More properly known as season influenza, flu symptoms include fever, cough, sore throat, stuffy-nose or head, body aches and chills.
Due to manufacturer shipping delays, the Tulsa Health Department is experiencing a temporary shortage of flu vaccine.
Preliminary reports show 19 people in Minnesota have been hospitalized because of the flu so far this season.
The flu season normally starts towards the end of the fall, but seasonal influenza is reportedly starting much earlier this year.
"No country can fight against influenza on its own", said Li Bin, deputy director of the National Health Commission (NHC), at the opening ceremony under the theme of "Know Flu, Prevent Flu and Beat Flu".More news: Abhishek Bachchan wishes his Principessa on Bday with an unseen pic
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Getting the flu shot provides protection in two ways, Person said.
Some elderly may not have as strong an immune reaction to the vaccine as others and it also helps protect infants and those who are medically fragile and can not get a flu shot. Individuals are encouraged to check vaccine availability at their primary care provider or pharmacy.
Influenza can cause mild to severe illness, and at times can lead to death.
Some people may have vomiting and diarrhea, though this is more common in children than adults.
In addition to getting vaccinated, people can take steps to avoid getting or spreading the flu.