Key takeaways:
Shortness of breath is a common symptom of coronavirus when paired with fever and cough.
Breathlessness is even more common amongst hospitalized patients.
In symptomatic people, shortness of breath does not usually present itself until between day 5 and 8.
Lots of different medical conditions can cause sudden shortness of breath: asthma, a chest infection, heart disease, anxiety, panic attacks, and yes — COVID-19.
COVID-19 is a respiratory disease caused by the SARS-CoV-2 virus. The virus affects cells in the airways, from the nose and throat down to the deepest parts of the lungs. When it’s in the nose and throat, it usually causes symptoms of a cold and cough. When the coronavirus lodges itself deep in the lungs, it can cause a lung infection, or pneumonia.
Shortness of breath is the feeling that you are out of breath, like you can’t catch your breath or that it’s hard work to inhale fully. Sometimes, it can feel like tightness around the chest. Another medical term for these symptoms is “dyspnea.”
Feeling short of breath can be normal. It can happen, for example, if you’re exercising, you’re at a high altitude, or you’re anxious. But if the shortness of breath doesn’t go away when you rest, or you feel short of breath after little or no activity, that’s a sign that something is not right.
Shortness of breath can come on suddenly in otherwise healthy people. It can also be a part of daily life for many people with a chronic lung or heart condition.
Shortness of breath is usually not an early symptom of COVID-19. Data suggests that feeling breathless usually comes on over the course of a week after other symptoms start. So imagine having a coronavirus infection with no symptoms for 5 days before developing mild symptoms of fever, tiredness, loss of taste and/or smell, and body aches. It may be 10 days before you start to feel breathless — and it could be even longer.
Some statistics: According to clinical studies, shortness of breath develops on average between day 5 and day 8 of symptoms. Note that these are average (median) numbers. Life-threatening shortness of breath can happen at any point during the course of COVID-19 and should always be taken as a sign that you need to seek urgent medical attention.
One of the symptoms of COVID-19 is shortness of breath. In fact, the combination of shortness of breath with fever and a dry cough is seen as being highly suggestive of a COVID-19 infection.
How common is shortness of breath in all people with COVID-19? Well, one study from early in the pandemic found that 39% of inpatients and outpatients reported experiencing shortness of breath on the day of testing for COVID.
Shortness of breath is still less common than fever and cough, but overall is the most prevalent symptom in people hospitalized due to COVID-19.
People with a mild form of COVID-19 are less likely to have shortness of breath than those with more severe disease. Why? Shortness of breath is caused by an infection in the lungs known as pneumonia. Not everyone with COVID-19 gets pneumonia, though. If you don’t have pneumonia, you probably won’t feel short of breath.
Some statistics: Based on results from clinical studies, it’s estimated that between 1.4% and 7.6% of people who had a mild coronavirus infection felt shortness of breath.
Feeling breathless with COVID-19 usually means the lungs are infected. If the coronavirus has caused pneumonia, then — depending on how serious it is — the lungs may struggle to get enough oxygen into the bloodstream. This is a problem because oxygen is an essential nutrient for every organ in the body. Not having enough oxygen in the blood makes us feel out of breath. It also makes the body breathe harder and faster to try to get more oxygen, which also makes us feel breathless.
Having shortness of breath can predict a more severe illness. Those who are unlucky enough to get pneumonia from COVID-19 are more likely to feel breathless than those who do not get it. They are also more likely to experience severe illness, often needing hospitalization and oxygen to help them breathe. Sometimes, they even need to be placed into an artificial coma and have a machine breathe for them in an effort to try and buy time until the lungs heal. This is called mechanical ventilation and can only be done in an intensive care unit or a similar environment.
Some statistics: In a review of 30 studies looking at patients with COVID-19, about 45% of those with severe infections were breathless when they were hospitalized.
Here are the most common symptoms of COVID-19:
Fever or chills
Dry cough
Shortness of breath
New loss of smell (and sometimes taste)
Fatigue
Muscle or body aches
Headache
Sore throat
Congestion or runny nose
Nausea or vomiting
Diarrhea
Of these, anosmia — loss of smell — is one of the strongest signs that you might have COVID-19.
Fever as a symptom of COVID-19 needs a little more explanation.
First, whether you have a fever or not depends on how you define “fever.” For example, is a fever a temperature above 99.5°F? Or is it above 100.4°F?
Second, while 99% of people hospitalized with COVID-19 had a “fever,” 20% of them only had a very low-grade fever (below 100.4°F).
“Lower fevers” seem to be more common in mild cases.
Not everyone with COVID-19 gets a fever, and if a fever happens, it doesn’t necessarily go on the whole time they’re ill. In about half of patients with COVID-19, fever developed as the illness progressed.
And remember, new, unexplained shortness of breath can be a sign of other things, not just COVID-19. So if you have new shortness of breath for no obvious reason, whether you have a fever or not, it’s best to call for medical advice ASAP.
When should you worry about shortness of breath? It depends on whether you usually get breathless or not. For example, do you have an underlying condition such as asthma, COPD, heart failure, or anxiety? Is what you’re feeling similar to what you’ve felt before, or is it different?
If you don’t usually get breathless, could this be anxiety or a panic attack? It could be if your heart is racing, your palms are sweaty, and your shortness of breath settles when you are relaxed or distracted.
Knowing what is normal for you is a good place to start when trying to figure out if things are worse than normal. Being infected with coronavirus can make breathing more difficult if you already have asthma or COPD, but so can stress and other respiratory viruses.
If you have shortness of breath that is new or worse, and you feel breathless with small amounts of activity, then you need to seek medical attention. This was true before COVID-19, and it’s still true now.
If you have any of the following, you should seek immediate emergency medical attention:
Tightness or pain around your chest that doesn’t go away
Sudden confusion or extreme sleepiness
Bluish lips or face
If you have a fever, a dry cough, and tiredness (with or without shortness of breath), you are likely to have COVID-19 until proven otherwise, and you should self-isolate.
If shortness of breath is your only symptom, and you have neither a cough nor a fever, it’s less likely to be COVID-19.
The best option is to take an at-home test or visit your doctor or pharmacy for testing.
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