NEW YORK (CBSNewYork) -- Tis the season for the flu.
There are some concerns that this season could be worse than others.
As CBS2's Alice Gainer reported, several states are already reporting more cases than usual.
The virus is now widespread in four states.
The Centers for Disease Control says confirmed cases are at just over 7,000. That's more than double what they were at this time last year.
This year's flu shot is the same one used in Australia's recent flu season when it was only 10-percent effective.
"Lot's of different strains and it's changing all the time, and so by the time we pick a version of the virus to make into a vaccine and put into production might take 6 to 8 months and in that time, the virus might change," Infectious Disease Researcher, The Broad Institute, Dr. Pardis Sabeti said.
According to the CDC, on average a flu vaccine is 37 percent effective. Last year's vaccine was 42 percent effective.
The New York City Department said flu activity in the area is low, but increasing.
Dr. Len Horovitz, a pulmonologist at Lenox Hill Hospital echoes that.
"So far there aren't that many cases here in the New York area of influenza, but there will be," he said.
He said just because the vaccine may be less effective, doesn't mean you shouldn't get it.
"Anything is better than zero," he said, "Even if you have a case of the flu, and you've been vaccinated, it'll be less severe and less duration of symptoms."
He also added that it's not too late to get the shot and to make sure you're washing your hands.
This season, only injectable flu vaccines are recommended.
According to the CDC, flu activity most commonly peaks in the U.S. between December and February.
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