"I-MOVE" towards monitoring seasonal and pandemic influenza vaccine effectiveness: lessons learnt from a pilot multi-centric case-control study in Europe, 2008-9.
Within I-MOVE (European programme to monitor seasonal and pandemic influenza vaccine effectiveness (IVE)) five countries conducted IVE pilot case-control studies in 2008-9. One hundred and sixty sentinel general practitioners (GP) swabbed all elderly consulting for influenza-like illness (ILI). Influenza confirmed cases were compared to influenza negative controls. We conducted a pooled analysis to obtain a summary IVE in the age group of >or=65 years. We measured IVE in each study and assessed heterogeneity between studies qualitatively and using the I2 index. We used a one-stage pooled model with study as a fixed effect. We adjusted estimates for age-group, sex, chronic diseases, smoking, functional status, previous influenza vaccinations and previous hospitalisations. The pooled analysis included 138 cases and 189 test-negative controls. There was no statistical heterogeneity (I2=0) between studies but ILI case definition, previous hospitalisations and functional status were slightly different. The adjusted IVE was 59.1% (95% CI: 15.3-80.3%). IVE was 65.4% (95% CI: 15.6-85.8%) in the 65-74, 59.6% (95% CI: -72.6 -90.6%) in the age group of >or=75 and 56.4% (95% CI: -0.2-81.3%) for A(H3). Pooled analysis is feasible among European studies. The variables definitions need further standardisation. Larger sample sizes are needed to achieve greater precision for subgroup analysis. For 2009-10, I-MOVE will extend the study to obtain early IVE estimates in groups targeted for pandemic H1N1 influenza vaccination.
Kissling
E
E
EpiConcept, Paris, France. e.kissling@epiconcept.fr
Valenciano
M
M
Falcao
Jm
J
Larrauri
A
A
Widgren
K
K
Pitigoi
D
D
Oroszi
B
B
Nunes
B
B
Savulescu
C
C
Mazick
A
A
Lupulescu
E
E
Ciancio
B
B
Moren
A
A
D000368:Aged; D016022:Case-Control Studies; D004196:Disease Outbreaks / Q000706:statistics & numerical data; D005060:Europe / Q000453:epidemiology; D005194:Family Practice; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology* / Q000302:isolation & purification; D007252:Influenza Vaccines / Q000592:standards*; D007251:Influenza, Human / Q000453:epidemiology* / Q000517:prevention & control; D007407:Interviews as Topic; D008297:Male; D010865:Pilot Projects; D011159:Population Surveillance / Q000379:methods*; D015397:Program Evaluation
D007252:Influenza Vaccines