Bird Flu Alarm



Understanding Avian Influenza

A New influenza Virus: How It Could Cause A Pandemic


Influenza A and influenza B are 2 of the 3 types of influenza viruses associated with annual outbreaks and epidemics of influenza. The third type, influenza C, causes only mild disease and has not been associated with widespread epidemics or pandemics. Annual outbreaks of influenza are due to minor changes in the surface proteins of the viruses that enable the viruses to evade the immunity humans have developed after previous infections with the viruses or in response to vaccinations.

Only influenza A virus can cause pandemics. When a major change in either 1 or both of their surface proteins occurs spontaneously, no one will have partial or full immunity against infection because it is a completely new virus. If this new virus also has the capacity to spread from person-to-person, then a pandemic is most likely to occur.

Understanding Avian Influenza