What is the difference between influenza A, B and C?
There are three main influenza viruses; influenza A, influenza B and influenza C. Seasonal influenza is usually caused by influenza A and B viruses. Seasonal influenza occurs in Canada every year, generally during late fall and throughout the winter months. Influenza A In most years, influenza A viruses are the most common cause of annual influenza outbreaks. Influenza A may cause large pandemics with significant mortality in young persons. Influenza B Although less common, outbreaks of influenza B occasionally occur. Outbreaks of Influenza B are generally more localized and in any one year may be restricted to one region of the country. Influenza B typically produces milder symptoms than influenza A when it infects humans. Influenza B also mutates much more slowly than influenza A; however, it still mutates too quickly for a person to build a lasting immunity to it. Influenza C Influenza C causes mild disease in humans, and does not occur seasonally.
