Do you know these similarities and differences between flu and COVID-19?

Bothe influenza (flu) and Coronavirus are contagious respiratory illnesses. Both are caused by different viruses. Flu is caused by the influenza virus whereas COVID-19 is caused by a new Coronavirus also known as SARS-CoV-2.

Similarities and Differences between Flu and COVID-19

Both coronavirus and flu have some major differences between flu and COVID-19. Coronavirus can spread more easily than the flu and causes more serious illnesses in some people. It takes longer to show symptoms in people and can be contagious for a longer period.

Another main difference is that vaccines are accessible to protect against the flu. For, COVID-19, there is no vaccine available to prevent Coronavirus. The only way to prevent infection is to avoid being exposed to the virus. Some of the symptoms of flu and COVID-19 have similarities.

It is difficult to tell the difference between them based on symptoms alone. Testing is required to help confirm a diagnosis. Influenza and COVID-19 have many characteristics, but there are some dissimilarities between the two. Read further to uncover more similarities and differences between flu and COVID-19.


Coronavirus vs Flu

Symptoms of Flu and coronavirus

Covid-10 and flu can have different signs and symptoms, from no symptoms (asymptomatic) to severe symptoms. Here are the common symptoms that both can share:

  • Cough
  • Fever or feeling feverish/chills
  • Difficulty breathing or shortness of breath
  • Fatigue or tiredness
  • Body aches or muscle pain
  • Sore throat
  • Headache
  • Runny or stuffy nose
  • Some people may have diarrhea and vomiting, it is more common in children than adults.

For both viruses, it is possible to spread the virus for at least 1 day before experiencing any symptoms.

Both COVID-19 and influenza virus can spread from person-to-person, are transmitted by contact, fomites, and droplets. 

Both viruses can result in serious illness and complications. Particularly for

  • Older adults
  • Pregnant women
  • People who have other medical conditions

Both COVID-19 and flu can cause complications, such as:

  • Respiratory failure
  • Acute respiratory distress syndrome (i.e. fluid in lungs)
  • Pneumonia
  • organ failures including respiratory failure, kidney failure, and shock
  • chronic medical conditions that include the lungs, nervous system, heart, or diabetes
  • Inflammation of the heart, brain, or muscle tissues
  • Heart attacks and stroke
  • Sepsis

Differences between COVID-19 and Flu Influenza

Flu Influenza


The flu virus can affect mild to a serious illness that includes common signs and symptoms which are listed above. Coronavirus can cause more severe illness in some people. There are some signs and symptoms of COVID-19 that are different from the flu. The difference may include a change in the loss of taste or smell.
Characteristically, a person can develop symptoms anywhere from 1 – 4 days after infection. A person can develop symptoms 5 days after being infected. But the time range can vary.
People with the flu are transmittable for at least 1 day before they show symptoms. How long people can spread the virus that causes COVID-19 is still under investigation.
The flu virus spreads in a similar way as COVID-19. It is possible for people to spread it for about 2 days before they experience symptoms.
Children are more vulnerable to the flu virus. But Coronavirus is more infectious among certain populations and age groups than flu.
People who are infected with the flu will recover in a few days or less than 2 weeks. Some people may have medical complications that are listed above School going children infected with COVID-19 are susceptible and can have Multisystem Inflammatory Syndrome in Children (MIS-C), which is an uncommon but serious complication of COVID-19. People with COVID-19 can face the complications of blood clots in the veins and arteries of the lungs, legs, heart, or brain.
Prescription influenza antiviral drugs are approved by the FDA to treat flu. The National Institutes of Health (NIH) has created guidance on the treatment of the COVID-19 external icon, which will be updated daily.

These are the similarities and differences between flu and COVID-19. Take the necessary precautions to protect yourself from these diseases and others around you by learning the facts.