H1N1 Influenza Pandemic in Italy Revisited: Has the Willingness to Get Vaccinated Suffered in the Long Run?

Ludolph, Ramona; Nobile, Marta; Hartung, Uwe; Castaldi, Silvana; Schulz, Peter J.

When participants were asked how much effort they routinely put into their own health 11.4% reported to invest nothing at all or hardly anything. More than one third of respondents (36.4%) claimed to put not so much effort into their health and 45.7% estimated their effort as much. Only 6.4% of the sample considered themselves to invest very much in order to stay healthy. When it comes to the adoption of preventive behaviours, 40.0% of respondents report to be willing to seek vaccination during the next influenza pandemic (Table 2) . Thus, vaccination is the second most frequently chosen protective behaviour after avoiding larger gatherings of people, as Figure 1 shows. This contrasts rather impressively with 3.1% in our sample who affirmed to have received vaccination against H1N1 back in 2009/10. If those who could not remember whether they were vaccinated against H1N1 are added, the share of vaccinated persons is still not larger than 5.5%. This rather small percentage of people who received the H1N1 vaccine is in line with the share of vaccinated persons on a national level. In sum, there was a national coverage of 4.0% of first and second doses among the Italian target population consisting of healthcare workers, pregnant women, people at high risk under the age of 65, and institutionalised children and adolescents. 7 Considering the seasonal flu vaccinations, 10.1% say they normally receive them, and another 6.2% in some years. This reflects quite well the seasonal influenza vaccination rates on a national level: according to data of the Italian Health Ministry 14.9% of all Italians and 11.4% of residents in Lombardy, the region where Milan is located, received a vaccine against the seasonal influenza virus in 2012-2013. 38 The small number of people who received vaccination against the H1N1 virus in 2009/10 (N=4) created a minor difficulty in testing the relationship between past and future vaccination behaviour: as expected cell counts were very low, the calculation of a Chi-square test was not possible. Instead, Fisher's exact test was used and yielded an exact significance value of 0.148 (one-sided). This result indicates that past vaccination behaviour during the H1N1 pandemic is not related to the willingness to get vaccinated during a future pandemic. Hypothesis 1a does not receive support although one has to interpret this finding with caution due to the very small N of vaccinated people. In contrast, receiving vaccination against the seasonal flu is significantly associated with the future acceptance of pandemic vaccination (Chi-Square=16.045; df=1; P<0.001) and Hypothesis 1b is clearly supported. 76.2% of people who usually or at least in some years get vaccinated against the annual influenza virus would also seek vaccination in case of a new pandemic. In contrast, only 29.9% of respondents who normally do not get immunised against the seasonal flu would change their mind during a pandemic outbreak.