cause of infant death worldwide. Widespread vaccination of children with this vaccine caused a significant reduction in mortality. However, in the 1990s and now more recently, there has been a resurgence of pertussis in several countries even in populations previously vaccinated with an acellular pertussis vaccine (aP). In this review we describe the epidemiology of whooping cough, the vast array of virulence factors produced by this pathogen potentially contributing to the resurgence of pertussis even in previously vaccinated populations of infants and children, history of whooping cough prophylaxis, possible mechanisms of immunity, lack of availability of a suitable non-toxic adjuvant capable of inducing both arms of the immune response, and the current status of development of improved vaccines with potential to induce longer-lasting protection, than is currently possible with the wP or aP vaccines, against whooping cough.