In flu season, it can be hard to tell if your symptoms are strep, flu, or COVID. These illnesses share many common symptoms, making it difficult to distinguish between them without proper testing. What are the differences and similarities between strep throat, the flu, and COVID-19?
Flu or COVID: How Can You Tell?
The flu and COVID-19 are respiratory viruses. The main difference is which virus causes them. Unlike COVID-19, which is caused by a coronavirus (SARS-CoV-2), the flu is caused by various strains of the influenza virus. Although the flu and COVID-19 are caused by different viruses, they share very similar symptoms and may require testing to be able to tell which one you might have. Difficulty breathing is more rare for the flu, which typically presents with flu symptoms such as fever, chills, body aches, fatigue, and sore throat.
Both flu and COVID-19 may be treated with antiviral drugs, which are most effective when administered early after symptom onset.
Similarities between Flu and COVID
The flu and COVID-19 share many characteristics and both can appear asymptomatic, which means you show no symptoms. Shared symptoms include:
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- Fatigue
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- Fever/chills
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- Body aches
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- Headache
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- Sore throat
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- Runny nose
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- Coughing
Differences Between Flu and COVID
While the flu and COVID-19 share a lot of the same symptoms, there are some signs you can use to tell the difference.
Symptoms of COVID-19 include shortness of breath and difficulty breathing. Having the flu can also cause these symptoms, but it is much more rare for difficulty breathing to be a flu symptom. COVID-19 is documented to cause a loss of taste and smell, unlike the flu. This symptom can appear with the flu, but is not likely.
Not sure if it’s COVID or the flu? Maybe it’s RSV? Rapid Testing LLC offers curbside testing at Advanced Urgent Care’s clinics – all without a provider visit. Get tested for COVID, RSV, and the flu in a single test, or just for COVID or the flu.
Perhaps the most drastic difference between the two is how suddenly symptoms can appear. While both can go days without showing symptoms, the onset of those symptoms vary greatly. Anyone who has had the flu will know just how quickly symptoms start appearing. COVID-19’s symptoms will appear gradually, most of the time over the course of days, not in hours like the flu.
Strep or Flu or COVID: How Can You Tell?
Now that we are familiar with the similarities and differences between the flu and COVID-19, what about strep, the flu, and COVID-19?
Strep throat is another illness to be wary of as we head into the colder months. While the flu and COVID-19 are respiratory illnesses, strep throat is a bacterial infection. It is specifically caused by group A Streptococcus bacteria. Strep throat, while still similar to the flu and COVID-19, might be easier to tell apart.
The common cold is another frequent illness with overlapping symptoms, but it is caused by different viruses and is generally milder.
Each of these illnesses—strep, flu, and COVID-19—can lead to different complications, so accurate diagnosis and treatment are important.
Similarities: Strep vs. COVID vs. Flu
While they are all very different from one another, there are still symptoms they all share in common. With the flu, strep throat, and COVID, a sore throat is not the only shared symptom. Shared symptoms include:
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- Sore throat
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- Fever
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- Headache
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- Body aches
Just like the flu, strep symptoms can appear suddenly and very quickly. Thankfully there are more differences between strep, flu, and COVID-19.
Rapid Testing LLC offers curbside strep testing at Advanced Urgent Care’s clinics – all without a provider visit.
Differences: Strep vs. Flu vs. COVID
Strep throat usually causes additional symptoms that are typically not attributed to the flu or COVID-19 including:
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- Pain when swallowing
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- Small red spots on the roof of mouth
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- Swollen, red tonsils
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- Swollen lymph node on neck
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- A rash
Strep symptoms appear quickly and suddenly unlike COVID. Another difference is that strep usually does not cause cough, congestion, or shortness of breath.
Sore Throat Causes and Diagnosis
A sore throat is a common symptom that can be triggered by a variety of infectious diseases, most often caused by either viral or bacterial infections. One of the most well-known bacterial causes is strep throat, which results from infection with Streptococcus bacteria. Strep throat typically presents with a sudden, severe sore throat, pain when swallowing, fever, and swollen lymph nodes. Unlike viral infections, strep throat rarely causes cough or nasal congestion, making these key differences important for an accurate diagnosis.
Viral infections, such as the flu (caused by influenza viruses) and COVID-19 (caused by SARS-CoV-2), can also lead to sore throat, but they often come with additional symptoms like runny or stuffy nose, cough, body aches, chills, and sometimes a loss of taste or smell. These contagious respiratory illnesses can range from mild to severe, and symptoms like difficulty breathing, severe fatigue, or muscle aches may signal a more serious illness that requires prompt medical care.
Because sore throat congestion and other symptoms can overlap between strep throat, the flu, and COVID-19, accurate diagnosis is essential. Rapid tests and throat cultures are used to detect Streptococcus bacteria for strep throat, while PCR or rapid antigen tests can confirm COVID-19. For the flu, rapid flu tests are available to help determine the cause of your symptoms. Identifying the correct cause ensures you receive the most effective treatment options—antibiotics for strep throat, antiviral medications for the flu or COVID-19, and supportive care or home remedies for milder viral infections.
It’s important to seek medical attention if your sore throat is accompanied by severe symptoms such as difficulty breathing, persistent high fever, severe fatigue, or muscle aches, or if your symptoms last longer than two weeks. Early diagnosis and treatment can help prevent complications like rheumatic fever from untreated strep throat or more serious illnesses from viral infections.
Prevention plays a key role in reducing the spread of these infectious diseases. Practicing good hygiene, such as frequent handwashing and avoiding close contact with those who are sick, can lower your risk of infection. Getting a flu shot each year and staying up to date with COVID-19 vaccines are also effective ways to protect yourself and those around you from severe illness.
By understanding the key differences between strep throat, the flu, and COVID-19, and recognizing when to seek medical care, you can help prevent complications and ensure a quicker recovery. If you’re experiencing a sore throat with other concerning symptoms, don’t hesitate to consult a healthcare provider for accurate diagnosis and appropriate treatment.
Curbside Rapid Testing Available!
Advanced Urgent Care & Occupational Medicine in Colorado and Rapid Testing LLC are partnering to provide curbside rapid COVID, flu, and strep testing at all of our clinics. A rapid test is a quick diagnostic tool used to confirm strep, flu, or COVID-19, enabling timely treatment. Testing is available without a visit with a provider and you’ll receive results the same day as testing. Click here to learn about the curbside tests and to schedule today!
Over-the-counter pain relievers can help manage symptoms such as fever and body aches while awaiting test results or during recovery.
Keep in mind, if you or your child test positive for strep, you will need to see a provider in order to treat the infection. If left untreated, there is a high risk for rheumatic fever or scarlet fever. It is also advised to seek treatment for a positive COVID test if feeling unwell.
Still Not Sure? Visit Us!
If you feel sick, it may be stressful to determine what you have. If you are experiencing any of the symptoms above, we recommend seeking medical care with an in-clinic or telehealth visit at Advanced Urgent Care & Occupational Medicine in Colorado. If the medical provider orders tests, we will schedule you for curbside testing at our clinic location nearest to you. We have urgent care clinics in Aurora, Broomfield, Brighton, Thornton, and Westminster.