How severe is illness associated with novel H1N1 flu virus?
Illness with the new H1N1 virus has ranged from mild to severe. While most people who have been sick have recovered without needing medical treatment, hospitalizations and deaths from infection with this virus have occurred. In seasonal flu, certain people are at “high risk” of serious complications. This includes people 65 years and older, children younger than five years old, pregnant women, and people of any age with certain chronic medical conditions. About 70% of people who have been hospitalized with this novel H1N1 virus have had one or more medical conditions previously recognized as placing people at “high risk” of serious seasonal flu-related complications. This includes pregnancy, diabetes, heart disease, asthma, and kidney disease. One thing that appears to be different from seasonal influenza is that adults older than 64 years do not yet appear to be at increased risk of novel H1N1-related complications thus far. CDC laboratory studies have shown that no children and very