Flu season is officially underway.
Michigan Department of Community Health officials said today that 12 influenza cases are the first seasonal flu reports they have confirmed in Michigan during the 2012-2013 season.
They said the illnesses occurred in children and adults in lower Michigan.
Two people were hospitalized. Nine cases have been confirmed as influenza B viruses, two as influenza A (H3N2) virus and one as influenza A (H1N1) 2009 virus.
Officials say it's too early to tell what influenza viruses will circulate this influenza season or how severe it might be.
Officials recommend flu shots as a way to prevent the disease.
Michigan's flu activity is listed as "sporadic," the lowest of four levels of influenza activity.
Several years ago I interviewed Peter Palese, a microbiologist and Chair of the Department of Microbiology at the Mount Sinai Medical Center in New York City.
They were researching why the flu virus spreads in cold weather.
They found that once the flu virus is airborne, it survives longer in cold air and low humidity. It doesn't survive as long in higher temperatures and higher humidity.
Palese said age old maternal advice held up in their research:
They tested guinea pigs infected with the flu virus - and found that the animals are more contagious when they're in a colder environment. They believe that's because their bodies don't get rid of the virus as fast in cold temperatures...
"So that makes sense when your grandmother told you 'don't go out when it's cold, and stay warm and you might get the flu,' she was probably right," said Palese.