Buzz
As the winter season approaches, it's the perfect time for everyone, especially older adults, to update their flu and COVID vaccinations. If you're over 65, you might want to opt for a high-dose or adjuvanted flu shot, which are designed specifically for older adults and may offer better protection. However, if these options aren't available, the CDC assures that the regular flu shot is still a suitable choice.
What flu shots are recommended for older adults?
If you're 65 or older, the CDC suggests these three flu shots, if accessible:
A high-dose flu shot.
A recombinant flu shot, which is also egg-free.
An adjuvanted flu shot.
I'll explain what these terms mean and why these shots are considered more suitable for older adults. However, you don't need to fully understand all the differences to make an appointment at your local pharmacy. Simply ask if they have any of the vaccines listed above, and if so, opt for one of those rather than the regular flu shots.
What does 'high dose' mean, and why is it beneficial?
Vaccines work by introducing a small amount of antigen to your immune system. The immune system then recognizes the antigen and prepares to respond to it in the future; in many flu vaccines, the antigen is made up of a killed and fragmented influenza virus. (This is why the flu shot cannot give you the flu.)
As we age, our immune system may not react as strongly as it did in our younger years, so a regular flu vaccine might not trigger a strong enough immune response to be effective. One solution is to use more antigen, which is the premise behind the high-dose flu shot: it contains four times the amount of virus fragments compared to the regular version.
The side effects associated with the high-dose flu vaccine are a bit more frequent than those seen with the standard version. However, the types of side effects are the same as what anyone might experience from any flu shot. Like the regular flu vaccine, these side effects are typically not serious. According to the CDC, "The most common adverse events experienced during clinical studies were mild and temporary, including pain, redness at the injection site, headache, muscle aches, and malaise."
What does the term 'adjuvanted' refer to?
For older adults, instead of the high-dose flu vaccine, there is another enhanced option: an adjuvanted vaccine. This type of vaccine doesn’t use a higher dose of the antigen; rather, it contains an adjuvant—a substance that boosts the immune system's response. In this case, the adjuvant used is squalene oil, known as MF59.
Similar to the high-dose flu vaccine, the adjuvanted vaccine has slightly higher rates of side effects compared to the standard flu vaccine, though these are generally not severe. The CDC states, "The most common adverse events experienced during clinical studies were mild to moderate and temporary, including pain, redness at the injection site, headache, muscle aches, and malaise."
What is meant by a 'recombinant' flu shot?
The term 'recombinant' describes the method used to produce the virus particles for the vaccine. Traditionally, flu vaccines were made using chicken eggs. A newer option, the cell-culture-based vaccine, avoids the use of eggs. The recombinant vaccine represents a third approach.
According to the CDC, a recombinant vaccine does not involve using flu viruses in its creation. Instead, a segment of the flu virus's genetic material is introduced into another virus (hence 'recombinant,' meaning different genetic materials are combined). This virus is grown in cells, and the influenza virus protein is extracted and purified for use in the vaccine.
The recombinant vaccine is suitable for all age groups, not just older adults. It is particularly recommended for older adults because it contains a higher amount of antigen than standard flu vaccines and has been shown to be highly effective for this age group.
If I'm over 65, do I need a special flu shot?
The CDC states that any flu vaccine approved for your age group is fine. However, there are three flu vaccines that are specifically formulated for adults aged 65 and older.
Although randomized studies directly comparing these three vaccines to each other are lacking, the CDC points to evidence suggesting that each of these vaccines is more effective for individuals over 65 in preventing flu cases and reducing hospitalizations compared to the standard vaccine.
Flu complications tend to be particularly severe in older adults, with those aged 65 and over representing more than half of hospitalizations and over 70% of flu-related deaths, as highlighted in a 2013 study. This makes flu vaccinations especially crucial for this age group.
