Tool for Influenza Pandemic Risk Assessment (TIPRA) 2nd Edition

Overview

Influenza pandemics are unpredictable but recurring events that can have consequences on human health and economic well-being worldwide. An influenza pandemic occurs when an influenza A virus to which most humans have little or no existing immunity acquires the ability to cause sustained human-to-human transmission leading to community-wide outbreaks globally.

Influenza A viruses have a highly divergent gene constellation and are detected in a wide range of host species. In the field, virus transmission within and among animal species occurs frequently and viruses change by gene mutations and gene reassortment with the potential to create a virus capable of transmitting efficiently between humans. The emergence of the A(H1N1) 2009 influenza pandemic virus, animal-to-human transmission of A(H5N1), A(H7N9) and other animal influenza viruses highlight the importance of monitoring and assessing the potential risks of emerging influenza viruses to cause future pandemics.