The flu, also called influenza1, is a respiratory infection caused by viruses. Each year, millions of Americans get sick with the flu. Sometimes it causes mild illness. But it can also be serious or even deadly, especially for people over 65, newborn babies, and people with certain chronic illnesses.
What causes the flu?
Why should people get vaccinated against flu?
Influenza is a potentially serious disease that can lead to hospitalization and sometimes even death. Every flu season is different, and influenza infection can affect people differently, but millions of people get flu every year, hundreds of thousands of people are hospitalized and thousands to tens of thousands of people die from flu-related causes every year. An annual seasonal flu vaccine is the best way to help protect against flu. Vaccination has been shown to have many benefits including reducing the risk of flu illnesses, hospitalizations and even the risk of flu-related death in children. Jay Harold put together this post, “Flu Vaccination 2020-21: Things to Know” to provide useful information about the flu.
How do flu vaccines work?
Flu vaccines cause antibodies to develop in the body about two weeks after vaccination. These antibodies provide protection against infection with the viruses that are used to make the vaccine.
The seasonal flu vaccine2 protects against the influenza viruses that research indicates will be most common during the upcoming season. Most flu vaccines in the United States protect against four different flu viruses (“quadrivalent”); an influenza A (H1N1) virus, an influenza A (H3N2) virus, and two influenza B viruses. There are also some flu vaccines that protect against three different flu viruses (“trivalent”); an influenza A (H1N1) virus, an influenza A (H3N2) virus, and one influenza B virus. Two of the trivalent vaccines are designed specifically for people 65 and older to create a stronger immune response.
What kinds of flu vaccines are available?
CDC recommends use of any licensed, age-appropriate influenza vaccine during the 2020-2021 influenza season, including inactivated influenza vaccine [IIV], recombinant influenza vaccine [RIV], or live attenuated influenza vaccine (LAIV). No preference is expressed for any influenza vaccine over another. Both trivalent (three-ingredient) and quadrivalent (four-ingredient) influenza vaccines will be available.
Trivalent flu vaccines include:
A trivalent flu shot made using an adjuvant (an ingredient that helps create a stronger immune response), approved for people 65 years of age and older.
Quadrivalent flu vaccines include:
Standard-dose quadrivalent influenza shots that are manufactured using virus grown in eggs. These include Afluria Quadrivalent, Fluarix Quadrivalent, FluLaval Quadrivalent, and Fluzone Quadrivalent. Different influenza shots are licensed for different age groups. Some are licensed for children as young as 6 months of age. Most influenza shots are given in an arm muscle with a needle. One quadrivalent influenza shot (Afluria Quadrivalent) can be given either with a needle (for people aged 6 months and older) or with a jet injector (for people aged 18 through 64 years only).
A quadrivalent cell-based influenza shot (Flucelvax Quadrivalent) containing virus grown in cell culture, which is licensed for people 4 years and older. This season, all four of the vaccine viruses used in Flucelvax have been grown in cells, making the vaccine totally egg-free.
Recombinant quadrivalent influenza shot (Flublok Quadrivalent), an egg-free vaccine, approved for people 18 years and older.
A quadrivalent flu shot using an adjuvant (an ingredient that helps create a stronger immune response), approved for people 65 years of age and older.
A quadrivalent high-dose influenza vaccine (Fluzone High-Dose), licensed for people 65 years and older.
There are many flu vaccine options to choose from, but the most important thing is for all people 6 months and older to get a flu vaccine every year. If you have questions about which vaccine is best for you, talk to your doctor or other health care professional. More information on approved flu vaccines for the 2020-2021 flu season, and age indications for each vaccine are available in CDC’s Table: U.S. Influenza Vaccine Products for the 2020-2021 Season.
Flu Vaccination
Why should people get vaccinated against flu?
Influenza is a potentially serious disease that can lead to hospitalization and sometimes even death. Every flu season is different, and influenza infection can affect people differently, but millions of people get flu every year, hundreds of thousands of people are hospitalized and thousands to tens of thousands of people die from flu-related causes every year. An annual seasonal flu vaccine is the best way to help protect against flu. Vaccination has been shown to have many benefits including reducing the risk of flu illnesses, hospitalizations and even the risk of flu-related death in children.
How do flu vaccines work?
Flu vaccines cause antibodies to develop in the body about two weeks after vaccination. These antibodies provide protection against infection with the viruses that are used to make the vaccine.
The seasonal flu vaccine protects against the influenza viruses that research indicates will be most common during the upcoming season. Most flu vaccines in the United States protect against four different flu viruses (“quadrivalent”); an influenza A (H1N1) virus, an influenza A (H3N2) virus, and two influenza B viruses. There are also some flu vaccines that protect against three different flu viruses (“trivalent”); an influenza A (H1N1) virus, an influenza A (H3N2) virus, and one influenza B virus. Two of the trivalent vaccines are designed specifically for people 65 and older to create a stronger immune response.
