As flu season approaches, many people start to consider getting a flu vaccine to protect themselves and their loved ones. But what is the flu vaccine, and how does it work?
We’ll provide an overview of the flu vaccine, including what it is, how it’s made, who should get it, and what the benefits are. We’ll also address some common concerns and misconceptions about the flu vaccine, to help you make an informed decision about whether or not to get vaccinated. So whether you’re a seasoned pro or a first-timer, read on for everything you need to know about the flu vaccine.
Importance of Flu Vaccines
Getting the flu shot is crucial for both individual and public health. As social distancing measures are relaxed, experts anticipate a rise in flu cases, which could overwhelm the healthcare system in addition to the ongoing pandemic. Vaccination is especially important for vulnerable populations, including those over 65 years old, people with chronic conditions, caretakers, and essential workers. Even though the vaccine’s effectiveness lasts for about six months, getting it can reduce the severity of an illness. Ultimately, suppressing influenza through vaccination can prevent it from mutating and infecting more people. [1]
Universal Vaccination Recommendation
The National Institute of Allergy and Infectious Diseases (NIAID) recommends developing a universal flu vaccine that provides long-term protection against multiple subtypes of flu. This vaccine would eliminate the need for yearly updates and potentially protect against newly emerging flu strains, including those that could cause a pandemic. The NIAID is conducting research in three specific areas to advance universal influenza vaccine development, including improving knowledge of transmission natural history and pathogenesis of influenza infection, characterizing influenza immunity, and supporting the rational design of universal influenza vaccines. [3][4]
Influenza Vaccine Options
The Centers for Disease Control and Prevention recommends different influenza vaccine options for different age groups, including inactivated influenza vaccines, recombinant influenza vaccines, and live attenuated influenza vaccines. All flu vaccines available in the US for the 2022-2023 season are quadrivalent vaccines designed to protect against four different flu viruses. It is important to speak to a healthcare professional to determine the best option for each individual. [5][6]
Preference for Vaccines for People 65 and Older
For people 65 years and older, three flu vaccines are recommended over standard-dose unadjuvanted flu vaccines during the 2022-2023 flu season: Fluzone High-Dose Quadrivalent vaccine, Flublok Quadrivalent recombinant flu vaccine, and Fluad Quadrivalent adjuvanted flu vaccine. These vaccines contain more antigen than standard-dose vaccines, which can create a stronger immune response. It is important for older adults to receive the vaccine to prevent serious flu complications. [7][8]
Available Quadrivalent Flu Vaccines
The available quadrivalent flu vaccines in the United States include AFLURIA Quadrivalent, Fluarix Quadrivalent, FluLaval Quadrivalent, Flucelvax Quadrivalent, Fluzone Quadrivalent, and FluMist Quadrivalent. These vaccines are designed to protect against four different flu viruses, including two influenza A viruses and two influenza B viruses. All flu vaccines in the US are quadrivalent, with different vaccines approved for different age groups. The safety profile of these vaccines is similar to seasonal flu vaccines made to protect against three viruses, with mostly mild side effects. [9][10]
Standard-Dose Flu Shots
Standard-dose flu shots are a common option for influenza vaccination. These vaccines are manufactured using virus grown in eggs and are available in several different brands, including Afluria Quadrivalent, Fluarix Quadrivalent, FluLaval Quadrivalent, and Fluzone Quadrivalent. These vaccines are approved for use in children as young as 6 months. Most flu shots are given in the arm (muscle) with a needle. Afluria Quadrivalent can be given either with a needle (for people 6 months and older) or with a jet injector (for people 18 through 64 years only). [11][12]
Cell-Based Flu Shots
The Flucelvax Quadrivalent is a cell-based flu vaccine prepared in cultured mammalian cells instead of eggs. It offers improved protection against flu-related hospitalizations and is licensed for use in people 6 months and older. Cell-based vaccine production does not require chicken eggs, making it independent of egg supply and adaptive changes caused by egg-based manufacturing. Its side effects are mild and temporary, including injection site pain, erythema, headache, fatigue, and myalgia. It is available for the 2022-2023 flu season and has been approved by the FDA for use in the United States. [13][14]
Egg-Based High Dose Flu Shots
The egg-based high-dose flu shot, Fluzone High-Dose Quadrivalent, is approved for people 65 years and older. This vaccine contains four times the antigen of other standard-dose inactivated flu vaccines to create a stronger immune response. However, the higher amount of antigen may also result in more side effects such as arm soreness, fever, and body aches. It is important to speak to a healthcare provider to determine if this vaccine is the best option for individual needs. [15][16]
Egg-Based Live Attenuated Flu Nasal Spray
The egg-based live attenuated flu nasal spray vaccine protects against four flu viruses and is approved for healthy individuals aged 2-49 years old. However, it is not recommended for individuals with certain medical conditions, including those with weakened immune systems, pregnant individuals, and children under 2 or over 17 who are taking aspirin or salicylate-containing medication. Side effects include a runny or stuffy nose, loss of appetite, and headache. The vaccine virus is weakened and cannot grow inside the body, but vaccinated children may shed the virus for a few days after vaccination. [17][18]
Vaccination for Special Populations
Vaccination is important for special populations, including pregnant women, older adults, and those with pre-existing medical conditions. The flu vaccine is safe for pregnant women and can protect both the mother and baby. Older adults may benefit from a higher dose of the vaccine, and those with medical conditions such as asthma or diabetes should consult with their healthcare provider about the best vaccine option for them. Additionally, people with a history of severe allergic reactions to vaccines should discuss options with a healthcare provider before getting vaccinated. [19][20]
