General Flu Information, Information for Health Care Providers, and Where to Get a Flu Shot

Flu Fact Sheet

Influenza or “flu” is an infection of the nose, throat, and lungs caused by the influenza virus. It is not the upset stomach popularly called “stomach flu”. The flu is highly contagious and is spread from person to person through the air by coughing or sneezing. It is also spread by direct contact with infected people. Flu symptoms usually begin 1 to 4 days after being infected with the flu virus. Symptoms include chills, fever, cough, headache, muscle aches, sore throat, runny nose, and fatigue. Influenza can be a serious illness that causes severe complications such as pneumonia, bronchitis, and sinus infections. Thousands of deaths each year are caused by influenza.

There are two major types of influenza viruses:

  • Type A generally causes the most severe symptoms
  • Type B causes symptoms similar to Type A, but usually less severe.

The most important way to prevent influenza is vaccination. There is a new vaccine every year because the flu viruses change from year to year. The shot you received last year won’t protect you this year. People at higher risk for complications should get the flu vaccine each year. The best time is between October and mid-November. However, the flu vaccine can be given at any time during the influenza season.

Adobe Acrobat Reader is required to read the following PDF files. If you do not have Acrobat Reader, Click Here to download.

Get a Flu Shot

Flu Facts

Flu Surveillance and Data

Information for Health Care Providers

Other Flu Websites



Contact Us

Center for Immunization Email:
MDH.IZInfo@maryland.gov