What sort of flu season is expected this year?

Public Health officials are preparing the nation for what promises to be a challenging double whammy of a flu season with two types of flu in circulation — the novel H1N1, or so-called swine flu, and the usual seasonal influenza — each entailing its own vaccine, targeted at different sets of high-risk groups.

What is influenza (also called flu)?

The flu is a respiratory illness caused by influenza viruses that can be passed from person to person. It can cause mild to severe illness and at times can lead to death. Some people, such as older people, young children, pregnant women and those with certain health conditions (such as asthma, diabetes, or heart disease), are at increased risk for serious complications, including death, from influenza illness.

What is novel H1N1?

The novel or 2009 pandemic H1N1 (referred to as "swine flu" early on) is a new influenza virus causing illness in people. This new virus was first identified in people in the United States in April 2009. Since then, this virus has been spreading from person-to-person worldwide in much the same way that regular seasonal influenza viruses spread. Because H1N1 infections are occurring in many countries at the same time, it has been deemed as the 2009 pandemic influenza.

Why is H1N1 different from the seasonal flu?

Unlike seasonal flu, H1N1 has caused severe illness in the young and old, healthy and the chronically ill—all at an unusual time of the year.