A busier than normal flu season has led to an uptick in patients at emergency rooms and doctors offices across the city. NY1's Roger Clark filed the following report.

You don't have to remind Dr. Nora Esteban of the Childrens Hospital at Montefiore in the Bronx that the flu season has arrived.

"We are seeing three times the number of patients that came with flu symptoms last year. And in fact, 40 percent that are presented to the emergency room actually are flu positive at this point," Esteban said.

New York City and 24 states are reporting high levels of flu activity according to the Centers for Disease Control and Prevention's latest flu advisory report. That's down from 29 states the previous week. But the number of states reporting widespread activity increased to 47 from 40.

The flu usually peaks in mid-winter, but got off to an early start this season. On a conference call Friday, CDC Director Thomas Frieden talked about how effective this season's flu vaccine is.

"We found the overall vaccine effectiveness to be 62 percent. That means if that if you got vaccinated you were about 60 percent less likely to get the flu that required you to go to your doctor," Frieden said.

Dr. Frieden says the vaccine is far from perfect, but it is still by far the best tool they have to prevent the flu. Mayor Michael Bloomberg agreed.

"You should still get a flu shot. Number two, if you get the flu, don't go to the hospital. It's not life threatening generally, you're likely to infect other people, and there are lots of germs in hospitals, because that's where sick people go, so if you could avoid hospitals that would be great," Bloomberg said.

However, officials say people with severe symptoms should see a doctor. They may be given antiviral drugs or other medications to ease symptoms. Basic symptoms can include fever, cough, runny nose, head and body aches and fatigue. Some people also suffer vomiting and diarrhea, and some develop pneumonia or other severe complications.

There are of course some precautions you can take in addition to getting the vaccine.

"Washing your hands or using disinfectant gels are very important, and the third precaution is if someone has a cough they should be covering their mouth," Esteban recommended.

For more information on the flu, visit flu.gov.