I got my flu shot and my new COVID vax at the same time. Here’s why.

Infectious Diseases Vaccines

I got my new COVID vax and my flu shot at the same time because it was the easiest way for me to get both.

This week, I got my latest COVID vax and my flu shot at the same time because it was the easiest way for me to get both done at one time and in advance of a trip I have coming up–and there were very few downsides.

The first thing to know is that it is safe to get both your COVID vaccine and your flu vaccine together–in the same arm or different ones. I opted for one in each arm because (ever the scientist) I wanted to know which one would make my muscle more sore. Also, on the other occasion that I got the Moderna vaccine, I did get a mild itchy rash on that arm. So I wanted them to be on different sides in case that happened again.

Another important consideration: does it work as well? Yes, recent research shows that getting both shots at once provides equal protection versus getting them spaced out on different days.

Given that it’s safe and effective, I wanted to do whatever was the easiest. My local pharmacy will do multiple vaccines at the same appointment, so getting both together meant just one appointment. I wanted to get the COVID vaccine as soon as possible because wastewater sampling shows a MAJOR spike in cases in my area. And I have a big trip coming up so I wanted to get them both done with well before I have to get on a plane.

I also considered whether I might have a higher chance of side effects from getting both at once. My annual flu vaccine usually leaves me feeling pretty bad for a whole day, but I haven’t had a strong reaction to the COVID vaccine in the past. The same study of coadministered vaccines versus separate vaccines showed that about 1 in 6 people who got the flu shot had post-vaccine symptoms (like fever, headache, fatigue). 1 in 4 people who got the COVID vaccine alone had some post-vaccine symptoms. And about 1 in 4 who got both at once had some symptoms. This study indicates that I’m no more likely to have symptoms after getting the COVID vaccine or the COVID+flu vaccine, so the question I asked myself was: do I want to risk feeling like trash on one day or on two different days? The answer was one day.

Another possible downside I considered (and probably should have planned around) was whether I might feel extra bad after getting two shots at once. And in hindsight, that turned out to be a biggie. I did not find evidence either way on the severity of side effects after covaccination, just how often there were any side effects at all. Well, I felt pretty bad. Worse than typical for a flu shot, and definitely worse than my previous experience with COVID-19 shots. I should have done it on a Friday afternoon, which is what I normally plan for my annual flu shot. Then I can lay low on Saturday. Instead I had to work and it was kind of miserable.

One other argument for not getting both at once is the idea that we should hold off on flu vaccines until the seasonal virus really gets going. I personally think that this isn’t a great reason for most people to wait. The annual flu vaccine you get in September is exactly the same as the one you get later the same season. Also, I am 46. There’s evidence that flu vaccine protection wanes meaningfully before 6 months in older adults, but not so much in my age group. It’s already mid-September, so that means I’m most likely well-protected through mid-March. Flu season usually ends by then, so I’m not too worried about an exposure in April.

If you are worried about waning protection, know that the research on this does recommend against “early vaccination”–meaning July and August. September and October are optimal, even for older adults. At this point, waiting means trading in a few weeks of partial protection in late March for a few weeks of zero protection now.

So for me: on paper, two shots at once had more pros than cons. I did feel pretty terrible the next day, so next year I’ll either schedule it for a Friday or, I’ll get them at separate times. And for what it’s worth, the COVID shot made my arm more sore. Next year, I’ll do that one in my non-dominant arm.

Link to Substack Post