1. Regional analysis: patterns of influenza B circulation in the Americas
Rakhee Palekar, MD, MPH
PAHO/WHO

2. Background Influenza A subtype H1, H3, etc
Influenza B distinct lineages emerged in 1970’s B-Yamagata & B-Victoria co-circulated since 2001

3. Influenza in Americas, 2010−2015
North America
Central America, Caribe, South America

4. Relative Proportion of Influenza B
THINK ABOUT HOW ELSE TO PRESENT THESE DATA

5. Influenza B in United States, 2001−2015
Percent
Influenza Season

6. Influenza B Regional Analysis
Questions to answer:
What is the burden of influenza B relative to influenza A
What is the burden of B/Yam relative to B/Vic
3. How does the epidemiology of influenza A differ from influenza B
4. How does the epidemiology of B/Yam differ from B/Vic
Compile epidemiologic data from influenza B cases
Compare to influenza A
Compare B/Yam to B/Vic

7. Influenza B Regional Analysis
Period of analysis:
All countries in Americas eligible to participate
Data needed to answer analysis questions:
Counts of influenza A and B cases (including B lineage)
Epidemiologic characteristics of influenza A and B cases (date of illness onset, hospitalization, treatment, risk factors, vaccination, death)
Compile epidemiologic data from influenza B cases
Compare to influenza A
Compare B/Yam to B/Vic

8. Influenza B in LAC*, 2010−2015
ADD LINES to separate the seasons
ADD N for YAM and VIC
*Argentina, Bolivia, Brazil, Colombia, Costa Rica, Chile, CARPHA, El Salvador, Ecuador, Guatemala, Jamaica, Mexico, Panama, Paraguay, Peru , Uruguay

9. Predominant Influenza B Lineage,2012
Country with vaccine mismatch
ADD MISMATCH

10. Predominant Influenza B Lineage,2013
Country with vaccine mismatch

11. Predominant Influenza B Lineage,2014
Country with vaccine mismatch
Mexico

12. Hospitalized Influenza B-Yam & B-Vic Cases*, 2012−2015
B/VICTORIA n=409
% (n)
B/YAMAGATA
n=686
P VALUE
Co-morbid conditions
24.4 (100)
29.3 (201)
0.08
Vaccinated
9.8 (40)
14.0 (96)
0.04
Deceased
4.6 (19)
3.8 (26)
0.49
Argentina,Chile,Colombia,Costa Rica,Cuba,Ecuador,El Salvador,Guatemala,Jamaica,Mexico,Panama,Paraguay,Peru,Uruguay
*Argentina,Chile,Colombia,Costa Rica,Cuba,Ecuador,El Salvador,Guatemala,Jamaica,Mexico,Panama,Paraguay,Peru,Uruguay

13. Conclusions
Influenza B important each season in all subregions of the Americas
Both B lineages circulate in the Americas with variable predominance
Vaccine mismatch from year to yearimportant to answer questions about vaccine impact to determine benefit of quadrivalent vaccine
More data needed from countries to better delineate epidemiology of B lineages and compare A and B cases

14. Next Steps Receive data from additional countries (May-June 2016)
Complete analysis (June 2016)
Share results with participating countries to receive feedback (July 2016)

15. Gracias!
Contact flu team at and to participate in the analysis