Influenza (Flu) Information

Everyone 6 months of age and older should get a flu vaccine. Getting the vaccine is especially important for certain people who are at greater risk of serious illness and death from flu. They include:

• Young children
• Older adults
• People who are pregnant
• People with chronic health conditions including heart, lung, or kidney diseases or those with conditions that weaken their immune systems like diabetes
• Caretakers who live or work with patients who are at a high risk for developing flu-related complications
• Health care workers
• Family and caregivers of young children, especially infants

The protection provided by a flu vaccine varies from season to season and depends in part on the age and health status of the person getting the vaccine and the similarity or “match” between the viruses in the vaccine and those in circulation. During years when the flu vaccine match is good, the vaccine reduces the risk of flu illness by between 40% and 60% among the overall population, according to recent studies by the CDC.

The benefits of flu vaccination will vary, depending on factors like the characteristics of the person being vaccinated (ex. health or age) what influenza viruses are circulating that season and, potentially, which type of flu vaccine was used. For more information from the CDC, visit the Vaccine Effectiveness website.

The flu vaccine is safe.

In very rare cases, individuals may experience an allergic reaction to the shot. Signs of serious allergic reaction can include breathing problems, hoarseness or wheezing, hives, paleness, weakness, a fast heartbeat, or dizziness. If a reaction does occur, it is usually within a few minutes to a few hours after receiving the shot. These reactions can occur among persons who are allergic to an ingredient in the vaccine, such as egg protein or other ingredients. While severe reactions are uncommon, people receiving vaccinations should let their healthcare provider know if there's a history of allergy or severe reaction to influenza vaccine or any part of flu vaccine.

Flu vaccine side effects are generally mild and go away on their own within a few days. Some side effects that may occur from a flu shot include soreness, redness, and/or swelling where the shot was given, headache (low grade), fever, nausea, muscle aches, and fatigue.

There are several reasons why someone might get flu symptoms, even after they have been vaccinated against flu.

Some people can become ill from other respiratory viruses besides flu such as rhinoviruses, which are associated with the common cold, cause symptoms similar to flu, and also spread and cause illness during the flu season. The flu vaccine only protects against flu, not other illnesses.

It's possible to be exposed to flu viruses, which cause flu, shortly before getting vaccinated or during the two-week period after vaccination that it takes the body to develop immune protection. This exposure may result in a person becoming ill with flu before protection from vaccination takes effect.

Some people may experience flu symptoms despite getting vaccinated is that they may have been exposed to a flu virus that is very different from the viruses the vaccine is designed to protect against. The ability of a flu vaccine to protect a person depends largely on the similarity or “match” between the viruses selected to make the vaccine and those spreading and causing illness. There are many different flu viruses that spread and cause illness among people. View more information from the CDC on influenza viruses.

Flu vaccines vary in effectiveness and some people who get vaccinated still get sick. When that happens, though vaccination has been shown in several studies to reduce severity of illness in those people who get vaccinated but still get sick.

In addition to the regular flu shot, which is approved for all adults, high-dose flu vaccines were developed specially for those 65 and older. Contact a healthcare provider to determine if a high-dose vaccination is appropriate. 

Flu shots are covered by most major insurance providers. To find vaccines that do not require insurance or copay, please use the flu map.

Influenza (Flu) and COVID-19 are contagious respiratory illnesses, caused by different virus strains. COVID-19 is caused by infection from coronavirus (called SARS-CoV-2) and flu is caused by infection with influenza viruses. Some of the symptoms of flu and COVID-19 are similar, so it may be hard to tell the difference between them based on symptoms alone, and testing may be needed to help confirm a diagnosis.

For more information please visit the H5N1 (Bird Flu) information page

• Wash your hands often, with soap and water or alcohol-based hand sanitizers
• Avoid people who are sick. Stay home from work and school when you’re sick
• Keep your distance from others if you’re sick
• Cover your mouth and nose with a tissue when coughing or sneezing, then throw it away immediately
• If you don't have a tissue, cough or sneeze into your upper sleeve, not your hands
• Avoid touching your eyes, nose, or mouth after touching any objects or surfaces that might be contaminated

Most people recover from the flu in a few days or weeks.

• Get plenty of rest
• Drink a lot of liquids
• Avoid alcohol and tobacco
• Take appropriate medications to relieve the symptoms
• Never give aspirin to children or teenagers who have flu-like symptoms, especially fever, without consulting a healthcare professional

For those at risk from complications, consult a healthcare provider right away at the onset of flu-like symptoms. At-risk groups include people 65 or older, people with chronic medical conditions, people who are pregnant, and children under 2 years old. 

• COVID, Flu, RSV Dashboard
  
  
• 2022-2023 Seasonal Flu Data(PDF, 244KB)
• 2021-2022 Seasonal Flu Data(PDF, 324KB)
• 2020-2021 Seasonal Flu Data(PDF, 217KB)
• 2019-2020 Seasonal Flu Data(PDF, 258KB)
• 2018-2019 Seasonal Flu Data(PDF, 288KB)