The influenza virus is already making its way through the Southern Hemisphere and the good news is the strains of the virus that are showing up are the same strains in this year's vaccine.
Dr. Paul Glezen with Baylor College of Medicine says there are three viruses this year — influenza B, H1N1 and H3N2.
"There's a mix of viruses and so far we haven't seen any new viruses appear. In other words, the viruses that are circulating are covered by the vaccine. So the important thing now is for people to take the opportunity to get the vaccine as soon as possible."
Immunity to the flu does not persist, so even though this year's vaccine is the same as last year's, Glezen says people who got the shot last time around still need to be vaccinated again. And for those folks who think they'll never get the flu, Glezen points out it's the most common cause of acute respiratory illness every winter.
"Sometimes we escape exposure for a few years and we think we're invulnerable, you know. But the fact is it will catch up with you."
The flu vaccine, which can be administered through an injection or a nasal spray, is available to everyone over the age of six months.