ABSTRACT
Influenza virus is one of the most efficient and infectious pathogens known. The symptoms that the virus elicits in the human respiratory tract are ideally suited for the promulgation and propagation of the disease that it causes. Influenza viruses have the ability to cause infection on a global scale in all age groups (Woodson, 2005). In addition to the highly transmissible nature of influenza, the virus can change its antigenic structure, resulting in novel subtypes that have never circulated in the human population. The emergence of a novel influenza viral subtype is one of the factors necessary for the development of an influenza pandemic. The extreme mutability of the RNA-based influenza virus makes the emergence of a novel strain much more likely than with other disease-causing organisms, such as bacteria or
4.1 Introduction ..................................................................................................... 73 4.2 Uncomplicated Seasonal Influenza ................................................................. 74 4.3 Differential Diagnosis ..................................................................................... 78 4.4 Common Complications of Influenza ............................................................. 81
4.4.1 Less Common Complications of Influenza ......................................... 82 4.5 Avian Influenza Infection in Humans: Implications
for the Coming Pandemic ............................................................................... 82 4.5.1 Clinical Presentation of H5N1 in Humans..........................................84
