These days, the moment you develop a little cough or start feel slightly sick, your brain might go immediately to COVID-19.
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But COVID-19, the disease caused by the coronavirus, has symptoms that are similar to other common viral infections, including the flu. So, if you don’t have immediate access to a flu or COVID-19 test, it can be hard to tell by your symptoms alone whether you might have it.
Though both COVID-19 and the flu can both make you feel lousy, they’re different illnesses caused by different viruses. Here’s a look at some of their key similarities and differences.
What they are + how they spread
The flu has been around for many years, and we’re aware of the two types of influenza viruses (A and B) that cause outbreaks during the winter months, says infectious disease specialist Kristin Englund, MD.
However, SARS-CoV-2, the coronavirus that causes COVID-19, is a new virus. “This is something none of us has ever seen before, so no one has any immunity against it,” Dr. Englund explains. “That’s why it’s been able to spread worldwide so rapidly — because no one is protected at this point.”
And while the first vaccine to protect against COVID-19 has been authorized for emergency use, not everyone can yet get vaccinated like with the flu.
Flu viruses and coronaviruses are passed from person to person in similar ways — through droplets that come out of someone’s nose and mouth when they cough, sneeze or talk. When another person inhales these droplets, that person can become infected. It might also be possible for someone to become infected by touching a surface that’s contaminated with the virus and then touching their mouth, nose or eyes.
Both kinds of viruses can be spread by someone who’s infected before they even develop symptoms. However, the CDC notes that COVID-19 is more contagious in certain populations than the flu.
“What we’re seeing with COVID-19 is these ‘super-spreading’ events where someone goes to a meeting or a party, and they have COVID-19 but don’t necessarily have symptoms, yet they are spreading the virus to many people around them at that time,” Dr. Englund says.
It’s possible to be infected with both viruses at the same time — but Dr. Englund says this is not common.
What are the symptoms?
According to the CDC, both COVID-19 and the flu can lead to a range of mild to severe illnesses. They both may cause:
- Shortness of breath.
- Sore throat.
- Runny or stuffy nose.
- Body aches.
Some people with COVID-19 also develop other symptoms. “We’re seeing more diarrheal illness, or nausea and vomiting, in patients with COVID-19,” Dr. Englund says. “Patients are also complaining of loss of sense of smell or taste, difficulty concentrating and confusion. COVID-19 seems to be impacting almost every organ system in the body.”
If you have these symptoms, the first thing to do is call your doctor’s office. They may direct you to the emergency room, their office or online for a virtual visit, or give you instructions for getting tested for the flu or COVID-19.
If you have severe symptoms, such as chest pain, shortness of breath, dizziness or a severe headache, go to the nearest emergency department or dial 911.
How long do the flu and COVID-19 last?
Typically, flu symptoms stick around for four or five days — maybe even up to seven days, Dr. Englund says, whereas COVID-19 may last 10 days or longer. It’s important to stay home if you feel sick so that you don’t risk spreading the flu or COVID-19 to others.
Most people with either illness are able to recover at home with rest, fluids and over-the-counter medicines for fever or body aches. But in some cases, they can both result in complications such as pneumonia, acute respiratory distress syndrome, and inflammation of the heart, brain or muscle tissue. These complications are more likely to affect older adults and people with underlying medical conditions.
There are also some additional complications associated with COVID-19, including blood clots and multisystem inflammatory syndrome in children. It’s important to monitor your symptoms and stay in touch with your doctor if you get sick.
Prevention is key for both
The best way to avoid getting or spreading COVID-19 or the flu is to practice healthy habits, including:
- Washing your hands frequently.
- Avoiding touching your eyes, nose and mouth.
- Avoiding close contact with people who are sick.
- Disinfecting frequently touched surfaces.
- Coughing and sneezing into your sleeve or a tissue instead of your hands.
- Staying home when you’re sick.
The CDC also recommends wearing a cloth face covering when with those who don’t live in the same household as you during the pandemic.
These simple steps can make a big difference in keeping you healthy and curbing the spread of COVID-19 and the flu.