How Dangerous is Influenza A H1N1?
Seasonal influenza causes 30,000-40,000 deaths each year in the United States and 250,000-500,000 deaths each year worldwide, mostly in those who are very young, old, or weak (e.g., with chronic medical illnesses or suppressed immune systems). Thus, the fact that approximately 50 people worldwide have died of the current Influenza A H1N1 outbreak does not in itself mean that this new virus is unusually dangerous. Perhaps the most compelling comparison when considering the current Influenza A H1N1 outbreak is whether this new virus is behaving more like seasonal influenza vs. the highly feared avian influenza (bird flu) that has been in the news over the past 4-5 years. The latter virus has not demonstrated significant person-to-person spread, but it has proven to be highly lethal with well over 50% of those with the disease dying from it. So, how does the Influenza A H1N1 virus compare to seasonal influenza versus avian influenza in terms of severity or lethality? Initial news reports
