Both disease-acquired and vaccine-acquired immunity to pertussis (whooping cough) wane with time, so that several infections can occur in an individual's lifetime. The severity of a pertussis infection depends on how low the immunity has declined since the previous vaccination, infection, or exposure. In the United States five DTP or DTaP (diphtheria-tetanus-pertussis) vaccinations are recommended at ages 2, 4, 6, 15-18 months, and 4-6 years. The new acellular pertussis vaccine (aP) has fewer side effects, so that it is safe for adults. New strategies for reducing pertussis incidence include: 1) combining the aP vaccine with the current Td (tetanus-diphtheria) booster that is now recommended every ten years, 2) giving the aP vaccine to adults at age 50 years, and 3) giving the aP vaccine to adolescents. The effects of these vaccination strategies are analysed using an age-structured model.

Back to Workshop Schedule

1998-1999 Mathematics in Biology