Doctors have been reminding us to get our flu shots since the 1930s, but every winter people inevitably go back and forth about whether they should actually do it. For some people, the decision has been harder to make in recent years, as rumors of the vaccine’s inefficacy and potential to cause mild illness — together with the rise of the anti-vaccine movement — have reached more and more people. But this year, new CDC estimates showed that the flu also kills a lot more people than scientists once thought.
The truth is that the flu vaccine, which is created in a slightly different form every year, is not guaranteed to be effective. If you’re a healthy adult, there’s a high chance you might not even need it, seeing as influenza is really only life threatening to people who are really old, really young, pregnant, or immunocompromised. Furthermore, there’s no denying that there are some small costs to getting one, which include the chance you might come down with mild flu symptoms, experience some muscle soreness, exacerbate a long-standing fear of needles, and perhaps have to pay a small financial fee.
Still, the risk you take by avoiding the flu shot far outweighs any of the costs.
The costs to you are obvious: When you avoid getting vaccinated, you risk your body being totally unprepared for whatever strain of flu virus World Health Organization researchers predict will strike in the coming year. While there’s no guarantee that they’ll get it exactly right — there are so many strains in the world to choose from — that vaccine can still confer some protection against other strains of influenza, not only slightly reducing your symptoms but also decreasing the amount of virus that you carry and transmit.
Which leads us to the greater cost of not getting a flu shot: the fact that it puts so many other people in danger.
In general, viruses spread by finding a host, incubating and multiplying inside that host, then bursting outward from that host — through sneezes, snot, and spit — into the mucus membranes of other potential hosts, kicking off the cycle all over again. The point of a vaccine is to train the immune system to kill flu virus particles ahead of time, so that when a person does encounter the flu virus, the body can kill it before it has the chance to spread.
When you don’t get vaccinated, you give the flu a free pass to use you as a breeding ground, putting other people — the babies, old people, moms-to-be, and the sick we mentioned before — at risk of becoming gravely ill. In contrast, when enough people get vaccinated, they produce what’s known as “herd immunity” — a form of population-wide protection against an infectious disease caused by the inability of the virus to find any hosts in which they can settle.
Doctors can’t guarantee that you’ll ever feel the individual benefits of getting a flu shot, and, unless you’re an epidemiologist, you probably won’t ever see the benefits it confers to the entire population. What you may see, however, is the effect that skipping a flu shot has on other people, especially those compromised, aforementioned few that will need much more than just a few days off work and a handful of Sudafed to recover.