455. Serotype-specific trends in population based surveillance for invasive and respiratory pneumococcal disease in adults, Toronto, 2000-2012
Session: Poster Abstract Session: Pneumococcal Vaccine in Children and Adults
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C

Background: Invasive disease (IPD) and non-bacteremic pneumonia (NBPP) contribute to pneumococcal disease burden in adults. The effects of PCV programs on adult disease is unknown.

Methods: In Ontario, PCV7 was authorized in ‘01, and publicly funded infant programs introduced for PCV7 in 1/05, PCV10 in 10/09 and PCV13 in 11/10. As of ‘13, PCV13 is recommended for immunosuppressed adults. TIBDN has performed population-based surveillance for IPD since 1995 and respiratory pneumococcal disease (RPD) since 2002.

 

RPD are classified as ‘confirmed NBPP', ‘probable NBPP', ‘possible NBPP' and not associated with acute respiratory disease (‘ND'). Serotyping and susceptibility testing are done as per CLSI standards. Clinical data are obtained from patient/physician interview and chart review.  

Results: From 2002-12, 3412 adult (≥15y) RPD cases and 2798 cases of IPD were identified. RPD classifications were 603 confirmed NBPP, 647 probable NBPP, 399 possible NBPP, 1130 ND, and 633 not classifiable.

The IPD rate decreased 10 to 7.5/100000/y (2002 – 05), then to 4.7/100000/y in 2012; among adults ≥65 y old, IPD decreased 34 to 18.7/100000/y. From 2002-12, the RPD rate decreased 9.5 to 5.4/100000/y. Confirmed NBPP decreased 1.6 to 0.9/100000/y (all adults), and from 7.7 to 2.7/100000/y among adults ≥65 y old. 

From 2002-12, the percent of PCV13/not PCV7 ST isolates increased from 16 to 42% in IPD, 22 to 30% in NBPP.  The percent of non-vaccine STs increased in all groups, with higher percent (>50%) among RPD vs IPD.

The STs differed between IPD and RPD.  4, 14, 19A, 7F and 6C are more common from IPD; 3, 6A,19F, 11A, 35B are more common from confirmed/probable NBPP. 

Conclusion: Since introduction of pediatric PCV7/13, incidence of adult IPD/RPD due to PCV7 STs has decreased; since the introduction of PCV13, rates of PCV13 disease have stabilized.  The distribution of STs among IPD and RPD differs.

Altynay Shigayeva, PhD1, Allison Mcgeer, MD, MSc, FRCPC1,2, Karen Green, MSc1,2, Wallis Rudnick, MSc1,2, Sylvia Pong-Porter, MLT1, Agron Plevneshi1,2 and Toronto Invasive Bacterial Diseases Network, (1)Mount Sinai Hospital, Toronto, ON, Canada, (2)Toronto Invasive Bacterial Diseases Network, Mount Sinai Hospital, Toronto, ON, Canada

Disclosures:

A. Shigayeva, None

A. Mcgeer, None

K. Green, None

W. Rudnick, None

S. Pong-Porter, None

A. Plevneshi, None

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