Is It Possible to Have the Flu and COVID-19 At the Same Time?

It's technically possible to be infected with both the influenza virus and the coronavirus that causes COVID-19, but it is extremely rare.

The flu (influenza) is a respiratory illness caused by influenza viruses. 

COVID-19 is a novel (new) coronavirus, not previously identified in humans, that is responsible for an outbreak of respiratory illness that became a global pandemic in 2020. COVID-19 is different from other coronaviruses that cause mild illness, such as the common cold.

Symptoms of the influenza (the flu) and COVID-19 that are similar include:

• Fever or chills
• Cough 
• Fatigue
• Headache
• Muscle or body aches
• Sore throat
• Runny nose
• Stuffy nose/congestion
• Diarrhea

Additional symptoms of COVID-19 may also include:

• Shortness of breath
• Difficulty breathing
• Bluish lips or face
• Persistent pain or pressure in the chest
• New confusion or inability to arouse
• Altered sense of taste and/or smell
• Nausea
• Feeling unwell (malaise)
• Loss of appetite

Both influenza (the flu) and COVID-19 are caused by viruses transmitted from person-to-person through respiratory droplets propelled into the air when an infected person sneezes or coughs. Less commonly, people may catch the flu or COVID-19 by touching a surface or object that has the virus on it, and then touching their mouth, nose, or eyes.

It is technically possible to have both influenza (the flu) and COVID-19 at the same time, because they are different viruses, however, it is extremely uncommon. There have only been a small number of known cases of patients having both illnesses at the same time.

In the early days of the COVID-19 pandemic when testing for the coronavirus was not readily available, doctors often tested patients for the flu first. If flu tests came back positive, patients usually were not tested for COVID-19. And once COVID-19 became more widespread in the U.S., flu season was coming to an end. It is possible that there were cases of people who had the flu and COVID-19 that were not diagnosed with both.

Influenza (the flu) is usually diagnosed with rapid influenza diagnostic tests (RIDTs) that can provide results in about 15 minutes. These are less accurate than other flu tests called rapid molecular assays that detect genetic material of the virus and provide results in about 15-20 minutes. Other specialized flu tests may be used in hospitals or state public health laboratories. These specialized tests use a long swab to swipe the inside of the nose or the back of the throat, which is then sent to a lab for testing. Results may take several hours.

If COVID-19 is suspected, a viral test in which a long swab is used to take a sample from the nose or throat is used, which is then sent to a lab for testing to diagnose the illness. Some tests are rapid and results area available within a few hours. Other tests may take several days to receive results. 

Another test that can determine if a person had a past COVID-19 infection is an antibody test. This test is not helpful in diagnosing current infections because it can take up to 3 weeks following infection for the body to produce antibodies to the virus. When a person has antibodies to COVID-19 they may have some protection against re-infection, however, researchers do not yet know how much protection antibodies provide or for how long any protections might last. 

The main way to prevent influenza (the flu) is to get vaccinated every year. 

To protect yourself from getting COVID-19: 

• Wash hands frequently with soap and water for at least 20 seconds. 
• If soap and water are not available, use hand sanitizer with at least 60% alcohol and use a sufficient amount to rub in for 20 seconds.
• Do not touch your mouth, nose, or eyes with unwashed hands.
• Avoid close contact with anyone who has been diagnosed with COVID-19. 
• If there is an outbreak in your community, stay at home and limit close contact with others. 
• Maintain a distance of at least 6 feet from other people. 
• Wear a face mask when out in public.