Four and One-Half-Year Follow-up of the Effectiveness of Diphtheria-Tetanus Toxoids-Acellular Pertussis/Haemophilus influenzae Type b and Diphtheria-Tetanus Toxoids-Acellular Pertussis-Inactivated Poliovirus/H. influenzae Type b Combination Vaccines in Germany

Background: Recently an increase in the number of invasive Haemophilus influenzae type b (Hib) cases was observed in the United Kingdom, which coincided with a temporary change from diphtheria-tetanus toxoids-wild-type pertussis to diphtheria-tetanus toxoids-acellular pertussis (DTaP) Hib vaccines. A study in Germany based on approximately 2 years of follow-up, estimated vaccine effectiveness (VE) of DTaP/Hib and DTaP-inactivated poliovirus/Hib combination vaccines against invasive Hib disease to be high. Objectives: To assess VE of DTaP-containing Hib vaccines against Hib in Germany with the use of extended follow-up of case surveillance and vaccine uptake. Subjects and Methods: Cases with…