Ask Doc We're no strangers to controversy...
Over the last five years, we've covered plenty of controversial topics... I've warned you about the dangers of statins and diet soda, and dispelled ridiculous myths about salt.
Whenever we write about one of these issues, it stirs up a lot of emotional responses in our inbox. And I knew when I wrote about why folks should get the flu shot this year, we'd be flooded with e-mails again.
But this time, I was shocked by the amount of misinformation lots of folks are reading.
So today, I want to cover the most-asked questions and dispel some misconceptions...
As always, keep sending us your questions, comments, and topic suggestions to [email protected]... We read every e-mail.
Q: You did not mention that getting a flu shot increases your susceptibility to COVID-19. – C.B.
A: That's because it doesn't.
Recently, a video went viral online that appeared to show TV personality Dr. Oz claiming that the flu vaccine increases your risk of COVID-19. But the video was out of context – and, in fact, Dr. Oz said that getting a flu shot wouldn't increase susceptibility to the coronavirus.
Similarly, a brand-new study in the Journal of Clinical and Translational Science found there is no connection between flu vaccination and COVID-19. What's more, I actually discussed an early finding from Italy that those most likely to die from COVID-19 were patients with coinfections... In other words, folks who had the flu at the same time as COVID-19 were more likely to die. That's just one more reason your flu shot is important this season. You can read my full take on coinfections right here.
Q: Hi Doc, very interesting thoughts. It has been suggested that the immunity of the flu vaccine diminishes over time – quite quickly. When do you suggest we should have the injection? And if we have it early, should we have a second one later, say in January? Grateful for your thoughts on this. – T.W.
A: This is a great question. A few studies have shown that the antibodies we create for the flu from the vaccine begin to diminish around six months. In addition, the flu is one of the most rapidly mutating viruses out there, so the virus you see at the beginning of flu season often looks nothing like the one hitting in February and March. That's also why you can get the flu twice in one season.
Most prescribers recommend getting the flu vaccine around the beginning of October. That means during the height of flu season – January – you'll be well-protected.
Q: When you discuss success rates for the flu vaccine, are you using relative percentages (which is typical and incorrect)? Or are you using absolute percentages, which is the correct way to express effectiveness? – M.M.
A: We discuss the vaccine efficiency rates as measured by medical studies. For instance, one of the statistics out there is this: Older folks who receive the vaccine have a 40% lower risk of hospitalization. This comes from a meta-analysis of 30 studies that looked at hospitalized patients. (I urge you to read the paper, here.)
Now, as the authors point out, the common approach for these studies does involve relative differences between patients in the hospital. In other words, they looked at those who had received the vaccine and those who hadn't. It's difficult to have controlled pools for these studies, but we did find an important one that calculated absolute risk.
Published in the Clinical Infectious Diseases journal, the paper looked only at the vaccine for the 2015 to2016 and 2016 to2017 seasons. It highlights that between the low-dose vaccine and high-dose vaccine, there was no statistical difference. The effectiveness against all influenza types was also not statistically important. However, one of the vaccines did in fact provide a 62% absolute protection for influenza B.
Breakdowns like this are important. Yes, some years the flu shot has little to no effectiveness. But it's also important to look at each strain within the vaccine.
Q: Wouldn't all of the COVID precautions (masks, distancing, etc. etc.) make it virtually impossible to become infected with the flu virus, which should make the vaccine more unnecessary than any past year? – S.R.
A: Yes, most of the precautions for COVID-19 are ones that also keep us safe from the flu. And most of the mask studies folks use today were originally looking at the spread of diseases like influenza.
I don't know where you live, but we've seen a bunch of folks flaunting local guidelines. No masks, no social distancing... heck, we've seen pictures from so many indoor weddings recently (all without a mask in sight), we're wondering just how seriously folks are taking either the flu or COVID-19.
We think getting the flu vaccine is a personal choice. That's why I only recommend it for those in higher-risk groups. We like it not just for the lowered risk of hospitalization for the flu itself, but also for the heart protection that it can provide. But do your research and make the best decision for your own health.
What We're Reading...
- Did you miss it? How to make it through this year's flu season safely.
- Something different: Disney is feeling the pain from COVID.
Here's to our health, wealth, and a great retirement,
Dr. David Eifrig and the Health & Wealth Bulletin Research Team
October 2, 2020