What counts as a fever, anyway? Get the facts on this key coronavirus symptom

It’s considered one of the chief symptoms of coronavirus, along with a dry cough and shortness of breath, but how much do you really know about fevers?

About 44 percent of coronavirus patients initially have a fever, but 80 percent eventually develop one, according to a study from China, Business Insider reports.

More than 2.7 million cases of the COVID-19 virus have been confirmed worldwide with more than 193,000 deaths as of April 24, according to Johns Hopkins University. The United States has more than 871,000 confirmed cases with more than 50,000 deaths.

The World Health Organization has declared the COVID-19 virus a global pandemic. In the United States, President Donald Trump has declared a national emergency.

Here’s what you need to know about fevers.

How do you know if you have a fever?

Some illnesses, including coronavirus, cause a rise in the body’s temperature, which may help you fight off infection, according to the Mayo Clinic.

If you have a thermometer handy, you’re ready to go. Use an oral thermometer for adults and children, and a rectal thermometer for infants. Here’s what the readings mean.

Normal body temperatures vary from person to person, and also change throughout the day as you eat, exercise, sleep and go about your business, Medical News Today reports. Your body temperature normally peaks around 6 p.m and reaches its lowest point about 3 a.m.

The average body temperature is considered to be around 98.6 degrees Fahrenheit, Harvard Medical School reports.

Recent studies, however, show average normal body temperatures may be falling, reports the Harvard Health Blog. The average may now be more like 97.5 degrees, perhaps because of lower metabolic rates or fewer infections to fight off.

When your temperature rises to 100.4 degrees or higher, you have a fever, Harvard Medical School reports. When it reaches 103 degrees or higher, you have severe fever.

What are the other signs of a fever?

Aside from a high temperature, fever symptoms can include feeling cold, shivering, lack of appetite, dehydration, depression, lethargy, trouble concentrating, sleepiness and sweating, Medical News Today reports.

Muscle aches and weakness also can be symptoms of fever, according to the Mayo Clinic.

A severe fever can cause irritability, confusion, delirium and seizures, Medical News Today reports.

How do you treat a fever?

Drink plenty of fluids to stave off dehydration and help your body fight the infection, says the Mayo Clinic. Also, eat light meals that are easy to digest.

You also should get plenty of rest, take warm baths and dress lightly unless you have chills, according to the clinic. Ibuprofen, naproxen, acetaminophen or aspirin also may help.

When should you seek medical help?

Call your doctor if you have a fever higher than 104 degrees Fahrenheit, suggests Harvard Medical School.

Unexplained fevers in infants and children can be more serious, according to the Mayo Clinic.

Call your doctor if an infant younger than 3 months has a 100.4-degree or higher temperature, an infant between 3 and 5 months has a 102-degree or higher temperature, and if an infant ages 6 to 24 months has a 102-degree temperature for more than a day, the clinic suggests.

Fevers in children over 2 years old are normally not a problem, but call your doctor if one lasts more than three days or if the child becomes listless, vomits or has a severe headache, advises the Mayo Clinic.

What are the other symptoms of coronavirus?

Coronavirus symptoms can show up in as few as two days after exposure or as many as 14 days, Business Insider reports. The most common symptoms include fever, dry cough and shortness of breath.

Some patients may have diarrhea, nausea, vomiting or abdominal discomfort a few days before developing respiratory symptoms, although it’s not common, according to the publication.

Other symptoms may include fatigue, sore throat, headache, joint or muscle pain, chills and a runny nose, Business Insider reports.

Most people with a mild case of COVID-19 feel better after a few days, but some develop severe breathing problems requiring hospitalization, according to the publication. Death can occur when fluid builds up in the lungs.

This story was originally published March 22, 2020 at 11:26 AM with the headline "What counts as a fever, anyway? Get the facts on this key coronavirus symptom."