A review on the clinical spectrum and natural history of human influenza
International Journal of Infectious Diseases, 07/19/2012
Punpanich W et al. – Clinical features and risk factors of A(H1N1)pdm09 are comparable to those of seasonal influenza. Emerging risk factors for severe disease with A(H1N1)pdm09 include morbid obesity, pregnancy, bacterial co–infections, and D222/N variants or 225G substitution of the viral genome.