Download Influenza Epidemiology

Influenza Epidemiology
Global Hospitalizations and Potential
Vaccination Strategies
Katie Lafond, MPH
PhD Candidate, University of Tampere
Fulbright Seminar, March 18, 2016
➔ Introduction to influenza
➔ Summary of research
Influenza: Background
Virus Basics:
● Many types and subtypes
● Wide range of animal hosts
● Rapid mutation rate
○
Genetic drift (annual vaccine)
○
Genetic shift (pandemic strains)
Recorded human pandemic influenzas since 1885
(early subtypes inferred)
From: Nicholl, A. Eurosurveillance, Vol 15 (1): January 2010
Influenza Epidemiology
1.
Seasonal transmission patterns
2.
Severe disease most common in:
a. Pregnant women
b. Infants
c. Older adults
d. Those with underlying conditions
3.
Vaccines vary in effectiveness:
a. By year
b. By vaccine type
c. By target population
Images: Chinadaily.com.cn (top left), CDC Public Health Image Library
Dissertation Projects
1. To better understand the role of influenza in
respiratory hospitalizations worldwide
2. To explore strategies for vaccination in
lower-income settings
To better understand the role of influenza in respiratory
hospitalizations worldwide:
1. Estimate the contribution of influenza
viruses among respiratory hospitalizations
in published literature and among a global
working group of influenza researchers
To explore strategies for vaccination in lower-income
settings:
2. Use simulation models to compare the
cost-effectiveness and epidemiological
impacts of different vaccination strategies in
a community of northern India
Project 1: Influenza hospitalizations
Methods
Conduct systematic literature review in
conjunction with data from global working
group of influenza researchers
Analyze inpatient data on number of
individuals tested and positive for
influenza viruses
Compare these findings by age group,
geographic region and country income
status
Key Findings
●
Influenza associated with:
○ 6% of acute respiratory
hospitalizations in children <2 years
○ 16% of these hospitalizations in older
(school-aged) children
●
Preliminary adult data:
○ 10-11% of acute respiratory
hospitalizations
○ No clear age-based trend
Project 2: Vaccine impact in India
Specific Aims
●
●
Develop a model to estimate the
epidemiologic and economic impacts
of vaccinating different WHO target
groups in a community near Delhi,
India
Compare model results for:
○ Single dose of locally-produced
live vaccine
○ Two doses of imported
inactivated vaccine
Methods
●
●
●
Study population: Ballabgarh, India
Static model using local data on:
○ Vaccine effectiveness
○ Disease burden
○ Vaccination costs
Several options for expansion:
○ Indirect vaccine effects
○ Transmission dynamics
Why Finland
● International Doctoral Programme in Epidemiology @ University of Tampere
○ Applied public health and epidemiology doctoral program
○ Global scope, access to world-class researchers
■ Infectious disease epidemiology
■ Vaccine-preventable diseases
■ Cancer epidemiology and chronic disease
● Finland’s centralized/registry-based public health system
○ Ideal setting for epidemiological best practices
● Support from the Fulbright Center of Finland specifically for degree-seeking
PhD candidates
Thank you -- Kiitos
★
University of Jyväskylä
★
Fulbright Center of Finland
★
Center for International Mobility (CIMO)
★
University of Tampere
★
○
IPPE
○
School of Health Sciences
US Centers for Disease Control and Prevention (CDC)
○
★
Influenza Division
“Global Respiratory Hospitalizations - Influenza
Proportion Positive” (GRIPP) working group