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There are many reasons to get an influenza (flu) vaccine each year. Because of the on-going COVID-19 pandemic, getting a flu vaccine during 2020-2021 is be more important than ever. Flu vaccines will not prevent COVID-19, but they will reduce the burden of flu illnesses, hospitalizations and deaths on the health care system and conserve scarce medical resources for the care of people with COVID-19.  Additionally, at least one study shows that there may be another benefit to getting the flu vaccine — to fight the severity of COVID-19.

In a recent study conducted by Dr. Ming-Jim Yang, a third-year resident in family medicine in the department of community health and family medicine at the University of Florida in Gainesville, it was discovered that the flu vaccine may lesson the severity of COVID-19 in cases.  The study showed that patient who has NOT received the flu vaccine “were 2.4 times greater odds of being hospitalized and 3.3 times greater chance of being admitted to an ICU.”    Dr. Yang is careful to point out that  “The flu and COVID-19 are indeed different disease processes caused by different viruses, although some of the symptoms may overlap between the two diseases, they potentially have different short-term and long-term consequences. COVID-19 has a much higher mortality rate than the flu and the flu doesn’t have the same long-term lung, heart and brain issues being seen with those affected with COVID-19.”

Furthermore, they do not know why the flu vaccine would have a beneficial side effect on COVID-19 patients.   They believe that the flu vaccine stimulates the patient’s immune system to step up and fight off COVID-19 more quickly and rigorously.   To read a summary of Dr. Yang’s findings, read this article by Alan Mozes, HealthDay Reporter that was recently published on WebMD.

While many symptoms of the Flu and COVID-19 overlap, there are some specific symptoms that may indicate COVID and they should be taken seriously.

Symptoms of COVID-19

The symptoms of COVID-19 range from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus. People with these symptoms may have COVID-19 and should be tested:

  • Fever or chills
  • Cough
  • Shortness of breath or difficulty breathing
  • Fatigue
  • Muscle or body aches
  • Headache
  • New loss of taste or smell
  • Sore throat
  • Congestion or runny nose
  • Nausea or vomiting
  • Diarrhea

This symptom list does not include all possible symptoms. You can find the latest updates from the CDC here.


From the Center for Disease Control (CDC)

What is the difference between Influenza (Flu) and COVID-19?

Influenza (Flu) and COVID-19 are both contagious respiratory illnesses, but they are caused by different viruses. COVID-19 is caused by infection with a new coronavirus (called SARS-CoV-2) and flu is caused by infection with influenza viruses.

There are some key differences between flu and COVID-19. COVID-19 seems to spread more easily than flu and causes more serious illnesses in some people. It can also take longer before people show symptoms and people can be contagious for longer. Another important difference is there is a vaccine to protect against flu. There is currently a limited supply of COVID-19 vaccine in the United States, but supply will increase in the weeks and months to come. The best way to prevent infection is to avoid being exposed to the virus. More information about differences between flu and COVID-19 is available in the different sections below.

Because some of the symptoms of flu and COVID-19 are similar, it may be hard to tell the difference between them based on symptoms alone, and testing may be needed to help confirm a diagnosis. Flu and COVID-19 share many characteristics, but there are some key differences between the two.

While more is learned every day, there is still a lot that is unknown about COVID-19 and the virus that causes it. This page compares COVID-19 and flu, given the best available information to date.

Is there a test that can detect both flu and COVID-19?

Yes. CDC has developed a test that will check for A and B type seasonal flu viruses and SARS CoV-2, the virus that causes COVID-19. This test will be used by U.S. public health laboratories. Testing for these viruses at the same time will give public health officials important information about how flu and COVID-19 are spreading and what prevention steps should be taken. The test will also help public health laboratories save time and testing materials, and to possibly return test results faster.

The Food and Drug Administration (FDA) has given CDC an Emergency Use Authorization  for this new test. Initial test kits were sent to public health laboratories in early August 2020. CDC will continue to manufacture and distribute these kits.