'Tis the season to be jolly -- as long as you don't come down with the flu.

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"We are early in the season but we are beginning to see a ramp-up in respiratory illnesses in general, and the flu in particular, at this point," said Dr. Ed Lifshitz, medical director of the Communicable Disease Service for New Jersey's health department.

He said the department keeps an eye on flu activity in a number of different ways, "including having what we call sentinel providers, who are physicians and other clinicians out there who let us know what they're seeing in their offices."

Health officials also take samples, monitor the absences of schoolchildren, and keep statistics for emergency medical visits.

Lifshitz stressed that not everyone who is sick has influenza, because there are several respiratory illnesses circulating across the Garden State.

When will flu season hit its peak?

"It's unpredictable, meaning exactly how this flu season will go, when it will peak, how severe it will be, all those sorts of things we can't answer," said Lifshitz. "We do see flu peaks that happen in the January-February region, but we've seen them as early as November and as late as into March, so we don't know."

He recommended that everyone who hasn't done so already get a flu shot.

"Every year, thousands of people in New Jersey get sick from the flu; some die, including young and otherwise healthy people," Lifshitz said. "It's not too late to vaccinate -- now is the best time you could vaccinate going forward."