Something this Fool feels strongly about:

I recently got a flu shot, and I encourage you to do the same. The seasonal flu kills between 3,000 to 49,000 Americans every year, so by getting a flu shot you're helping to prevent thousands of unnecessary deaths. 

But there's another benefit. By getting a flu shot, you're also aiding future vaccine research. Developing new vaccines is extremely expensive and, unlike blockbuster drugs like Pfizer's (NYSE: PFE) Viagra or Lipitor, there is no recurring income for the maker; you get the vaccine once and then you're "cured for life." Therefore, vaccine development depends on widespread adoption to make continued research worthwhile for pharmaceutical company shareholders.

This is important, as the very same companies producing and distributing this year's flu shot -- Sanofi (NYSE: SFY), Merck (NYSE: MRK), Novartis (NYSE: NVS), GlaxoSmithKline (NYSE: GSK), AstraZeneca (NYSE: AZN) -- are all companies that have worked to develop a vaccine for AIDS, the fatal disease that kills 2 million people each year. Their shareholders will not let them continue such expensive, often discouraging, research if they think there isn't a large market for vaccines. By getting a flu shot, you show there still is.

That may seem obvious, but unfortunately vaccines have come under attack by conspiracy theorists and celebrities with influential soapboxes. Many parents are withholding routine vaccinations (for measles, polio, etc.) from their children out of well-meaning but misguided fear.

These parents would do well to listen to Roald Dahl, author of beloved children's books like Charlie and the Chocolate Factory and James and the Giant Peach. Dahl's daughter Olivia died of measles at the age of 7, and Dahl spent the rest of his life strongly urging parents to vaccinate their children. As Dahl wrote, "I know how happy [Olivia] would be if only she could know that her death had helped to save a good deal of illness and death among other children." Yet, many parents still don't listen.

The tragedy is that, like comic book superheroes, vaccines seem totally unnecessary when they actually do their job. None of us, unlike Dahl, has ever seen a child die of polio or measles, but that's only because vaccination is ubiquitous.

We never did learn to cure these diseases, so without widespread vaccination they could start killing kids again. 

So please, listen to your doctor and vaccinate, vaccinate, vaccinate.