Eradication of invasive pneumococcal disease due to the seven-valent pneumococcal conjugate vaccine serotypes in Calgary, Alberta.
BACKGROUND
The seven-valent pneumococcal conjugate vaccine (PCV7) was licensed in Canada in 2001. Routine infant vaccination programs in Alberta began in 2002. Several years after PCV7 introduction, the routine use of PCV7 in infants and high-risk children has led to near elimination of invasive pneumococcal disease (IPD) caused by vaccine serotypes.


METHODS
Prospective, population-based surveillance of all IPD cases was conducted from January 1998 to December 2010. Demographic, clinical and microbiologic data were collected.


RESULTS
There were 1462 IPD cases over 13 years. Comparing PCV7 serotype IPD incidence in the prevaccine period (1998-2001) to the late postvaccine period (2007-2010), there were declines in children 0-5 months (100%), 6-23 months (98%), 2-4 years (97%), 5-15 years (100%) as well as in adults 16-64 years (73%), 65-84 years (90%) and ≥85 years of age (100%). From 2008 to 2010, there were no cases of PCV7 serotype IPD in children under 2 years of age. There have been increases in non-PCV7 serotype IPD; notably, serotypes 5 and 19A have increased significantly in adults and 19A in children.


CONCLUSIONS
PCV7 serotype IPD has been eliminated in vaccine-eligible young children and nearly eliminated in all other age groups. Serotype 19A increased significantly at all ages before the introduction of an expanded valency pneumococcal conjugate vaccine.
Departments of Pediatrics, University of Calgary; §Department of Medicine, University of Calgary, Calgary, Canada.
Jenine
J
Leal
Otto G
OG
Vanderkooi
Deirdre L
DL
Church
Judy
J
Macdonald
Gregory J
GJ
Tyrrell
James D
JD
Kellner
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000416:Alberta / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D060740:Disease Eradication; D005260:Female; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D011446:Prospective Studies; D013296:Streptococcus pneumoniae / Q000145:classification / Q000302:isolation & purification
D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022242:Pneumococcal Vaccines