COVID-19 and Fever

Fever is one of the most common symptoms of COVID-19. But people with COVID-19 sometimes only have a low-grade fever or no fever at all.

What is considered a fever?

In general, a normal body temperature is around 98.6°F (37°C). A fever is a temperature above 100.4°F (38°C).

Because your normal body temperature may be a bit different, it is a good idea to get a baseline for what is normal for you. Find your normal body temperature by taking your temperature when you feel well. Check your temperature on a couple of different days in the morning and the afternoon. Your normal temperature will be somewhere in the middle of those readings.

Always talk to your health care provider for specific advice and instructions.

Read more about Fever and Taking Your Temperature.

Checking for fever is important in COVID-19

Many people with COVID-19 have a fever at some point during their illness.

Common symptoms of COVID-19 include fever, cough, and problems breathing. Other possible symptoms include headache, body aches, chills, fatigue, and loss of the sense of smell or taste. Some people may also have runny nose, sore throat, nausea, or diarrhea.

The most common cause of fever is an infection caused by bacteria or viruses. It is a good idea to check your temperature any time you have symptoms of fever. Symptoms can include chills, body aches, and feeling warm or flushed. If you think you might be sick, use a thermometer to check your temperature. Write down your temperature so you can tell your doctor.

If you have been exposed to someone with COVID-19, check your temperature once or twice a day in the days after exposure. Be sure to check your temperature before going to school or work. Screening for fever can help stop the spread of COVID-19.

COVID-19 symptoms, including fever, vary from person to person. Fever can be one of the first signs of COVID-19, or fever can appear later during the illness. It can be constant, or it can come and go for a few days or even weeks. That is why it is important to be fever free for at least 24 hours before stopping isolation.

COVID-19 without a fever

Although a fever is a common symptom of COVID-19, people may be infected with the coronavirus but not have fever.

According to available data, less than half of people who tested positive for COVID-19 reported fever as a symptom. Some people may have a low-grade fever at first and then get worse over time. In others, fever may come and go.

It is also important to remember that children tend to have milder COVID-19 symptoms, including fever. The symptoms usually do not last as long as they do in adults. But this does not mean that children don’t spread the virus or that they can’t get very sick from it.

It is possible to spread COVID-19 even if you do not have a fever or other symptoms. A lab test can show if you have the virus that causes COVID-19. 

Find information from the CDC about testing for COVID-19.

How often to take a temperature to check for COVID-19

How often you should take your temperature may depend on your job, health, and risk factors. If you are at risk for COVID-19 because of possible exposure to the virus, it is a good idea to check your temperature once or twice a day.

Checking temperature regularly is especially important for a caregiver or worker who has close contact with high-risk people such as the elderly or those who have chronic medical conditions.

Screening for fever and other symptoms can help detect COVID-19 early and prevent you from spreading the virus to others.

The best way to take a temperature

You can use a digital thermometer to take your temperature. An oral (by mouth) temperature is generally the best way to check for fever in adults and children over 4 years old.

Be sure that you wait at least 30 minutes after eating or drinking. Also, for the best measure of fever, do not take a fever-reducing medicine such as acetaminophen (Tylenol®) or ibuprofen within 4 hours of checking your temperature.

How to clean the thermometer

• Always follow manufacturer instructions for cleaning and use.
• Clean your thermometer before and after each use.
• Most digital thermometers can be cleaned using soap and water.
• You can also use rubbing alcohol (70% isopropyl alcohol) to wipe off the surface. Then rinse off with water.
• After cleaning, wipe dry with a clean cloth or allow it to air dry on a clean surface.
• Do not boil or soak the thermometer in water. Do not clean thermometers in the dishwasher.
• Wash your hands or use alcohol-based hand sanitizer before and after handling the thermometer.

All family members can use the same thermometer if it is cleaned properly after each use. Be sure to clean your hands and disinfect surfaces to avoid spreading germs.

Questions to ask your care provider about COVID-19 and fever

• How often should I check my child’s temperature?
• When my child has a fever, when should I take them to the doctor?
• Can my child have COVID-19 without having a fever?
• What symptoms should I be most concerned about?
• When is it safe to return to school or other activities?

Find more information on fever and COVID-19