Coronavirus Symptoms and Complications

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Editor's note: Updated May 5, 2020.

When coronaviruses infect people, they cause respiratory illnesses. Some strains cause the common cold, while other strains can cause very severe respiratory disease or syndrome (SARS). COVID-19, which stands for Coronavirus Disease 2019, involves a strain that is new in humans. It is a betacoronavirus like MERS (2012 outbreak) and SARS (2003 outbreak). Scientists have named the newly discovered virus SARS-CoV-2. On March 11, 2020, the World Heath Organization announced that COVID-19 is a pandemic due to its rapid spread across the globe and its severity.

The COVID-19 Symptom Comparison Chart highlights some differences between COVID-19, flu and the common cold. To help protect yourself and your family, know the signs and symptoms of COVID-19, how the infection progresses, and who is most at risk of developing coronavirus complications.

Coronavirus Symptoms

Coronavirus symptoms are very similar to influenza (flu). They include:

  • Cough, which may produce phlegm (sputum)
  • Fatigue
  • Fever
  • Shortness of breath

Symptoms may appear within 2 to 14 days of becoming infected; the median is 5 days. COVID-19 symptoms are usually mild—fever, dry cough, some body aches, maybe shortness of breath—and begin gradually. In fact, experts believe about 25% of people with the infection never develop symptoms or feel sick, but they are still contagious. This makes it very different from MERS and SARS, which are usually severe and often deadly. It also makes it different from the flu, which usually starts very suddenly.

Unexpected symptoms of COVID-19 include loss of sense of smell (anosmia), even in the absence of any other symptoms.

Mild COVID-19 symptoms last a few days to a week, but it can take a couple of weeks for symptoms to subside in some cases. Some people experience more uncomfortable symptoms, including fever above 100.4 (degrees Fahrenheit), chills, cough, body aches, and fatigue. Anyone with shortness of breath or chest pain should be evaluated by a medical professional.

Unlike the flu, COVID-19 usually causes mild disease in children. In fact, the disease tends to be more like the common cold in children, so far. At this time, young children do not seem to be a high-risk group unless they have an underlying condition, such as asthma. However, there have been cases of serious disease and some children have died of COVID-19.

What to Do If You Have Flu-like Symptoms

Anyone with symptoms of cough, fever, and shortness of breath should seek prompt medical care.* Call ahead to your doctor or urgent care clinic first. They will ask you questions and give you special instructions to follow. In the United States, it is much more likely your symptoms are from the flu virus than COVID-19. (A rapid flu diagnosis within the first 48 hours allows for treatment with antivirals that can shorten the illness.) If you or your child has mild cold symptoms, do not call your doctor. Stay home until you feel better to avoid spreading the cold to others. Call your pediatrician or an urgent care clinic if your infant has a fever or difficulty breathing.

*If you know you could have been exposed to COVID-19, call your doctor, urgent care clinic, or state health department. Do not go directly to a doctor's office, urgent care, or hospital. Even though primary care doctors do not test for the coronavirus, they determine if you are a good candidate for testing.

For most people, coronavirus treatment is much the same as treating the flu. It focuses on resting and treating the symptoms of fever, cough, and shortness of breath. Unlike the influenza virus, there is no antiviral medicine currently available to shorten the duration of symptoms. Antibiotics aren’t effective for either the flu or COVID-19, as they are viruses and antibiotics only treat bacterial infections. Scientists and drug makers around the world are studying potential COVID-19 treatments in clinical trials.  

Potential Coronavirus Complications

Some people develop a severe case of COVID-19. Older people and anyone with chronic medical conditions, such as heart problems or diabetes, have the highest risk of severe disease. They may develop difficulty breathing, pain with breathing, and other serious respiratory symptoms. It can take several weeks or longer to recover.

According to WHO, about 80% of people recover from COVID-19 without special treatment. So, most people have a very favorable coronavirus prognosis. About 15 to 20% of cases have become quite severe. Those who develop a serious illness with COVID-19 require hospitalization to prevent and treat complications. Possible complications include:

  • Severe acute respiratory syndrome (SARS)

There is also a risk of death when the illness is severe, often from a secondary bacterial infection and other causes. So far, coronavirus has been fatal in about 7% of people with COVID-19 illness worldwide, based the number of confirmed cases and deaths.

Contact your health department for the most up-to-date information about COVID-19 cases in your state and county. For general COVID-19 information, visit the CDC or WHO websites.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Feb 28
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