Table 1. Descriptive statistics and results of analyses for the total population and the elderly population.
| Country | Seasons included in analyses | Number of seasons | Median vaccination coverage (%) (min-max) | Change in vaccination coverage (%) a | Median ILI incidence b (min-max) | Spearman rank correlation | Negative binomial regression model | |||
|---|---|---|---|---|---|---|---|---|---|---|
| ρ | P-value | IRR c | 95% CI | |||||||
| Lower | Upper | |||||||||
| The total population | ||||||||||
| France d | 2001/2002–2011/2012 | 11 | 21 (18–24) | +3% | 5267 (4900–5931) | 0.49 | 0.13 | 1.00 | 0.70 | 1.43 |
| Germany d | 2001/2002–2012/2013 | 12 | 27 (17–33) | -10% | 3579 (3092–4358) | -0.26 | 0.41 | 0.99 | 0.87 | 1.12 |
| Hungary | 2006/2007–2013/2014 | 8 | 10 (9–12) | -1% | 363 (289–515) | 0.87 | 0.005 | 1.17 | 0.58 | 2.34 |
| Italy | 1999/2000–2013/2014 | 15 | 18 (11–20) | +5% | 884 (413–2164) | 0.07 | 0.81 | 1.03 | 0.85 | 1.27 |
| Latvia d | 2003/2004–2013/2014 | 11 | 1 (0–14) | -2.2% | 3287 (2731–3810) | -0.25 | 0.47 | 1.00 | 0.85 | 1.17 |
| Lithuania | 2005/2006–2012/2013 | 8 | 6 (2–8) | +3% | 134 (15–162) | -0.04 | 0.93 | 1.00 | 0.68 | 1.48 |
| The Netherlands | 1991/1992–2013/2014 | 23 | 18 (7–22) | +12% | 172 (79–289) | -0.60 | 0.003 | 0.95 | 0.86 | 1.04 |
| Portugal | 2001/2002–2013/2014 | 13 | 17 (14–20) | 0% | 94 (21–129) | 0.10 | 0.74 | 1.02 | 0.73 | 1.43 |
| Romania | 2004/2005–2012/2013 | 9 | 8 (3–17) | -4% | 9 (5–60) | -0.43 | 0.24 | 0.92 | 0.79 | 1.07 |
| Slovakia | 2006/2007–2013/2014 | 8 | 10 (5–13) | +6% | 758 (459–1239) | 0.75 | 0.03 | 1.06 | 0.85 | 1.33 |
| Spain | 2002/2003–2012/2013 | 11 | 23 (14–24) | -5% | 208 (146–321) | -0.12 | 0.72 | 1.01 | 0.83 | 1.22 |
| The elderly (age ≥65 or ≥60, depending on country) population | ||||||||||
| Denmark | 2002/2003–2013/2014 | 12 | 49 (30–55) | +17% | 167 (57–310) | -0.11 | 0.74 | 0.98 | 0.90 | 1.06 |
| England | 1996/1997–2012/2013 | 17 | 72 (49–75) | +19% | 38 (17–143) | -0.81 | < 0.001 | 0.93 | 0.88 | 0.99 |
| France d | 2001/2002–2013/2014 | 13 | 64 (52–67) | -13% | 2781 (1896–3443) | 0.58 | 0.04 | 1.00 | 0.90 | 1.12 |
| Germany d | 2000/2001–2012/2013 | 13 | 49 (31–59) e | +6% | 1467 (1128–2105) | -0.57 | 0.04 | 0.99 | 0.92 | 1.06 |
| Ireland | 2003/2004–2013/2014 | 11 | 61 (54–70) | -3% | 34 (20–54) | 0.01 | 0.99 | 1.00 | 0.87 | 1.15 |
| Italy | 1999/2000–2013/2014 | 15 | 63 (41–68) | +14% | 298 (55–786) | -0.32 | 0.24 | 0.98 | 0.92 | 1.05 |
| Latvia d | 2006/2007–2013/2014 | 8 | 2 (2–3) | +0.5% | 633 (425–1440) | -0.02 | 0.95 | 1.21 | 0.19 | 7.77 |
| The Netherlands | 1991/1992–2013/2014 | 23 | 81 (28–84) | +44% | 158 (56–231) | -0.40 | 0.06 | 0.99 | 0.97 | 1.02 |
| Portugal | 1998/1999–2013/2014 | 16 | 45 (31–55) | +19% | 46 (8–166) | 0.09 | 0.74 | 0.98 | 0.91 | 1.06 |
| Romania | 2004/2005–2012/2013 | 9 | 19 (15–53) | -2% | 3 (2–23) | -0.03 | 0.93 | 0.97 | 0.92 | 1.02 |
| Slovakia | 2006/2007–2013/2014 | 8 | 25 (15–36) e | -10% | 223 (134–469) | 0.57 | 0.14 | 1.02 | 0.93 | 1.13 |
| Spain | 1997/1998–2013/2014 | 17 | 64 (56–70) | -11% | 61 (32–261) | -0.06 | 0.82 | 1.02 | 0.91 | 1.15 |
a Overall change in vaccination coverage trend was calculated taking the difference between the first and last season included in analysis.
b Incidence of influenza-like illness (ILI) or acute respiratory infection (ARI) was calculated by (sum of ILI or ARI cases / denominator (source population))*10,000 persons
c IRR: incidence rate ratio per percentage point change in influenza vaccination coverage
d Country reported acute respiratory infection (ARI), instead of influenza-like illness (ILI)
e Vaccination coverage of the elderly population measured for age ≥60 years instead of ≥65 years