Background: In 2001, the 1st pneumococcal conjugate vaccine (PCV) was authorized in Ontario, Canada. Publicly funded PCV7 was introduced in 1/2005 (3+1 schedule), PCV10 in 10/2009 and PCV13 in 11/2010 (2+1 schedule with catchup to 35m). TIBDN performs population-based surveillance for invasive pneumococcal disease (IPD) in Toronto/Peel to evaluate program impact.
Methods: IPD cases are reported to a central office and one isolate/case is serotyped. Demographic/ clinical data are collected by chart review and patient/physician interview.
Results: From 1/2001–4/2015, 6076 IPD cases were identified. 17% of cases were aged <15y, 44% were aged 15–64y and 40% were aged ≥65y.
The IPD rate in adults decreased from 8/100000/y in 2005–2010 to 6/100000/y in 2013/14. In children, the IPD rate decreased from local peak of 11/100000/y in 2009 to 5/100000/y in 2013/14. Since 2009, IPD due to PCV13 STs has decreased in both children and adults (Figure 1).
Since the introduction of PCVs, nonPCV ST IPD increased from 2.6 to 3.8/100000/y among adults and from 1.4 to 2.8/100000/y among children (2001–2004 vs 2010–2014).
From 1/2014–4/2015, ST was available for 472 (87%) IPD cases. NonPCV STs represented 64% of adult and 60% of pediatric cases. PCV13 STs 19A and 3 remained the most common ST among adults (11% and 10%) and children (30% and 10%). Most common nonPCV STs were 22F (10%), 23A (7%) and 9N (5%) among adults and 15C (10%), 22F (8%) and 23B (6%) among children.
From 1/2013–4/2015, 37 pediatric cases were due to PCV13/non7 STs. Of these, 3 were PCV13 ineligible (aged >35 mos when catchup program implemented). Of the 34 vaccine-eligible children (10 in 2013, 18 in 2014, and 6 Jan-Apr 2015), vaccine history is available for 30. One case immigrated to Ontario at age 4 (history of PCV7); 14 cases occurred in children who missed ≥1 scheduled doses (12 ST19A, 2 ST3); 6 cases occurred in children eligible for a single dose of PCV13 only (4 ST3, 2 ST19A); 1 case (ST3) occurred in an 11 month old child who had received doses at 2 and 4 mos; and 8 vaccine failures were identified (5 ST19A, 2 ST3, 1 ST5).
Conclusion: Since PCV13-program implementation, the IPD rate due to PCV13/not7 STs has decreased in children and adults. NonPCV ST IPD has increased somewhat and now represents 60% of pediatric and 64% of adult cases.
GSK: Investigator , Research support
K. Green, None
A. Plevneshi, None
S. Pong-Porter, None