Abstract
Influenza viruses are orthomyxoviruses belonging to three distinc genera, Influenzavirus A, B e C. They are enveloped viruses with genome consisting of 8 segments of single-stranded negative-sense RNA for influenza viruses A and B, and 7 for influenza C. The infection may cause typical symptoms of influenza, or severe acute respiratory syndrome, being an important cause of morbidity and m…