[Impact of 7-valent pneumococcal conjugate vaccination in a population with low to intermediate vaccination levels].
OBJECTIVE
To analyze the changes occurring in declared cases (microbiological report) of invasive pneumococcal disease (IPD) in children <2 years old in Catalonia (Spain) after the 7-valent pneumococcal conjugate vaccine (PCV7) was licensed for use.


METHODS
Cases of IPD in children <2 years old were obtained from notifications to the Microbiological Reporting System of Catalonia (MRSC) in 1997-1999 and 2002-2004 by the hospitals (n=23) that have participated in the MRSC continuously and uninterruptedly since its inception in 1995.


RESULTS
Overall reported rates were 49.2 cases per 100,000 persons-year in 1997-1999 and 40.4 per 100,000 persons-year in 2002-2004; the difference was not statistically significant. The rate of bacteremic pneumonia fell from 25.2 per 100,000 persons-year in 1997-1999 to 21.6 per 100,000 persons-year in 2002-2004, and meningitis from 6.0 to 4.3 per 100,000 persons-year; again, differences were not statistically significant (P>0.05).


CONCLUSIONS
After PCV7 was licensed for use, a noticeable, but non-significant, reduction in reported IPD rates in children <2 years old occurred in Catalonia. If the results had been statistically significant, the overall reduction would have been 17.90%, not far below the theoretically expected reduction (22%), based on the protective efficacy of PCV7 (89%), the percentage of invasive disease-causing serotypes included in the vaccine (70%), and the vaccination coverage achieved during the study period (35%).
Salleras
Lluís
L
Departamento de Salud Pública, Universidad de Barcelona, Barcelona, Spain. salleras@ub.edu
Domínguez
Angela
A
Ciruela
Pilar
P
Izquierdo
Conchita
C
Borràs
Eva
E
D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D011008:Pneumococcal Infections / Q000517:prevention & control*; D022242:Pneumococcal Vaccines; D014611:Vaccination / Q000706:statistics & numerical data*; D018074:Vaccines, Conjugate
D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate