Grgic S, Skocibusic S, Celjuska-Tosev E, Nikolic J, Arapovic J, Kuzman I (2016) Different features of influenza A H1N1pdm09 virus infection among adults in 2009/10 and 2010/11. J Infect Dev Ctries 10:155–162. doi: 10.3855/jidc.6040