Studies on fish suggest that delaying the use of medication may be beneficial for humans.
According to new research from the University of Alberta, it may be better to allow a mild fever to run its natural course rather than immediately resorting to medication.
The researchers discovered that allowing a moderate fever to go untreated in fish helped them quickly eliminate the infection from their bodies, regulate inflammation, and repair any damaged tissue. “We let nature do what nature does, and in this case, it was very much a positive thing,” says immunologist Daniel Barreda, lead author on the study and a joint professor in the Faculty of Agricultural, Life & Environmental Sciences and the Faculty of Science.
Moderate fever is self-resolving, meaning that the body can both induce it and shut it down naturally without medication, Barreda explains. The health advantages of natural fever to humans still have to be confirmed through research, but the researchers say because the mechanisms driving and sustaining fever are shared among animals, it is reasonable to expect similar benefits are going to happen in humans.
That suggests we should resist reaching for over-the-counter fever medications, also known as non-steroidal anti-inflammatory drugs, at the first signs of a mild temperature, he says. “They take away the discomfort felt with fever, but you’re also likely giving away some of the benefits of this natural response.”
The study helps shed light on the mechanisms that contribute to the benefits of moderate fever, which Barreda notes has been evolutionarily conserved across the animal kingdom for 550 million years. “Every animal examined has this biological response to infection.”
For the study, fish were given a bacterial infection and their behavior was then tracked and evaluated using machine learning. Outward symptoms were similar to those seen in humans with fever, including immobility, fatigue, and malaise. These were then matched to important immune mechanisms inside the animals.
The research showed that natural fever offers an integrative response that not only activates defenses against infection, but also helps control it. The researchers found that fever helped to clear the fish of infection in about seven days — half the time it took for those animals not allowed to exert fever. Fever also helped to shut down inflammation and repair injured tissue.
“Our goal is to determine how to best take advantage of our medical advances while continuing to harness the benefits from natural mechanisms of immunity,” says Barreda.
Reference: “Fever integrates antimicrobial defences, inflammation control, and tissue repair in a cold-blooded vertebrate” by Farah Haddad, Amro M Soliman, Michael E Wong, Emilie H Albers, Shawna L Semple, Débora Torrealba, Ryan D Heimroth, Asif Nashiry, Keith B Tierney and Daniel R Barreda, 14 March 2023, eLife.