Seasonal Influenza

Influenza, or "flu," is an infection of the nose, throat and lungs caused by the influenza virus. 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.

There are two major types of influenza viruses:
  • Type A, which generally causes more severe symptoms
  • Type B, which causes symptoms similar to Type A, but usually less severe

According to the Centers for Disease Control and Prevention, reducing the spread of respiratory illnesses, like flu, this fall and winter is more important than ever because of the COVID-19 pandemic.




Some symptoms of cold, flu and COVID-19 are similar, making it hard to tell the difference without diagnostic testing. Talk to your health care provider if you're experiencing symptoms and need guidance about what to be tested for.

Flu symptoms usually begin one to four days after being infected with the influenza virus. Symptoms include chills, fever, cough, headache, muscle aches, sore throat, runny nose and fatigue.

Flu can be a serious illness that causes severe complications such as pneumonia, bronchitis and sinus infections. Thousands of deaths each year are caused by flu.

According to the CDC, anyone can get sick with flu (even healthy people). Serious problems related to flu can happen at any age, but some people are at higher risk of developing serious flu-related complications if they get sick. This includes people 65 years and older, people of any age with certain chronic medical conditions (such as asthma, diabetes or heart disease), pregnant women and children younger than five years old, but especially those younger than two years old.



Get Your Flu Shot

The most important way to prevent flu is to get a flu shot. There is a new vaccine every year because the influenza viruses change from year to year. People at higher risk for complications should get the flu vaccine every year.

The best time to get vaccinated is between September and October. However, the flu vaccine can be given at any tme during the flu season.

Talk to your health care provider about which flu shot is right for you and your family members. Marylanders can also visit marylandvax.org to schedule an appointment with their local health department's flu vaccination clinic.



More Resources

Maryland Department of Health Flu Surveillance Information