English version updated 30 September 2021 - COVID-19 and influenza (flu) are both infectious respiratory diseases, and they share some similar symptoms. However, they are caused by different viruses, and there are some differences in who is most vulnerable to severe disease. There are also differences in how the diseases are treated. It is important to know the difference between COVID-19 and influenza to better protect yourself. This Q&A will help you know the facts about COVID-19 and influenza and make informed decisions about your health.
How are COVID-19 and influenza viruses similar?
COVID-19 and influenza are both respiratory diseases.
Both viruses share similar symptoms, including cough, runny nose, sore throat, fever, headache and fatigue. People may have varying levels of illness with both COVID-19 and influenza. Some may have no symptoms, mild symptoms or severe disease. Both influenza and COVID-19 can be fatal.
COVID-19 and influenza spread in similar ways.
Both COVID-19 and influenza are spread by droplets and aerosols when an infected person coughs, sneezes, speaks, sings or breathes. The droplets and aerosols can land in the eyes, nose or mouth of people who are nearby -- typically within 1 metre of the infected person, but sometimes even further away. People can also get infected with both COVID-19 and influenza by touching contaminated surfaces, then touching their eyes, nose or mouth without cleaning their hands.
Some of the same groups have a higher risk for severe illness from COVID-19 and influenza.
While all age groups can be infected with both the COVID-19 virus and influenza virus, these people are at higher risk for severe disease and death from both COVID-19 and influenza:
- older adults;
- people of any age with chronic medical conditions (such as chronic cardiac, pulmonary, renal, metabolic, neurologic, liver or hematologic diseases); and
- people with immunosuppressive conditions (such as HIV/AIDS, patients receiving chemotherapy or steroids, or malignancy)
Healthcare workers are at high risk of getting infected by COVID-19 and at high risk of getting infected by influenza.
Pregnant people and those who have recently given birth are at high risk for experiencing severe influenza and severe COVID-19.
The same protective measures are effective against COVID-19 and influenza.
To protect against COVID-19 and influenza, follow these public health and social measures:
- Maintain at least a 1-metre distance from others and wear a well-fitted mask when that’s not possible;
- Avoid crowded and poorly ventilated places and settings;
- Open windows or doors to keep rooms well ventilated;
- Cough or sneeze into a bent elbow or tissue and throw the tissue into a closed bin;
- Clean your hands frequently
- Avoid touching your eyes, nose and mouth;
- Stay home if you don’t feel well; and
- Contact your medical provider if you have any of the following severe severe symptoms of COVID-19, including:
- Shortness of breath,
- Loss of appetite,
- Confusion,
- Persistent pain or pressure in the chest,
- High temperature (above 38 °C)
Vaccination is an important part of preventing severe disease and death for both COVID-19 and influenza. Follow the advice of your local authorities on getting the influenza and COVID-19 vaccines. WHO recommends the influenza vaccine for older individuals, young children, pregnant people, people with underlying health conditions, and health workers.
COVID-19 vaccines are safe for most people 18 years and older, including those with pre-existing conditions of any kind, including auto-immune disorders. These conditions include: hypertension, diabetes, asthma, pulmonary, liver and kidney disease, as well as chronic infections that are stable and controlled.
If supplies are limited in your area, discuss your situation with your care provider if you:
- Have a compromised immune system
- Are pregnant or nursing your baby
- Have a history of severe allergies, particularly to a vaccine (or any of the ingredients in the vaccine)
- Are severely frail
People with mild symptoms of both COVID-19 and influenza can usually be cared for safely at home. For more information about caring for someone safely at home with COVID-19, watch this episode of Science in 5.
There are safe and effective vaccines for both COVID-19 and influenza.
COVID-19 vaccines have been proven to protect against severe illness and death caused by COVID-19 disease. Millions of people around the world have safely received COVID-19 vaccines, and the vaccines have met rigorous standards for safety, effectiveness and quality. Getting vaccinated may also protect the people around you. If you are protected from getting COVID-19, you are less likely to infect someone else. COVID-19 vaccines do not protect against influenza.
WHO recommends vaccinations each year to prevent severe influenza disease in high-risk groups: pregnant people, individuals with underlying health conditions, older adults, health workers, and young children.
How are COVID-19 and influenza viruses different?
Treatments for COVID-19 and influenza are different.
The treatment options in use for COVID-19 at medical facilities include oxygen, corticosteroids, and IL6 receptor blockers for severely ill patients. Treatment for people with severe respiratory illness includes advanced respiratory support such as the use of ventilators. Several other treatment options for COVID-19 are currently in clinical trials.
Antiviral drugs for influenza can reduce severe complications and death, and they are especially important for high-risk groups. It’s important to remember that antibiotics are not effective against influenza or COVID-19 viruses.
People with mild symptoms of both diseases can usually be treated safely at home. Click here for more information about caring for someone with COVID-19 safely at home.
Vaccines for COVID-19 and flu are different.
Vaccines developed for COVID-19 do not protect against influenza, and similarly, the flu vaccine does not protect against COVID-19. Follow the advice of your local authorities on getting the influenza and COVID-19 vaccines.
If I have had my flu shot, do I also need the COVID-19 vaccine?
Yes. You need both vaccinations.
Can someone be infected with COVID-19 and influenza at the same time?
Yes, it is possible to catch both diseases at the same time. The most effective way to prevent hospitalization and severe COVID-19 and influenza is vaccination with both vaccines.
Continue to follow prevention measures, such as maintaining at least a 1-metre distance from others, wearing a well-fitted mask when keeping your distance is not possible, avoiding crowded and poorly ventilated places and settings, opening windows and doors to keep rooms well ventilated and cleaning your hands frequently.
How can I protect myself against COVID-19 and influenza?
The most effective way to protect yourself from both influenza and severe COVID is to get vaccinated with both influenza and COVID vaccines.
The most effective way to prevent infection with the virus that causes COVID-19 is to get vaccinated and follow prevention measures: maintaining at least a 1-metre distance from others, wearing a well-fitted mask when keeping your distance is not possible, avoiding crowded and poorly ventilated places and settings, opening windows and doors to keep rooms well ventilated and cleaning your hands frequently.
Follow the advice of your local authorities on getting the influenza and COVID-19 vaccines.
