Analyzing the H1N1 flu epidemic

Health experts say: Flu viruses are hard to predict.

A year after most of us started hearing about the H1N1 virus; health officials are still counting up the flu cases and tracking the public’s reaction. WHYY asked how the new flu changes things for the future.

In Pennsylvania, more people got the flu in 2009 compared to any year in recent history. Children and young adults were hardest hit. All but five confirmed cases statewide were H1N1.

There were fewer hospitalizations and deaths than predicted. It’s not clear why. Experts say it might be that the new flu gave a pass to many seniors, who are more susceptible to flu complications. Marla Gold is Dean of the Drexel University School of Public Health.

Gold: When people say: ‘It wasn’t so bad, there were so many deaths as you said there would be.’ In public health, we say to you: ‘There weren’t so many deaths because people got vaccinated and also practiced really good hygiene with hand washing and understood in protecting yourself from disease you are protecting others about disease.’

Last year, many more people than usual got the flu vaccine, both types, for protection against the seasonal and H1N1 strains. This fall, there will be just one flu shot designed to ward off H1N1 and the more common viruses.

Dr. Stephen Ostroff leads the Pennsylvania Bureau of Epidemiology.

Ostroff: So looking back from October 1st to the present, in the entire state of Pennsylvania, there have only been five recorded, confirmed cases of influenza due to the seasonal strains, everything else that we’ve seen has been due to the pandemic influenza.

There’s lots of speculation about why the seasonal flu went on holiday this winter. But Ostroff says you have to keep in mind that flu strains compete. H1N1 may have crowded out the seasonal strains. Experts are waiting to see if the seasonal flu will re-emerge.