AMMI Canada /CPHA Co-developed Accredited Learning Activity
December 3, 2014 Dat Tran, MD, MSc Staff Physician, Division of
Infectious Diseases The Hospital for Sick Children
[email protected] Two Bs? Or not Two Bs?Examining Quadrivalent
Influenza Vaccines Epidemiology of influenza and burden of
influenza B Slide 2 Faculty/Presenter Disclosure Faculty: Dr. Dat
Tran Relationships with commercial interests: Grants/Research
Support: -Novartis Vaccines via CPS -GSK via CPS -Hoffman La Roche
-Sanofi Pasteur via Clinical Trials Research Center/Canadian Center
for Vaccinology Other: Employee of The Hospital for Sick Children
Slide 3 Mitigating Potential Bias The planning committee has deemed
there to be no potential for bias or conflict of interest in
relation to the speaker(s) declaration(s) and the workshop content.
All speakers were independently selected by the Education Planning
committee. No speakers have received an honorarium for this
session. Slide 4 Outline Background Epidemiology of influenza
Burden of influenza B Conclusions Outline Background Epidemiology
of influenza Burden of influenza B Conclusions Slide 5 An influenza
virus Outline Background Epidemiology of influenza Burden of
influenza B Conclusions
http://www.cdc.gov/flu/images/virus/fluvirus-antigentic-characterization-large.jpg
Slide 6 Influenza infection Outline Background Epidemiology of
influenza Burden of influenza B Conclusions
http://www.cdc.gov/flu/images/influenza-virus-labels.jpg Slide 7 3
types of influenza viruses Influenza A Found in many animals
(ducks, chickens, pigs, whales, horses, seals) Wild birds = natural
hosts Responsible for all pandemics Influenza B Circulates widely
only in humans Influenza C Causes mild infection in humans Does not
cause epidemics Outline Background Epidemiology of influenza Burden
of influenza B Conclusions Slide 8 Antigenic drift and shift Drift
Gradual change due to point mutations in H & N Occurs in both A
and B viruses Localized or worldwide spread Shift Occurs through
reassortment of genes Sudden change Occurs only in influenza A
viruses Worldwide spread (pandemic) Outline Background Epidemiology
of influenza Burden of influenza B Conclusions
http://www.medscape.org/viewarticle/433151_1 Slide 9 Influenza
affects millions of people each year in Canada Outline Background
Epidemiology of influenza Burden of influenza B Conclusions Deaths
(~4000) Hospitalizations (up to 20,000) Physician visits (I&P
excess rates of 2000- 5000/100K) Work-days lost (1.5 million;
10-12% of all absence from work) Infections (10-20% of population
or 3.5-7 million) ACS NACI Statement on Seasonal Influenza Vaccine
for 2014-2015; Menec et al, CJPH 2003 Slide 10 Laboratory-confirmed
influenza cases in Canada by type and season Outline Background
Epidemiology of influenza Burden of influenza B Conclusions ACS
NACI Statement on Seasonal Influenza Vaccine for 2014-2015 Slide 11
Laboratory-confirmed influenza B cases by age group & season
Outline Background Epidemiology of influenza Burden of influenza B
Conclusions ACS NACI Statement on Seasonal Influenza Vaccine for
2014-2015 12.9% 40.2% 1.4% 16.6% 39.4% 12.8% 42.5% 39.7% 0.1% 14.6%
53.1% 16.1% Slide 12 Incidence of influenza B in Ontario by age
group and season Outline Background Epidemiology of influenza
Burden of influenza B Conclusions *2013-2014 season only includes
cases reported up to the end of Week 28 (July 12, 2014). Note:
Counts from 2009-2010 are underreported and should be interpreted
with caution due to modified reporting during the pandemic. Source:
(Case data) Ontario Ministry of Health and Long-Term Care,
integrated Public Health Information System (iPHIS) database,
extracted by Public Health Ontario [2014/07/15]; (Population data)
Population Estimates 1986-2013, Ontario Ministry of Health and
Long-Term Care, IntelliHEALTH ONTARIO, date extracted [2014/07/02].
