An unusual strain of the Flu is popping up this flu season: H1N1, known as swine flu, has hit the Central Coast hard, said the health department.

The Monterey County Health Department says there is no doubt that H1N1 is the most common flu people are catching right now, according to providers reporting the incidents to the department, but the area has not yet reached outbreak levels like in other areas of the country.

"We are in the height of flu season," said Judy Honegger, an obstetrician affiliated with Salinas Valley Medical Healthcare System who has observed a rise in influenza firsthand. "I have a lot of patients right now coming in with respiratory illnesses suggestive of the flu, so it's on the rise."

It's not unusual for the flu to hit a peak during this time of year. Doctors say that during the holiday season it's colder outside, so people are staying inside where illness can spread rapidly. Also, the holidays are prime season for socializing and gathering with other people where germs can spread. People are also  traveling long distances to be with family, where contagious illnesses like the flu can spread like wildfire like on planes or trains.

However, the Monterey County Health Department says the increase in cases is moving faster than usual.

"I can tell you that in Thanksgiving there has been an increase in the number of influenza illnesses that have been reported to us by providers and it's a 50 percent increase," said Dr. Edward Moreno, Director of Public Health for the Monterey County Health Department.

Even more unusual is that the H1N1 strain, or swine flu, is popping up.

"Nearly all of the influenza that is being test(ed) is influenza A and of that is the H1N1 that started the pandemic in 2009," said Moreno.

Monterey County Health Department said there had been one report of a young person that had to go to the Intensive Care Unit due to influenza.

H1N1 is a flu strain that doesn't just make people older than 65 and infants vulnerable to serious illness; but it attacks young, healthy people, too. The good news is the H1N1 is a strain that the flu shot can fight against.