Fever, muscle aches, chills and a sore throat; these are symptoms everyone has experienced at one point or another.
Luckily, they can sometimes be avoided with a flu vaccine.
"We're just getting into flu season and as the weather gets worse we'll see more and more of it," said Christine Schuyler, public health director for Chautauqua County.
There are simple ways to avoid the virus, Schuyler said, other than a flu shot.
"The main thing is a good handwashing, frequently, and being diligent about keeping surfaces clean like telephones, computer keyboards, doorknobs and things people are constantly touching," she said.
Flu viruses are always changing. Each year's flu vaccine is made to protect from viruses that are most likely to cause disease that year.
"So far, it's projected to be a typical flu season," Schuyler said. "Hopefully the vaccine is matched pretty well with the types of viruses we're seeing."
Schuyler said this year's flu season is not projected to be any worse than previous years.
"We had a pretty normal flu season last year," she said, adding that there have not been any confirmed cases of influenza in Chautauqua County yet this year.
The immunization also helps prevent spreading flu from person to person.
There are two types of the vaccine. Inactivated, which does not contain any live virus and is injected with a needle is what most people refer to as the "flu shot." The other is a live, attenuated (weakened) influenza vaccine which is sprayed into the nostrils.
Inactivated flu vaccine protects against three or four different influenza viruses. It takes about two weeks for protection to develop after the vaccination, and protection lasts several months to a year.
According to the U.S. Department of Health and Human Services, everyone 6 months and older should get a flu shot. Flu vaccine is recommended every year, while children 6 months through 8 years of age should get two doses the first year they get vaccinated.
Also, a "high-dose" flu vaccine is available for people 65 years of age and older.
A study conducted by the Centers for Disease Control and Prevention found that on average, 200,000 people in the U.S. are hospitalized each year for respiratory and cardiac-related illnesses associated with seasonal influenza virus infections.
"Stop at your local pharmacy or see your physician and get a flu shot," Schuyler said. "And, if you're sick, stay at home so you're not spreading things around."