A sinus infection often causes a high fever, but it’s not always the case. There are many other potential symptoms of a sinus infection, including headache, congestion, tenderness around the eyes and cheeks, bad breath, and pain when chewing or swallowing.
A fever is your body’s natural response to inflammation as your immune system detects and attacks invading germs. Most people with a sinus infection experience this reaction in the form of a high temperature. It’s not clear why some people with sinus infections have higher fevers than others, but there are some theories.
Theories for why sinus infections cause fever
Most people with a sinus infection will have a high temperature, but some people with the same infection won’t. So why do some people have a fever when others don’t?
We don’t know for sure, but there are a few theories. One theory is that people with bacterial sinus infections have higher fevers because their immune systems are working harder to fight off the invading bacteria. This means that the immune system has less energy to keep your body temperature at its normal level.
Your body temperature might go up as a way for your body to defend itself better against the bacteria. Another theory suggests that people with bacterial sinus infections have higher fevers because their bodies are releasing more proteins called cytokines in response to the bacterial infection. These proteins can increase body temperature.
Frequent salty sneezes and sweat
When you have a sinus infection, your mucus is full of salt. If you have a lot of it, you might even taste it when you blow your nose. All that salt makes it harder to cool your body when you are hot. So, if you have a sinus infection, you might sweat more easily when you are hot.
When you sweat, you cool your body by taking water from inside your body and moving it to the surface of your skin. But salty sweat doesn’t evaporate as quickly as plain water. So, salty sweat doesn’t cool you off as well as plain water would.
Viral infection may boost the temperature
People with a viral sinus infection can also have a high fever. One theory is that the immune system of someone with a viral infection reacts by releasing extra cytokines.
Like in a bacterial infection, these proteins can increase body temperature. Other theories are that the viral infection has made your body more sensitive to temperature changes, or that a viral infection disrupts the way your body controls its temperature.
Bacterial growth may increase the temperature
Another theory is that bacterial growth in a sinus infection raises body temperature. This could happen because bacteria produce a gas called hydrogen sulfide. This gas can warm your body. Another possibility is that bacteria release more proteins called cytokines in response to the bacterial infection. Like in a viral infection, these proteins can also increase body temperature.
Nasal mucus and fever
Some sinus infections cause a high temperature without any infection. This happens when your sinuses swell and push on nearby nerves. When these nerves get pressed, they send an abnormal signal to your brain. Your brain thinks there has been damage to the surrounding tissues.
So, it sends the signal for inflammation and triggers a fever. However, this type of fever is not as high as one caused by an infection. In general, a sinus infection can cause a temperature of up to about 39 degrees C (102 degrees F). A non-infectious sinusitis fever, on the other hand, can cause a temperature of up to 37 degrees C (98 degrees F).
A sinus infection often causes a high fever, but it’s not always the case. There are many other potential symptoms of a sinus infection, including headache, congestion, tenderness around the eyes and cheeks, bad breath and pain when chewing or swallowing.
There are many theories for why sinus infections cause fever, including frequent salty sneezes, viral infection, bacterial growth, and nasal mucus. A high temperature is not always a sign of a sinus infection, but it is a good indication that the immune system is working hard to fight the infection.