For a long while, it was believed that we needed to bring fevers down in order to cure patients. Since fevers were always associated with illness, the thinking was if you conquer the fever, you defeat the illness. This thinking has changed in modern times.
What is a fever?
Fevers are a sign that your body is fighting an infection. Fevers are considered part of the innate immune system. This means that it is your body's first line of defense without specifically targeting a particular pathogen.
How Does Fever Fight Infections?
Fevers work to slow the progression of or kill certain dangerous pathogens. A fever may work well against some bacteria, fungi, or protists but not so well against others. Some parasites, for instance, have evolved to live in mammalian systems and may more easily survive feverish temperatures, whereas, a particular invasive bacterial species may not survive.
Viruses tend to remain intact and still possess the ability to infect during fevers. A fever can slow it down, but will not kill it. This is because a cell's replication machinery dysfunctions at higher temperatures and a virus needs those to propagate. The virus is still there though. The feverish temperatures that humans produce are not high enough to denature (disrupt) viral proteins and nucleic acids. If this were true, regular body cells would die too. SARS type Coronaviruses have been shown to survive temperatures up to 132 degrees Fahrenheit(1). So yes, that meme about using hot steam or blow dryers to kill the coronavirus in your nasal sinuses will not work.
Are Fevers Good Then?
Hospitals will and should only bring the fever down based on how you feel(2). If you feel nauseous, dizzy, are incoherent, or in pain, reducing the fever may help the patient be more comfortable but it is not required. Lying in a pool of sweat is not desirable by most patients so relief is usually sought. Generally, though, fevers are considered the first line of defense against pathogens and should remain that way so that the higher temperatures (between 100 and 103 degrees Fahrenheit) can boost the immune system and slow the progression of the invading pathogens(3). The increased temperature gives your immune system a chance to gather its defenses while the virus is held at bay. Fevers should really be used as a gauge to understand that one's body is fighting an infection(4). The body, however, can and does lose these battles occasionally so modern medicine should be there to help support the patient to more successfully combat the pathogen through antivirals, adequate fluids, respirators (if needed), and nutrition.
Can Fevers Impact the Brain?
Temperatures between 100.5 and 104 degrees Fahrenheit are considered low-grade to moderate fevers and thus would not cause any damage to brain and body tissues. Temperatures higher than 105 Fahrenheit are usually considered dangerous but this is rare. High fevers, in excess of 107.6 degrees, have been associated with seizures, memory loss, stroke and other forms of brain damage; so, to be safe, do not excessively wrap up yourself or your child in blankets with heating pads to "sweat out" the virus. Body temperature should be constantly monitored.
When should I call a medical professional?
Generally, if an average adult has a fever above 103 degrees, or a child higher than 104, a licensed medical professional should be called as this may be a sign of a serious infection.
Most Relevant References