For the above reasons, the World Health Organization (WHO), United Kingdom Department of Health (DoH) [8] , United States Centers for Disease Control and Prevention (CDC), other healthcare professional organizations and many countries' government agencies [1, 9, 10] strongly recommend the annual seasonal influenza vaccination of HCWs. However, studies suggest that influenza vaccine uptake in HCWs is often low worldwide [11] [12] [13] [14] . For example, the overall seasonal vaccination rate in England for HCWs was 26 . 4% for the 2009/2010 season [15] . Nurses, as the group having the most patient contact, are more reluctant to be vaccinated than other HCWs [16] [17] [18] [19] [20] [21] [22] [23] .