Do You Need a High-Dose Flu Shot?


gray haired woman having her arm swabbed before a flu shot

Photo: Image Point Fr (Shutterstock)

The flu vaccine is more important than ever this year, so if you’re encountering the different versions for the first time, some of them may be confusing. Yes, there is a high-dose flu vaccine, and it’s one of the versions recommended for people over 65.

What does ‘high dose’ mean?

The way a vaccine works is to expose your immune system to a little bit of antigen. The antigen is something that the immune system can recognize and later respond to; in many flu vaccines, the antigen is an influenza virus that has been killed and ripped into pieces. (That’s why the flu shot cannot give you the flu.)

As we age, our immune system sometimes doesn’t respond as strongly as it did when we were younger, so a regular flu vaccine may not spur as strong an immune response as we need for the vaccine to be effective. One way around this is to just give more antigen. That’s the idea behind the high-dose shot: it just contains more of those virus pieces. Specifically, four times more.

Side effects are slightly more common with the high-dose flu vaccine than with the regular kind, but they’re the same types of side effects anyone might get from a flu shot, and like the regular flu shot they are not usually serious. The CDC says: “The most common adverse events experienced during clinical studies were mild and temporary, and included pain, redness at the injection site, headache, muscle aches, and malaise.”

If I’m over 65, do I need a high-dose flu shot?

The CDC says that any flu shot is fine if it’s been approved for people in your age group. But there are two flu vaccines that are specifically for adults who are 65 and older.

The high-dose shot is one, and the other is an adjuvanted vaccine. Instead of a higher dose of the antigen, it contains an adjuvant, which is an ingredient that makes your immune system react more strongly. (The adjuvant in this case is squalene oil.)

There haven’t been randomized studies comparing these two vaccines to each other, the CDC says, but there is evidence showing that each vaccine works better for people over 65 (preventing cases of the flu, and reducing hospital admissions) than the standard vaccine.

Complications of the flu are especially likely to be serious in older people, with those over 65 accounting for more than half of hospitalizations and more than 70% of deaths according to a 2013 study. So flu shots are especially important in this age range.



Source link