Preventing seasonal flu: get vaccinated
The single best way to prevent the flu is to get a flu vaccine each season. Traditional flu vaccines that were made to protect against three different flu viruses (called “trivalent” vaccines) are available. In addition, this season, flu vaccines are made to protect against four different flu viruses (called “quadrivalent” vaccines), which are also available. The trivalent flu vaccine protects against two influenza A viruses and an influenza B virus. The Centers for Disease Control and Prevention does not recommend one flu vaccine over the other. The important thing is to get a flu vaccine every year.
Yearly flu vaccination should begin soon after flu vaccine is available, and ideally by October. However, getting vaccinated even later can be protective, as long as flu viruses are circulating. While seasonal influenza outbreaks can happen as early as October, most of the time influenza activity peaks in January or later. Since it takes about two weeks after vaccination for antibodies to develop in the body that protect against influenza virus infection, it is best that people get vaccinated so they are protected before influenza begins spreading in their community.
Everyone six months and older should get a flu vaccine each year. This recommendation has been in place since February 24, 2010 when CDC’s Advisory Committee on Immunization Practices (ACIP) voted for "universal" flu vaccination in the U.S. to expand protection against the flu to more people. While everyone should get a flu vaccine each flu season, it’s especially important that certain people get vaccinated either because they are at high risk of having serious flu-related complications or because they live with or care for people at high risk for developing flu-related complications.
- Children younger than five, but especially children younger than two years old
- Adults 65 years of age and older
- Pregnant women
- American Indians and Alaskan Natives seem to be at higher risk of flu complications
Additionally, people who have medical conditions including:
- Asthma (even if it’s controlled or mild)
- Neurological and neurodevelopmental conditions [including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy (seizure disorders), stroke, intellectual disability (mental retardation), moderate to severe developmental delay, muscular dystrophy, or spinal cord injury]
- Chronic lung disease (such as chronic obstructive pulmonary disease [COPD] and cystic fibrosis)
- Heart disease (such as congenital heart disease, congestive heart failure and coronary artery disease)
- Blood disorders (such as sickle cell disease)
- Endocrine disorders (such as diabetes mellitus)
- Kidney disorders
- Liver disorders
- Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders)
- Weakened immune system due to disease or medication (such as people with HIV or AIDS, or cancer, or those on chronic steroids)
- People younger than 19 years of age who are receiving long-term aspirin therapy
- People who are morbidly obese (Body Mass Index [BMI] of 40 or greater)
Who else should get vaccinated?
Some people should not be vaccinated without first consulting a physician. They include:
- People who have a severe allergy to chicken eggs.
- People who have had a severe reaction to an influenza vaccination in the past.
- Children younger than six months of age (influenza vaccine is not approved for use in this age group).
- People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.
- People with a history of Guillain-Barré Syndrome (a severe paralytic illness, also called GBS) that occurred after receiving influenza vaccine and who are not at risk for severe illness from influenza should generally not receive vaccine. Tell your doctor if you ever had Guillain-Barré Syndrome. Your doctor will help you decide whether the vaccine is recommended for you.