Doctors used to call
So what do you do? Because fever-reducing medicines make you feel better, the natural thing is to reach for that bottle of
A recent study published in the Proceedings of the Royal Society by researchers at McMaster University found that reducing your fever is likely to extend your illness. Moreover, fever-reducing medicines can increase the rate of transmission by making you feel well enough to go back to work or school and cough and spread your germs. The fact that you feel better doesn't mean that you are better, just that you've become a more likely
Paul Andrews, an evolutionary biologist at McMaster and one of the coauthors of the Royal Society article, puts it this way: "I think it's pretty darn clear that fever is an evolved adaptation. Fever activates, regulates and promotes the immune system."
In warm-blooded organisms such as birds and mammals, Andrews explains, "our brain kicks in to regulate our body temperature." Cold-blooded reptiles and fish have their own strategies: "Fish move into warmer water to raise core body temperature when they have an infection." So fever is what evolutionary biologists call evolutionarily conserved: It's there for a purpose, and during acute illnesses, it can be good for the host. High temperatures may kill some germs, but even more important, fever sets in motion an entire immunological process.
The idea that reducing fever with medication might make you sicker is not new. Studies of rhinovirus (a cause of
But acetaminophen is no answer. According to a 1989 study in the Journal of Pediatrics, children with chickenpox who took acetaminophen remained sick and infectious longer than those who didn't.
And what about taking that mixed cocktail of over-the-counter medication to stop the
And there's still another twist: Fever isn't always your friend. As Ewald argues, fevers and inflammation in chronic as opposed to acute infections might actually be harmful. If persistent infections keep causing inflammation and damaging cells, the harm done to the body could be significant. You want to cut down on persistent inflammation, which is why anti-inflammatory drugs are used in
Untangling these runic complications will take much more research. But what we can say unequivocally is that there's likely to be a real evolutionary benefit to staying at home while you're acutely sick. Andrews points out that taking fever reducers may push circulating influenza toward virulence by allowing nastier strains to spread. Ewald makes the same point in reverse: One way to push influenza strains toward mildness is to keep everyone sick enough to medicate at home instead. If you had a case of flu so mild you barely noticed it, you'd only spread mild germs. So, logically, if the really sick didn't go out, the influenza strains that managed to spread would likely evolve toward mildness. That's good for everyone.
The long and short of it: If you're sick enough to need medicine, do yourself and everyone else a favor. Just stay home.