title: Clinical and epidemiological picture of B pertussis and B parapertussis infections after introduction of acellular pertussis vaccines.
abstract: OBJECTIVE
  To investigate the clinical picture and frequency of Bordetella pertussis and B parapertussis infections after introduction of acellular pertussis (acP) vaccines in Germany.
  
  
  METHODS
  Prospective surveillance for B pertussis and B parapertussis in 14 144 toddlers. Pertussis vaccination coverage was 86%, either with acP (75%) or whole cell pertussis (wcP) vaccine (11%). All children presenting with cough for more than seven days were examined for B pertussis and B parapertussis by culture, PCR, and serology (for cough duration > or =21 days).
  
  
  RESULTS
  There were 180 Bordetella infections; 116 (64%) were caused by B pertussis and 64 (36%) by B parapertussis. Incidence rates were 4.8 and 2.8 per 1000 person-years, respectively. Paroxysmal cough, post-tussive whooping, and vomiting > or = 21 days was found in 53%, 22%, and 8% of all B pertussis cases and in 22%, 5%, and 0% of all B parapertussis cases, respectively. A total of 81/116 (70%) B pertussis cases and 56/64 (87.5%) B parapertussis cases had received at least one dose of pertussis vaccine. Typical pertussis with paroxysmal cough > or = 21 days was present in 29/35 (83%) unvaccinated B pertussis cases, in contrast to 33/81 (41%) vaccinated B pertussis cases.
  
  
  CONCLUSIONS
  Following the increase of pertussis vaccination coverage, we observed a relative increase of B parapertussis cases in comparison to B pertussis cases. In vaccinated children B pertussis disease frequently presented as a mild disease, clinically difficult to distinguish from diseases associated with coughing caused by B parapertussis and other viral or bacterial infections.
authors.affiliation: University Childrens Hospital Munich, Ludwig-Maximilians-Universität, Lindwurmstr. 4, 80337 Munich, Germany. Johannes.Liese@kk-i.med.uni-muenchen.de
authors.forename: J G
authors.initials: JG
authors.lastname: Liese
authors.forename: C
authors.initials: C
authors.lastname: Renner
authors.forename: S
authors.initials: S
authors.lastname: Stojanov
authors.forename: B H
authors.initials: BH
authors.lastname: Belohradsky
mesh_terms: D001885:Bordetella Infections / Q000150:complications / Q000453:epidemiology* / Q000517:prevention & control*; D002648:Child; D002675:Child, Preschool; D003371:Cough / Q000382:microbiology; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D010567:Pertussis Vaccine; D011159:Population Surveillance; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000209:etiology; D014839:Vomiting / Q000382:microbiology; D014917:Whooping Cough / Q000150:complications / Q000453:epidemiology / Q000517:prevention & control
chemical_list: D010567:Pertussis Vaccine