What kinds of flu vaccines are available?
CDC recommends use of any licensed, age-appropriate influenza vaccine during the 2020-2021 influenza season, including inactivated influenza vaccine [IIV], recombinant influenza vaccine [RIV], or live attenuated influenza vaccine (LAIV). No preference is expressed for any influenza vaccine over another. Both trivalent (three-ingredient) and quadrivalent (four-ingredient) influenza vaccines will be available.
Trivalent flu vaccines include:
A trivalent flu shot made using an adjuvant (an ingredient that helps create a stronger immune response), approved for people 65 years of age and older.
Quadrivalent flu vaccines include:
Standard-dose quadrivalent influenza shots that are manufactured using virus grown in eggs. These include Afluria Quadrivalent, Fluarix Quadrivalent, FluLaval Quadrivalent, and Fluzone Quadrivalent. Different influenza shots are licensed for different age groups. Some are licensed for children as young as 6 months of age. Most influenza shots are given in an arm muscle with a needle. One quadrivalent influenza shot (Afluria Quadrivalent) can be given either with a needle (for people aged 6 months and older) or with a jet injector (for people aged 18 through 64 years only).
A quadrivalent cell-based influenza shot (Flucelvax Quadrivalent) containing virus grown in cell culture, which is licensed for people 4 years and older. This season, all four of the vaccine viruses used in Flucelvax have been grown in cells, making the vaccine totally egg-free.
Recombinant quadrivalent influenza shot (Flublok Quadrivalent), an egg-free vaccine, approved for people 18 years and older.
A quadrivalent flu shot using an adjuvant (an ingredient that helps create a stronger immune response), approved for people 65 years of age and older.
A quadrivalent high-dose influenza vaccine (Fluzone High-Dose), licensed for people 65 years and older.
There are many flu vaccine options to choose from, but the most important thing is for all people 6 months and older to get a flu vaccine every year. If you have questions about which vaccine is best for you, talk to your doctor or other health care professional. More information on approved flu vaccines for the 2020-2021 flu season, and age indications for each vaccine are available in CDC’s Table: U.S. Influenza Vaccine Products for the 2020-2021 Season.
Are any of the available flu vaccines recommended over others?
For the 2020-2021 flu season, the Advisory Committee on Immunization Practices (ACIP) recommends annual influenza (flu) vaccination for everyone 6 months and older with any licensed, influenza vaccine that is appropriate for the recipient’s age and health status, including inactivated influenza vaccine (IIV), recombinant influenza vaccine (RIV), or live attenuated nasal spray influenza vaccine (LAIV4) with no preference expressed for any one vaccine over another.
There are many vaccine options to choose from, but the most important thing is for all people 6 months and older to get a flu vaccine every year. If you have questions about which vaccine is best for you, talk to your doctor or other health care professional.
Who Should Not Be Vaccinated?
Different influenza (flu) vaccines are approved for use in different age groups. In addition, some vaccines are not recommended for certain groups of people. Factors that can determine a person’s suitability for vaccination, or vaccination with a particular vaccine, include a person’s age, health (current and past) and any allergies to flu vaccine or its components. For more information, visit Who Should and Who Should NOT get a Flu Vaccine.
When should I get vaccinated?
You should get a flu vaccine before flu viruses begin spreading in your community, since it takes about two weeks after vaccination for antibodies to develop in the body and provide protection against flu. Make plans to get vaccinated early in fall, before flu season begins. CDC recommends that people get a flu vaccine by the end of October. However, getting vaccinated early (for example, in July or August) is likely to be associated with reduced protection against flu infection later in the flu season, particularly among older adults. Vaccination should continue to be offered throughout the flu season, even into January or later. Children who need two doses of vaccine to be protected should start the vaccination process sooner, because the two doses must be given at least four weeks apart.
Where can I get a flu vaccine?
VaccineFinder
Find flu vaccines in your area. Everyone 6 months of age and older needs a flu vaccine.
Flu vaccines are offered in many doctor’s offices, clinics, health departments, pharmacies and college health centers, as well as by many employers, and even in some schools.
Even if you don’t have a regular doctor or nurse, you can get a flu vaccine somewhere else, like a health department, pharmacy, urgent care clinic, and often your school, college health center, or workplace.
Visit the HealthMap Vaccine Finderexternal icon to locate where you can get a flu vaccine.
Why do I need a flu vaccine every year?
A flu vaccine is needed every season for two reasons. First, a person’s immune protection from vaccination declines over time, so an annual vaccine is needed for optimal protection. Second, because flu viruses are constantly changing, flu vaccines may be updated from one season to the next to protect against the viruses that research suggests may be most common during the upcoming flu season. For the best protection, everyone 6 months and older should get vaccinated annually.
Does flu vaccine work right away?
No. It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against influenza virus infection. That’s why it’s best to get vaccinated before influenza viruses start to spread in your community.