Slide courtesy of Public Health Ontario Slide 13 Institutional
outbreaks of influenza in Ontario by type and season Outline
Background Epidemiology of influenza Burden of influenza B
Conclusions Slide courtesy of Public Health Ontario *Note:
2013-2014 season only includes outbreaks reported up to the end of
Week 28 (July 12, 2014). Outbreaks with a missing date of onset
were excluded. Source: Ontario Ministry of Health and Long-Term
Care, integrated Public Health Information System (iPHIS) database,
2006-2007 data extracted [2007/11/16]; 2007-2008 data extracted
[2008/09/25]; 2008-2009 data extracted [2009/09/08]; 2009-2010 data
extracted [2010/09/09]; 2010-2011 data extracted by Public Health
Ontario [2011/09/07]; 2011-2012 data extracted by Public Health
Ontario [2012/11/06]. 2012-2013 data extracted by Public Health
Ontario [2014/05/06]. 2013-2014 data extracted by Public Health
Ontario [2014/07/17]. Slide 14 Circulating B lineage vs WHO
recommended B lineage Outline Background Epidemiology of influenza
Burden of influenza B Conclusions ACS NACI Statement on Seasonal
Influenza Vaccine for 2014-2015
12.9%40.2%1.4%16.6%39.4%12.8%42.5%39.7%0.1%14.6%53.1%16.1% RVDSS:
Slide 15 Circulating B lineage vs WHO recommended B lineage Outline
Background Epidemiology of influenza Burden of influenza B
Conclusions ACS NACI Statement on Seasonal Influenza Vaccine for
2014-2015
12.9%40.2%1.4%16.6%39.4%12.8%42.5%39.7%0.1%14.6%53.1%16.1% RVDSS:
IMPACT: 30.7% 38.1% 15.3% 36.9% 46.9% 0% 32.8% 58.3% 29.6% Slide 16
Circulating B lineage vs WHO recommended B lineage Outline
Background Epidemiology of influenza Burden of influenza B
Conclusions ACS NACI Statement on Seasonal Influenza Vaccine for
2014-2015
12.9%40.2%1.4%16.6%39.4%12.8%42.5%39.7%0.1%14.6%53.1%16.1% RVDSS:
IMPACT: 30.7% 38.1% 15.3% 36.9% 46.9% 0% 32.8% 58.3% 29.6%
CNISP/SOS: 9.3% 54.1% 7.7% Slide 17 Characteristics of influenza B
versus A in hospitalized individuals Outline Background
Epidemiology of influenza Burden of influenza B Conclusions
Influenza BInfluenza A Hospitalization (IMPACT) Matched B seasons
Mismatched B seasons 36.3% (15.3 58.3) 28.5% (29.6 32.8) 40.6% (5.3
58.3) 63.7% (41.7 84.7) 71.5% (67.2 70.4) 59.4% (41.7 84.7)
Hospitalization (SOS) Matched B seasons Mismatched B seasons 7.7
54.1% 7.7 9.3% 54.1% 45.9 92.3% 90.7 92.3% 45.9% Age group (P/T) 0
4 5 14 15 19 20 44 45 64 65 8.6% 7.2% 0.6% 6.2% 18.3% 57.1% 16.9%
3.6% 1.1% 16.8% 30.6% 27.2% ICU admission (IMPACT)13.8%13.9%
Mortality (P/T)7.1%6.0% ACS NACI Statement on Seasonal Influenza
Vaccine for 2014-2015; FluWatch Slide 18 Characteristics of
influenza B versus A in hospitalized adults by type/subtype: SOS
(2011/12) Outline Background Epidemiology of influenza Burden of
influenza B Conclusions Slide courtesy of PCIRN SOS Network
VariableInfluenza A n = 161 Influenza B n = 299 A/H1N1 n=99 A/H3N2
n=61 B/Vic n=89 B/Yam n=204 Age mean (SD)55 (17.4)71.2 (20)61.5
(21)73.6 (17.1) 16-49y37 (37.4%)10 (16.4%)25 (28.1%)23 (11.3%)
50-64y27 (27.3%)5 (8.2%)18 (20.2%)36 (17.7%) 65-75y23 (23%)12
(19.7%)20 (22.5%)29 (14.2%) > 75y12 (12%)34 (55%)26 (29.2%)116
(56.9%) Male48 (48.5%)28 (45.9%)34 (38.2%)94 (46.1%) Admit from
LTCF010 (16.4%)10 (11.4)76 (37.3) Slide 19 Outcomes of influenza B
versus A in hospitalized adults by type/subtype: SOS (2011/12)
Outline Background Epidemiology of influenza Burden of influenza B
Conclusions Slide courtesy of PCIRN SOS Network VariableInfluenza A
n = 161 Influenza B n = 299 A/H1N1 n=99 A/H3N2 n=61 B/Vic n=89
B/Yam n=204 Mean LOS (SD)10.0 (10.4)10.4 (11.9) 9.3 (9.1)11.0
(12.4)11.3 (13.2)10.1 (11.4) Admit to ICU22 (13.7%)30 (10.0%) 15
(15.2%)7 (11.5%)12 (13.5%)18 (8.8%) 30d mortality10 (6.2%)23 (7.7%)
3 (3.0%)7 (11.5%)*3 (3.4%)20 (9.8%)* Slide 20 Conclusions Outline
Background Epidemiology of influenza Burden of influenza B
Conclusions Influenza is a major cause of morbidity and mortality,
and has an impact on social and economic well-being In 5 of last 12
non-pandemic influenza seasons, influenza B has accounted for 25%
of all cases Circulating and vaccine strains differed in 3 seasons
Co-circulation of both B lineages occurred in 4 th season Burden of
influenza B (relative to A) is, on average, greater when
circulating and vaccine strains do not match A heavy influenza B
season can occur even when circulating and vaccine strains match
Slide 21 Conclusions Outline Background Epidemiology of influenza
Burden of influenza B Conclusions Compared influenza A, a greater
proportion of hospitalized influenza B cases occurs in Children
aged 5 to 14 years Adults aged 65 years Among individuals
hospitalized with influenza, severity of influenza B is comparable
to that of influenza A Given the contribution of influenza B to the
incidence and serious outcomes related to influenza, use QIV may
offer benefits over TIV in supporting the goal of the Canadian
influenza immunization program
